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close this bookBasic Concepts in Environment, Agriculture and Natural Resources Management: An Information Kit (IIRR, 1993, 151 p.)
Open this folder and view contentsIntroduction
Open this folder and view contentsEcological basics
Open this folder and view contentsFreshwater and marine ecosystems
Open this folder and view contentsForest ecosystems
Open this folder and view contentsGlobal warming and acid rain
Open this folder and view contentsPollution
Open this folder and view contentsOthers

Use of workshop

Many environmental issues involve complex and technical information and processes which are difficult to understand. Majority of the people do not yet understand the very basic issues related to, for example, ozone depletion or global warming or the loss of biodiversity.

The difficult process of simplifying such kinds of information for specific audiences is not systematically implemented on a large scale in the Philippines.

The International Institute of Rural Reconstruction (IIRR) believes that there is currently a great need for quality educational printed materials which can be used by teachers, trainors, educators, policymakers, key sector leaders and others throughout the Philippines in the area of environmental education. These printed materials will convey the difficult-to-understand concepts into more appropriate information kits for wider dissemination.

IIRR is aware that there are government and nongovernment organizations (GOs/NGOs) that are currently producing environmental education materials. Therefore, the primary step the Institute took was to network with these GOs and NGOs to establish the state-of-the-art for environmental education materials within the Philippines.

The information kit on the Basic Concepts in the Environment, Agriculture and Natural Resources Management was produced through the use of a workshop involving technical and communication experts. The workshop approach has been successfully implemented by IIRR to speed up and improve the production of various technology-focused kits, such as the Bio-Intensive Gardening, Regenerative Agriculture Technologies, Agroforestry, Low-lnput Rice Production and Integrated Agriculture-Aquaculture Technologies.

The workshop was held on September 14-19, 1992, at the IIRR Campus in Silang, Cavite, Philippines. The participants came from key organizations involved in environmental work, such as Center for Environmental Concerns (CEC), Department of Education, Culture and Sports (DECS), Department of Education, Culture and Sports-EDPITAF (DECS-EDPITAF), Department of Environment and Natural Resources (DENR), Department of Environment and Natural Resources-Protected Areas and Wildlife Bureau (DENR-PAWB), Department of Health (DOH), Ecosystems Research and Development Bureau (ERDB), Forum for Rural Concerns (FRC), Green Forum, Haribon Foundation, Institute for Environmental Sciences and Management (IESAM), International Institute of Rural Reconstruction (IIRR), Marine Science Institute (MSI), Philippine Environmental Action Network (PEAN), Philippine Ecological Network (PEN), Philippine Rural Reconstruction Movement (PRRM), Philippine Wetland and Wildlife Conservation Foundation, Inc. (PWWCFI) and University of the Philippines at Los Ba(UPLB). Because these participants consisted primarily of the practitioner-types, reflective of the intended user-audience, the potential relevance of the kit was improved. In addition, the papers underwent instant critical peer review and revision, a process which normally takes several days or even weeks. Finally, the presence of communication specialists (writers, editors, artists) facilitated the appropriate presentation and design of materials.

This technology information kit focuses on Philippine situation, is designed for learning about basic concepts, issues and problems related to environment and natural resource use and degradation and is intended for nationwide use by students, trainors and GO/NGO policymakers.

Workshop participants

1. Mr. Rafael Almonte
Center for Environmental Concerns (CEC)
III-A Scout Lozano St.
Barangay Laging Handa, Quezon City

2. Ms. Maribeth Reyes-Baril
Haribon Foundation
340 Villamor Street
San Juan, Metro Manila 1500

3. Mr. Rusty BiBR>Sciences
UPLB, College, Laguna
Reconstruction (IIRR)
#48 Gatuslao Street, Bacolod City

4. Mr. Emmanuel Carmona
Broad Initiatives for Negros Development
Green Alert Negros Environmental Network
2nd Floor, Door 1, Silos Building
Rosario St., Bacolod City~6100

5. Dr. Virginia Cuevas
Institute of Environmental Sciences and
Management (IESAM)
UPLB, College, Laguna

6. Ms. Dolores Ariadne Diamante
Appropriate Technology Unit, IIRR
Silang, Cavite

7. Ms. Teresita Felipe
Department of Education, Culture and Sports
University of Life Complex

8. Ms. Estrella Fernandez
Philippine Rural Reconstruction Movement
Kayumanggi Press Building
940 Quezon Avenue, Quezon City

9. Dr. Sandy Fortuna
Field Operational Research Division, IIRR
Silang, Cavite

10. Dr. Julian F. Gonsalves
Vice-President for Program, IIRR
Silang, Cavite

11. Mr. Juan Carlos Gonzalez
Wildlife Biology Laboratory
Institute of Biological
International Institute of Rural

12. Mr. Fernando Hilario
Forum for Rural Concerns (FRC)
Room 336, Eagle Court Condominium
26 Matalino St.
Central District, Quezon City

13. Mr. Eusebio Imperial
Appropriate Technology Unit, IIRR
Silang, Cavite

14. Mr. Greg Ira
Appropriate Technology Unit, IIRR
Silang, Cavite

15. Dr. Marie Antonette Juinio
Marine Science Institute.
University of the Philippines
Diliman, Quezon City

16. Mr. Scott Killough
Appropriate Technology Unit, IIRR
Silang, Cavite
Meralco Avenue, Pasig, Metro Manila
17. Mr. Ben Maata
c/o IIRR
Silang, Cavite

18. Mr. Eulogio Masilungan
Appropriate Technology Unit, IIRR
Silang, Cavite

19. Ms. Manolita Morales
Philippine Wetland and Wildlife
Conservation Foundation, Inc.
Unit 2, -A. Sing Building
295 Duterte St.
Banawa, Cebu City 6000

20. Ms. Malou Moreno
Ecosystems Research and Development
Bureau (ERDB)
UPLB, College, Laguna

21. Dr. Ismael Pastor
Department of Health
San Lazaro Compound
Tayuman, Sta. Cruz, Manila

22. Ms. Thelma Perez
Protected Areas and Wildlife Bureau
Department of Environment and Natural
Quezon Avenue, Diliman
Quezon City

23. Mr. Eseng Quintos
Field Operational Research Division, IIRR

24. Ms. Nelia Quiz
UPLB, College, Laguna

25. Mr. Nestor Roderno
Appropriate Technology Unit, IIRR
Silang, Cavite

26. Ms. Dolores Rubio
Health and Nutrition Center
Department of Education, Culture and Sports
University of Life Complex
Meralco Avenue, Pasig
Metro Manila

27. Mr. Romeo San Buenaventura
Appropriate Technology Unit, IIRR
Silang, Cavite

28. Mr. Teodoro Sevilla
Appropriate Technology Unit, IIRR
Silang, Cavite

29. Mr. Leland Taoingan
Quezon Avenue, Diliman
Quezon City
Silang, Cavite
30. Ms. Meng Yaun
Field Operational Research Division, IIRR
Silang, Cavite

Support staff


Dr. Julian Gonsalves, Mr. Greg Ira, Mr. Scott Killough and


Mr. Jaime Ronquillo


Ms. Donnie Diamante, Ms. Lyn Capistrano-Doren, Mr. Greg Ira,

Mr. Scott Killough, Mr. Eseng Quintos, Mr. Jaime Ronquillo and

Mr. Roger Villar


Mr. Albert Ba Mr. Boy Belardo, Mr. Rafael Bordeo, Mr.

Ric Cantada, Mr. Mitchell Doren, Mr. Bernie Remoquillo and Mr.

Roger Villar


Ms. Lhai Kasala, Ms. Angie Poblete, Ms. Jel Montoya, Mr. Rolly

Secretarial Staff:

Ramos, Ms. Ely Paredes, Ms. Violy Alvez, Ms. Gemma Boado,

Ms. Tess Aquino, Ms. Girlie Belen, Ms. Hilda Amon and Mr. Gerry


Glossary of commonly used environmental terms


a mixture of invisible, odorless and tasteless gases that surround the earth


simple, free-floating water plants

Ambient air

any unconfined portion of the atmosphere; the outside air


growing or living upon water


sand, gravel or rock formation found below the earth's surface which is saturated with water


the mass of air surrounding the earth held by the force of gravity


microscopic, single-celled plants


a material that decomposes in the environment as a result of biological action by microorganisms


the amount of living matter (plants and animals) in a given habitat


leaf area of a woodland


animals that eat meat (other animals)

Carrying capacity

the maximum number of animals that an area can support


green photosynthetic coloring matter in plants


the chemical process of burning which releases heat, light and chemical by-products


lowering of the quality of a resource


using up the total quantity of a resource


a person who studies the relations between organisms and their environment


a unit of the environment comprising the interactions of all organisms and the physical components within a given area


pollutant discharged into the air

Endangered species

plants or animals in danger of becoming extinct through all or part of its range; plants or animals whose numbers have been reduced to a critical level or whose habitats have been so drastically reduced that they are deemed to be in immediate danger of extinction


plants or animals which are unique to particular locality or place and cannot be found elsewhere, e.g., Philippine Eagle or Mindoro Crocodile


the capacity to produce motion, heat or light

Energy conservation

planned management of energy resources which conserves, protects and prevents waste

Energy resources

a measure of national wealth by the production of usable power, such as heat and electricity

Environmental impact

changes in the environment caused by some form of management or mismanagement


the wearing away of land surface


plants or animals which are not native to an area


plants and animals which have not been sighted in the wild during the past 50 years




an organic or inorganic material that is added to the soil to supply elements essential to plant growth



Food chain

an arrangement of predator-prey relationship in an ecosystem

Food web

the interconnected food chains within an ecosystem


all browse and non-woody food that is available to livestock or game animals


a complex community of associated trees, shrubs, other plants and animals


the art and science of managing forests so as to yield, on a continuous basis, a maximum in quality and quantity of forest lands to satisfy human needs

Fossil fuels

hydrocarbon compounds derived from the remains of organisms (plants and animals) buried millions of years ago


involving the entire world

Ground water

water found below the earth's surface

Ground-water recharge

water which seeps through the earth's surface and into the ground water aquifers


the area where an animal or plant naturally lives and grows

Hazardous or toxic waste

waste that poses a serious threat to human health even at extremely low concentrations

Hazardous-waste site

allocation where hazardous waste poses a potential threat to the environment

Heavy metals

metallic elements with high molecular weights; generally toxic to plant and animal life


animals that eat plants

Hydrologic cycle

continuous circulation of water between the oceans, atmosphere and the earth's surface

Industrial waste

waste generated by industries

Irrigated lands

agricultural lands whose water requirements are met by man-made or artificial structures rather than by natural means, such as rain; irrigated lands have water the whole year as against rainfed lands which have water only during the rainy season

Limiting factors

factors that restrict the population potential of a species

Lowland areas

rainfed or irrigated farming land that is flat or gently undulating and that is not very high above sea level


to move from one region or climate to another for feeding or breeding

Migratory birds

birds which travel from one place to another depending on the season


a naturally-occurring inorganic substance in the soil


a layer of plant residue on the soil surface

Municipal waste

waste from cities, primarily sewage


active at night

Nonpoint source pollution

pollution which enters the environment from a wide-area

Nonrenewable energy

resources which cannot be replaced once they are used


mineral elements and compounds (including water and air) which a plant uses for tissue growth and maintenance


animals that eat both animals and plants

Organic compounds

compounds composed of chemicals containing carbon; examples: pesticides, solvents, cleaning compounds, paints

Organic material

plant and animal matter in various stages of decay

Ozone (O3) layer

layer of the atmosphere that protects the earth from the harmful ultraviolet radiation in sunlight


a scale which represents alkalinity or acidity


the downward movement of water into the soil


the ability of the soil to allow air and water to move through it


a chemical used to kill or control pests


a natural, thick, yellow-to-black, flammable liquid hydrocarbon mixture found principally beneath the earth's surface


the process of producing carbohydrates from water, carbon dioxide, chlorophyll and sunlight


suspended, floating, microscopic plants and animals in the water

Plant nutrients

elements essential for plant growth

Points source pollution

pollution which can be traced to a point of discharge


any introduced gas, liquid or solid that makes a resource unfit for a specific purpose


the presence of matter or energy whose nature, location or quantity produces undesirable environmental effects; a reduction in the quality of the environment by the introduction of impurities

Population density

the number of people or animals per unit area; example: people per square kilometer


animals that hunt, kill and consume other animals


an animal taken as food by a predator

Rare species

plants and animals with very small populations that are not, at present, endangered but are at risk.

Rainfed farming land

agricultural land which depends solely on rainfall for its water requirements transforming barren mine areas as nearly as possible to their original condition


to reuse or process waste for beneficial purposes


transforming waste products into new products

Refuge, reserve or wilderness area

an area of land set aside for the protection of wildlife

Renewable energy

energy resources that can be replaced by natural regeneration or human efforts after they are used


wildlife found in a certain locality but may also be found elsewhere


the angle of the soil surface expressed as a percent of rise and fall


the outer portion of the earth's crust that supports plant life


the process by which fish deposit eggs


a group of organisms that resemble each other closely and that interbreed freely


the progressive development of vegetation which replaces one plant community with another in order to reach a climax condition

Surface water

water visible on the earth's surface


the physical features (natural and man-made) on the land's surface


the release of water vapor by leaves into the air

Upland areas

hilly to mountainous lands, including plateaus and table lands lying at high elevations


growth or expansion of cities


useless, unwanted or discarded material

Water pollution

water which is made chemically, biologically or physically impure or unfit for use


the total drainage area where water flows to a common point


the actions that break down rock into soil


swamps or marshes, especially as areas used by wildlife


plants and animals found in their natural habitat undisturbed by man or free from human interference; mammals, birds and fishes which are not domesticated or are free-ranging in their naturally associated habitats


a living barrier of trees and shrubs designed for protection from wind


Darold Hehn and Bob Newport. Introduction to Natural Resources. 1991. Developed by the Mid-America

Curriculum Consortium. Stillwater, OK.

List of references

An Introduction to Tropical Rainforests. Whitmore, T. C. Clarendon Press, Oxford University Press 1990.

