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Effect of land-use and land-cover ch

時(shí)間:2023-05-02 14:06:23 生物醫(yī)學(xué)論文 我要投稿
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Effect of land-use and land-cover change on nutrients in soil in Bashang area, China

The Bashang area is a water-source area and ecological barrier zone for Beijing and Tianjin. The area is located at 200 km fromBeijing and Tianjin and is a typical agriculture-pasture-interlacing zone, in which the eco-environment is vulnerable and hence it is sensitive toenvironmental change. The area is relatively lagged in social and economic development, where the traditional cultivation mode is predominatedin agriculture and animal husbandry, but the disturbance by human activity is relatively small. Therefore, in order to reveal the interrelationbetween eco-environmental change in the area and environmental change in Beijing and Tianjin area, it is fairly necessary to study the effect ofland-use and land-cover change on nutrients in soil in this area. According to the actual situation of changed land use for the limited timeperiod, five series of changed land plots were selected and 4 samples were collected from each series for the study. The samples were collectedfrom different soil-forming levels at the same site in different time. Analysis of the collected samples indicates that in the process of change ofland use and land cover, the nutrients in soil, such as organic matter, total N, total P, total K, and available N, P, K, and B, Mo, Mn,Zn, Cu, and Fe, have regularly changed. When the land had changed from grassland and non-irrigated farmland into woodland, and from non-irrigated farmland into irrigated field, the nutrients in soil totally increased. But there exists some exception, i.e. quick-acting N, P, K, andsome microelements have appeared to be inconsistent with the mentioned above regularity in some cases.

作 者: SHENG Xue-bin SUN Jian-zhong Liu Yun-xia   作者單位: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China  刊 名: 環(huán)境科學(xué)學(xué)報(bào)(英文版)  ISTIC SCI 英文刊名: JOURNAL OF ENVIRONMENTAL SCIENCES  年,卷(期): 2003 15(4)  分類號(hào): Q149  關(guān)鍵詞: Bashang area   land use change   variation of nutrients  

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