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Environment has taken rather a back seat politically since the Earth summit in Rio de Janeiro nearly five years ago. 【C1】______the problems that meeting【C2】______had not gone a-way. One environment【C3】______tank—the International Food Policy Research Institute—has been looking at the future of water and【C4】______report reflects growing concern at the huge leap in usage over the past few years. In some parts of the world, water consumption has【C5】______five fold. And the institute, known by its【C6】______ says shortages could soon become the【C7】______for conflict and a major barrier to【C8】______the world's growing population. Here's Richard Black of our Science Unit. It's often been said that water【C9】______oil will be the cause of warfare in the next century. According to the IFPRI report, the time【C10】______that happens might not be far away. The number of people【C11】______by water shortages will increase ten【C12】______over the next 30 years, it says, 【C13】______could well lead to large scale conflicts. The main reason why water is becoming a【C14】______resource is agriculture, which now【C15】______70% of water consumption worldwide, 90% in some【C16】______countries. Countless farmers have switched from growing indigenous crops for the【C17】______market to high yield export varieties, which【C18】______need far more water. But the IFPRI report says that in some regions water shortage is now the single biggest impediment to feeding the population. Water scarcity【C19】______leads to water pollution. In the Indian State of West Bengal, for example, over extraction of water from boreholes has led to arsenic poisoning which is【C20】______to have affected two million people so far. But the IFPRI report calls for better water management worldwide including financial incentives to encourage conservation.