【作者】 洪桢华；

【导师】 刘健； 周小华；

【作者基本信息】 福建农林大学 ， 森林经理学， 2007， 硕士

【摘要】 水土流失是全球性的生态环境问题之一，会导致土地退化、河道淤积等灾害性问题，对人类的生存和发展构成了威胁。传统水土流失监测需要大量的野外调查，耗时多，无法满足流域水土流失的实时监测要求。3S技术的应用，可为实现时空跨度上区域水土流失研究提供详实、快捷、高可信度、直观的动态信息，为区域生态的建设提供有力的科学保障。本研究在3S技术的支持下，利用1986、2003两期闽江流域TM影像，结合现有的水土流失研究基础对闽江流域水土流失状况进行动态监测分析，通过对流域水体悬浮泥沙的遥感分析及流域土壤侵蚀的估测，综合反映该区域的水土流失状况及动态变化，研究主要结论如下：(1)本研究以TM影像为基础数据源，采用图像处理法与悬浮泥沙光谱特性相结合的方法定性提取闽江流域悬浮泥沙分布信息，为水土流失与悬浮泥沙关系研究提供基础数据。(2)根据闽江流域的实际情况，分析影响土壤侵蚀因子，对R、LS等因子进行基于GIS和RS的算法研究，确定因子图。通过植被盖度反演模型的建立确定C因子，最终建立了土壤侵蚀定量估测模型，为流域实施及时的水土流失监测提供了技术支持。(3)本研究通过对闽江流域水体悬浮泥沙的研究，结果表明，闽江流域的水质有下降的趋势，经过18a的演变，闽江水域水体正从清洁水体和低悬沙水体为主逐渐转变为中悬浮泥沙和低悬沙为主。(4)本研究从土壤侵蚀角度分析流域土壤侵蚀空间变化和强度变化，研究表明，闽江流域水土流失面积和水土流失率呈下降趋势；从侵蚀模数变化分析可知闽江流域水土流失的强度有增加的趋势，流失量在加大，目前闽江流域轻度以上的土壤侵蚀以中度侵蚀为主。(5)闽江流域的悬浮泥沙等级分布和流域土壤侵蚀强度具有较强的一致性：流域水土流失面积虽然减少，但是整体流失强度有增加的趋势，致使流域的水土流失量有所增加，对此相应河段的悬浮泥沙浓度总体上也在提高。更多还原

【Abstract】 Water and soil losses is one of ecological environment problems in the earth, It causes the disasters of the descent of soil quality and silting of river. It has resulted in the threat to humanity’s survival and the development. The traditional water and soil losses monitor needs the massive field investigation, consumes much time and is unable to satisfy the real-time monitor request of river basin soil erosion. The application of Geomatics supllys full accurate, rapid ,high credibility, audio visual dynamic information for space-time span regional soil erosion reseach and provides the powerful scientific assurance for regional ecological construction. This research based on Geomatics , employed 1986 and 2003 year TM remote sensing image and used the existing water and soil losses research in Minjiang watershed, carried out the dynamic monitor analysis to the Minjiang watershed’s soil erosion condition, through remote sensing analysis of suspend sediment and estimation of watershed soil erosion model reflected the water and soil losses condition and its dynamic change in Minjiang Watershed.this region, the main conclusion are as follows :(1) This research takes the TM image as the foundation data resouse, uses the image process method and combine with the suspend sediment’s spectrum characters, withdraws the Minjiang watershed’s suspend sediment distribution information, provides the foundation data for relations research of water and soil losses and suspend sediment.(2) According to the Minjiang watershed’s actual situation ,carrys out the algorithm research of the elements of R ,LS based on GIS and the RS to determine the factor chart, through the establishment of the vegetation coverage inverse model determined the C factor, has established the soil erosion qualitative estimation model and has provided the technical support for promptly implementing water and soil losses monitor of watershed.(3) This research through the research on Minjiang watershed’s suspend sediment, finally indicates that: the Minjiang watershed’s water quality is t on the decline, and passes through the 18a’s evolution, the Minjiang’ s water body is gradually transforming from clean water and lowly hanged sand to the middle and low suspend sediment primarily. (4) this research from the soil erosion analysize spatial variation and the intensity variation of soil erosion , the research indicates that the Minjiang watershed soil erosion area and soil erosion rate assume a drop tendency; from the corroded modulus change analysis we can see that Minjiang watershed soil erosion’s intensity is on the increase trend, water and soil losses quantity is enlarging ,at present Minjiang watershed mildle soil erosion is primarily(5) the Minjiang watershed suspend sediment distribution and the soil erosion intensity has a stronger uniformity: although the watershed water and soil losses area reduces, the whole drains intensity is on the increase trend, which causes the soil erosion quantity increase, and the corresponding section of river suspend sediment density is increasing .更多还原