Water Resources Heedless exploitation of depletable groundwater supplies endangers food production and other essential human systems. Heavy demands on the world's surface waters have resulted in serious shortages in some 80 countries, containing 40 percent of the world's population. Pollution of rivers, lakes, and groundwater further limits the supply. Oceans Destructive pressure on the oceans is severe, particularly in the coastal regions, which produce most of the world's food fish. The total marine catch is now at or above the estimated maximum sustainable yield.
Some fisheries have already show signs of collapse.
Soil Loss of soil productivity, which is causing extensive land abandonment, is a widespread by-product of current practices in agriculture and animal husbandry. Forests Tropical rain forests, as well as tropical and temperate dry forests, are being destroyed rapidly. At present rates, some critical forest types will be gone in a few years, and most of the tropical rain forest will be gone before the end of the next century. With them will go large numbers of plant and animal species. The irreversible loss of species, which by 2100 may reach one-third of all species now living, is especially serious.