中国科学家在沿海省份大面积试验用海水灌溉农作物,以供养众多的人口,这些人口面临土地匮乏、淡水短缺的压力。早在20世纪90年代,在沿海地区(包括山东省,河北省,广东省和海南省)的近300,000公顷的盐碱地和滩涂上,种的不是小麦、水稻,就是油料作物,这在全世

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问题     中国科学家在沿海省份大面积试验用海水灌溉农作物,以供养众多的人口,这些人口面临土地匮乏、淡水短缺的压力。早在20世纪90年代,在沿海地区(包括山东省,河北省,广东省和海南省)的近300,000公顷的盐碱地和滩涂上,种的不是小麦、水稻,就是油料作物,这在全世界都是不曾有过的。人们相信,发展海水灌溉农业是增加农田和降低灌溉费用的有效途径。中国人口占世界总人口的五分之一,而可利用的耕地面积只占世界总耕地面积的7%。另一方面,海水灌溉对中国这样一个人均淡水占有量只占世界人均淡水占有量四分之一的国家,将大有裨益。自古以来,几乎所有的农作物都得用淡水灌溉。然而,随着杂交技术和基因技术的发展,中国的科学家培育出了一组能在盐碱环境中生长的盐土植物。
【关键词】
盐碱地alkaline land滩涂mudflat杂交crossbreeding
盐土植物halophytes

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答案Chinese scientists tried to irrigate crops with sea-water in massive scale in the coastal provinces in order to feed numerous people there who are threatened with scarce farmland and shortage of fresh water. But as early as 1990s, it was unprecedented in the world that people planted wheat, rice or oil-bearing crops on the alkaline land and mudflat of nearly 300,000 hectares in the coastal regions including Shandong province, Hebei province, Guangdong province and Hainan province. People believe that it is effective to develop seawater irrigated agriculture so as to increase farmland while decrease the irrigation fee. Chinese population is one fifth of world population while cultivated land is only 7 percent of the world’s sum total. Otherwise, the seawater irrigation can greatly benefit China where the a-mount of fresh water per capita is only one fourth of the figure per capita worldwide. Since ancient times, nearly all the crops are irrigated with fresh water. However, as crossbreeding and gene technology develop, Chinese scientists have cultivated one type of crops that can grow in the alkaline land—halophytes.

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