A Primer on Wildlife Conservation Education. Baril, J. A. and M. A. Reyes. Haribon Foundation 1991.

Ating Agham (Third Year). Vol XI, No.2, SY 1991-1992. Metallic Pollutants in Natural Waters (condensed), pp.67.

Bato Balani (Freshman), Vol. II No. 5, SY 1991-1992. Effects of Air Pollutants on the Environment. Barril, Carlito, pp. 9-11.

Biology, Epidemiology and Management of Pyrodinium Red Tides. Maclean, J. L., Hallegract G. ICLARM. Manila. 1989

Birds of the Philippines. Pedro C. Gonzales and Colin P. Rees. Haribon Foundation for the Conservation of Natural Resources, Inc. 1988.

Brown and Fisher.1918

Conserve Our Marine Turtles Poster. Pawikan Conservation Project, DENR 1990.

Conserving the World's Biological Diversity. McNeely, Jeffrey A., et. al. IUCN, WRI, WWF-US, World Bank. 1990.

Coral Reef Ecosystem. Analysis of Marine Ecosystem. Lewis, J.B. Edited by A.R. Longhurst. Academic Press, Ltd., San Diego California. 1981.

· DENR-Calendar. 1991.
· DENR Forestry Master Plan. 1990
· DENR Philippine Environment in the '80s
· DOH Summary of Health Effects of Typhoon Ruping. 1990.

Earthquake and Tsunamis. PHILVOCS. DOST. Manila. 1991.

Encyclopedia of Occupational Health and Safety. 1985. 3rd Revised Edition. ILO Publication, 2 Volumes. 2538 pages.

Fundamentals of Ecology. Third Edition. Odum, Eugene P. W. B. Saunders Co. Philadelphia. 1971.

Global Status of Mangrove Ecosystem. Saenger, P. E., J. Hegert and J. D. S. Davie. Commission Paper No.3. International Union for Conservation of Nature and Natural Resources, AU. du. Mont. Blanc. 1196 Ciland, Switzerland. 1983. p. 88.

Greenpeace Pacific Campaign. Spring 1991.

· Health Alert. Issue No. 113. January 1991
· Health Alert. Issue No. 118. June 1991.
· Health Alert. Issue No. 124. December 1991.

Health Effects of Volcanoes: An Approach for Evaluating the Health Effects of an Environmental

Hazard. Buist, A. S., R. S. Bernstein. Annual Journal Publication on Health; 1986; 76(8). 84 pp.

Information Handbook for Health and Nutrition. Personnel. HNC. DECS. S. 1991.

Investing in Biological Diversity: US Research and Conservation Efforts in Developing Countries. Abramovitz, Janet N. World Resources Institute March 1991.

List of Rare, Endangered, Threatened, Vulnerable, Indeterminate, Insufficiently Known Philippine Species. Protected Areas and Wildlife Bureau, DENR.

Living the Environment: An Introduction to Environmental Science. Miller, Jr. G. Tyler. Fifth Edition. Wadsworth Publishing Co., Belmont, California. 1987.

Man, Agriculture and Tropical Rainforest. Sajise P. et. al. DENR, 1990. 25 Years -- Philippine Forestry Action Plan.

Managing our Natural Resources. William G. Camp and Thomas B. Daughtery. Delmar Publishers, Inc. Albany. N. Y. 1988.

Mangroves of Asia and the Pacific: Status and Management. Technical Report of the UNDP/UNESCO Research and Training Pilot Programme on Mangroves Ecosystems in Asia and the Pacific. 1987.

Morbidity and Mortality Weekly Report. Contour for Disease Control. Earthquake Disaster-Luzon Philippines. August 1990; 39 (34) 573-576.

Mt. Pinatubo Wakes After 600 Years of Slumber. Philippine Institute of Volcanology and Seismology. DOST. Manila. 1991.

Outreach, Issue No.56.

1991 Philippine Statistical Yearbook. National Statistical Coordination Board.

Philippine Wildlife. Tan, Jose Ma. Lorenzo P. Bookmark. 1992.

Pollution, A Wall Chart on World Resource: Their Use and Abuse. WWF-IUC. 1984.

Polluted Metro Manila. Primer Series No. 12. Lingkod Tao-Kalikasan (In Service of the Human-Earth Community). Secretariat for an Ecologically-sound Philippines.

Proceedings of the International Conference on Alternatives in Animal Husbandry. Engenhard Boechache and Viola Mollentihin. University of Kassel in Witzenhausen (Germany).

Production and Harvesting. Los BaLaguna. PCARRD, 1991,96 p. (Philippines Recommends, Ser. No. 74 1991).

Red Tide Update: Nos 1 - 17, 1992. Environmental Health Service. Department of Health. Manila. 1992.

Report on the Philippine Environment in the Eighties. Environmental Management Bureau. DENR. Quezon City. November 1990.

Resource Book on Sustainable Agriculture for the Uplands. Mindanao Baptist Rural Life Center/Mag-ungmad Foundation, Inc./World Neighbors/International Institute of Rural Reconstruction. 1990.

Review of the Protected Areas System in the Indo-Malayan Realm. John and Kathy McKinnon, IUCN. CNPPA. UNEP 1986.

Rural Community Property Resources: Contributions and Crisis. N. S. Jodha. International Center for Integrated Mountain Development, ICIMOD. Nepal. 1990.

Small-scale Livestock Production Project. A Guide for Planning by Linda Jacobs.

Sourcebook in Environmental Education for Secondary School Teachers. Population Dynamics in an Ecosystem. Dr. R. C. Sharma and Merle C. Tan, eds. UNESCO, Bangkok. 1990.

State of the Art of Philippine Lakes. PCARRD. 1981. Los Ba Laguna.

Student Manual: Introduction to Natural Resources. 1992 - 1993. Section 4 - Biodiversity.

Teacher's Guide to World Resources. 1992-1993. Section 4-Biodiversity.

Teacher's Modules Integrating Health and Nutrition. TCP-IEC. HNC, NCP, UNICEF.

The Impact of Corporate Mining on Local Philippine Communities. Andrew, John P. ARC Publication. 1983.

The Impact of Mining on the Physical Environment.

The Killer Quakes. PHILVOCS. 16 July 1990. DOST. Manila. 1990.

The Philippine Environment in the Eighties. Department of Environment and Natural Resources.1990.

The Philippines Recommends for Mangrove. Philippine Council for Agriculture, Forestry and Natural Resources Research and Development.

The Public Health Consequences of Disasters, 1989. Gragg M. B. CDC Monographs. US DHHS: PHS. October 1989. 128 pp.

Toxic and Hazardous Wastes. Atlas of the Environment; Lean, Geoffrey; Don Hinrichson; Adam, Markhar. Bason Marketing, Limited. 1990. pp. 101-104.

Usborne Science and Experiments Ecology. Spurgeon, Richard. Edited by Stephen Wright.

UP-ISMDED Framework for Environmental Education.

UPDATE. Haribon. November - December 1990.

Wasteland News. Common Property and Local Institutions. Pankaj Kumar, Viven Lubo, Jaya Chatterji and Awind Khase. November - January 1992.

Wildlife 101 Manual. Wildlife Biology Laboratory. IBS-CAS, UPLB.

Ecosystem degradation

Wheel of interacting forces affecting any ecosystem

The above is an illustration of the different factors involved in ecosystems degradation. The biggest responsibility involves the policy planners and implementors at the national, regional, provincial and municipal levels. The community (townsfolks, students, public officials, media and private entities) should play an important roles in the local use of the resources within each ecosystem. The role each one should play could be policing, reporting, organizing and taking hands-on-action to abate further loss of a tree, orchid, medicinal plants, bird and other animal species in an ecosystem. All of these are part of our national heritage. The conservation of which can be as joyful as the successful captive breeding of the Philippine Eagle or as sad as the plight of the Tamaraw. Much of the future of Philippine ecosystems depends on how we develop the social system which affects the ecological system.

If left alone and not irreversibly damaged, an ecosystem has the capacity to regenerate itself.

Impact of human activities on different ecosystems




1. Forest Ecosystem 6.7 million ha

Clear-cut logging

Continuous loss of forest cover


Rate of extraction at 100,000 ha/yr

Slash-and-burn activities

Loss of soil nutrient

Forest slopes soil exposed to onslaught of varying climatic conditions

Forest harvesting of wood/non wood products

Loss of soil fertility

Varied activities of forest dwellers

Loss of plant/animal resources

2. Grassland Ecosystem 10.6 million ha

Forest tires

Grassland areas further degrades

Kaingin practices

Soil erosion rate (an average

Harvesting of non-timber products

of 73 ha per year)

Mining activities

Increased surface run-off

Herbivore production

Loss of plant/animal resources

Human activities aggravating conditions of watershed areas

3. Freshwater Ecosystem 0.90 million ha


Loss of critical watersheds (19 out of 58)

Operations of mini-hydro power plants


Establishment of swimming resorts using natural springs

Increased silt-load

sedimentation of freshwater

Ecotourism activities

bodies and adjoining zones

Domestic agro-residential industrial sites of water

Affects water quality


Affects yield regulation service for diminishing water agro-industrial-domestic uses; power generation capability


Loss of ecotourism value

Open fisheries

Encroachement of exotic species

Drainage and conversion to agriculture

Loss of native plants/animals

Eutrophication of lakes

Biologically dead rivers; drainage channels

High level of organic and other polluants

4. Rural-urban Ecosystems11.8 million ha

Rural-urban community activities

Affecting life support system

Domestic; agro-industrial production



Lack of quality water


No water

Navigation traffic

Loss of lives, properties and industries

Decreased agricultural and industrial production

5. Mangrove Ecosystems

Mangrove harvesting

Affect mangrove productivity

Remnant 310,375 ha


Decreasing yield of fishery resources,

Land conversion for human settlement areas

Loss of habitat

Loss of nutrients

Conversion of mangrove areas into impoundments for fishy shrimp 210,456 ha

Loss of biodiversity

Conversion of 100,000 ha mangrove swamps into salt beds industrial and agricultural area for coconut and rice production


6. Coral Reef Ecosystems Remnant 2,245 kms

Open fisheries

Affect coral reef productivity

Dynamite fishing

Depletion of economically important fishing grounds

Coral reef harvesting


Muro-ami activities

Loss of biodiversity

Scuba diving


Habitat and niche

Habitat and niche

Habitat = address or home of an organism

· The area where an animal lives or its home, usually an ecosystem or an area within an ecosystem.

· Habitat relates mostly to the non-living physical or chemical conditions of the area such as temperature, rainfall, salinity, sunlight, soil and elevation.

· Habitat and the preservation of biodiversity

· Habitat conservation is directly related to species conservation. The protection of habitats is a more systematic and comprehensive way or preserving species. By protecting any given habitat, a host of species will automatically be protected. This is often more useful than trying to preserve a single species. The loss of habitat is the main cause of species loss in the world. For example, the preservation of mangrove habitat protects those plants and animals that are associated with it.

Niche = occupation of an organism in its community

· A species niche is composed of its habitat, plus the biological or living things found the habitat. The living component (plants and animals) of a habitat is called a community.

· Biological factors include location on the food chain (producers, herbivores, carnivores, etc.) predator/prey relationships and reproductive requirements.

· Interrelationships and interactions are important aspects of niche. For example, tall trees provide shade for plants and animals living under it; birds help disperse seeds of certain trees; and, worms help to aerate the soil.

· Temporal activities are also important in understanding niche. Activities which relate to temporal cycles such as day and night, lunar or seasonal cycles help to define the niche of an organism.

Specialized is generalized niches

Specialized niches apply to species which have very well-defined or narrow physical, biological or chemical requirements for survival. If an organism can only be found within very limited or specific conditions, it is considered to have a very specialized niche. The dugong is an example of an animal with a specialized niche. It requires seagrass beds for food and warm, calm waters for rearing its young. Animals such as the dugong with a specialized niche are more susceptible to extinction than animals with a generalized niche.

Generalized niches apply to species which can exist in a broad range of conditions. Humans are the best examples of species with a generalized niche. In the Philippines, as elsewhere, humans live in diverse conditions with an almost infinite variety of interrelationships. Other animals that are considered to have generalized niches are cockroaches, flies and rats.

Competitive exclusion principle

The fact that no two species can occupy the same niche is called the competitive exclusion principle. For example, two different species of Kingfisher may share the same habitat but may feed on different organisms at different times of the day or in different places.

Niche and ecosystems changes

Understanding the niche of species within an ecosystem will provide insights as to what the consequences of change may be. Two of the more common changes are the elimination of a species and the introduction of exotic or foreign species. The removal of a species whether through extinction or habitat loss can have many undesirable effects. This is often seen when pesticides eliminate beneficial as well as harmful insects. The result can be the removal of an important predator of harmful insects and subsequent increases in the pest population. Understanding the niche of the various organisms in a given habitat will help to predict potential effects of change. The introduction of exotic or non-native species can also bring about detrimental effects. If the introduced species is known to be very resilient and competitive and has a generalized niche, it may colonize-large areas to the detriment of native species. The Eurasian Tree Sparrow is an example of this in the Philippines.

The food chain

The food chain


· All lives exist in an ecological system. Organisms are interrelated by many things. One important relationship among plants and animals is the concept of food chain. Transfer of food energy in which one type of organism consumes another is referred to as the food chain.

· Plants receive energy from the sun and convert it into chemical energy through the process of photosynthesis. Similarly, plants get food from the soil. In both cases of energy transfer from the surf end the soil to the plans, some energy is lost as heat and cannot be used to make the living matter of the plant. Similarly, when plants are eaten by animals, some energy is lost in the transfer of energy from the plants to the animals. Typically, only about 10 percent of the energy is effectively transferred at each link of the food chain. This process can be represented by what is known as the food pyramid.

· All organisms that share the same general types of food in a chain are said to be at the same trophic level. Thus, green plants (producers) occupy the first trophic level, herbivores (primary consumers) occupy the second trophic level, carnivores (secondary consumers) which eat the herbivores occupy the third trophic level and top or secondary carnivores (tertiary consumers)—those that eat other carnivores - occupy the fourth trophic level. The classification of species into trophic levels is based on the function, rather than the species itself. Humans are considered to be omnivores, eating plants, therefore, functioning as a herbivore; and, eating animals, therefore, functioning as a carnivore.

