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新疆阿克苏地区盐化潮土盐分组成为硫酸钙类型。具有面积大,连片分布的特点。虽然盐分具有一定的表聚性,但表聚程度较弱。从盐化潮土在阿克苏地区的分布,盐分在土壤剖面的分以及塔里木河流域水资源合理利用的角度而言当地通过种稻洗盐改良盐化潮土的作法是不合理的。 相似文献
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Because of the human exploitation and utilization of water resources in the Tarim Basin,the water resources consumption has changed from mainly natural ecosystem to artificial oasisecosystem, and the environment has changed correspondingly. The basic changes are: desertifi-cation and oasis development coexist, both "the human being advance and the desert retreat" and"the desert advance and the human being retreat" coexist, but the latter is dominant. In the upperreaches, water volume drawing to irrigated agricultural areas has increased, artificial oases havebeen enlarging and moving from the deltas in the lower reaches of many rivers to the piedmontplains. In the middle and lower reaches of the Tarim River, the stream flow has decreased, old oa-ses have declined, natural vegetations have been degenerating, desertification has been enlarging,and the environment has deteriorated. The transition regions, which consist of forestlands, grass-lands and waters between the desert and the oases, have been decreasing continuously, theirshelter function to the oases has been weakened, and the desert is threatening the oases seri-ously. 相似文献
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