B 3.1. What impact do sugarcane crops and ethanol production have on the availability of water in Brazil?
Although Brazil has the worlds largest water supply, with 14% of its surface water and the equivalent in annual runoff in underground aquifers, agricultural irrigation as a whole is not much used (~3.3 million hectares, out of 227 million hectares in the world). Sugarcane in Brazil is practically not irrigated, except in small areas where it is used as a supplement. This is an enormous advantage over other regions of the world. Consequently environmental problems over water quality caused by irrigation (the seeping of nutrients and agrochemicals, erosion) and its industrial use are considerably less common than in other parts of the world. Brazils environmental agency, EMBRAPA, classifies sugarcane as Level 1 (no impact on water quality). In the ethanol and sugar industries levels of water collection and release have been substantially reduced in recent years: from around 5 m3 per ton of sugarcane (in 1990 and 1997), to 1.83 m3 per ton of sugarcane in 2004 (in So Paulo). The efficiency
