Sri Lanka's principal environmental problem has been rapid deforestation, leading to soil erosion, destruction of wildlife habitats, and reduction of water flow. In 1985, the total amount of land affected by deforestation was 224 sq mi. The government began a reforestation program in 1970, and since 1977, it has banned the export of timber and the felling of forests at elevations over 1,500 m (5,000 ft) and the export of timber. Nevertheless, between 1981 and 1985, some 58,000 hectares (143,000 acres) of forestland were lost each year and the nation lost an additional 21.4% of its forest and woodland between 1983 and 1993.
The nation's water has been polluted by industrial, agricultural, and mining by-products along with untreated sewage. As a result, only 70% of the people living in rural areas have pure water. Air pollution from industry and transportation vehicles is another significant environmental concern. The main environmental agency is the Central Environmental Authority within the Ministry of Industry and Scientific Affairs. Although legislation to protect flora and fauna and to conserve forests has been enacted, there has been inadequate enforcement of the laws, and the nation's wildlife population has been reduced by poaching.
Wildlife has been protected since 1937; by 2001, protected areas covered about 13.3% of the country's total land area. As of 2001, 14 of Sri Lanka's mammal species and 11 of its bird species are endangered. Endangered species include the Asian elephant, green labeo, spotted loach, and four species of turtle (green sea, hawksbill, olive ridley, and leatherback). In addition, 431 types of plants are threatened with extinction.