Ecological sensitivity is one of the most important indicators used to evaluate regional ecological environment. Its research is significant to regional ecological governance and management. Therefore, six indicators including biodiversity, hydrothermal environment, soil salinization, land desertification, soil erosion and human disturbance from the perspectives of natural ecosystems, natural-social ecosystems, and social ecosystems and the entire-array-polygon indicator method were used to calculate terrestrial ecological sensitivity of China from 2000 to 2018. Besides, the spatio-temporal evolution characteristics were also analyzed with the grid coding method. The results showed that: (1) China's terrestrial ecological sensitivity was generally stable from 2000 to 2018, between 0.33-0.34. However, it declined from 0.342 in 2000 to 0.333 in 2018, which indicates that China's terrestrial ecological sensitivity is gradually improving. (2) There is significant spatial heterogeneity of ecological sensitivity in China, showing a spatial distribution pattern of "low in the east and high in the west, and low in the south and high in the north", and "high in urban areas and low in suburban areas". This is mainly due to the poor natural environment in the western and northern regions of China, poor ecological self-regulation ability, and being prone to be affected by external factors. (3) In terms of driving factors, China's terrestrial ecological sensitivity is greatly affected by soil (land) environmental factors. But at the same time, the influence of human disturbance factors is increasing year by year, which shows that China's terrestrial ecological environment management and protection work still has a long way to go.

The rapid urbanization of China's urban agglomerations in recent decades has resulted in over-occupied ecological space and increased ecological pressure, which has become an important factor restricting regional healthy development. This paper examines the structure and distribution characteristics of "production-living-ecological" spaces of five mega-urban agglomerations in China, namely, Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD), Guangdong-Hong Kong-Macao Greater Bay Area (GBA), Chengdu-Chongqing (CY), and the middle reaches of the Yangtze River (MYR), and analyzes the spatial and temporal variation characteristics of ecological space and the influencing factors of its changes in 1990-2020. Then it explores the comprehensive ecological carrying capacity of water resource supply, water quality regulation, air quality regulation, and leisure and recreation space. The results show that: (1) Urban agglomerations at different developmental stages present different area ratios of the "production-living-ecological" spaces, living space expansion patterns dominated by multi-center combination, and structure of ecological space including barrier type, compact, discrete, and full enveloping type. (2) In the study period, the area of living space in urban agglomerations increased significantly while the area of production space decreased. The ecological space of all the urban agglomerations except the GBA increased. In the last 10 years, the increase of ecological space accelerated significantly. The spatial structure of "production-living-ecological" spaces and its characteristics of spatial and temporal evolution indicate that the main functions of production and ecological space in mega-urban agglomerations have shifted from supply to regulation and culture, and reflect the transition from rapid urbanization to new sustainable urbanization in China. (3) The ecologically overloaded cities in the BTH, YRD, GBA, CY, and MYR account for 78.6%, 73.1%, 54.5%, 56.3%, and 25.8% of the respective urban agglomeration. Water supply and water quality regulation are the main factors that restrict the ecological carrying capacity of BTH and YRD, while leisure and recreation services restrict the ecological carrying status of the GBA and CY urban agglomerations. In the future, we need to pay attention to the conservation and rational layout of ecological space to reduce the ecological pressure in urban agglomerations.

Since the implementation of the government initiative-the Development of Western Regions for 2000-2019, a series of major ecological construction projects have been launched, leading to great changes in the ecological conditions and ecological services of western China. This study calculated the amount of total ecosystem services in the western region from 2000 to 2019, and analyzed ecological changes and the characteristics of spatio-temporal variations in ecological services. And a relevant analysis method was applied to explore the trade-offs and synergy of service. It was found that the area of settlements and wetland ecosystems in the study area increased significantly from 2000 to 2015, whereas grassland showed a downward trend year by year. The vegetation fraction showed a decreasing zonal distribution from south to north. A fluctuating increase was observed during 2000-2019, with inter-annual and large spatial differences. The water conservation service had a slight downward trend from 2000 to 2019, and the main decreasing areas were distributed in southeastern Tibet, the western part of the Three Rivers Source Region, and the karst rocky desertification area. The soil conservation service showed an increasing but fluctuating trend, with the greatest increases observed in the Loess Plateau, western Sichuan and Yunnan provinces, northwest Tibet, and southeast Tibet. The windbreak and sand fixation showed a downward trend, and the sharp decline was mainly found in the central and western parts of Inner Mongolia, Tibet and parts of northern Xinjiang. Ecosystem supply, water conservation, and soil conservation were synergistically connected, they were observed north of the Huaihe River-Qinling Mountains, especially in Ningxia and Inner Mongolia. Ecosystem supply was mainly trade-offs with windbreak and sand fixation, and it was observed in the farming-pastoral transitional zone. The synergistic degree of ecosystem services in areas subjected to ecological engineering policy was greater than that in non-engineering areas. Quantitative assessment of ecosystem service changes and their trade-offs is helpful for scientific ecological management and maximizing ecological benefits.

