|Soil and Water Conservation (SWC) Technologies and Agroforestry Systems (IIRR, 1992, 171 p.)|
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 landscapes with 18 percent slope or greater, including the table land and plateaus lying at higher elevations which are not normally suited to wet rice unless some from the terracing and ground water exist. These are mainly classified as public lands.
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 rainforest 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 areas are expected to absorb even more of the expanding population from the lowlands.
In the past, upland areas were covered with tropical rainforest vegetation and human population was sparely 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 practically do not exist; instead, ruminant animals graze these lands.
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.
DEGRADATION OF THE UPLANDS
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 compose the following classes of areas:
- 0.3040 m. ha.
- 1.8129 m. ha.
Cultivated Mixed Grassland
- 10.1143 m. ha.
- 0.0007 m. ha.
Other Barren Areas
- 0.0130 m. ha.
12.2422 m. ha.
FACTORS AFFECTING DEGRADATION OF UPLAND AREAS
Land tenure arrangements
Uncontrolled exploitation of forest, e.g over-logging, charcoal-making
Shifting cultivation or"kaingin"
Speculation/Conversion of agricultural lands
Improper agricultural practices, e.g., (plowing) down the slope, lack of crop rotations
Inefficient use of forest products
Construction of road networks
Land clearing for national infrastructures (dams, geothemmal plants)
Large forest/grass fires, indiscriminate burning
Land conversion in the upland li.e., for residential lands)
EFFECTS OF DEGRADATION OF UPLAND AREA
Loss of forest cover
Loss of nutrients (shortened fallow period of land resources)
Decreased agricultural yields
Reduced efficiency of hydroelectric projects
Decline in genetic diversity
Shift in climatic patterns
Lowered water table
Salt water intrusion to wafer table in coastal areas
Loss of wildlife habitat
Increased carbon dioxide level in the atmosphere (global wamming)
Increased poverty of famm families
Urban migration of salty water into terrestial bodies