Central and South America is the most biologically diverse continent of the world. It includes temperate and tropical forests, high-altitude desert plateau, glacial peaks, freshwater and saltwater wetlands and coral reefs. While some areas remain relatively untouched by humans, others have been decimated by rapid urban growth, large-scale agriculture and mining.
The largest and best-known area under threat is the Amazon rainforest, home to several million species of plants, animals (including 3,000 species of fish) and micro-organisms, many still unrecorded by science. Many of these species are confined to small areas and are sensitive to environmental change so are at a high risk of becoming extinct with the destruction of their habitat.
The region’s indigenous peoples historically lived by hunting, gathering and subsistence farming, mostly in small isolated tribes. Cattle ranching, mining and the timber industry were brought to the region by Europeans. Initially, settlement was restricted to the banks of the navigable rivers, still the principal means of transport, but roads are increasingly being built across the forest, some of them by the government, but most of them illegally, by developers.
The extent of the loss of rainforest habitat is difficult to assess in this huge, impenetrable area. The Brazilian National Institute of Space Research estimated deforestation between 2003 and 2004 to be 10,500 square miles (27,300 sq km). Although the annual rate declined in subsequent years, there were worrying signs, early in 2008, of an increase. In addition, mining activities and the effluent it produces, which can contain mercury, has severely polluted parts of the Amazon River.
Attempts are being made by governments, non-governmental organizations such as the WWF, Conservation International, university teams around the world, and wealthy individuals to protect parts of the remaining forest. One such scheme, the Amazon Region Protected Areas (ARPA) program, was set up in 2003 by WWF, the World Bank and the German Development Bank in collaboration with the Brazilian government, It aims to establish 109,000 square miles (283,000 sq km) of new protected areas and transform existing but neglected parks through a system of well-managed protected areas and sustainably managed reserves. At the same time as the Brazilian government is supporting such measures, however, it is pressing ahead with an infrastructure program that includes the development of roads through the rainforest, railways and dams, all of which will increase the rate at which vital habitat is lost.
The financial value of the rainforest is huge. Not only is it a source of potentially life-saving natural products that can be used in pharmaceuticals, but its vital function as a huge carbon store gives Brazil the opportunity to sell “carbon credits” to organizations unwilling to reduce their emissions of carbon dioxide. Its ecological value is immeasurable, and its loss could lead to a catastrophic increase in the rate of climate change.
Important ecological areas do not fit neatly within political boundaries, and conservation projects are increasingly seeking co-operation between countries. In Central America, for example, where there are more than 400 protected areas, efforts are being made to establish a “Mesoamerican biological corridor” that integrates the efforts of eight countries. And although other forest and mountain areas are now fairly well protected, it is recognized that more needs to be done to conserve the region’s wetlands, such as the Pantanal, and its coastal and marine areas. Natural World Heritage Sites have been established throughout the continent, and include a wide range of habitats. International co-operation is not always so forthcoming. Attempts to protect the biologically rich mountainous Cordillera del Condor region in South America, for example, have been hampered by a border dispute between Ecuador and Peru.
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