小流域植被覆盖与工程措施因子遥感监测研究

目的]通过对长江委丹江治理工程重点项目区西河小流域植被覆盖与工程措施因子(CP)进行遥感监测研究,为丹江流域以及长江上游地区水土流失定量检测、土壤侵蚀综合防治和评价提供科学的决策依据。方法]利用2010年丹江流域商南县西河小流域环境小卫星遥感数据,采用Erdas软件对遥感数据进行处理,得到影像中各类地物植被覆盖度。利用卜兆宏等水土流失定量遥感监测模型(QRSM模型)植被因子与植被覆盖度关系式算法,即用土壤流失量遥感监测植被因子算式开展计算和分析。结果]西河小流域北部治理区和南部山区植被覆盖和工程措施因子值相当低;在河道两岸有局部区域出现了植被覆盖与工程措施因子高值区,主要是由于该区域居民房屋建筑和道路建设破坏了植被;中部人口集中的区域,治理程度较低,仅有较少区域出现植被覆盖集中连片高值区。结论]影响水土流失众多客观自然因素中植被覆盖因子的影响最大,另一方面,人类过度开发利用土地资源引起陆地生态系统发生变化,因此研究水土流失应综合考虑地理、自然和经济发展,因地制宜,合理规划,确保经济持续稳定发展和生态安全。

Remote Sensing Monitoring of Vegetation Cover and Engineering Measure Factors of Small Watershed

Objective] The remote sensing monitoring research of vegetation cover and engineering factor(CP) in the important engineering projects of Yangtze River Committee on Xihe catchment of the Danjiang basin was conducted to provide scientific basis of comprehensive control and evaluation based on quantitative monitoring of water loss and soil erosion in the Danjiang River basin and the upper reaches of the Yangtze River. Methods] HJ-A-B satellite image data in 2010 of Xihe catchment, Shangnan County in Danjiang basin were collected and analyzed with Erdas software to get the coverage of different vegetation types. Vegetation factors calculation method that was put forward by Bu Zhaohong, termed as remote sensing monitoring models(QRSM) for soil erosion quantitative was used to get the formula relationship between vegetation factors and vegetation coverage. and to study the vegetation cover factor of Xihe catchment by remote sensing monitoring. Results] The vegetation cover and engineering measures factor value in the harnessed north area and the southern mountain of Xihe catchment are quite low. Higher values of them can be found sparsely distributed in rive sides. It is mainly because of house and road constructions taking over vegetation. A consecutive higher vegetation cover factor was found in the middle of the Xihe catchment, where though the population is concentrited, the measurement factor is lower. Conclusion] There are many natural factors affecting soil and water loss, among which the vegetation cover is the greatest one. Human activities should not be neglected, the over-exploitation and utilization of land resources can also change terrestrial ecosystem. Therefore, study of soil and water loss should take into account the geographical, natural and economic development. According to local condition, reasonable planning should be carried out to ensure sustained and stable economic development and ecological security.