· Food chains are not isolated sequences but are interconnected with one another. The complex series or network of many interconnected food chains is called a food web. Food webs are an important factor for understanding/he importance of maintaining plant and animal diversity in order to protect the interlocking nature of food chains and food webs. As plant and animal species are lost, breaks can occur in the food chain and food web.

· The most obvious form of species interaction in food chains and webs is predation. An individual organism of one species, known as the predator, captures and feeds on parts or all of an organism of another species, the prey. Humans act as predators whenever we eat any plant or animal food.

· An important principle affecting the ultimate population size of an omnivorous species, such as humans, emerges from a consideration of the loss of available energy at successively higher trophic levels in food chains and webs: The shorter the food chain, the less the loss of usable energy. This means that a larger population of humans can be supported if people shorten the food chain by eating grains directly (for example, 1 ha rice = 10 people) rather than eating animals that feed on the grains (grain - cattle - human).

Biological magnification

Biological magnification


· In an ecosystem, any change in the population of one organism is likely to have effects on other organisms in the same food chain or food web.

· This fact is illustrated by what is known as biological magnification. Biological magnification is the increase in concentration of certain fat-soluble chemicals in successively higher trophic levels of a food chain or food web. In other words, as chemical compounds move up through the various links of a food chain by being consumed by different organisms, the toxic effect of these compounds is magnified.

· Biological magnification plays a devastating role in certain types of pollution. Many air end water pollutants are either diluted to relatively harmless levels or are degraded to harmless forms by decomposition and other natural processes. This is true as long as the amount of these chemicals entering the environment is not excessive. However, some synthetic chemicals, such as the pesticide DDT, some radioactive materials and some toxic mercury and lead compounds, become more concentrated in the fatty tissues of organisms at successively higher trophic levels in various food chains and food webs.

· Biological magnification depends on two factors: chemicals that are soluble in fat, but insoluble in water; and, chemicals that either are not broken down or are broken down slowly in the environment.

· To illustrate the process of biological magnification, the example of the pesticide DDT moving through an estuarine ecosystem can be given. DDT is insoluble in water, soluble in fat and breaks down slowly in the environment. Thus, if each phytoplankton concentrates one unit of water-insoluble DDT from the water, a small fish-eating thousands of phytoplankton will store thousands of units of DDT in its fatty tissue. Then, a large fish that eats ten of the smaller fish will receive and store tens of thousands of units of DDT. A bird or human that feeds on several large fish can ingest hundreds of thousands of units of DDT. Of course, ingestion of high levels of DDT in plants and animals, including humans, can lead to chronic health problems and even death.

· Biological magnification of certain chemicals helps explain why dilution is not always the solution to some - forms of air and water pollution.

Nitrogen cycle

Nitrogen cycle


· Living things need nitrogen (N) to manufacture proteins. Plant growth can be limited by a lack of nitrogen available from the soil. Too little nitrogen can also cause malnutrition in humans because many of the body's essential functions require nitrogen-containing molecules, such as proteins.

· The nitrogen cycle outlines the process in which nitrogen is converted into various forms and transported through the biosphere.

· The nitrogen gas which accounts for 78 percent of the volume of the earth's atmosphere is not usable by most plants and animals. Fortunately, the process of nitrogen fixation allows for the conversion of atmospheric nitrogen gas into forms useful to plants. This process is accomplished by soil bacteria; rhizobium bacteria living in root nodules of leguminous plants such as beans, peas and ipil-ipil; blue-green algae such as azolla found in water and soil; lightning; and, industrial manufacture of fertilizers.

· Plants convert nitrates obtained from soil water into large, nitrogen-containing molecules necessary for life and good health. Animals get most of the nitrogen-containing molecules they need by eating plants or other animals that have eaten plants. When plants and animals die, decomposers break down the nitrogencontaining molecules into ammonia gas and other compounds. Other specialized bacteria convert these into soil nitrates and nitrogen gas which is released to the atmosphere to begin the cycle again.

· Humans intervene in the nitrogen cycle in several important ways:

· Large quantities of Nitrous oxide (NO) and Nitrous dioxide (NO2) are added to the atmosphere when fossil fuels are burned in power plants and vehicles. These nitrogen compounds react with other chemicals in the atmosphere to form smog and acid rain, endangering the health of humans.

· Nitrogen gas and hydrogen gas are converted by an industrial process into ammonia gas and then ammonia compounds used as inorganic fertilizers.

· Mineral deposits of compounds containing nitrates are mined and used as inorganic fertilizers.

· Excess nitrates from different sources (e.g., runoff of animal wastes from livestock feedlots, runoff of, inorganic fertilizers from croplands and discharge of treated and untreated sewage) enter aquatic ecosystems, causing rapid growth of algae, depleting the water of dissolved oxygen gas and causing fish kills. This is known as cultural eutrophication, a process that speeds up the natural ageing of lakes.

Society and the carbon-oxygen cycle

Society and the carbon-oxygen cycle

Society and the carbon-oxygen cycle

· Carbon and oxygen are two of the most important elements needed by all living organisms.

· The cycling of carbon and oxygen is closely tied with energy flows in the ecosystem.

· Through the process of photosynthesis, green plants convert carbon from the air (in the form of carbon dioxide) into plans tissue (carbohydrates).

· In the process of respiration, oxygen is absorbed by living organisms from the environment and is utilized by living cells as an oxidizing agent. Carbohydrates are broken down to carbon dioxide and water and released again to the atmosphere.

· In nature, the processes of photosynthesis and respiration balance each other. For a long period of time, the concentration of oxygen in the atmosphere remained at 2 l percent while the concentration of carbon dioxide stabilized at 0.03 percent.

· Present human activities release increasingly more amounts of carbon dioxide into the atmosphere and the balance between these two gases is upset.

· Burning of fossil fuels in automobiles, power plants and industry has resulted in the release of large quantities of carbon dioxide and carbon monoxide into the atmosphere.

· Large quantities of carbon dioxide are also released when agricultural residues are burned.

· The forest is an important carbon sink. Forest conversion means removal of a large volume of vegetation that can absorb carbon dioxide from the atmosphere and release oxygen through the process of photosynthesis. Burning of forests directly releases carbon into the atmosphere.

· This increased concentration of carbon dioxide in the atmosphere may cause global climate change with potentially great repercussions for all living organisms, especially humans.

Health consequences of environmental degradation

Health consequences of environmental degradation


Beware! Nature is fighting back against the abuses we have inflicted upon it. Environmental crisis has set in our midst. The food we eat, the air we breathe end the wafer we drink contain in varying degrees harmful substances or pollutants. The generation of wastes has surpassed the capacity of the land, water and atmosphere to assimilate them.

There are four types of pollution, namely:

1. Air Pollution - undesirable changes in the physical and chemical characteristics of air. Smoke emissions of industrial plants, motor vehicles, methane gas from waste/refuse combustion make the air unclean.

2. Water Pollution - when water contains more harmful bacteria and poisonous chemicals that it can naturally get rid oft The dumping of domestic and industrial wastes in to water bodies, floods, mine fatlings can pollute our waterways.

2. Land/Soil Pollution - when harmful substances are introduced into the soil making it unable to sustain plant life. Use of excessive chemical fertilizers and pesticides depletes nutrients. hardens the texture, increases toxicity, making the soil less productive.

4. Noise Pollution - too loud, so sudden, persistent and unpleasant sounds that become an assault to the body causing mental or physical harm. The roaring of motor vehicles, grating sound of jackhammer, squeaking tires, blaring TV sets, radios and stereos and even loud shouts are noise pollutants.

There are three major factors that affect environmental health which can be manifested by the correlation between and among human behavior, environmental degradation and human health impacts.

Rapid population growth, urbanization and industrialization

· These changes bring about environmental degradation due to:

· population pressure in the cities and its consequences such as insufficient human settlements, conversion of agricultural land at the fringes of cities into human setllement areas, pollution, overcrowding, poor solid waste disposal, poor sewerage system and water shortage;

· health problems in slum areas mount where basic health services cannot satisfactorily address; and,

· conversion of forests to agriculture and other uses which can increase soil erosion, cause landslides and aggravate floods.

Health consequence of environmental degradation

The common health problems/diseases brought about by pollution are:

Air respiratory diseases like asthma, bronchitis, tonsillitis, common coughs and colds, TB, eye, nose and throat irritation, cancers

Water-borne - gastro-intestinal diseases such as cholera, typhoid fever, dysentery, infections, hepatitis, food poisoning and even death (i.e., mercury deposits in kidneys and brain)

Soil-borne - parasitism, malnutrition, skin diseases end cancers.


· The human health consequences do not affect everyone equally.
· Children are more affected by environmental degradation than adults.
· Similarly, the poor are at greater risk than the rich.
· Adult's negligence of the environment is stealing the right of the young to health.

Population and the environment

Population and the environment

Population and the environment

Humankind has been blessed with vast resources upon which it depends. However, unchecked population growth places tremendous demands on mother nature. An increase in population means an increase in the following needs: food, water, energy, clothing, housing, consumer goods, infrastructure all of which can lead to environmental degradation.

Population data

Table 1. Philippine population and annual growth rates. (1970-1990)


Population rate (in millions)

Growth rates (in percent)


36.7 -






















Source: National Census and Statistics Office Survey

Population Impacts

Sheer Numbers

All of toe more than one million Filipinos being added to the country' s population each year have basic needs for food, energy, housing and other necessities. Fulfilling these needs, even at a minimal level, has an impact on the environment. For example, each person needs an average of 2,350 food calories (car) daily to be healthy and productive. These food calories must be produced from existing land and water resources. Where people rely on wood for fuel, each rural resident needs about 7.5 trees annually for fuelwood, or 75 trees per person in a 10-year planting and harvesting cycle.

Multiplying factors

Each individual's impact on the environment is multiplied by his/her level of consumption of natural resources and the level of technology used to support that level of consumption.


Population growth increases the density of urban and rural human settlements beyond the ability of local ecosystems to renew themselves or to absorb wastes. Concentrations of people can overwhelm municipal services such as water supply, sanitation, housing, energy and transportation. This also contributes to many health problems such as tuberculosis, viral infections and other contagious diseases.

Pace of Change

Many developing countries, like the Philippines, can barely keep up with the increasing demand for food, jobs and housing. The pace has forced people to adopt environmentally damaging production methods. Increasing demand for consumer goods and the rising need to strengthen the economy have brought an era of increasing industrialization and urbanization.

Threshold Effects

Threshold effects can either be biological or economic. Biological thresholds stem from the increasing stress that additional humans place on natural ecosystems. For example, a lake may be able to absorb the sewage of 500 people but will suddenly cease to support plants and fish if the polluting population grows to 505 people. Economic threshold effects can cause dramatic increase in costs. As more people require more food, energy, wafer end minerals, these resources become scarce or less accessible; therefore, raising their prices and requiring continuous search for substitutes.

Global-carrying capacity

Global-carrying capacity is defined as the maximum human population that the earth can support indefinitely on a specific resource base, using a specific level of technology. There are physical limits to the carrying capacity of the earth:

· The finite capacity of natural systems to provide food and energy and to absorb wastes

· The amount of greenhouse gases that accumulate in the atmosphere without triggering irreversible climatic changes

· The amount of fresh water available to support humans, other animals and plants

· Grasslands take a year to grow back after overgrazing.

· Fish stocks may take five years to return to previous levels after moderate overfishing.

· Forest ecosystems may take 20 to 100 years to grow back.

· Topsoil takes hundreds of years to form.

· Aquifers can take between one and thousands of years to refill.

· Ultimately, the issue of how humans and the earth can reconcile their compatible needs remains a big challenge.

Freshwater ecosystems

Freshwater ecosystems

1. Spring/brooks - 2. Ponds/Dams



1. Spring/Brooks

Upwelling and flowing groundwater that usually drains into a catchement area called brooks, e. g., Los Bahot springs; Tiwi Hot Springs; Hidden Valley (Alaminos, Laguna); natural springs

2. Ponds/Dams/Reservoirs

A body of water naturally/artificially impounded for sustainable domestic/fishery, agricultural, industrial uses, e.g.,Angat Dam; Ambuklao Dam and Sta. Mesa Filtering Plant; other fish ponds.

Statistics: 59 dams and reservoirs with a total of about 33,000 hectares.


5. Lakes

Confined static bodies of water where streams and river flow.

Example: Laguna Lake; Taal Lake; Lake Naujan.

Statistics: 70 lakes with a total of 200,000 hectares.

6. Swamplands

Areas of shallow and stagnant water in which conditions are domminated by closely-packed vegetation, often emergent such as trees, palm and weeds.

Example: Candaba Swamp

Estuarine-mudflat ecosystems

Estuarine-mudflat ecosystems



Estuaries are invaluable ecosystems located along the coast where rivers meet the sea. The-mixing of the freshwater from rivers with the salty oceanic waters results in an average salinity lower than that of the open sea.

Together with the mixing of waters is the mixing of sediments from the rivers and from the sea. These sediments are deposited at the mouths of estuaries as mudflats. These flats can stretch along several kilometers of coast, especially where a great number of freshwater streams empty into the sea.

This estuarine-mudflat ecosystem lies near the mangrove forest ecosystem. Usually, there is a gradation from the muddy substrate covered by mangroves to the bare intertidal zone made up of sandflats and mudflats.

Food web

The main food source in the estuarine-mudflat ecosystem is the large quantity of organic material (detritus) coming from the mangrove forest ecosystem and usually deposited with the sediments. Primary consumers, either living on or burrowing in the mud, feed on these organic materials. Examples of these are barnacles, mussels, oysters, polychaetes, oligochaetes, burrowing molluscs and other zooplanktons. Attracted to these numerous and diverse populations present in estuaries and mudflats are secondary consumers such as shore birds, fish and invertebrate predators like crabs, some types of shrimps and carnivorous marine worms.

