Study On Inversion Of Heavy Metal Content In Soil And Remote Sensing Monitoring And Evaluation Of Mine Environment

Mineral resources,as one of the necessary elements for human existence and development,have resulted in huge impact on human society and economic construction.However,more and more environmental problems of the mining area and surrounding were gradually emerged due to the exploitation of mineral resources.The heavy metal pollution of soil,accompany with the development of modern mining industry,is gradually invading into our daily life and also harmful to our health.The monitoring and assessment of heavy metal pollution in mine soil and the quality of mine environment can make the supervision department come to know directly the soil contamination degree and the environmental damage caused by mine exploitation,provide the government and regulatory authorities with the support that the introduction of policies about the mine protection,and also contribute to the sustainable development of the mining industry and ecological harmony.The traditional methods of monitoring for heavy metal and mine environment are time-consuming and laborious.Because of its characteristics of high speed and high efficiency Remote sensing technology has become an important tool for environmental monitoring in the new era.Yunnan typical mine base in Gejiu mine and Lanping Jinding mine area,as this research focused on,is a typical example.The relationship between the heavy metal content in soil samples and the spectrum of soil was analyzed by means of field soil sample collection,spectrum and heavy metal determination.The inversion model of soil heavy metal content was established by using three methods,and put forward the band transform method,dependent on multiplicative,to enhance the correlation between heavy metals and spectral sensitive bands,and then drawing the pollution map based on the established optimal prediction model and the ASTER images.Based on a variety of remote sensing image data,remote sensing monitoring of the mine environment and the analytic hierarchy process to select the mine environmental quality evaluation index,then form Gejiu mine environmental quality evaluation in the mean time.Research shows:1.Heavy metal in excess of the standards is in every sampling sites of the study area,and there is a positive correlation among heavy metals.The content of heavy metals is related to the spectral variables(the original spectral reflectance,the first order differential transform and the continuous transformation).The accuracy of the model can be improved by the first order differential transform.2.The maximum correlation band of Zn element is the B515 band,near the absorption peak of zinc containing mineral such as Sphalerite,Zincite,Smithsonite,is an important band for retrieving zinc in soil.The spectral product transform highlight the sensitive bands of the Zn element,while retaining the sensitive information of the original soil band to the most extent.3.The stepwise regression model associated with the soil heavy metal content and spectral variables,the partial least squares model about the soil ASTER measured spectral resampling and the spectra,and the partial least squares model,based on the product transform,dependent on soil sensitive spectral all have been achieved good accuracy,The partial least squares model based on product transform acquired the highest accuracy and the best inversion effect.Obviously,through the transformation of the original spectral band,the estimation precision of model for heavy metals can be improved by choosing a method that can improve the correlation of heavy metal content and soil reflectance spectra,better combinations,and better modeling methods.It provides the basis and reference for the large-scale,rapid monitoring of soil heavy metal content or using remote sensing technology to extract the other pollution information.4.ASTER inversion results show that the mining area as the center,the content of heavy metals,decreasing to the surrounding area.5.There are different degrees of vegetation menace,soil pollution,water pollution and geological disASTERs in the study area.The Gejiu mine environmental benign region accounted for 80%of the total area.The Gejiu mine environment commonly area accounting for 13%of the total area,mainly distributed in the Gejiu northeast regional mining area surrounding.The mine environment is poor area accounting for 7%of the total area,mainly distributed in the southeast region of Gejiu,concentrated in the exploitation of mining intensive area.