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中国农学通报 ›› 2015, Vol. 31 ›› Issue (23): 162-170.doi: 10.11924/j.issn.1000-6850.casb15010246

• 资源 环境 生态 土壤 气象 • 上一篇    下一篇

退耕政策对延安地区土壤侵蚀影响

王 涛,雷 刚,刘郁丛,孟 欣,张振鹏,吴 同,吴亚颜   

  1. 西安科技大学测绘科学与技术学院,西安科技大学测绘科学与技术学院,西安科技大学测绘科学与技术学院,西安科技大学测绘科学与技术学院,西安科技大学测绘科学与技术学院,西安科技大学测绘科学与技术学院,西安科技大学测绘科学与技术学院
  • 收稿日期:2015-01-31 修回日期:2015-07-06 接受日期:2015-03-25 出版日期:2015-08-20 发布日期:2015-08-20
  • 通讯作者: 王 涛
  • 基金资助:
    国家自然科学基金项目“生态脆弱区土地集约利用模拟研究”(41271103);西安科技大学博士启动基金项目“气候变化和人类活动影响下土地利用变化环境效应与模拟研究”(2012QDJ029);西安科技大学培育基金项目“多尺度土壤侵蚀人为影响机制研究”(2014007)。

Influence of Grain for Green Policy on Soil Erosion in Yan’ an Area

  • Received:2015-01-31 Revised:2015-07-06 Accepted:2015-03-25 Online:2015-08-20 Published:2015-08-20

摘要: 陕北黄土高原是中国土壤侵蚀最为严重及退耕政策实施的重要区域,经过10多年退耕还林还草政策实施,区域生态环境明显改善。科学评价政策实施对土壤侵蚀的影响,有助于政策的调整及完善。以延安地区为例,基于该区域土地利用、植被覆盖、DEM及降水等数据,评价退耕政策实施对区域内土壤侵蚀的影响。结果表明:(1)受退耕政策影响,2000—2010年延安地区及>25°区域耕地面积大幅减少,主要转化为草地和林地,转化比例分别超过80%和15%;(2)>25°区域耕地面积减少207.8km2,减少47.50%,但仅占延安地区退耕面积的8.8%,由于>25°区域耕地对土壤侵蚀影响较大,完全可以全部实施退耕;(3)退耕政策实施提高了植被平均NDVI值,延安地区及>25°区域,耕地减少区域的植被平均NDVI值在2000—2010年间分别增加53.76%和55.29%;(4)计算表明,2000—2010年间耕地面积减少并未抵消降雨侵蚀力增大对土壤侵蚀的影响,若按2000年降雨侵蚀力不变计算,退耕政策确实起到了减少土壤侵蚀的作用。由于土壤侵蚀的减少是一个长期过程,所以退耕政策实施成果的维护、植被覆盖的改善和恢复需要持续进行。

关键词: 蓖麻, 蓖麻, 基因组, Mlo, 基因家族, 序列分析

Abstract: Loess Plateau of northern Shaanxi Province is an important soil erosion area and Grain for Green Policy (GGP) implementation area in China. After 10 years implementation of the policy, the regional ecological environment has been improved obviously. Scientific evaluation of GGP’ s influence on soil erosion is helpful to the adjustment and improvement of this policy. The author took Yan’an area as an example, evaluated GGP’ s influence on soil erosion based on land use data, MODIS NDVI, DEM and precipitation data. The results showed that: (1) influenced by the implementation of GGP from 2000 to 2010, farmland in the area of Yan’ an and >25° farmland significantly decreased, mainly converted to grassland and woodland and the conversion ratios were over 80% and 15%, respectively; (2) >25° farmland in the area decreased 207.8 km2, reduced by 47.50%, but only accounted for 8.8% of total returning farmland area in Yan’ an; >25° farmland should be all returned due to its important role in soil erosion; (3) the implementation of GGP increased average NDVI value, the NDVI value of Yan’ an area and >25° area increased by 53.76% and 55.29% from 2000 to 2010, respectively; (4) the reduced area of farmland in 2000 to 2010 did not offset the soil erosion caused by the increase of rainfall erosivity. GGP really played an important role in reducing soil erosion calculated by rainfall erosivity in 2000. Since soil erosion reduction is a long process, the author suggested maintaining the GGP achievement, and continuing the improvement and recovery of vegetation.