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The change characteristics of eco-environmental quality of Heidaigou mining area and Harwusu mining area from 2000 to 2020 were analyzed, in order to grasp the inducement of eco-environment quality change and provide scientific basis for further ecological management decision-making in mining area. A total of 21 Landsat remote sensing images were selected from 2000 to 2020 (August). The greenness index (NDVI), wetness index (WET), heat index (LST) and dryness index (NDSI) were calculated by removing cloud pixels and masking the water body information. Based on this, principal component analysis (PCA) was used to construct remote sensing ecological index (RSEI), and the eco-environmental quality of the mining area from 2000 to 2020 was evaluated. The results show that from 2000 to 2020, the RSEI of disturbance area and recovery area of the mining area decreases slightly in the early stage and increases as a whole in the later stage. The eco-environmental quality of the mining area experiences a deterioration-recoverystable development trend in the past 21 years, in which the deteriorating area accounted for a relatively large proportion from 2000 to 2010, and from 2010 to 2020, the proportion of deteriorated area decreases, while the proportion of improved area increases. In the center of gravity migration of eco-environmental quality in mining area, the migration trajectory of gravity center of Ⅰ and Ⅱ is basically the same, and the migration range is large, and the migration of gravity center of Ⅲ, Ⅳ and Ⅴ is closely related to the position of dump in mining area. The eco-environmental quality assessment on the mining area scale is not only convenient to obtain data and save calculation time, but also can timely and accurately grasp the ecological environment quality of the mining area, and the evaluation results are more reliable, which is consistent with the actual monitoring results of the mining area. [ABSTRACT FROM AUTHOR]

The urban development of central Yunnan faces various pressures such as insufficient resources and environment per capita, uneven distribution of resources, and fragile ecological environment. The study selected 4 TM images in 1990, 2000, 2010 and 2018 to study the temporal and spatial changes of land use / over, its landscape pattern evolution characteristics and ecological environment effects in the central Yunnan urban agglomeration. The results show that as follows. The fragmentation degree of other land use / over increases gradually, and the shape becomes complex. With the development of the city, except for the construction land landscape type connection degree increases, the rest land use decreases and the fragmentation degree increases. The land-averaged ecosystem service value of the central Yunnan urban agglomeration is generally lower, and the spatial expression is lower in the east and higher in the west, and there are large differences between districts and counties. The overall ecological environment tends to deteriorate, and the factors causing the improvement of the ecological environment are the conversion of forest land, water area and cultivated land convert into construction land. When the slope is less than 3 degrees, the hydrological regulation waste disposal value is larger, and when the slope is greater than 3 degrees, the biodiversity conservation and soil formation and protection values are higher, while the food production and aesthetic landscape values are lower. The regional agglomeration type of forest and water area is high-high clustering, and the regional agglomeration type of construction land is low-low clustering. The ecological environment quality of about 59% of the districts and counties in the central Yunnan urban agglomeration declined, and 32% of the districts increased. The development of the urban agglomeration in central Yunnan should improve the structure and efficiency of land use, and increase environmental protection efforts [ABSTRACT FROM AUTHOR]

The remote sensing data of land use were used to analyze the spatial-temporal pattern evolution of “Production-LivingEcological Space” and the ecological environment effect under the land use transformation of “Production-Living-Ecological Space” in Dongting Lake eco-economic zone from 1990 to 2020 by using the three-generation spatial dynamic attitude, three-generation spatial transfer matrix, ecological environment quality index and ecological contribution rate of three-generation spatial transfer. Finally, the global and local effects of driving factors and their effects were analyzed by geographical detector and geographical weighted regression model. The results show that from 1990 to 2020, the “Production-Living-Ecological Space” of Dongting Lake eco-economic zone has evolved into the characteristics of increasing living and ecological space and decreasing production space. The ecological environment quality of Dongting Lake eco-economic zone shows a U-shaped spatial distribution pattern of high in the east and west and low in the middle and north. The ecological environment quality index of Dongting Lake eco-economic zone rises from 0. 513 983 to 0. 515 311 from 1990 to 2020. The transformation of agricultural production and rural living space into water and forest ecological space is an first cause for the improvement of ecological environment quality. From the global driving effect and local driving effect of space, altitude, slope, population density, distance from water area and ecological protection project are the dominant factors of ecological environment quality pattern, the factor interaction is double factor enhancement, and the spatial difference is obvious. The research results can provide reference for the rational development of land space and the formulation of ecological environmental protection policies in Dongting Lake eco-economic zone. [ABSTRACT FROM AUTHOR]

The ecological environment of Karst areas is relatively fragile, and timely monitoring of the temporal and spatial changes of its ecological environment is of great significance. The typical Karst geomorphic region, Duan County, Hechi City, Guangxi, was selected as the research object, and Landsat-5 / TM and Landsat-8 / OLI in 2000, 2004, 2010, 2014, and 2019 were selected as the main data sources, and humidity, greenness, and dryness were selected. The four ecological factors of heat and heat construct a modified remote sensing ecological distance index (MRSEDI) to monitor the ecological environment quality of Duan County in the past 20 years, and use the GM (1, 1) model to change the MRSEDI Trend forecasts. The results show these as follows. The average value of the correlation coefficient between the MRSEDI index and each ecological factor is above 0.7, and MRSEDI is comprehensively representative in regional ecological environment assessment. From 2000 to 2019, the eco-environmental quality of Duan county showed a trend of “declining first, then increasing, and increasing overall”. The average MRSEDI value rose from 0.5989 to 0. 6362, and the quality of the habitat continued to improve. The MRSEDI index of Duan county in 2024 is predicted by the GM(1, 1) model to be 0.6471, indicating that the ecological environment quality of Duan county will continue to improve. [ABSTRACT FROM AUTHOR]