Quantitative Analysis Of The Ecological Environmental Quality And Driving Factors Of The "Three Mountains" In Ningxia Based On Remote Sensing Information

The Helan Mountains,Luoshan Mountains and Liupan Mountains National Nature Reserve are important ecological function areas that play a pivotal role in the construction of Ningxia’s ecological security pattern.The ecological environment of the "three mountains" in Ningxia affects the construction and development of the region,and timely and accurate information on the evolution trend and spatial and temporal pattern of the ecological environment quality of the "three mountains" in Ningxia,as well as analysis of the factors affecting the ecological environment quality,are essential for regional ecological environmental protection,ecological crisis prevention and ecological planning and management.It is important for regional ecological environmental protection,ecological crisis prevention and ecological planning management.In this study,the spatial and temporal evolution patterns of ecological environment quality in the"three mountains" of Ningxia during 1990-2020 were analyzed based on Landsat satellite imagery data and the remote sensing ecological index model(E-RSEI).The spatial and temporal distributions of ERSEI were quantified by using a geographic probe model to reveal the spatial variation of different factors on the ecological and environmental quality of the "three mountains" in Ningxia.The following conclusions were obtained:(1)A new method of assessing ecological environmental quality using four indicators,namely,greenness,humidity,dryness and heat,is proposed to construct an E-RSEI model based on the entropy value method.Compared with the original RSEI model,although the spatial distribution pattern of the two tends to be the same,the improved E-RSEI model can reflect the spatial distribution of ecological environment quality more realistically on a small scale.(2)The trends of greenness and humidity are basically consistent with the E-RSEI.The higher the greenness and humidity are,the higher the surface vegetation cover,the more adequate the soil moisture,and the better the ecological environment quality.The dryness and hotness are opposite to the trend of ERSEI,the more serious the problems such as soil sanding and rock exposure,and the worse the ecological environment quality.(3)Between 1990 and 2020,the average value of the ecological environmental quality of Ningxia’s"three mountains" shows an increasing trend,and the ecological environmental quality is ranked as Liupan Mountain>Helan Mountain>Luoshan Mountain.However,the junction between the protected and unprotected areas and the middle part of Helan Mountain,the high-altitude area in Daluo Mountain and Liupan Mountain National Forest Park show a degradation trend.(4)The future trend of the ecological quality of Ningxia’s "three mountains" will mainly be continuous improvement,but there is still a potential risk of degradation in the ecotourism emergence area in the middle part of Helan Mountain,the high altitude area of Luoshan Mountain,the national forest park of Liupan Mountain and the Qiuqianjia area.(5)The degree of influence of natural and anthropogenic factors on the spatial differentiation pattern of ecological environmental quality is revealed.Climate and elevation are important factors affecting the spatial distribution of eco-environmental quality in the "three Mountains" of Ningxia.With increasing precipitation and elevation and decreasing temperature,GDP and population,the ecological environment quality of Ningxia’s "three mountains" shows an increasing trend.(6)Compared with the single factor,the interaction of driving factors has a stronger explanatory power on the ecological environmental quality of Ningxia’s "three mountains".The single factor explanatory power of human activities on "three mountain" in Ningxia is lower,but the explanatory power of its interaction with environmental factors is significantly stronger,indicating that human activities have significant differences in the degree of influence on regional eco-environmental quality under different environmental conditions.In summary,the E-RSEI model can be used to obtain timely and accurate spatial and temporal patterns and evolutionary trends of the ecological environment quality in the "three mountains" of Ningxia,and from 1990 to 2020,the areas with poor ecological environment quality in the "three mountains" of Ningxia gradually decreased,and the ecological environment quality as a whole improved.The overall quality of the ecological environment is improving,and the trend is increasing in the near future.Climate and elevation factors are important factors affecting the spatial differentiation of eco-environmental quality in the "Three Mountains" in Ningxia.