| The ecological environment is the basis of human survival.Ecological problems such as resource exhaustion and environmental pollution caused by rapid economic development(such as industrial waste gas,domestic waste water and solid waste discharge,large energy consumption,water shortage,etc.)have a great negative impact on human survival.How to accurately assess the change trend of ecological environment and analyze the factors affecting the quality of ecological environment is the key to achieve sustainable development,and is also a hot issue in current research.Based on this,this study used remote sensing technology,long time series MODIS image data set and Arc GIS10.2 as data processing software to analyze the change trends of green degree(NDVI),humidity(WET),dryness(NDBSI)and heat(LST)in Shaanxi Province from 2000 to 2020.The remote sensing ecological index(RSEI)was established to evaluate the change of ecological environment quality in Shaanxi Province in the past 21 years.On this basis,through the use of multi-level linear model(HLM),ecological,economic and population indicators of Shaanxi Province were selected as driving factors to identify the factors affecting the change of ecological environment quality in Shaanxi Province.The main results are as follows:(1)The quality of the ecological environment in Shaanxi Province has been significantly improved,and the ecological environment restoration has achieved remarkable results.From2000 to 2020,the area of remote sensing ecological index(RSEI)in 0.4-1 of Shaanxi Province increased year by year,from 64.31%in 2000 to 89.1%in 2020.The area between 0 and 0.4decreased year by year,from 22.70%in 2000 to 10.89%in 2020.Based on the analysis of remote sensing ecological index(RSEI)changes over time in Shaanxi Province,the area of ecological environment quality improved from 2000 to 2020 was 1592481.66 km~2,accounting for 77.38%.The degraded area is only 49711.94 km~2,accounting for 2.42%.In addition,the number of counties with"medium"level or above increased from 77 in 2000 to 99 in 2020,an increase of 28.57%,and the most obvious improvement was in the central and northern parts of Shaanxi Province.(2)The influencing factors of eco-environmental quality in Shaanxi Province have multi-level nested relationship and are different with time.In 2000,altitude,slope,precipitation,temperature,carbon emission and PM2.5 were the key factors affecting RSEI;In 2005,altitude,slope,temperature,primary industry,per capita GDP,population density,carbon emission and lighting data were significantly correlated with RSEI;In 2010,precipitation,primary industry,tertiary industry,population density and lighting data were the key factors affecting RSEI.In2015,precipitation,secondary industry,per capita GDP,carbon emission and RSEI were significantly correlated;Slope,tertiary industry,carbon emission and lighting data are key factors influencing RSEI in 2020.Overall,precipitation,temperature,industrial development and carbon emission are the key factors affecting the ecological environment quality of Shaanxi Province,among which carbon emission is always an important factor affecting the change of RSEI in Shaanxi Province,and the factors affecting the change of RSEI gradually change from micro factors to macro factors.(3)In order to coordinate the ecological environmental protection and the rapid development of social economy in Shaanxi province,we should focus on the following aspects:First,strengthen the ecological environmental protection in the northern counties of Shaanxi Province.The results of this study show that the ecological environment quality in the northern counties of Shaanxi Province is poor,and the vegetation coverage rate and the stability of the ecosystem can be improved by implementing ecological restoration,afforestation and other projects.Meanwhile,the control of pollution sources should be strengthened to curb the spread of pollution.The second is to increase investment in greening and humidification.The results of this study showed that greenness and humidity had positive effects on ecological environment quality.It can increase the investment in vegetation coverage and water resources in Shaanxi Province,which can not only directly restore the ecological environment,but also transform the problems of precipitation and temperature rise caused by climate change into favorable factors to improve the regional ecological environment quality,so as to improve the level of greenness and humidity.The third is to make it less attractive to people and industries in dry and hot regions.The results of this study show that dryness and heat have negative inhibitory effects on eco-environmental quality,and population density and industrial development are significant factors affecting eco-environmental quality.The government should strengthen the guidance of industrial development in hot and dry areas and encourage industrial decentralization,transformation and upgrading,so as to reduce the attraction of hot and dry areas. |
