Water use and availability in the river basins of the Challenge Program on Water and Food

[摘要] We use water-use accounts to develop a synthesis of water availability and use from the Indo-Gangetic Basin, the basins of the Karkheh, Limpopo, Mekong, Niger, Nile, São Francisco, Volta, and Yellow River basins. We also examine the water availability per head of population, currently and in the future, based on the projected population to 2050. We examine, at a coarse resolution, the spatial and temporal variation in water availability and use.The basins have a wide range of climate characteristics from wet to dry, and from those with considerable year-to-year variability in rainfall to those with less. The Mekong and Ganges are the wettest basins with about 1500 and 1200 mm annual rain respectively, while the Karkheh (about 400 mm), Yellow (400) and Limpopo (550) are the driest basins. The basins are all highly seasonal, with distinct wet and dry seasons. The rainfall leads to runoff and river flow which is also highly seasonal.Water use varies greatly amongst basins. The drier basins (Volta and Limpopo in particular) show a dominance in water use by grassland, shrubland and barren land. Irrigation is important in the Indus, Ganges, Karkheh and Yellow River. The year-to-year variation of irrigation diversions is less than the variation in rainfall and runoff – which is to be expected, since that is the purpose of irrigation water resource management. The water availability per head is large in the Mekong and San Francisco, and least in the Limpopo. The Limpopo, Volta and Niger have very low availability per head in the dry season. Water availability per head will decrease with population growth in all basins, dramatically so in the case of the Niger, Nile and Volta.

[发布日期] 2012-03-22 [发布机构] CSIRO

[学科分类] 地球科学(综合)