Study On Method And Analysis Of Soil Erosion Monitoring During The Period Of Expressway Construction

Water erosion monitoring is the eye of water and soil conservation. It is the prerequisite and base of preventing and controlling soil erosion too. At present, soil erosion monitoring methods have been researched by many people, but their range is mostly confined to a large area of farmland and forest land. The reports on application study of the construction project are few. On the other hand, soil erosion caused by the large-scale construction project (including expressway) is becoming more and more seriously, the proportion is larger and larger. This phenomenon has already aroused wide attention. Based on the Hankou-Shiyan expressway construction project and the conditions of the expressway engineering, we monitors and analyzes the soil erosion during the period of construction. The whole study is divided into two parts.The first part mainly studies the methods and means of soil erosion monitoring during the period of expressway construction. It discusses how to select the soil erosion monitoring points and how to confirm the monitoring methods, the monitoring period and the monitoring frequency. After considering 8 factors of selecting site, such as the representativeness of topography and ground form of monitoring points, we fix 6 soil erosion monitoring points on the connecting section of the Xiang Shi-Xing Jing expressway and the Wudang Mountain-Xujiapong section of the Hankou-Shiyan expressway, set up the experimental spots on them and monitor soil erosion by runoff spots. In terms of being favorable to soil and water conservation, we confirm the rainfall,vegetation cover degree ,thickness of litter and the amount of soil erosion as monitoring projects. As the rainy season in district is from June to September, we confirm that the monitoring period is from April 2003 to November 2004, monitoring frequency is once a month in 2003. And we monitor them in the last ten days of every month.In the second part, according to mathematical statistic principle, the paper mainly deals with and analyzes monitoring data by SPSS (Statistical Package for the Social Science) software, sets up the regression equations, examines goodness-of-fit (R examination), inspects signficance of regression equations (F examination) and analyzes believing degree. We find out: the relation betweenthe amount of soil erosion and rainfall is linear positive relevant relations,and the relations between the amount of soil erosion and the vegetation cover degree and thickness of litter are the obvious negative exponential functional relation.The amount of soil erosion is in close relation with the rainfall. Comparatively, the vegetation cover degree and thickness of litter has a little effect on it. There is a fine soil and water conservation benefit in the measure of plant protection on expressway slope, the amount of soil erosion can be reduced by 90%. There is a different soil and water conservation result in different vegetation measures. Finally, according to monitoring and analysis result, the paper puts forward some corresponding countermeasurses.