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1 序言当今世界正处于环境时代,人们都非常关心自己周围的环境。近年来,人类的活动能力过分增强,使环境受到各种方式的破坏,其结果威胁着未来人们的生存。不仅陆地、大气已处于危险状态,水域也已受到威胁。目前全世界的人口以每年900万人的速度增加,同时,由于耕地的盐碱化、过剩化肥和有害化学物质的污染、灌溉用水的不足,地下水层的下降,造成耕地的沙漠化或气候异常,其结果是每年粮
1 Introduction Today’s world is in an age of environment where people are very concerned about the environment around them. In recent years, human activities have been excessively enhanced in capacity to undermine the environment in various ways, with the result threatening the future survival of people. Not only the land, the atmosphere is already in danger, the waters have also been threatened. At present, the population of the world is increasing at the rate of 9 million people each year. At the same time, due to the salinization of cultivated land, the pollution of excess fertilizers and harmful chemical substances, the shortage of irrigation water and the decline of groundwater layer, desertification or climate anomaly in cultivated land is caused, The result is annual food