Research On Erosion Investigation,evaluation And Control Strategies Of Raclaimed Soil In Mining Area

Soil erosion is one of the main ecological and environmental problems faced by reclaimed soil in mining areas,which brings great obstacles to the management of the environment and seriously affects the effect of ecological restoration.Regular monitoring and evaluation are effective means to understand the soil erosion status,so that soil erosion problems can be detected in time and prevention measures can be taken to prevent the continuous deterioration,however,traditional remote sensing monitoring cannot achieve regular monitoring of soil erosion on a small scale.In response,this thesis takes the ecological restoration area of Xilinhot Xiritala Gacha as the research object,and obtains the orthophoto of the research area through the UAV technology.Moreover,through mathematical modelling and theoretical analysis,the method of soil erosion gully identification,depth of erosion gully and erosion volume measurement is proposed,and a model for evaluating the development degree of gully erosion on the slope is constructed.The thesis also uses the RUSLE model to evaluate the intensity of soil erosion,analyses the relationship between gully erosion and sheet erosion and the development characteristics of soil erosion,and proposes corresponding soil erosion control strategies on this basis.The main results and conclusions are as follows:(1)A soil erosion survey and monitoring method based on UAV remote sensing is proposed,which mainly includes soil erosion gully identification and extraction,erosion gully depth measurement and erosion volume measurement: using UAV images,an object-oriented classification method is adopted to identify and extract soil erosion gullies on the basis of determining the optimal segmentation scale for image segmentation;an erosion gully depth measurement model is constructed based on solar altitude angle and solar azimuth angle.A model was constructed to measure the depth of erosion gullies based on solar altitude angle and solar azimuth angle,and it was verified that the maximum error was 1.8 cm and the minimum error was 0.5 cm;by building the original DEM before erosion,a model was constructed to measure the amount of soil erosion,and the feasibility of the method was verified.The erosion gully identification results and accuracy of different UAV data collection heights were compared,providing a basis for the selection of UAV data collection heights.(2)A method for evaluating the degree of slope gully erosion development was proposed,and the grading criteria for the degree of erosion gully development were determined to evaluate the degree of slope gully erosion development.The main factors affecting soil erosion were measured using the research data,and the intensity of soil erosion was evaluated based on the RUSLE model.The results showed that,overall,gully erosion is serious in the study area,while sheet erosion is not a serious problem.(3)Reveals the interrelationship between the development degree of gully erosion and the intensity of sheet erosion on the slope,which is influenced by rainfall,topography,soil and vegetation.The study shows that as the intensity of sheet erosion increases,the degree of gully development on the slope also gradually becomes higher,but the higher the soil erosion intensity has less influence on the degree of gully development,and the development of gullies in turn affects the intensity of sheet erosion.Under the combined influence of multiple factors,the development of sheet erosion in the study area is more concentrated in the moderately sensitive area,and there is a threshold value for the influence of vegetation cover and slope on the development of erosion gullies,which shows an inhibitory effect on the development of erosion gullies when it is greater than this threshold value.(4)It proposes strategies and policy recommendations for the prevention of soil erosion by reclamation,i.e.to design reclamation according to local conditions,improve the investigation,evaluation and monitoring system,implement the prevention and control strategy of integrated and systematic remediation of gully erosion and sheet erosion,development of standards for soil erosion management,and establish a soil erosion monitoring system and a long-term control mechanism.There are 41 figures,25 tables and 115 references in this thesis.