Other ecological values

· Serve as nursery and breeding grounds of commercially important fish resources.

· Stabilize shoreline.

· Aid in the moderation of water quantity and the purification of water.

Threats to the estuarine-mudflat ecosystem

· Pollution - Estuaries receive all the wastes carried from the land by rivers. The most dangerous of these are the non-biodegradable chemical wastes like heavy metals and pesticides, which can accumulate in the sediments and may enter the food web through the large number of invertebrates. Organic pollutants in great quantities from untreated sewage from human settlements and industrial discharges may deplete oxygen in - the water. Hence, pollution may result in less biodiversity due to death, impairment of reproductive capability and weakened resistance against diseases.

· Reclamation/Conversion - Estuaries are strategic locations for ports, industrial complexes, commercial establishments and human settlements. Reclamation for these purposes and conversion of the estuarinemudflat areas to aquaculture ponds, salt pens and farms will lead to a loss of an ecosystem important as a productive transition zone between rivers, land and sea.

Seagrass ecosystems

Seagrass ecosystems


Seagrasses have distinct physical features and the presence of roots and a vascular system and the ability to flower distinguish seagrasses from other marine plants like the seaweeds.

Found along the coast, supporting the mangroves in the tropics and the marshes in the temperate regions, seagrasses (commonly called isay or lusay) comprise one of the most conspicuous ecosystems of the shore. Thus, they have often been attributed a fundamental ecological importance as well as economic significance. Seagrass ecosystems have several features as shown in the preceding illustration.

From the viewpoint of coastal productivity and protection, the presence of extensive seagrass meadows is favorable. Also, the interaction of some, if not all, of the above factors is responsible for the seagrass bed's function as a spawning, nursery or feeding ground of fishes, shrimps and other animals. However, as human population increases, so does the multiplicity of demands on the marine environment. Since seagrass beds occupy the shallow waters along coastal fringes, they are vulnerable to man's activities (e.g., dredging operations). And once the seagrass cover is lost, it is often difficult to restore.

Sadly, despite this fact, the economic implications of such dependence has not been well documented. Here in the Philippines alone, most studies have been on taxonomy. Perhaps, with the exception of about two or three studies, no other work on Philippine seagrass fisheries has been carried out. One of these was a survey conducted by Estacion and Alcala in 1986. According to that survey, edible mollusks harvested by fishermen in two primarily seagrass beds in Bais Bay, Negros Oriental, included 27 species of bivalves and gastropods.

Other invertebrates collected were holothurians (e.g. trepang) and sea urchins. Both are gathered for food although the first serves as a substantial source of income as well. In fact, this industry has been in existence in the Philippines for years. Then, too, certain medicinal properties are attributed to some species controlling hemorrhage and fungal action and possibly with some tumor-inhibitive potency.

Five species of sea urchins were found common in seagrass beds in the Central Visayas. The most favored for local consumption is Tripneustes gratilla. Its gonads and other soft tissues are usually eaten raw. Sea urchin caviar can be found in local markets. Approximately 1.3 tonnes are harvested per year.

Egg masses of the sea hare, Dolabella curicularia, are also a popular food fare in the region. Anti-cancer agents have been isolated from this organism. Annual harvests are estimated at 1,000-2,000 kg.

Around eight species of juvenile (e.g. Penaeus monodon or sugpo, P. indicus) and three species of adult crustaceans (e.g. Matuta sp., Portunus sp., Thalamita sp.) have been observed.

In additions adults of approximately 50 fish species in 31 families have been been found. Popular food fishes are the carangids, clupeids, lutjanids and scarids. Another survey revealed 64 species of juvenile fishes in 40 families, 33 of which are considered economically important.

Other fauna found in seagrass beds are sea snakes (e.g., Acrochordius granulatus), small fishes like eels, the Green Sea turtle (Chelonia mydas) and the dugong (Dugong dugon) which is considered as an endangered species throughout its range.

To date, there still exists many gaps in our knowledge of seagrass ecosystems. Yet, action must be taken if man hopes to gain the most from this resource. Simply by taking an interest now, aren't you glad that you have taken the first step?

Mangrove ecosystems

Mangrove ecosystems

The mangrove ecosystem is commonly understood to be made up of a collection of woody plant species associated with characteristic fauna and flora and anaerobic soils found in the intertidal zone. They are often referred to as coastal woodland, tidal forest and mangrove forest.

Ecological and economic importance

· Provide food and shelter for a large and varied group of fishes and shellfish. The leaf detritus (fallen and decaying leaves) provides the base of the major mangrove community food chain. The aerial roots provide shelter for many species of commercial fish and shellfish, particularly in their juvenile and most predator prone stages.

· Provide protection from storm surges and high winds associated with tropical typhoons. This is important in a country that is hit by an average of 20 typhoons a year.

· Serve as protection against soil erosion. Soil erosion and sedimentation causes in the ocean is the number one cause of coral reef degradation.

· Serve as land builder through soil accretion. Sediment from the land collects among the dense roots building up the land.

· Trap coastal pollutants which may otherwise severely damage adjacent marine ecosystems.
Serve as wildlife sanctuary.

· Offer aesthetic, educational and scientific values.

· If used on a sustained yield basis (proper harvesting), can provide timber, firewood, charcoal, pulp and paper, extractives, nipa sap, nipa shingles, cellulose xanthate, oil, medicine, resin, tea and livestock supplements.

· Present status of Philippine mangroves

· In 1918, there were 450,000 ha estimated of mangrove areas in the Philippines. Since then, there has been a decreasing trend from 375,020 ha in 1950 (NAMRIA) to only 139,100 ha as of 1988 NFRI). The rate of deforestation averages more than 4,000 ha/year. The decrease in mangrove cover over the years can be attributed to harvesting of mangroves for charcoalor fuelwood production and by forest clearing for fishpond development. As of 1989, a total of 210,681 ha of mangrove forests have been converted to fishponds (BFAR).

Decreasing trend in mangrove cover in the Philippines

Causes of mangrove destruction

· Overexploitation by traditional users.

· Destructive action resulting from activities generally unrelated use of mangroves:

· Commercial timber harvesting

· Conversion of mangrove areas for aquaculture (e.g., fish, shrimp, prawns), agriculture, saltponds and urban development

· Mining/mineral extraction.

How mangroves propagate

Coral reef ecosystems

Coral reef ecosystems

Coral reefs shallow-water, tropical marine ecosystems characterized by a tremendous variety of plants end animals and high primary productivity. Coral reefs are massive deposits of calcium carbonate that have been produced by corals with major additions from calcareous algae and other organisms that secrete calcium carbonate.

Common fauna found in coral reef ecosystems are cnidarians such as jellyfishes, hydroids, soft and hard corals, sea anemones; fishes (including aquarium fishes); fishes); mollusks such as clams, top shells and oysters; echinoderms such es sea cucumbers, sea urchins, brittle stars end starfishes; sponges; reptiles such as sea snakes; and, other miscellaneous invertebrates.


· Coral reefs are the most biologically productive of all natural communities. In fact, a single reef alone may support as many as 3,000 species of corals, fish and shelfish.

· Coral reefs provide an area for recreation and tourism due to its aesthetic appeal, biological richness, clear waters and relative accessibility.

· Coral reefs protect coastal villages by protecting the shoreline and acting as a self-repairing breakwater.

· Coral reefs provide an important source of animal protein. About 30t/km²/year of fish can be harvested in some island fisheries in the Philippines.

Factors favoring reef growth

· Water temperature above 18°C
· Water depth shallower than 50 m
· Constant salinity greater than 30 but less than 36 parts per thousand
· Low sedimentation rates
· Sufficient circulation of pollution-free water
· Pre-existing hard substrate.


Coral reefs are being degraded and destroyed at unprecedented rates, throughout the Philippines. In the 1982 survey, it was found that of the 632 reefs sampled, nearly 70% were found to be in poor to fair condition - having less than 50% live coral cover. As of 1987, more then half of the reefs in the Philippines are in advanced states of destruction, with only about 25 % of live coral cover in good condition and only 5 % in excellent condition.

Dynamite fishing

Cause of destruction

· Increasing population pressure which leads to overexploitation of the resources;

· Sedimentation resulting from human terrestrial activities (unsound agricultural and forestry practices, mismanagement of watersheds, exploitation of mangroves, earth-moving for construction and the dumping of terrestrial and marine mine tailings and effluents);

· Destructive fishing practices (dynamite fishing, muro-ami, dragging nets over reefs, use of small mesh nets and traps, traditional spearing and spearing using scuba);

· Anchor damage by boats caused by inshore fishermen and tourists,

· Pollution due to nearby populated areas;

· Outbreak of crown-of-thorns starfish population which eats stony corals and devastates large areas of reef.

Muro-ami fishing

Heavily damaged coral reef

Human intrusions into the water cycle

Human intrusions into the water cycle

Human intrusions into the water cycle

The water cycle

Water is continually cycling, changing from solid to liquid to gas. Water from soil surfaces, leaves of plants, bodies of water, etc., evaporates as these are treated by the sun. Water vapor in the air condenses to form clouds. When the air becomes saturated with vapor and the temperature goes down, the water vapor falls down the earth's surface as rain, snow, dew or fog. Rain that falls on land infiltrates the soil and is then absorbed by plants and is transpired or evaporated from leaf surfaces. When the soil is saturated, the excess rain may flow on land surfaces as runoff, adding water to creeks, streams, rivers and eventually to the oceans. The heat of the sun propels the continuous water cycle.

Water used for various purposes today is the same water which has been in existence since the beginning of earth. Water cycle interconnects the terrestrial and the aquatic ecosystems. Water cycle is also global in scope. Human actions can reduce the quality of water through pollution and sedimentation. This can seriously affect the environment on which we depend for our existence.

The water cycle

Effects of human activities on the water cycle

Clean water used to be abundant. But it is now becoming a precious commodity.

Human activities have damaged most of our water systems. Improper disposal of sewage, garbage and animal manure has polluted the waterways, rendering the water unfit for human consumption. These pollutants increase the nutrient content of the water and the population of disease-causing germs such as those causing gastro- intestinal disorders. Mine tailings dumped in the rivers cause heavy metal pollution which are suspected causes of cancer and genetic and nervous disorders. Agricultural fertilizers and pesticides that drain into the river system contaminate ground water and enrich the nutrient level of freshwater bodies, eventually killing much aquatic life.

Lower pumping of freshwater near the beach, as in prawn culture, may cause salt water intrusion into the ground water, damaging the source of potable water of a large segment of the population.

Forest destruction in watersheds causes erosion and sedimentation leading to the shallowing of river channels. Forest destruction alters the water cycle.

Heavy rains, strong typhoons and shallow river channels can cause flooding of low lying areas as rivers overflow. This was what happened during the Ormoc tragedy.

Siltation of dams and killing of coral animals in the marine ecosystem are also due to soil erosion carried by flowing waters.

Diversity of coastal and marine resources

Diversity of coastal and marine resources

Philippine marine fisheries

Philippine marine fisheries

Philippine marine fisheries

Major source of livelihood and food

Broadly, marine fishery pertains to the harvesting of the wild populations of marine animals. Philippine waters abound with a variety of marine organisms that are utilized for food and other industries (e.g., marine natural products, shellcraft). Because the country is an archipelago, marine fisheries are the primary source of livelihood in coastal areas. Moreover, fish and shellfish are major sources of protein in the diet of Filipinos. The most commercially important marine animals are: fish, molluscs (e.g., marine snails, mussels, squids); crustaceans (e.g., crabs, lobsters, shrimps) and echinoderms (e.g., sea urchins, sea cucumbers).

Nearshore waters

As in other parts of the world, the major fisheries in the Philippines are concentrated in waters overlying the continental shelf (shallow underwater extension of a continent; usually limited in depth to 200 m). This is because inshore waters have a much higher primary productivity than deep open-ocean waters and, therefore, support larger populations of marine organisms at all trophic levels. Of the total landed fish in the country (approximately 2m tons in 1987), 25 percept come from coral reefs (27,000 km² - total area nationwide) alone. It is estimated that a coral reef in a good condition can annually yield as much as 30 m tons of fish per km². Aside from fish, a majority of benthic (bottom-dwelling) marine invertebrates are harvested from coral reef and adjacent seagrass areas. A wide range of fishing gears are used to harvest the diverse marine resources in these productive and diverse ecosystems.

Declining marine populations and degraded habitats

There has to be a limit to the harvesting of natural populations. A significant fraction of the populations must be left as breeding stocks to replenish the population. Subsequently, juveniles must be allowed to grow to reproductive maturity. Otherwise, natural populations will progressively diminish and may become extinct.

There are clear signs that many of the Philippines' fishery resources are already overexploited. The average size of fish and invertebrates caught by fishermen has declined. Likewise, there is an increase in the fishing effort needed to catch the same amount of fish. The pressure of increased demand for food and poverty due to the rapidly increasing human population promotes the over exploitation of marine resources. Moreover, the degradation of marine habitats due to destructive fishing methods (e.g., blast and cyanide fishing) and sedimentation, particularly in near shore waters, has accelerated the decline of marine fisheries. Appropriate management measures that will allow our overexploited marine populations and degraded habitats to recover need to be urgently implemented.

Marine turtles

The marine turtles are fast disappearing. Once these animals are gone, they are gone forever. Among the reptiles, the turtles are believed to be the longest-living animals. Some species of turtles are known to live for as long as 200 years under normal conditions.

The turtles belong to the Order Chelonia, an order of reptiles over two million years old. They are characterized by a shell that encloses the vital organs of the body. The turtle shell consists of two parts: the carapace covering the back of the turtle and the plastron covering the belly.

Turtles are actually semi-aquatic and marine dwelling reptiles. The Philippines has both freshwater and sea turtles. The hard-shelled terrapins are strictly freshwater dwellers.

Life cycle of a marine turtle

There are three freshwater turtles found in the Philippines, namely the Malayan pond turtle, the Serrated-skelled pond turtle and the Leyte pond turtle.

