The chief environmental problem in the densely populated Altiplano is soil erosion, resulting from poor cultivation methods (including slash-and-burn agriculture) and overgrazing. Erosion currently affects 30% of the land in Bolivia. Salinity and alkalinization are also a significant problem. Inadequate sanitation and solid-waste disposal, as well as effluents from mining activities, contribute to the Altiplano's declining water quality, which poses a threat both to fish life and to human health. Bolivians have 316 cu km of renewable water resources, but only 95% of the city dwellers and 64% of all rural people have pure water. The main sources of water pollution are fertilizers, pesticides, and mining. Most environmental legislation dates from the 1970s, when Bolivia enacted the Health Code of 1978 (which contains provisions governing water quality), the National General Forest Act of 1974, and the Law of Wildlife, National Parks, Hunting, and Fishing (Decree Law No. 12,301) of 1975.
In July 1987, the Bolivian government became the first government in history to agree to protect a part of its environment in return for a reduction of its foreign debt, when Conservation International, a US nonprofit group, purchased $650,000 of the debt in return for Bolivia setting aside 1.5 million hectares (3.7 million acres) of tropical lowlands in three conservation areas. As of 2001, 14.2% of Bolivia's total land area was protected. The Department of Science and Technology, within the Ministry of Planning and Coordination, plans and coordinates all governmental and intergovernmental activities related to the environment.
Endangered species in Bolivia include the puna rhea, South American river turtle, broad-nosed caiman, spectacled caiman, black caiman, jaguar, jaguarundi, margay, ocelot, emperor tamarin, and giant anteater. The llama and the alpaca are also threatened with extinction. In 2001, out of a total of 316 mammal species, 24 were considered endangered. There were 27 species of birds and 3 species of reptiles that were also threatened. Of 18,000-plus plant species, 107 were in danger of extinction.