![]() | Basic Concepts in Environment, Agriculture and Natural Resources Management: An Information Kit (IIRR, 1993, 151 p.) |
![]() | ![]() | 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) |
Dipterocarps |
2.435 |
Mossy/marginal |
0.2455 |
Mangroves |
0.1494 |
Pines |
0.0812 |
Beach |
(no data) |
Molave |
(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 DIYERSITY-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
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
· 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
· 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.