Five out of the eight known species of marine turtles worldwide are found in the Philippines. These are the Olive Ridley Turtle, the Hawkshill Turtle, the Loggerhead Turtle, the Green Sea Turtle and the Leatherback Turtle.

Species of marine turtles

Sea turtles can be distinguished from their freshwater relatives by their paddle-like legs. They feed mainly on mollusks, fishes, crabs and also marine plants. These marine turtles can be found in the waters of Tawi-Tawi in the Sulu Archipelago, Tubattaha Reef in Palawan and Bantayan Bay in Cebu. They breed in marine waters but go offshore, such as sandy beaches, to lay their eggs.

The largest turtle in the world - the Leatherback Turtle - may be found in Malaysia, Australia and the Philippines. It derived its name from the texture of its skin which is leather-like.

Throughout the world, turtle meat has supplemented the diet of people. Added to this is the demand created to satisfy the cravings of people with exotic taste for turtle eggs and meat.

For many years, marine turtles have also been gathered for their precious shells, being one of the top exports of the Philippines. Today, stuffed turtles are also sold as wall decor and guitars are made from resistant turtle shells. The carapace of the marine turtles are made into combs, brush handles, eyeglass frames, buttons, jewelry and other accessories. Even the turtle hatchlings are being sold as pets. The freshwater turtles are not exempted from exploitation, they are also sold for their meat or as pets.

Products made from marine turtle

Marine food web

Marine food web

Ocean pastures

Ocean pastures

Ocean pastures

Shallow water immediately along the shore looks green in contrast to that several meters away. There, the water turns blue. As one goes deeper, light is absorbed due to the suspended particles. It is absorbed in decreasing order such that less visible colors result; hence, the blue color.

The green places or those which are illuminated by sunlight are the richest in marine life. They teem with minute plants that larger things depend on.

For example, phytoplanktons are eaten by small animals -- zooplanktons. These animals, in turn, are eaten by larger creatures, such as the whale. When different living things depend upon one another in this way, it is called a food chain. And so, as marine animals depend directly or indirectly upon phytoplankton, it is in those areas rich in plant life that most marine animals are found.

But another essential for plant growth is fertilizer. Fertilizers for plants in the sea are known as nutrient salts and two of the most important nutrients are nitrates and phosphates. Nutrient salts come from decomposing bodies or dead plants and animals which have drifted down -to the bottom of the oceans.

The sunlight that marine plants need is at the upper stratum of the water. However, most of the available fertilizers are near the bottom. Plants can thrive only when these two essentials come together.

This happens on shallow banks where sunlight reaches down to the bottom of the water. It can also happen when wind and temperatures changes stir up the water and mix it from top to bottom. This occurs when two currents meet or when a current reaches a land mass. Water is drawn from deep down to the surface carrying with it fresh nutrients into the sunlit water. The regions of great upwellings of nutrients, such as those off the Peruvian coasts, are the sites of the great fisheries.

The menace of algal bloom


Upsetting the ecological balance causes algal blooms

· In natural conditions, relatively small quantities of nutrients and sediments are leached or eroded from the land into waterways. In turn, fed by clear rivers and streams, the natural condition of lakes and estuaries is generally nutrient-poor. This limits the growth of PHYTOPLANKTON (from phyto=plant and plankton = floating) an aquatic plant which consists of numerous species of algae. Algae grow as microscopic, single cells or small groups or threads of cells that maintain themselves near or even on the surface. Since they are not connected to the bottom, populations of phytoplankton must get their nutrients from the water. Lack of nutrients in the water limits their growth accordingly.

· As erosion and leaching occur, a body of water is gradually filled in with sediments and enriched with nutrients. Algal and plant growth steadily increases as the lake shallows and is slowly filled in. This natural ageing process of lakes is called eutrophication.

· Human activities, however, can rapidly speed up this long-term natural process. Logging and agriculture increase sediments and nutrients in runoff flowing into lakes. This speeds up the process of eutrophication leading to large and frequent algal blooms and subsequent fish kills. This human-induced process is known as cultural eutrophication.

· Laguna de Bay is an example of a lake experiencing cultural eutrophication. Industrial, domestic and agricultural wastes all contribute to the pollution of the lake. Siltation from land use, including logging in surrounding hills, has reduced the lakes depth from 7 to 2.8 meters. Algal blooms are becoming more frequent causing larger fish kills.

Red tide (Dynamics and public health aspects)

Red tide (Dynamics and public health aspects)

Red tide (Dynamics and public health aspects)

Red tide refers to the abnormal discoloration of seawater due to the sudden proliferation of microscopic organisms called dinoflagellates. Red tides can be classified into two: toxic and non-toxic. The first nontoxic red tide in the Philippines was recorded in 1908 and was caused by Peridinium sp.; while toxic red tide in the country was first experienced in 1983. Since then, all recorded red tides have been poisonous. Today, more than 1,300 Filipinos have suffered from Paralytic Shellfish Poisoning (PSP). About 71 have died. Most victims were fishermen and their immediate dependents. About 18 provinces have reported red tides since 1983 when the first red tide was documented off the coast of Western Samar. The dinoflagellate causing poisonous red tides in the Philippines is called Pyrodineum bahamense var. compressum. These microorganisms live in coastal waters and lagoons under conditions of high salinity and will not survive in freshwater bodies.

Red tides are found not only in the Philippines but also occur in other parts of the world.

Worldwide distribution of paralytic shellfish poisoning (PSP) - Distribution of PSP in the Philippines

Pyrodineum has seeds found on the muddy bottom of shallow coastal waters. The seeds or cysts are resistant to harsh conditions and may remain viable for 1,000,000 years. Under favorable conditions (e.g., right temperature and amount of nutrients), the seeds can germinate into a free-floating form suspended in seawater. During the day, they are found near the surface where they receive sunlight for their photosynthetic activities. At night, they occur deeper in the water column where they receive nourishment. When conditions change from good to bad, they either die or revert back to their cystic stage.

Sometimes, blooms occur. That is, the dinoflagellates suddenly proliferate rapidly on a massive scale. Possible causes include a change in climate (from prolonged drought to sudden rains) and pollution due to improper disposal of human wastes and bad farming practices. None of these, however, have been proven to be a direct cause of algal blooms. Therefore, scientists are unable to predict red tides.

Tracking the distribution of red tides is very difficult because the bloom tends to move. Red tides are only visible when the algal bloom occurs on the water surface during daytime.

Effects on human health

Dinoflagellates serve as food to shellfish. If a shellfish ingests too much, then the shellfish could possibly contain amounts of the red tide poison lethal to humans. People can get sick after eating seafood products contaminated with the red tide organism. The most common known to cause poisoning are bivalve shellfishes like mussels, oysters; scallops, cockles and limpets. Fish, shrimps, squids, crabs, lobsters and products grown in ponds are generally safe even when caught from red tide-infested waters.

Filter-feeding bivalves affected by red tide

The disease following consumption of contaminated shellfish is called paralytic shellfish poisoning (PSP). Symptoms develop within 12hours following the meal and include tingling or burning sensation in the lips, gums, tongue and face; progressing to the neck, arms, fingertips and toes. Severe cases will suffer from an inability to walk, breathe, swallow and speak and some patients may die from the inability to breathe spontaneously. The poisoning is caused by the neurotoxins from the dinoflagellates which are concentrated by filter-feeding shellfishes. The poison is stable to heat and, therefore, is not destroyed by cooking. It is soluble in water and can be present in shellfish broth. The amount of poison present in shellfish is dependent upon the amount of dinoflagellate filtered by the shellfish. The Philippine standard considers any sample containing 80 micrograms of red tide poison in 100 grams of shellfish meat as dangerous to human health.

There is no known antidote to red tide poison. The best way to avoid the illness is not to eat contaminated shellfish for as long as red tides are present. Patients with mild symptoms can force themselves to vomit to expel the poison from the stomach. Patients with moderate to severe disease must seek medical advice and hospitalization.

Tropical forest -ecosystems

Tropical forest -ecosystems

Tropical forest -ecosystems

Tropical forest ecosystems are situated in the equatorial belt of the earth. This portion of the earth is called the tropical zone. It-accounts for about 40 percent of earth's surface; Within this zone are two major types of tropical forest ecosystems: (1) the rainforest; and, (2) the monsoon or seasonal forest. Both types of forest ecosystems exist in the-Philippines. The latter occupies 6.7. million hectares of the available land area.

The rainforest is one of the oldest and most complex ecosystems on earth.

Extensive rainforest regions

The Amazon River Basin in South America, the Congo River Basin in equatorial Africa and the Malay Archipelago in Southeast Asia.

Philippine forests

Kalinga-Apayao Mountains, Sierra Madre Mts., Palawan, Northern Samar, Mindoro, Agusan, Surigao - del Sur and Bukidnon Mt.

Remaining old growth forest areas in the Philippines

Forest Areas in the Philippines

Types of Forest Area

(m has)










(no data)


(no data)

Adapted from DENR, 1990.

Ecological importance of tropical forests

· Maintenance of a well-balanced local, regional and or global climates. Vegetation can affect-climate in several different ways, via heat balance, surface roughness, the hydrological cycle (precipitation and evapotranspiration) and carbon storage.

· As a living storehouse of biodiversity. Reduction in structural diversity inevitably follows from human interaction with- tropical rainforests as they are progressively simplified by increasing degrees of interference, e.g., timber utilization. The mast deleterious effects would be to see the trees and not the animals or vice versa. Biodiversity has a life-sustaining effect to human beings.

· Natural protection against human impoverishment. Human population located in the tropics depends on the forest resource base for its basic sustenance. The disappearance of the forest through massive disturbances in the forest ecosystem would also mean loss of hut man lives.

Forest ecosystem threats

The direct threets to forest ecosystems in the Philippines are:

Forest conversion

· Logging. It is estimated that fogging activities destroy forests et a rate of 100,000 hectares per year (DENR,

· Subsistence/Permanent Farming. The conversion of forests to other land uses. In 1980 alone, about 210,000 ha were deforested and converted into agricultural land use. This trend is increasing at the rate of 200,000 ha/year.

· Aquaculture. Philippine mangrove forests have decreased in size by 99% since 1920. Mostly due to conversion to aquaculture.

Wildlife trade

· In 1990-91, the Philippines exported about 84,668 heads of mammals, 4,188 heads of birds, 516 heads and specimens of reptiles and 130,775 pieces of orchids and 4,510 pieces of insects.

Other issues and threats

· Watershed Denudation. Nineteen out of 58 major watersheds are critically denuded, reducing their hydroelectric and irrigation potentials, as well as their water regulation functions.

· National Parks. This covers 381,549 has. Only seven out of 77 national parks now meet international standards, due to squatting, illegal logging, kaingin and subdivision.

· Loss of Biodiversity. This is indicated by the fact that our list of endangered species contains 18 entries. Another 25 are in the threatened list. Many of these plants and animals reside in rapidly disappearing forests. 50 percent of our endemic forest flora are already extinct.

Effects and implication

· Physical. Soil is exposed to wing and rain, therefore, increasing erosion. Loss of root structure can cause landslides end crop losses; silt raises riverbeds leading to floods; siltation on inland water bodies end coastal areas; depletion of biotic species inland and in the coastal areas; and, loss of forest biodiversity.

· Sociocultural and Economic. Unemployment; export receipt diminution; degradation of cultural values and norms; development projects are resisted and aborted; dislocated communities (environmental refugees); and, more impoverished workers and upland occupants.

Protected areas: a tool for biological diversity conservation

Protected areas: a tool for biological diversity conservation


1. The Philippines, through-the National Integrated Protected Areas System (NIPAS), has adopted eight categories of protected areas: strict nature reserves, nature parks, natural monuments, wildlife sanctuaries, protected landscapes/seascapes, resource reserves, natural biotic areas and multiple-use areas. These categories represent a range of varying level of human use:

2. Strict Nature Reserves. To protect nature and maintain/natural processes in an undisturbed state. They provide ecologically representative examples of the natural environment and make these areas available for scientific stubby, environmental monitoring and education and for the maintenance of genetic resources in a dynamic and evolutionary state.

3. Nature Parks. - To protect outstanding natural and scenic areas of national or international significance for scientific, educational and recreational use. These are relatively large natural areas not materially altered by human activity and where commercial extractive uses are not permitted.

4. Natural Monuments. To protect and preserve nationally significant natural 'features because of their special interest or unique characteristics. These are relatively small areas focused on protection of specific features.

5. Wildlife Sanctuary. To ensure the natural condition necessary to protect nationally significant species, groups of species, biotic communities or physical features of the environment where these require specific human manipulation for their perpetuation.

6. Protected Landscapes/Seascapes. To maintain nationally significant areas which are characteristic of the harmonious interaction of resident people and land while providing opportunities for public enjoyment ' through recreation and tourism within the normal lifestyle and economic activity of these areas.

7. Resource-Reserve. To protect the natural resources of the area for future designation and prevent or contain development activities that could affect the resource pending the establishment of objectives based on appropriate knowledge and planning.

8. Natural Biotic Area; To foster the way of life of societies living in harmony with the environment to adapt to modern technology at their pace.

9. Multiple-Use Area (i.e., Extractive Reserve? Game Ranch and Recreation Area). To provide for the sustained production of water, timber, wildlife, pasture and outdoor recreation, with the conservation of nature primarily oriented to the system of economic activities.

Benefits of protected :areas

Protected areas provide the following year-round benefits:

· Protect ecosystems essential to maintain life-support cervices, to conserve wild life and to advance scientific research.:

· Protect culturally important landscapes and traditional sites of activities of great significance to indigenous people, including sacred places and historic monuments built on them.

· Protect recreational and educational uses of natural, modified 'end cultivated ecosystems.

· Protect ecologically important areas which, when damaged, endanger public welfare. Example: watersheds.

· Protect species and population that are highly sensitive to human disturbance, those important in medicine and those which enhance the attractiveness of landscapes.

· Protect ecologically important areas

· which, when damaged, endanger public

· welfare.

· Protect the habitats critical to harvested, migratory or threatened species.

· Protected area management

· Management of protected areas is to be done by a protected area management board. The board is madeup of local representatives, DENR officials, NGOs and indigenous cultural communities. Management plans are to be designed using various management zones to regulate activities within the protected area.

