highland plateau, a massive transformation occurred that eliminated virtually all the heavily forested vegetation in the period 1970 to 2000. The slash and burn agriculture eliminated about ten percent of the total country's native biomass and converted it to a barren wasteland. These effects were from overpopulation and the necessity to feed poor indigenous peoples, but the adverse effects included widespread gully erosion that in turn produced heavily silted rivers that "run red" decades after the deforestation. This eliminated a large amount of usable fresh water and also destroyed much of the riverine ecosystems of several large west-flowing rivers. Several fish species have been driven to the edge of extinction and some, such as the disturbed coral reef formations in the Indian Ocean, are effectively lost. Nigeria With approximately 199 million people, 86% of Nigerians don't have access to a safe source of drinking water. UNICEF reports that over half of the basic water services for 70% of Nigerians are contaminated. Lack of infrastructure throughout Nigeria prevents most communities from having clean water; a typical Nigerian gets only 9 L of water on average each day. Because of this, many Nigerians depend on commercially available water such as sachet water (see picture) or bottled water. Polluted and contaminated groundwater supplies contribute to water scarcity in Nigeria. Some major categories of pollutants include fertilizer and agricultural runoff, poor sewage management systems, industrial waste, oil and gas contaminants, mineral mining by-products, and abattoir effluent. See also 2007 African floods 2009 West Africa floods Atmospheric water generator Water crisis in the Democratic Republic of the Congo Water in Africa Water issues in developing countries Water politics Water security References External links Webdossier Water in Africa (2012) International Decade for Action "Water for Life" 2005-2015 Water in Africa Water conservation A Articles containing video clips