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The results showed that the concentration of four air pollutants in the central and northern cities were significantly higher than that in the southeast coastal cities and southwest cities. The most important factor affecting the concentrations of NO2, SO2, PM2.5 and PM10 was the impervious ratio, with relative contribution rates of 40.7%, 36.3%, 51.0% and 51.8% respectively. The results of sub-region analysis showed that the most important influencing factor differed in different regions, including the impervious ratio in the East and Central China; the number and density of buildings in South China; the impervious ratio and diversity of building types in North China; the impervious ratio and the number of buildings in Northeast China, the density of buildings in Northwest China. Such differences were mainly caused by climate, topography, urban planning, and other factors.Vegetation restoration is an important requirement for ecological protection and high-quality development in the Yellow River Basin. In-depth understanding the temporal and spatial differentiation of vegetation has important practical significance. Colivelin With the four Landsat TM/OLI remote sensing images as the data source, the pixel binary model was used to estimate vegetation coverage. The transfer matrix, geological information map, and the center of gravity migration model were used to analyze the temporal and spatial variations of vegetation coverage in Yan’an City in the middle of the Yellow River Basin from 1988 to 2018. The spatial variation of vegetation cover to elevation and slope was explored using terrain distribution index combined with terrain data. The results showed that vegetation coverage in Yan’an was low in the north region and high in the south region. The vegetation coverage increased significantly due to policy changes. From 1988 to 2018, the vegetation change pattern in Yan’an was dominated by continuous improvement and stability. Vegetation coverage increased in about 50% of the area. 83% of the study area with high vegetation coverage remained stable. At each elevation and slope level, the advantage of high vegetation cove-rage increased with time. At each slope level, vegetation cover increased with slope. The transition direction of vegetation cover of different levels in Yan’an was basically consistent with the overall spatial change trend of vegetation cover, with the overall shift being from north to west. The vegetation construction in Yan’an has achieved remarkable results, though the vegetation coverage in the north still needs to be improved. Optimizing vegetation types and structures is an important direction for future vegetation construction.Based on the theories of geography and landscape ecology, land ecological restoration is an important strategy to promote ecological civilization and build a beautiful China. Land ecological restoration in China has the characteristics of multi-disciplinary theoretical system, diverse work mode, integration of technology and methods, and diversified practice and exploration. The overall effectiveness of the work coexists with arduous tasks. Based on the new challenges in land ecological restoration, we summarized the overall framework and technical path of land ecological restoration, the working mechanism and mode of regional land ecological restoration, the content system and technical standards of land ecological restoration. In the new stage, the top-level design of land ecological restoration in China should focus on the work system, business boundary and institutional system, identify the responsibility boundary of different business processes, and realize the closed management of the whole work chain from the perspective of theory, system, engineering and technology. Rural settlement area, urban built-up area, industrial and mining gathering area, ecological function area and blue ocean area are the five major elements of regional scale land space, which correspond to five different ecological restoration modes, namely, comprehensive land improvement, urban renewal and double repair, mine geological environment restoration, mountain-river-forest-farmland-lake-grassland restoration, and blue bay restoration. It is necessary to comprehensively use the thinking of “Three Integrations” (information, technology, and process) to build a set of regional land ecological restoration work mode covering the integration of investigation, monitoring and evaluation, land space planning, project implementation, project acceptance and ecosystem monitoring and evaluation.Based on the pressure-state-response (PSR) model and entropy method, we analyzed the health status of land ecosystem and the temporal and spatial variations from 2009 to 2017 in ten cities and one district in Shaanxi Province. The driving factors affecting the health of the land ecosystem was examined. Results showed that during 2009-2017, the overall health of the land ecosystem in Shaanxi Province was improved, which was lower during 2009-2014 and being obviously improved after 2014. The health level of land ecosystems in Xi’an, Baoji, Weinan and Hanzhong was high and with substantial variation, while that in Yan’an, Yulin, and Ankang was low and stable, decreasing in order of South Shaanxi, Guanzhong region and North Shaanxi. Overall, the pressure, state and response indices of the land ecosystem in Shaanxi Province increased during 2014-2017 with a gentle growth, which were basically flat after 2014. Those results indicated that the land ecosystem in Shaanxi Province was at a stable and healthy state. Population growth, urbanization level, fertilizer load per unit of arable land, forest coverage rate, industrial wastewater discharge compliance rate and comprehensive utilization rate of industrial solid waste were the main driving factors for the health of land ecosystems in Shaanxi. Controlling the use of fertilizers and pesticides, optimizing the structure of land use and improving land use efficiency are necessary strategies to promote the construction of ecological civilization and implement the red line of ecological protection for Shaanxi Province.