Environmental effects of overexploitation for fuelwood in nearshore coastal resources

Environmental effects of overexploitation for fuelwood in nearshore coastal resources

Biological diversity: and wildlife conservation

What is biological diversity?

Biological diversity refers to the variety of life forms found on earth, their genetic-constitution of the - ecosystem and ecological processes of which they are a part. Biological diversity is usually considered at three levels: genetic diversity, species diversity and ecosystem diversity.

Genetic diversity - refers to the sum total of heritable traits/characteristics contained in the genes of each living organism. This diversity is found within species and is the reason why no two individuals are identical

Genetic diversity

Species diversity - refers to all species of plants, animals and microorganisms. This diversity refers to the variety of different species within a given ecosystem.

Species diversity

Ecosystem diversity - refers to the variety of habitats, biotic' communities and ecological processes, as well as to differences in habitat and ecological processes found within each ecosystem. This diversity refers to variation within and among ecosystems.

Ecosystem diversity

What are wildlife?

Wildlife are plants and animals found in their natural habitat undisturbed by man or free from human' interference. They constitute flora (plants) and fauna (animals) not domesticated and which are free-ranging in their naturally associated habitats.

What is wildlife conservation?

Wildlife conservation is action to increase, maintain and protect existing wildlife population for their economic, ecological; scientific, educational and cultural importance. Wildlife conservation programs include the enforcement of the regulation of trade on the Convention on International Trade of Endangered Species of Flora and Fauna. This is achieved through the issuance of permits in the exportation of wild flora and fauna and the enforcement of the regulation against gathering and transporting wildlife- species.

Also included in this process is the capture, banding and release of migratory birds as well as the monitoring of activities of wildlife forms, petshops, nurseries and the status of wild plants.

Value and/or importance of biological diversity

Biological resources provide products which people depend on for health and well-being.


· Economic value. Many wildlife species offer high potentials for saving money and generating income. Food, like fruits of trees, fishes, insects and snails, are sources of protein.

· Biomedical value. Many wildlife species are used for medical researches and formulation of medicines.


· Ecological value. Wildlife plays an important role in the essential life processes that are carried out by nature, Birds, for example, serve as excellent monitors for the environment. 'The presence of certain birds can indicate the health of a given ecosystem. But, if birds are declining in: number and fail to breed successfully, the environment is unhealthy. Birds and insects help in the pollination of flowers and seed dispersal, thus, keeping the environment healthy and productive. Birds of prey keep clown to a desirable level the population of pests and diseases harmful to agricultural crops.

Social and cultural

· Aesthetic and recreational value. Wild plants and animals are sources of inspiration to people, especially to photographers, artists and painters, because of their beauty and wonder.

· Cultural value. Many species of plants and animals are found only in the Philippines. This serves as a source of identity and pride to most indigenous groups. They also serve as a symbol of cultural and national heritage.

· Ethical value. Many people attach feelings of sympathy, responsibility and concern towards wildlife species and the environment. Many argue that all species have their own intrinsic value and, therefore, right to exist.

What are the major threats' to biological diversify?

· Habitat loss or conversion. Related to land use changes that involve great reduction in the area of natural vegetation. This means reduction in the population of species with a resulting loss to genetic diversity and an increase in vulnerability of species and population to diseases, hunting and random population changes.

· Overexploitation. The exploitation of resources at an uncontrolled rate that cannot sustain the natural reproductive capacity of the population being harvested.

· Pollution of air, soil and water. This can lead to the destruction or death of ecosystems and habitats.

· Climatic changes. Alterations in earth's atmosphere 'from human activities may lead to unpredictable changes in climate.

· Introduced species. Non-native species which have replaced the original species of certain plants and animals. Some are responsible for the decline of certain wildlife due to predation, acquired diseases or competition.

· Human population increase. Given a limited resource base, increasing numbers of people result in fewer resources per person and greater waste per unit area.

Wildlife trade

Wildlife trade


What is wildlife trade?

Wildlife trade refers to the collection, purchase and sale of species (plants, animals and marine life) in live or stuffed form, as well as trade in products such as bags, belts, shoes and accessories derived from these organisms.

Why should wildlife trade be regulated?

The uncontrolled trade of plants and animals will leave our country with little or no unique natural resources. Raw corals, which are continually -harvested and sold as house decor, are vital to the country's fishing industry. Some of the orchids which we import at very expensive prices from Thailand were derived from mother plants coming from Philippine forests and yet our very own Waling-waling orchid is fast disappearing

Philippine wildlife trade

Trade of Corals

The high consumer demand for exotic decorative items for the home has given illegal traders the necessary market-for smuggling corals within and out of the country. The USA is the major importer of corals from the Philippines. Corals are made into accessories and other items which are then exported as shell crafts using forged permits.

Trade of Monkeys

Intensified laboratory research has created a high demand for nonhuman primates. The use of monkeys as laboratory animals-is predicted to continue. The demand from zoo and pet trades is also exerting pressure - on the nonhuman primate population. Continuous collection of monkeys for sale abroad beyond natural: replenishment rates will bring about the depletion of the population.

Trade of Birds

Aside from habitat loss, birds are affected by trade and unregulated collection. The big demand-for birds as pets, game, zoo exhibits, or symbols of prestige has contributed to the decrease in numbers of many species;

Trade of Marine Turtles

Marine turtles, one of the most important export animals, have been gathered for their precious shells. Stuffed turtles are highly priced and sold as home decor and guitars. Eggs and meat of sea turtles are considered to be a delicacy and often overharvested.

Trade of Plants

The vegetation in most forest areas is seriously threatened due to wanton destruction. Plants are collected, after being -uprooted from remote and delicate habitats. The unregulated collection 'of these plants, particularly rare and endangered species, is a big problem. Many are in demand and command very high prices here and abroad. Many of the Philippine flowering plants, ferns, orchids; mosses, rattan species and other wild plants have. already been destroyed.

Trade of Reptiles and Amphibians

Many species of crocodiles, snakes, lizards and frogs are traded because their skins are made into bags, belts, wallets and other items. For those who have an appetite for the exotic, the meat of these animals is also eaten.

Trade of Insects

Various kinds of attractive insects, such as Swallowtail butterflies, large beetles, stick insects and leaf insects, are collected in large amounts for mounted specimens and home decor.

Trade of Fishes

The Philippines is renowned for its rich marine tropical fish resources, but the trade is threatened by the indiscriminate use of cyanide. Furthermore, endemic freshwater fishes, like the Sinarapan and the Pygmy Goby, reduced by overexploitation, are now restricted from collection.

What is CITES?:

Although wildlife trade is considered legal in other countries, the recent concern for the conservation of biologic-al diversity has placed restrictions on the trade by virtue of an international treaty. The world's most widely accepted international treaty is the Convention on International Trade of Endangered Species of Wild Flora-and Fauna (CITES). CITES was a world reaction to the global threat posed by the unregulated trade of five specimens, parts or products to the rapid rate of extinction of plants and animals.

CITES is structured to protect endangered species from any commercial exploitation and to subject threatened or similar looking animals to certain control measures (through permits or licenses) before they can be legally traded.

The CITES treaty first came into effect in 1975. In August 1981, the Philippines became asignatory. Since November 1991, the Department of Environment and Natural Resources has been enforcing the treaty. Based on the CITES Agreement, the trade of endangered species, like crocodiles, marine turles and eagles, is banned for collection and export. Trade of other less endangered species like orchids, monkeys and some bird species is allowed but closely monitored.

Climate change and the greenhouse effect

Climate change and the greenhouse effect

· Radiation from the sun passes through the earth's atmosphere to heat the earth.

· Heat radiating from the earth is partially trapped by the atmosphere, keeping the earth warm while some escape into space.

· Increasing concentrations of heat-trapping gases in the atmosphere occur because of human activities.

· The increase in these heat-trapping gases is likely to lead to global climate change which may include:

Temperature rise

· Sea level rise

· Extreme weather.

How deforestation contributes to the greenhouse effect

1. Forests store carbon. In the process of photosynthesis, trees absorb CO2 from the air (along with water, sunlight, nutrients and chlorophyll) and convert it to useable energy and wood. This wood is a sink or storage place for carbon.

Carbon dioxide

2. When forests are cleared and trees burned, carbon dioxide is released into the air.

releasing carbon dioxide into air

3. In addition, termites flourish in places where forests have been burned to make way for farms and cattle ranches. Methane-producing bacteria live in the guts of termites and help to break down the termites' woody food. Methane, released into the air, is a greenhouse gas.


Source: Outreach, Issue No. 56

4. Rice paddies on lands converted from forests produce methane gas which also contributes to the greenhouse effect.

Methane contributes to the greenhouse effect

Acid rain

Acid rain

Acid rain

Normally, rainwater is good for people, forests, crops, rivers and lakes. Rain water is slightly acidic with a pH of 5.6. Acid rain has been occurring for millions of years but with the industrial revolution of the 1 700s and the advent of coal burning, rainwater has become increasingly acidic.

Sulphur dioxide (SO2), Nitrogen dioxide (NO2) and even carbon dioxide (CO2) dissolve in rainwater to form dilute acids.

Acid rain harms trees and crops and upsets the balance of life in lakes and rivers. A lake that becomes too acidic looks crystal cleareven if it is lifeless. First, the aquatic plants are killed. The absence of these plants depletes oxygen sources for fish and amphibians. Acid rain does not kill the forest itself but makes it susceptible to insects and diseases.

Dry deposition: Sometimes, the oxides released into the air do not rise very far into the air, but return to the earth within a few hours and within 190 miles (300 km) or so from their source. These gases or particle fall directly onto the surface of plants, soils, water, etc. This is dry deposition.

Wet deposition: When SO2 and NO2 remain longer in the air, they react with moisture oxygen in the air to form dilute acids. Acid pollutants are carried by the wind for hundreds of miles often across national boundaries and fall to the earth with rain, snow, fog or mist. This is called wet deposition.

Dispersing the problem

Before the 1960's, smoke from industries polluted the nearby environment. In an attempt to improve the living conditions near the industrial plants, taller smokestacks were built. It was thought that the pollutants would be dispersed harmlessly into the atmosphere, but what they did was to create an international acid rain problem.

Dispersing the problem


The ozone layer rests 15 to 30 miles above the earth's surface. It absorbs and deflects 99 percent of the harmful UV rays from the sun. It shields the earth from harmful radiation.


Ozone layer shields the earth from harmful radiation

The ozone layer

The ozone acts as shield from harmful rays of the sun

CFC can destroy the shield

Ozone is a form of oxygen molecule combination with three atoms of oxygen.

The ozone layer rests 15 to 30 miles above the earth's surface. It absorbs and deflects 99 percent from the sun. It shields the earth from harmful radiation.

But the shield can be easily destroyed using CFC'sor chlorofluorocarbons.

CFC is a chemical invented during the 1 930s. It is used as a propellant for spray cans, perfumes and insecticides, air conditioning of cars, houses; and, refrigerator-freezing components use CFCs extensively. It is also used as a cleaning substance for electronics and as a solvent for dry cleaning.

CFC molecule

Other ozone destroyers include bromine containing haloes in fire extinguisher, methane and nitrous oxides and natural elements as volcanic ash and sea sprays.

How does a CFC molecule attack an ozone molecule?

The free chlorine atom goes to seek more ozones to destroy. One chlorine atom is said to be capable of doing permanent damage to 100,000 other ozones.

Cholrine atom

The damaged ozone molecule looks this way: like two idiots.

It is unable to perform any shield task at all and can never repair itself

Scientific researchers indicate that a hole as big as the antarctic continent has already been punched out in the ozone layer.

Hole in ozone layer

How do we repair the damage?
How do we prevent it from worsening?

Toxic and hazardous wastes

Toxic and hazardous wastes


Human activities produce wastes. These wastes accumulate in amounts that may harm the environment and, at sufficiently high concentration, have undesirable effects on plants, animals and man. For example, mining processes contribute heavy metals which may be leached from exposed ores and. waste rocks such as iron, copper, mercury and lead. Factories which change raw materials to finished products produce large amounts of waste products. Industrial operations emit air pollutants like carbon monoxide, oxides of nitrogen, hydrocarbon and lead.

Damage to human health

Examples of toxic wastes affecting human health are numerous:

· Recently, just as the tong-term effects of mercury poisoning in Davao del Norte are being known, disturbing reports indicate that mercury poisoning is spreading to other parts of gold-rush Mindanao.

· In Metro Manila, a World Health Organization (WHO) study revealed that Metro Manilans are exposed to at least 10 times more lead in the air than WHO-prescribed standards. Lead mainly affects the central nervous system, causing fatigue, headache, tremors and convulsion.

· The Department of Agriculture warned residents of Monkayo, Davao del Norte, against eating the meat of animals suspected to have died after drinking from polluted bodies of water. Petrochemical analysis from the Bureau of Mines reported heavy traces of cyanide in water samples.

Important issues


So little is known about the health effects of hazardous wastes that setting exposure levels, in efforts to protect human health, often proves ineffective. Substances coming from wastes vary in their toxicities and produce different toxic effects. This is because they differ in the kinds of chemical reaction they undergo within the biochemical systems. For example, metallic mercury (Hg) is not poisonous. Ingestion of small amounts of mercury, as from a bit of silver amalgam a dentist uses to fill a cavity, is not considered a hazard. But, while metallic mercury is not toxic, its vapors are. Inhalation of enough mercury over a period of time affects the central nervous system, producing symptoms of insanity.

Hazardous Waste Management

Sound management of hazardous wastes is a goal not yet achieved in many countries, even developed ones. Many of the recommended/common ways of waste disposal have been proven to be ineffective and some even pose further hazards. For example, the sanitary landfill has been generally adopted as a substitute for open dumping and burning. Yet, it has been found that, in a sanitary landfill, there is a danger that explosive methane gas and toxic hydrogen sulfide gas, produced by anaerobic decomposition, can build up and explode.

Lack of Data

The lack of data on hazardous waste generation and its effects on health and environment continues to be a major stumbling block, thus hampering proper regulation.

