The United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Sites are places of importance to cultural or natural heritage as described in the 1972 UNESCO World Heritage Convention. The sites of natural and cultural heritage in Madagascar became eligible for inclusion on the list when that state ratified the convention on July 19, 1983.
The first site in Madagascar, the Strict Nature Reserve of the Tsingy of Bemaraha, was inscribed on the list as a site of natural importance at the 14th Session of the World Heritage Committee, held in Banff, Canada in 1990. This was followed by the 2001 inscription of the Royal Hill of Ambohimanga, a historic village and royal palace compound of cultural importance featuring well-preserved 19th-century palaces and numerous other natural and architectural features of historic, political and spiritual significance to the Malagasy people. Most recently, in 2007 the natural site of the Rainforests of the Atsinanana was added to the list, comprising a cluster of six national parks distinguished by their highly endemic biodiversity. A fourth site, the capital of the 19th century Merina sovereigns of Madagascar at the Rova of Antananarivo, had originally been slated to become the nation's first cultural World Heritage Site in 1995 but was destroyed by a fire shortly before the inscription was finalized.
Erosion is the process by which soil and rock are removed from the Earth's surface by exogenetic processes such as wind or water flow, and then transported and deposited in other locations.
While erosion is a natural process, human activities have increased by 10-40 times the rate at which erosion is occurring globally. Excessive erosion causes problems such as desertification, decreases in agricultural productivity due to land degradation, sedimentation of waterways, and ecological collapse due to loss of the nutrient rich upper soil layers. Water and wind erosion are now the two primary causes of land degradation; combined, they are responsible for 84% of degraded acreage, making excessive erosion one of the most significant global environmental problems.
Industrial agriculture, deforestation, roads, anthropogenic climate change and urban sprawl are amongst the most significant human activities in regard to their effect on stimulating erosion. However, there are many available alternative land use practices that can curtail or limit erosion, such as terrace-building, no-till agriculture, and revegetation of denuded soils.