Amazonia: Water Resources and Sustainability

Abstract

Water resources in Amazonia affect all natural and human-altered ecosystems in the region, including their human populations. Evapotranspiration by the Amazon forest provides water vapor that is transported by wind to other regions of Brazil and to neighboring countries. The enormous quantities of water involved in hydrological processes in Amazonia give great importance to the region’s water resources and to potential impacts if these cycles are altered. The diversity of fish and other aquatic organisms is enormous, as is the importance of this fauna as economic and food resources for the human population. There are impacts from pollution, including mercury methylation in hydroelectric reservoirs. Dams also block migration of fish and alter the flooding cycles of rivers. Hydroelectric dams release methane, thereby contributing to global warming. The chemical characteristics of different types of water affect processes such as the transport of organic carbon, the supply of nutrients to the plankton that are the base of the food chain in aquatic ecosystems, and the quantity of bio-available ions that affect sensitivity of organisms to copper and other toxic elements. Several of the major rivers in the region drain more than one country, as is the case for the Madeira River, whose basin drains parts of Bolivia and Peru, in addition to Brazil. International treaties require protecting the rights of other countries that share aquatic resources in trans-border watersheds. The hydroelectric dams under construction in Brazil on the Madeira River imply a variety of impacts in the neighboring countries, including blocking the migration of large catfish. One of the priorities for rational decision making on aquatic resources in Amazonia is expansion of scientific knowledge on aquatic systems in the region. A series of national and international projects are engaged in improving this knowledge, and masters and PhD programs are increasing the capacity for research in the area. The human population in the region depends on the functioning of aquatic ecosystems. People share the fate of these ecosystems, in which they constitute a central component.