Toxic and dangerous substances and materials that require priority consideration

Arsenic and compounds
Mercury and compounds
Cadmium and compounds
Thailium and compounds
Beryllium and compounds
Chromium(VI) compounds
Lead and compounds
Antimony and compounds
Phenolic compounds
Cyanide compounds
Organohalogenated compounds, excluding inert polymeric materials
Chlorinated solvents
Biocides and phytopharmaceutical substances
Tarry materials from refining and tar residues from distilling
Pharmaceutical compounds
Peroxides, chlorates, perchlorates and azides
Chemical laboratory materials
Selenium and compounds
Tellerium and compounds
Polycyclic aromatic hydrocarbons
Metal carbonyls
Soluble copper compounds
Acids and/or basic substances used in the surface treatment and finishing of metals
Organochlorines (e.g.,PCBs,DDT)

Pollution and long-term effects on the human body

Parts of the body affected by various pollutants


Many different kinds of pollutants affect the human body unknowingly because the chronic (months to years of exposure to the pollutants) are not dramatic compared to the acute (few seconds to days exposure) menaces. The more pronounced acute symptoms are diarrhea, eye and skin irritation, cough and sneezing. Often, by the time clinical symptoms (months to years of exposure to the pollutants) emerge, permanent damage has already been done. Pollutants may also affect the unborn child of a pregnant mother. The effects may appear as abortion, stillbirth and congenital birth defects.

Some pollutants, its long-term effects and the specific organs affected are presented below.



Organs Affected/Effects


Lead battery manufacture


Paint/Smelting industry

Impairment of learning and intelligence in school children

Ingestion of crayons containing lead pigment

Lead encephalopathy (damaged to brain tissue)

Chewing of toys with paint

Mental retardation

Leaded gasoline

Digestive system

Persistent abdominal pain


Bloody urine


Damage to the formation of hemoglobin; joint pains; anemia



Gold extraction from mineral ores


Electrical contacts and vapor lamps

Tremor, loss of memory, lack of, confidence, vague fears and depression


Bloody urine

Oral cavity

Gingivitis (infection of the gums)


Pesticides containing arsenic


Copper smelting

Chronic irritation of the skin

Digestive system

Persistent abdominal cramps, nausea

and vomiting (simple attack)


Chronic irritation/permanent

impairment of vision

Irritant Gases/Asphyxiants

Fumes from smoke-belching cars; emissions from


Sulfur dioxide

industries; cigarette smoke

Aggravation of cardiovascular illnesses


Coal gas industry


Sulfide (H2S)

Gold extraction from mineral ores

Loss of consciousness; impairment of mental function


Fertilizer industry

Aggravation of respiratory diseases (asthma, pneumonia)

Nitrogen dioxide


Carbon dioxide


Carbon monoxide

Reduction of vision

Hydrogen cyanide


Cigarette smoke and

Dusts (vegetable animal)

Cotton fibers


Coffee bean hull

Respiratory tract irritation (cough, sneezing) asthma, pneumonia

Rice hull

Sugarcane bagasse


Animal feathers



Manufacturing, packaging industry


Residues from food

Nervous disorder (paralysis); loss of consciousness

Pesticide from household use

Behavioral disorder (mental disorder)




Chronic allergy


Chest tightness/pain, chronic respiratory tract irritation

Ultraviolet radiation

Destruction of the ozone layer


Prolonged exposure to

Cancer of the skin



Eye impairment (e.g., cataract)


Anti-rust plating material


As salts used as pigments and

Chronic pulmonary irritation

coloring agents for plastics,


ceramics and glass


In nuclear reactors as


absorbing material

Hypertension (High-blood pressure)


Itai-itai disease (softening of the bone associated with pain)


Chronic kidney damage


Geothermal industry


As a component of pesticide

Chronic irritation of the nose and throat

As pigments of white paints.

Pneumonia-like symptoms

Reproductive organs


Impaired female and male

reproductive functions.

Urban pollution: The metro Manila environment

Urban pollution: The metro Manila environment

The environmental problems associated with large cities in developing countries are a result of the high density of human activities, high consumption of resources and generation of wastes and rapid unplanned growth. The combination of these forces leads to high levels of pollution, congestion, crime and health problems. Metro Manila is no exception; with 12,604 people per sq. km., it has the highest population density in the country. The lack of adequate waste disposal has created an unhealthy environment for human habitation.

Mining operations: environmental effects on soil, water, communities and atmosphere

Mining operations: environmental effects on soil, water, communities and atmosphere

Mineral Resource - Nonrenewable chemical element or compound in solid form that is used by humans. Mineral resources are classified as metallic (such as iron and tin) or nonmetallic (such as fossil fuels, sand and salt).

Philippine mineral resources include gold, copper, silver, molybdenum, chromite, iron, lead, zinc, pyrite, ore, coal, sulfur, uranium, etc. They are used in the automobile, housing and other heavy industries. It is one of the country's dollar-earning industry.

Most of the mineral resources are located in mountainous areas, near river systems that support lowland communities and coastal areas. The most common type of mining operation used in the country is the open-pit mining. Extraction of gold, copper and ore, among others


Effects on land/soil

· Mining operations necessitate the removal of green vegetation and the dumping of waste soil. Left alone, mountains will lose their natural barriers against heavy rains with cascading flood waters eroding the top soil, making the surrounding lands ill-suited for crops and trees, rendering them unproductive and lowlands will be vulnerable to flash floods.

· Large areas may be destroyed to massive excavations and removal of large volume of rocks and soil materials. Huge pits will be formed, destroying the aesthetic value of the landscape.

· Occurrences of landslides and mudflows due to the weakening of rocks, accumulation of sand and other debris in mine dams or in natural depressions may lead to great loss of life and property.

Effects on water resources

· Intensive drainage or use of surface and groundwater may cause the drying of streams or the groundwater discharge in springs or outlets of underground rivers.

· Many mineral deposits commonly contain pyrites and other sulphuric-bearing minerals which decompose in water and produce acid water.

· Small-scale gold mining operations have been responsible for mercury pollution in rivers, lakes and seas.

· Heat pollution results when hot waters are drawn to the surface, as in geothermal waters, and are then discharged into surrounding water bodies without initial cooling.

Effects on the communities

· Dumping of tailings has affected lowland populations living downstream. Mine tailings fill streams or river systems and riverbanks are periodically eroded and inundated. Settlements in relatively lowerelevations are subject to frequent flooding, large tracts of farm lands are inundated by mine tailings during typhoons or heavy rains. Tailings are devoid of Nitrogen, Potassium and Phosphorous -- soil elements necessary for normal plant growth and development. Mine tailings contain toxic substances directly inimical to sea life and indirectly to humans.

· Mine tailings caused the filling of certain bays and have been responsible for the siltation and consequent death of some coral reefs, adversely affecting the fish catch of fisherfolk.

· The accumulation of waste rocks and tailing occupies large areas formerly used for agriculture and forestry, purposes.

· Mining expansion and pollution have dislocated many people from their farms, forcing them to migrate to other areas.

Effects on air

· Pollution of the air occurs during mining, smelting and refining. Pollution takes the form of dust or total suspended particulates (TSP), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen oxides (NOx) and hydrocarbons (HC). Toxic emissions cover large areas affecting the health of people.

· Acid rain results from the interaction between sulphur dioxide emissions from smelters fed with sulphides of copper, lead, zinc and other metals and rainwater. This type of pollution is responsible for the destruction of some crops and forests, the pollution of lakes and negative effect on the health of people.

Pesticides: environmental and health effects

Pesticides: environmental and health effects


Pesticides are any substance or mixture of substances used to prevent, destroy, repel or mitigate insects, rodents, nematodes, fungi, weeds and/or other organisms perceived to be troublesome (pest). Its use continues to be an essential and growing component of modern crop technologies. Also, there are several pesticides that are being used at the household level to repel or kill rats, mosquitoes and cockroaches.

However, pesticides pose health and environmental hazards, as has been documented. Worldwide statistics showed that there is a conservative estimate of two million cases of pesticide poisoning last year wherein four percent of this led to death. The problem of underreporting is noticeable because of the lack of knowledge and awareness on signs and symptoms of pesticide poisoning.

Unsafe, indiscriminate and irrational use of pesticides constitute the following:

· regular use of pesticides even when unnecessary;
· not wearing the appropriate protective clothing;
· improper storage, preparation, application and disposal of pesticides and used clothings; and,
· use of pesticides in cocktail or mixtures.

The effects of the indiscriminate use of pesticides can lead to ecological disruption. Among the effects are as follows:

· contamination of ground and surface waters; thus, killing aquatic life forms through runoff and seepage (environmental contamination);

· transmittal of pesticide residues through the food chain to the farm family and urban consumers (biological magnification);

· increase in the resistance of pest population to pesticides (resistance development); thereby, reducing efficacy and causing pest outbreak (pest succession);

· reduction in the population of beneficial insects (butterflies, spiders), parasites (earthworms) and predators; and,

· reduction in the population of microorganisms in the paddy soil and water that help sustain soil fertility while lowering chemical fertilizer use.

The effects of irrational and unsafe use of pesticides on health can lead to any of the following:

· acute poisoning (may occur from single exposure to the pesticide) which is manifested by skin and eye irritation, manifested as cough, colds and shortness of breath) respiratory tract irritation, systemic poisoning and, in some cases, death; and,

· chronic poisoning (results from months or years of continual exposure to pesticides) which can lead to nervous disorders (paralysis, numbness extremities, loss of consciousness), neurobehavioral effects (mental deterioration), anemia, sterility, birth defects and effects on the unborn (manifested as abortions, stillbirths). Chronic poisoning is also suspected to cause cancer of the lungs, brain, blood, digestive system and liver, as well as decreased body's immune system or defenses.

Because of the noted environmental and health effects of pesticides, there are several of them that have already been banned from the market. Among these are the famous DIRTY DOZEN which include Parathion, 2,4,5-T, Paraquat, DDT, Aldrin/Dieldrin/Endrin, Chlordimeform, Dibromochloropropane (DBCP), Chlordane/Heptachlor, HCH/Lindane, Ethylene dibromide, Camphechlor and Pentachlorophenyl (PCP). Organotins (Brestan and Aquatin) were also banned from the market recently.

Philippine commercial energy sources, 1990

Nonrenewable sources

Renewable sources


Nonrenewable energy sources




- Oil-based power plants can be

- Air pollution.

built near end-user sites.

- Contributes significantly to the build

- Relatively shorter time to build compared to other conventional power plants.

up of greenhouse gases, especially CO2.

- Mainly imported and represents huge drain on foreign currency reserves.

Sourcing by Region (1990)

Local (Palawan) 2 %

Middle East 80 %

Asia 17 %

Other regions 1%

- Price and supply are affected by events in oil-producing countries.


- Commercially significant deposits exist in the country.

- Air pollution; contributor of CO2, one of the greenhouse gases and also of sulfur dioxide, SO2, which is a contributor to acid rain.

- Water pollution.

a. Potential for foreign currency savings.

- Coal mining, especially through the open-pit type, is environmentally destructive.

b. Reduced impact of adverse developments in the global energy market.

- Coal mining presents serious occupational health hazards.

- Low quality of most local deposits (subbituminous and lignite):

- Coal deposits in the country are dispersed leading to high transport costs.


- Requires relatively little land for the- amount of energy derived.

- Thermal pollution.

- Discounting leaks and accidents, does not contribute to air and water pollution.

- Disposal of radioactive wastes remains a big issue.

- Catastropic consequences in case of an accident.

- Requires huge capital investments.

- Dependence on foreign technologists.

- Dependence on imported enriched uranium.

Natural gas

- Cleaner burning, i.e., less- polluting, compared to the other fossil fuels.

- Although natural gas has been found in the country, this energy source has not been exploited. Doing so may require large initial investments.

Renewable energy sources


- Significant reserves available in the country.

- Destruction of forests; clearing of large tracts of land:

- Foreign currency savings.

a. Loss of wildlife habitat.

- Minimal pollution

b. Displacement of local populace.

- Lessens impact of adverse

- Huge capital investment.

Developments in the global energy market.


- Non-polluting.

- Huge capital investments.


- No fuel costs; foreign currency savings.

- Submersion of large tracts of land; alteration of hydrological features of vast areas:

- Lessens impact of adverse developments in the global

a. loss of wildlife habitat: end,

energy market.

b. displacement of local populace.

- Dams aid the spread of water-borne diseases, such as malaria and schistosomiasis.

Mini and micro

- Non-polluting.

- High initial costs in local or community level terms.


- No displacement of local populace.

- Technical skills required to build such plants are not available locally.

- Lesser impact on hydrology.

- Can be built on a scale more

appropriate to the requirements

of end users.

- Feasible alternative to areas

not served by regular power



- Utilizes wastes which would otherwise contribute to disposal and pollution problems.

- Supply and collection of materials limit the viability to local levels.

- Foreign currency savings (13 percent of Philippine energy consumption are now met by biomass.)

bagasse, rice, husks, straw, etc.

- Locally feasible in areas where materials are abundant.

- Competes with other uses such as fertilizer.

- Collection may be a problem.

- Burning contributes to the build-up of greenhouse gases.

- biogas

- Clean-burning; non-polluting.

- High initial cost in household-level

- Slurry may be used as organic



- Requires a not inconsiderable amount of maintenance.

- Requires a sufficient number of animals in one or several nearby sites or else collection of manure may be a problem.


- Still widely available in most rural areas although shortages are being felt in some.

- Contributes to de forestation especially mangroves and in areas with rapid population.

- Burning adds to the build-up of the greenhouse gases.

- Replanting required.

Note: Fuelwood is also a biomass energy resource although, because of its special importance, it is discussed separately. Some studies have estimated that as much as 70 percent of Philippine households use fuelwood to some extent.


- Minimal operating expense; no fuel cost

- High initial cost in local or community level terms.

- Non-polluting.

- Can be tapped practically in all rural areas (and unshaded urban areas), especially in isolated places which are not reached by regular power lines.


- Minimal operating expenses; no fuel cost.

