Inversion And Risk Assessment System Of Heavy Metals In Soil Of Solid Waste Storage Yard In Large Coal Power Base

Large scale coal mining has promoted the rapid development of China’s industrial economy.However,a large number of coal based solid wastes,such as fly ash and coal gangue,generated in the production process,not only occupy land resources,but also bring pollution risks to the soil ecological environment around the coal mining area.Waste generated by coal mining constantly migrates and releases heavy metals to the surrounding environment,leading to sustainable environmental ecological risks,The long-term release process will pose a great threat to the surrounding environment and residents’ health.However,the environmental and ecological risk management and control for the overall stockpiling of large quantities of coal based solid wastes in large areas lacks the most basic continuous and rapid monitoring,analysis and diagnosis means.Therefore,it is necessary to develop a system that can achieve the assessment and control of soil pollution from the acquisition of pollution data,and use modern spatial information technology to assist decision-makers in controlling heavy metal pollution in large coal related industrial clusters and surrounding soils.According to the research on hyperspectral retrieval of heavy metals in soil and environmental pollution risk assessment at home and abroad,the demand analysis and overall design of the system are carried out.On this basis,with Microsoft Visual Studio 2016 as the development platform,C # language,Arc GIS Engine 10.2 as the main development component,and GIS secondary development technology,the hyperspectral remote sensing quantitative inversion model and soil environment mathematical model were compiled,and the soil heavy metal inversion and risk assessment system for large coal power base solid waste storage yard was developed.Finally,taking the No.1 storage yard of fly ash in Tunlan mining area,Gujiao City,Shanxi Province,as an example,the application of the system is verified.The main work and research results are as follows:(1)According to the demand for heavy metal monitoring and risk management and control in the soil of large coal power base storage yard,the demand analysis is carried out in three aspects: business,function and performance.The overall system design including system design principles,system design objectives,system interface design,system structure design and system function design is completed.(2)According to the different data types in practical applications,a joint database associated with Geodatabase and SQL Server is designed and established to store the data in the system.The association between databases is realized by using Arc SDE,a spatial database engine,to achieve efficient management of spatial data and attribute data.(3)The basic map use function,data query function,soil heavy metal retrieval function and soil heavy metal risk assessment function including a variety of soil pollution assessment models are developed and implemented.(4)Taking No.1 coal ash yard in Tunlan mining area as an example,the system is applied.Based on the measured values of soil heavy metals and hyperspectral remote sensing data in the study area,the model parameters were set,and the hyperspectral retrieval model of soil heavy metals was constructed.The soil pollution in the study area was comprehensively analyzed by using single pollution factor,weighted average index method,Nemero index method and Hakanson potential ecological hazard index method.The results showed that the heavy metal pollution in the soil was mainly located inside the fly ash yard,and the pollution in the north of the yard was more serious.