Ecological Environment Evaluation Of Mining Area Based On Remote Sensing Ecological Index

Ocated at the top of the ecological barrier in China's southwest border and the plateau in East Asia,the uplift of the Qinghai Tibet Plateau has not only formed a unique geological structure and won the title of "the third pole of the earth",but also Tibet contains many mineral resources,which is the country's successor strategic base for the extraction and production of important resources in the future.In recent years,the development of mineral resources in Tibet has made outstanding and positive contributions to the total amount and growth rate of the regional national economy,alleviating the pressure of the bottleneck of national resources and driving the correlation effect of other industries.The Qinghai Tibet Plateau is the largest "source of rivers" in Asia and even the world.The regional climate is complex and diverse.Some areas are cold and dry all year round,and the ecological environment is extremely fragile.The special geographical location and unique landform have led to slight changes in the ecological environment of Tibet,which is enough to pose a serious threat to the ecological security of surrounding countries and regions.Therefore,integrating the concept of harmonious development of ecological environment into the whole life cycle of mine exploration,feasibility study,construction,operation and closure has become a key problem to be solved in the plateau mining development in Tibet.Taking Jiama Copper Polymetallic Mine in Tibet as the research object,based on the remote sensing satellite Landsat TM/ oli data,with the help of geographic information technology and relevant statistical analysis methods,this paper collects and processes the remote sensing satellite images of Jiama mining area in Tibet from 2009 to 2020,and inverses the ecological indicators that can reflect the vegetation cover,humidity,dryness,surface temperature and so on,According to the index selection and processing method of remote sensing ecological index rsei,the principal component analysis model is used to evaluate,analyze and dynamically monitor the ecological environment quality of Jiama mining area in the past ten years.At the same time,this paper studies the spatial distribution and trend characteristics of the ecological environment in Jiama mining area from the time and spatial scale,compares and analyzes the ecological environment evaluation results of Jiama mining area in combination with natural,cultural and policy factors,and explores the main causes of environmental changes in Jiama mining area,so as to provide scientific and objective data support for the ecological environment improvement of departments and enterprises.(1)Over the past 12 years,the eco-environmental quality of Jiama copper polymetallic mining area in Tibet has shown a trend of first decline and then rise.The rsei indexes in 2009,2014 and 2020 were 0.5654,0.5131 and 0.5378 respectively.The index includes four indexes,namely greenness,humidity,dryness and heat.The research results show that these four indexes have a great impact on Jiama mining area,especially heat and greenness,followed by humidity and the smallest dryness.Generally speaking,the ecological environment quality of Jiama mining area has developed in a good direction in the past 12 years.(2)The grade classification evaluation shows that the ecological quality grade area of Jiama mining area was dominated by "good" in 2009,the ecological environment quality grade area of Jiama mining area was dominated by "poor" in 2014,and the ecological environment quality grade area of Jiama mining area was dominated by "medium" in 2020.The ecological environment quality of Jiama mining area tends to be "medium" as a whole.Taking 2020 as an example,the ecological grade in Jiama mining area is medium,accounting for the largest area,36.59%,followed by the poor,accounting for 31.62%,followed by the excellent grade,accounting for 25.72%,and the poor grade,accounting for the least area,6.07%.(3)From the dynamic analysis of time series,during 2009-2014,the proportion of regional area with relatively stable changes in the ecology of Jiama mining area was55.36%.During this period,the ecological quality and environment of most regions of Jiama mining area remained relatively stable.The proportion of regional change area with ecological degradation is 43.43%,dominated by slight degradation.During this period,the ecological improvement area of the mining area accounts for 1.21% of the ecological change area of the whole region.It shows that the eco-environmental quality of Jiama mining area has deteriorated from 2009 to 2014.From 2014 to 2020,the area with relatively stable ecological quality in Jiama mining area accounts for about 15.58%of the area with changes in ecological quality in the mining area;During this period,the total area where the ecological quality has improved accounts for 58.76% of the area where the ecological quality has changed,in which the change of ecological grade is dominated by moderate improvement,followed by slight improvement.During this period,the ecological degradation area of Jiama mining area is dominated by slight degradation,followed by moderate degradation,accounting for about 20.50% of the change area of ecological and environmental quality.From 2014 to 2020,the ecological environment quality of Jiama mining area has improved.(4)From 2009 to 2020,the attention paid by the Tibet Autonomous Region Commission,the government and huatailong mining group to ecological and environmental protection and the investment of a large amount of funds are important reasons for the gradual restoration and improvement of the ecological and environmental quality rsei in Jiama mining area.