- High initial cost in local or community Ievel terms.

- Non-polluting.

- Feasible only in areas where wind

- May be feasible in areas isolated from regular power lines.

factors are favorable.

Common property resources in crisis

Common property resources in crisis

Common property resources (CPRs)

Are those non-exclusive resources in which a group of people have co-equal use, rights and coownership. They are designated as such either on the nature of the resource or on the nature of their usage.

CPRs are divided into three broad categories:

· Land Resources like forests, grazing lands, public lands, wastelands.
· Water Resources like streams, ponds, lakes, groundwater, oceans, seas.
· Air, Sunlight and Space or indivisible natural resources.

CPRs have cultural, social, political and historical bases. Designating a resource as a CPR mainly depends on the existence of a group of people who are residents or indigenous to the area, bound by tradition, formal and informal structures and norms through which they control, own, manage, protect and preserve these resources.

To differentiate CPRs from public and private resources, public resources are those which are exclusively owned, controlled and managed by the government; while private resources are those which are exclusively owned, controlled and managed by an individual or group of individuals. Open access is the term used to describe unregulated use of communally, publicly or privately held property and resources.

CPRs: Roles, function and contribution

CPRs perform a major role as a life support system. In developing countries like the Philippines, CPRs are a significant component of the resource base of rural and urban communities. They contribute to the production and consumption needs of the people in these communities, as well as beyond.

Physical products are obtained directly and indirectly from CPRs: food, timber, fuel, water, manure, fiber, animal feed and clothing.

Income and employment are generated from and provided out of CPRs, particularly for rural communities around them. CPRs are used for activities such as handicrafts production as well as in growing crops and rearing livestock. CPRs are valuable as sources of food sustenance during the drought period.

Larger social and ecological benefits. When properly managed, CPRs ensure the sustainability of agro-ecological systems providing basic needs and sustenance for the poor. CPRs also provide an improved microclimate environment in surrounding communities.

CPRs in crisis

Degradation of CPRs as manifested by their fast pace of shrinkage in area and decline in productivity has resulted in making the poor people who depend on them even poorer. Although efforts by government, private groups and communities to restore, manage and protect CPRs have been started in some areas in the country, the crisis is still real. One factor that contributes to the degradation of CPRs is that the people who manage them are not clear about their roles and rights to the resources. Poor people continue to depend on these dwindling CPRs. And the cycle of poverty and common property resources degradation continues.

Degradation of the uplands

Degradation of the uplands



In the Philippines, the definition of upland areas varies across sectors depending on the government agency or the kind of project involved. The Department of Environment and Natural Resources (DENR) which has jurisdiction over most upland areas in the country uses the following definition:

"Uplands are hilly to mountainous landscape greater than 18 percent including the table land and plateaus lying at higher elevations which are not normally suited to wet rice unless some form of terracing and ground water exists. These are mainly classified as public land."

Ecological significance of upland areas

The upland areas play a significant role in the dynamic and highly interactive landscape components of a rural system. They serve as the life support system of the lowland and aquatic areas. Upland areas are of considerable importance because they contain the tropical forest ecosystems which are the oldest, the most productive and the most protective ecosystems on earth. An increasing population of the "poorest of the poor" lives in the upland areas. These upland areas are expected to absorb even more of the expanding population from the lowlands.

If environmental and socioeconomic conditions in the uplands are not improved, the peace and order situation could worsen. But, properly developed upland areas can be keys to a sustainable, socioeconomic progress for the country.

In the past, upland areas were covered with tropical rainforest vegetation and human population was sparsely distributed. Few problems existed in these upland areas. Upland areas yielded varied products which satisfied the basic needs of these human settlements. However, given an increasing human population, together with indiscriminate exploitation of the forest, the uplands have become marginal and less capable of sustaining productivity and supporting the basic needs of human society (Sajise, 1986).

As forest resources have been depleted and agricultural activities have been undertaken in upland areas, the fragile soil resources have been exploited and severe degradation of upland agricultural land has occurred.

Today, areas affected by agricultural degradation are characterized by barren denuded hills and mountains with very few remaining trees and mainly vegetated with cogon and brush. The soil is not fertile with outcropping of rocks and the presence of eroded gullies. Wild animals are losing their habitat; instead, ruminant animals graze these lands.

Factors affecting degradation of upland areas

· Uncontrolled exploitation of forest, e.g., overlogging, charcoal-making
· Shifting cultivation or "kaingin"
· Population pressure
· Overgrazing
· Improper agricultural practices, e.g., (plowing) down the slope, lack of crop rotations
· Construction of road networks
· Mining
· Land clearing for geothermal infrastructures
· Large forest/grass fires.

Effects of degradation of upland area

· Loss of forest cover
· Soil erosion
· Loss of nutrients (shortened fallow period of land resources)
· Decreased agricultural crop yields
· Flood intensification
· Drought intensification
· Decline in genetic diversity
· Shift in climatic patterns
· Lowered water table
· Increased sedimentation/siltation
· Degradation of coral reefs due to sedimentation originating from upland erosion
· Loss of wildlife habitat
· Increased carbon dioxide level in the atmosphere.

Upland population

Estimated to be 17.8 million Filipinos

- 8.5 million live in the forest
- 5.95 million tribal Filipinos
- 3.35 million lowland migrants

The marginal upland areas include the following classes of areas:

Cultivated/Open areas/Forest

- 0.3040 m. ha.


- 1.8129 m. ha.

Cultivated Mixed Grassland

- 10.1143 m. ha.

Eroded Areas

- 0.0007 m. ha.

Other Barren Areas

- 0.0103 m. ha.


12.2422 m. ha.

Lowland degradation

Lowland degradation


Lowland is any area of rainfed or irrigated farmland that is flat or gently undulating and usually at an altitude not far above sea level. (Resource Book on Sustainable Agriculture for the Lowlands, IIRR, 1990.)

In the Philippine context, most of the lowlands are planted to rice, the staple food of more than 80 percent of the Filipino people. Hence, the lowlands are invariably equated to rice production areas. Of the total rice area, 43 percent is irrigated, 43 percent is rainfed and 12 percent is upland.

Do you know that...

The widespread adoption of the world-renowned Green Revolution, from 1965 to 1988,changed rice farming in the Philippines. These changes were:

· Double rice cropping increased from 19 to 50 percent.
· Adoption of HYV's increased to 87 percent of the total rice-growing areas.
· Fertilizer application increased from 20 to 80 kg/ha.
· Use of insecticide increased from 31 to 94 percent.
· Use of herbicide increased from 12 to 74 percent.
· Use of power tiller increased from 0 to 46 percent.

(Resource Book on Sustainable Agriculture for the Lowlands, IIRR, 1990.)

Other changes which are less readily quantifiable, but equally important in the overall quality of life of the lowland farmers, include:

· Shift to intensive monocropping or the planting of one crop only - rice

· Loss of natural protein foods, e.g., fish, snails and frogs brought about by the heavy usage of pesticides in the farm

· Resistance of pests to chemical pesticides

· Environmental degradation, such as reduction in the natural fertility of the soil (low organic matter), pollution of water sources and effects of pesticides on human health

· Drought and floods

· Sedimentation in irrigation canals

· Some areas are utilized as improperly designed garbage disposal sites.

· Conversion of fertile agricultural land to nonagricultural purposes, such as housing projects and industrial sites.

· Conversion of wetlands to agriculture or other purposes.

Environmental issues in animal production

· There is a limit to the carrying capacity of land to sustain the food and habitat requirements of livestock and farm animals. It is easy to befoul the natural environment through intensive animal production straining already depleted resources.

· Ruminants, e.g., cattle, carabaos, goats, sheeps, etc., can make use of large quantities of low-grade forage and agricultural by-products and thus do not need to compete with humans for grain resources.

· There are four issues associated with intensive animal production:

Waste disposal can lead to pollution

Toxic residue

Genetic manipulation


The four environmental issues related to intensive animal production

1. Waste Disposal

Solid and liquid waste, if not handled expediently and properly, will create pollution and health problems. Nitrogen from animal wastes can seep into aquifers or natural ground water reservoirs and contaminate wells and community water supplies.

2. Toxic Residues

Substances like animal drugs (antibiotics - e.g., sulfadrugs and feed additives, pesticides, environmental contaminants and other carcinogenic substances) used in sustaining intensive animal production systems are known to cause or are suspected to cause hazards to human health (cancer, birth defects, reduced fertility, reproduction defects, neurotoxicity and other toxic effects).

3. Genetic Manipulation

Intensive animal methods have an adverse impact on the health and well-being of animals themselves. Through a combination of genetics and environmental manipulation, intensive production of animals has become possible. Unfortunately, selection of one set of traits is attained only at the expense, neglect and underdevelopment of other clusters of traits which may be equally important in the total performance of an animal breed.

Genetic uniformity makes entire animal farming systems vulnerable to unpredictable changes in the biophysical and social environments.

Reliance on row crops as major source of livestock feeds contributes to soil erosion and overuse of inputs for soil fertility and pest control.

Intensive animal systems neglect the potentials of native animals that can grow under harsh conditions and can survive on low quality and homegrown feeds.

4. Overgrazing

Insufficient fodder, especially during dry periods and droughts, forces animals to forage on available fodder growing in the distant grazing areas. Overgrazing on the earth's natural cover contributes to land degradation and soil erosion.

Massive herding of animals creates gullies that contribute to soil erosion, soil compaction, marching of wetlands and dust storms in dry, windy areas.

Free grazing of animals destroys both less-valued and high-valued grass, crops, plants and trees that can lead to loss of various plant resources.

Plant genetic resources

Plant genetic resources are traits or characteristics, passed from generation to generation through inheritance, that are actually or potentially useful. For each disappearing plant species, up to 30 animal or insect species directly or indirectly dependent upon it may also be lost. If plants do not exist, animals cannot survive.

Plant genetic resources

Uses of plant genetic resources

· Provide humanity with basic needs like food, medicine, shelter, clothing, fertilizer, religious articrafts, fiber, income, craft materials, energy, feed for animals, etc.

· Provide plant breeders materials needed to produce new plant strains/breeds to adapt to a changing environment.

Examples of plant diversity in the Philippines

· The Philippines, a country located in the humid tropics, is one of the richest sources of plant diversity.

· The Tagalog folk song Bahay Kubo mentions a total of 18 vegetables grown around a Filipino backyard.

· Mt. Makiling in Laguna contains more plant species, approximately 3,000, than the entire country of Canada.

· Before the advent of the Green Revolution, there were approximately 3,000 traditional rice varieties found in the Philippines. In 1987, there are only about 100 traditional rice varieties that remain in scattered areas in the Philippines.

· The Hanunoos, a small tribal group in Oriental Mindoro, cultivate at least 21 traditional rice varieties.

· There are at least 100 distinct accessions of cassava (introduced in the country several centuries ago so they have already been acclimatized) found at the Philippine Root Crops and Training Center in Baybay, Leyte.

Threats to plant genetic resources

· Habitat destruction -- the replacement of entire habitats by human settlements, grazing lands, commercial/agricultural lands and industrialization.


As of 1988, there were only 6.5 million hectares of forest area compared to 1969 wherein there were 10.5 million hectares of forest.

Habitat destruction

  • Overexploitation -- the intensive harvesting of plants and the extent to which these plants or plant products are traded.


The export of cycads, orchids, cacti, other succulents and ferns is a major threat to plant genetic resources.


· Agricultural development - the introduction of new breeds of plants (e.g., hybrids) and monoculture production systems.


In the Philippines, 4,000 varieties of rice were planted every cropping season in 1964. Today, only eight major varieties of rice are planted in 8, percent of irrigated rice lands.

Agricultural development

Effects and consequences of the loss of diversity of plant genetic resources

· Tungro virus destroyed JR-8 (a rice variety developed by the International Rice Research Institute) in 1971 and has become prevalent in many areas where IR seeds are planted in the Philippines. This is due to monocropping of IR seeds.

· The abundance of one type of crop (monocropping) results in the proliferation of pests, forcing farmers to use chemical pesticides. However, pests easily acquire resistance to chemical pesticides. In 1 93O, only 30 pests had resistance to chemical pesticides; by 1 980, over 430 pests had acquired resistance to chemical pesticides.

Natural hazards

Natural hazards

Natural hazards become disasters when the disruptions exceed the adjustment capacity of a community. This section describes three major natural disasters encountered in the Philippines: earthquakes, volcanoes and typhoons.


The earthquake that struck Luzon Island last July 16, 1990, at 4:16 p.m. was due to a break in the solid layer of the earth. The biggest shock was felt at Nueva Ecija, Tarlac, Pangasinan, Baguio, La Union and part of Nueva Viscaya. The Office of Civil Defense, Department of National Defense, estimated that about 1,666 people were killed and some 3,561 injured. Most injuries were sustained by people who were hit by falling objects. Many deaths occurred during escape.


Three things are emitted from volcanoes: projectiles, ashfall and lava or lahar. Projectiles can destroy infrastructure and harm people depending on the speed and size of the projectile. Ashfall has always been a source of anxiety among evacuees although the negative effects on health have generally been exaggerated. Residents nearer the eruption are actually more vulnerable to projectiles while those further away are more affected by finer ashfall materials which could enter the respiratory tract, potentially causing lung diseases. Injuries indirectly caused by ashfall occur when heavily-laden roof-tops collapse after a heavy rain. The effects of lava (molten rock) or lahar (volcanic mudflow) are almost similar. Both destroy communities by the property of mass impact or by blocking river channels, then causing flash floods. Lava has the property of intense heat and burns anything alone its path.

Tropical cyclones: depression, storms and typhoons

The impact of these calamities are due to their wind velocity or their potential to cause floods. For example, the destructive effect from wind was the main impact of Typhoon Ruping in 1990. On the other hand, the thousands of people killed in Ormoc City, Leyte, in 1991 was due to a flash flood brought about by a tropical storm. An average of 19 tropical cyclones enter the Philippine area of responsibility though only a small percentage of these are classified as destructive. The most common cause of injury during these calamities is drowning.

Frequency of tropical cyclone passage over each geographical zone in the Philippines.