2. 职称英语
  3. 中国试验海水灌溉农业 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，这些人口土地面临匮乏、淡水短缺的压力。早在20世纪90年代，

中国试验海水灌溉农业 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，这些人口土地面临匮乏、淡水短缺的压力。早在20世纪90年代，

游客2023-12-28  15
问题    中国试验海水灌溉农业
   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，这些人口土地面临匮乏、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30万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。正好一举两得，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百分之七。假如所有的可利用土地都用来种植农作物，那么可以生产出一亿五千万吨农产品，大约相当于中国30％的年产量。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四分之一的国家，将大有裨益。中国的农业用水量占总用水量的70％，而60％的耕地灌溉用水严重缺乏。与把海水变成淡水的技术成本相比，直接将海水引入运河或直接在盐碱土壤上种植农作物的费用只有前者的1／30。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。运用克隆或“花粉管道”等特殊技术，中国科学院的科学家们成功地将耐盐作物遗传物质导人普通茄子、辣椒，培育出了能在滩涂中生长的特殊品种。
   迄今为止，试验在大量种植小麦和水稻的地区顺利推行，从东部的黄河三角洲延伸至南方的珠江三角洲。过去的五年里，中国农业发展迅速，但中国政府仍然把调整农业结构，提高农民收入，保证农产品质量作为工作重心。中国政府认为，科学和技术将是发展国民经济包括农业在内的关键。既然技术瓶颈已被攻克，中国很有可能在21世纪大范围推行海水灌溉农业。
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答案    China Experiments with Seawater-irrigated Agriculture
   Chinese scientists are experimenting on irrigating crops with seawater in vast areas of coastal provinces, in an effort to help feed its huge population bothered by a shortage of land and fresh water. Since the early 1990s, almost 300, 000 hectares of alkaline land and mudflat stretching along the country’s coastline, covering Shandong, Hebei, Guangdong and Hainan provinces, have been planted with either wheat, rice or oil crops, which is unprecedented around the world. Like killing two birds with one stone, developing seawater-irrigated agriculture is believed to be a way to create more farmland and lower irrigation cost.
   China’s population accounts for one-fifth of the world’s total, but it only has about 7% of the world’s arable land. If all that extra land can be used for planting crops, 150 million tons of agricultural products could be yielded, about 30 percent of China’s yearly output. In another aspect, seawater irrigation can mean a lot for China whose per capita possession of fresh water equals only about one-fourth of the world’s average. Water consumption for agricultural use in China accounts for 70 percent of the nation’s total, and 60 percent of the cultivated land is desperately short of water supply. Compared with the technique to turn seawater into fresh water, it would cost only one-thirtieth of the cost to bring seawater directly through canals or to plant crops directly in saline soil. Since ancient times, almost all agricultural plants have to be irrigated with fresh water. However, with crossbreeding and gene techniques, Chinese scientists have cultivated a group of halophytes capable of living in a saline environment. Employing special techniques like cloning or " pollen canal technique" , scientists of the Chinese Academy of Sciences successfully induced a hereditary element of halophytes into eggplants and peppers, and produced special species that can grow in a mudflat.
   So far, the experiment is moving forward smoothly from the Yellow River Delta in east China to the Pearl River Delta in south China, where wheat and rice are growing in abundance. During the past five years, Chinese agriculture has witnessed marked progress, but the Chinese government still regards it as a major priority to readjust the agricultural structure, increase farmers’ income and insure food safety. Science and technology, the Chinese government believed, will be the keystone for progress in the national economy including agriculture. Now that the technical bottleneck has been conquered, China is very likely to use land irrigated with seawater on a vast scale in the 21st century.
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