ABSTRACT
Water is a renewable resource, unequal geographic distribution of water and pollution that makes water unusable can cause freshwater shortages. This chapter shows that, in many areas, water use is unsustainable. Most water use in the agricultural sector is consumptive, since more than 50" of the water withdrawn from freshwater sources is lost to the atmosphere by plant transpiration and by evaporation from reservoirs and irrigated fields, leaving little for other uses. Water is required for the production of all agricultural products and most commercial products. According to The Living Planet Report, the water footprint of a country is the total volume of water used to produce all of the goods and services consumed by its inhabitants. In the United States, the largest use of freshwater is for energy production. The availability of fresh water is primarily determined by the amount of precipitation and temperature.
