II. ENVIRONMENTAL IMPLICATIONS OF UNSUSTAINABLE DEVELOPMENT
A. Major green environmental problems and causes
Forests are a renewable resource. But once natural forest cover has been cut it is very difficult, and sometimes impossible to revive the original natural ecosystem. There was a time when the majority of NWFP was covered with forest and natural vegetation. However, much of that forest cover has gone and the affected areas are seriously degraded, with exposed rock showing in most of the hilly areas and whole ecosystems completely changed.
In theory, the whole of NWFP plains area should be under tropical thorn forest (Champion, Seth, and Khattak, 1965), with dry subtropical broad-leaf forest on the drier foothills, moist and dry temperate forests on the mid-mountain areas, and sub-alpine forests at the highest elevations of vegetative cover. However, the tropical thorn forests have been destroyed mainly as a result of the conversion of land for agricultural purposes, combined with grazing and cutting of woody vegetation for fuel. The remaining types of forest have been reduced to a fraction of their original extent, mainly as a result of heavy uncontrolled grazing, tree felling and agricultural cultivation on mountain slopes.
The process of deforestation has been greatly intensified during the past century through the rapid increase in human and livestock populations. The data on forests and deforestation in NWFP are contentious. Agricultural statistics for Pakistan indicate that the forest area was 1.33 million ha in 1992, following a 53 per cent increase from 1982 to 1991. That increase was thought to be the result of the reforestation programme. The forestry sector master plan estimates the total area under forest and cultivated trees to be 1.68 million ha. While preparing for the Forest Development Project in the Siran valley, GTZ (1990) compared Landsat MSS data for 1979 and 1985, and Landsat TM data for 1988 on the Siran and Agror-Tanawal Forest Divisions. The comparison revealed that the forest area had declined by 12.8 per cent from 1985 to 1988. It is unclear what caused the annual depletion rate to accelerate from 1.8 per cent recorded during 1979-1985. The Forest Department gives high priority to forest conservation, but despite all its efforts the tremendous pressure caused by high timber prices and fuelwood demand makes it extremely difficult to save the forests. It is generally perceived that the Forest Department and fire hazards are the main threats to the forests.