|Basic Concepts in Environment, Agriculture and Natural Resources Management: An Information Kit (IIRR, 1993, 151 p.)|
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
· Improper agricultural practices, e.g., (plowing) down the slope, lack of crop rotations
· Construction of road networks
· 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.
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:
- 0.3040 m. ha.
- 1.8129 m. ha.
Cultivated Mixed Grassland
- 10.1143 m. ha.
- 0.0007 m. ha.
Other Barren Areas
- 0.0103 m. ha.
12.2422 m. ha.