Characteristics Of Soil Erosion And Planning Of Water And Soil Conversation During The Construction Of Thermal Power Plant

In China, there are many types of development and construction projects of under-construction, and the surface disturbance forms are complicated in construction area. So it is very necessary to analyze soil erosion characteristics of different development and construction projects and study soil erosion problems of that. The soil erosion induced by thermal power plant project construction has became a typical problem in the study of soil erosion caused by punctate development and construction projects in the past few years. Taking the Jingmen power plant,Xiangfan power plant and Ezhou power plant as the cases study, this paper analyses soil erosion characteristics and soil and water conservation measures of thermal power plant project construction by means of observation on the situation of soil erosion . The results are as follow:1. According to the basic characteristics of the study area assessment results, some regions were divided in the thermal power plant project area, which were major factory district, cycle pipeline and drainage facilities area, spoil area, construction area, special railway line etc. During the whole construction period,erosion amount of major factory district, construction area,cycle pipeline area and temporary spoil areawas relatively high at the prophase of construction process,and was low at the later stage; erosion amount of permanent spoil area increased gradually; erosion amount of special railway line increased gradually and reached stable after the construction was completed. From the perspective of disturbance time,the distribution to disturbance time of major factory district and construction area were in early-middle construction period and erosion peak was present to the prophase of construction process; the disturbance time of spoil area, special railway line , cycle pipeline area were throughout the whole construction period. the erosion peak of provisional spoil area,special railway line,cycle pipeline area appeared on the earlier-stage and that of permanent spoil area,special railway line appeared at the later stage.From the view of the total amount of erosion(Q) in each subarea, railway line>cycle pipeline>major factory district>construction area>spoil area in Xiangfan power plant and Jingmen power plant, cycle pipeline>spoil area>construction area > major factory district in Ezhou power plant. On the point of erosion rate(R) , cycle pipeline > railway line > spoil area >major factory district> construction area in Xiangfan power plant and Jingmen power plant, cycle pipeline >spoil area>construction area>major factory district in Ezhou power plant. The results of analysis showed: erosion rate of cycle pipeline was greater than 2500 t/km2.a, which belonged to middle degree erosion; erosion rates of railway line and spoil area were greater than 1000 t/km~2.a, which belonged to light erosion; in other region erosion amount were less, which belonged to slight erosion.The soil mass was disturbed dramatically at special railway line, cycle pipeline and spoil area in each power plant, and total erosion proportions of three regions of Jingmen power plant,Xiangfan power plant and Ezhou power plant were 73.9%,70.13%,81.64%, respectively,which were the key regions of soil and water conservation.2. The suitable research methods were selected according to erosion characteristics of in the thermal power plant projects. In the major factory district and construction area, located monitoring was difficult to implement because of the relatively small erosion amount and erosion rate,the large artificial disturbance, centralized erosion process and the short erosion duration time, so we mainly adopted field survey and patrol to obtain basic data and calculated the amount of soil erosion using a model to predict the soil loss amount. In the spoil area, cycle pipeline and special railway line area, there were drastic disturbance,high erosion rate and a long erosion duration time, so the simple observation areas offixed pile method were set up; the average fall of observation surface of each observation area was observed periodically and the soil loss amount was calculated using formula.3.In the thermal power plant projects soil and water conservation measures included three types : temporary measures, engineering measures and vegetation measures. Temporary measures included polythene mulch and temporary retaining wall; engineering measures included drainage facilities, permanent hardening, retaining wall, drainage engineering, mortar flagstone revetment, bridge and culvert protection engineering; vegetation measures included sod mulch, planting tree and planting crops. To effectively reduce soil erosion. conservation measures should be arranged reasonably according to soil erosioncharacteristics of each study area in the thermal power plant projects.