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机构地区:[1]黑龙江农垦勘测设计研究院,黑龙江哈尔滨150090
出 处:《农业系统科学与综合研究》2011年第3期382-384,共3页System Sciemces and Comprehensive Studies In Agriculture
摘 要:东北黑土区是全世界仅有三大块黑土区之一,黑土土质疏松,有机质含量丰富,是最为肥沃的耕作土壤,有"土中王"之称,是大自然赋予人类的得天独厚的宝藏。近二三百年来,随着人类不合理的开发利用,珍贵的黑土层正以每年剥蚀0.3 cm^1.0 cm的速度流失。目前黑土区坡耕地黑土层厚度已由开垦初期平均80 cm^100 cm降到20 cm^30 cm。按照现有的侵蚀速率和防治进度推算,40 a^50 a后大部分黑土层将流失殆尽,对区域生态环境及社会经济的可持续发展造成严重危害。Black soil region in Northeast is one of three large black area in the world,Loose black soil,Rich in organic matter content,Is the most fertile farming soil,The "king of the earth," said,Nature gives human beings unique treasures.Past two to three hundred years,With the irrational exploitation and utilization,Precious black soil,at an annual rate of erosion loss of 0.3 ~ 1.0cm.Currently black soil farmland cultivated black soil layer has been reduced to the initial average of 80 ~ 100cm to 20 ~ 30cm.In accordance with the existing rate and control the progress of erosion projections,40 to 50 years will have been depleted of most of the black soil,On the regional ecological environment and sustainable development of socio-economic causes serious harm.
分 类 号:S157[农业科学—土壤学] S155.27[农业科学—农业基础科学]
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