National park cluster is an important mode to explore the coordination of ecological security barrier and regional sustainable development of the Qinghai-Tibet Plateau. Thoroughly studying multi-functional structure plays an important part in promoting the orderly organization and coordinated construction of national park cluster in the Qinghai-Tibet Plateau. Based on the Pressure-State-Response Evaluation Model, Rank-Size Rule and Coupled Coordination Degree Model, this study established a functional structure evaluation system to analyze the multiple functional categories, hierarchical and functional structure characteristics of national park cluster. Results show that: (1) To achieve sustainable development, endogenous relationship and denotative relationship should be addressed for the national park cluster. Internally, it is necessary to promote rational allocation of interests among ecological protection, recreational utilization and community development. Externally, the ecological security barrier function and regional green development should be achieved through the orderly organization of individual parks, and the collaborative evolution relationship should be handled in the scale span process of ecological protection, scientific research, education, recreation and community development. (2) The functions of ecological protection, recreation and community development in the Qinghai-Tibet Plateau National Park Cluster are prominent, and there is great potential for improvement of scientific research and education functions. The Zipf index shows the multi-functional level conforms to the Rank-Size Rule and presents a balanced development. Hence, the individual national parks need to strengthen their dominant functions according to their characteristics. (3) The coupling degree and coordination degree of multi-functions of the Qinghai-Tibet Plateau National Park Cluster are 0.7809 and 0.6227, respectively, showing high-intensity coupling and intermediate coordination state. Because of great differences in the coupling strength and coordination level among individual parks, the functional structure is classified into four types of comprehensive coordination, advantage development, general development and general lag. This study not only enriches the function evaluation and structure research of national park, but also provides scientific references for the functional optimization and sustainable development of the national park cluster on the Qinghai-Tibet Plateau.

Agricultural modernization is important for rural construction, social economy, and civilization development. Based on the statistical data of the Qinghai-Tibet Plateau from 1990 to 2017, we built a comprehensive index system with agricultural modernization as the primary index, agricultural input level, agricultural output level, and sustainable agricultural development level as the secondary indexes, and then obtained the weight of each index through the entropy value method. Finally, the agricultural modernization index and driving factors on the Qinghai-Tibet Plateau were calculated. The results showed that: (1) from 1990 to 2017, the agricultural modernization level in the study area is generally low (with the value of 0.15) compared with the average level of China, showing an increasing trend; (2) the counties of relatively high level of agricultural modernization such as Dege, Huangzhong, Bailang, and Langkazi are scattered in the northern, southeastern and southern edges, and the YLN (Yarlung Zangbo River, Nyangqu River and Lhasa River) region of the Qinghai-Tibet Plateau; (3) electricity consumption per unit cultivated area, effective irrigation rate and land productivity had the greatest effects on the agricultural modernization level on the plateau, with the contribution degrees being 13%, 12% and 11%, respectively.

How to simulate the scenarios of land cover change, driven by climate change and human acitivities, is not only a hot issue in the field of land cover research, but also one of the core topics in the sustainable urbanization. A new method of scenarios of surface modeling in land cover (SSMLC) was developed to simulate the scenarios of land cover driven by the coupling of natural and human factors. Based on the climatic scenario data of CMIP6 SSP1-2.6, SSP2-4.5 and SSP5-8.5 released by IPCC in 2020 that combined the shared socio-economic paths (SSPS) and typical concentration paths (RCPs), the observation climatic data, the human data of population, GDP and transportation, the current data of land cover in 2020, and the related policies, scenarios of land cover in Beijing-Tianjin-Hebei (BTH) region are simulated under scenarios of SSP1-2.6, SSP2-4.5 and SSP5-8.5 during the periods of 2040, 2070 and 2100, respectively. The simulation results show that the overall accuracy of SSMLC in the BTH region is up to 93.52%. During the period from 2020 to 2100, change intensity of land cover in the BTH region is the highest (an increase of 3.29% per decade) between 2020 and 2040, and it would gradually decrease after 2040. Built-up land would have the highest increasing rate (an increase of 4.741% per decade), and the wetland would have the highest decreasing rate (a decrease of 2.64% per decade) between 2020 and 2100. The change intensity of land cover under the scenario SSP5-8.5 is higher than that under the scenarios of SSP1-2.6 and SSP1-2.6 between 2020 and 2100. The impacts of GDP, population, transportation and policies on the changes in cultivated land, built-up land, wetland and water body are generally higher than on other types of land cover. Moreover, the research results indicate that the SSMLC method could be used to explicitly project the changing trend and intensity of land cover under different sceaniros, which will benefit the spatial optimal allocation and planing of land cover, and could be used to obtain the key data for carrying out the eco-environment conservation measures in the BTH region in the future.

Lung cancer is one of the most common malignant tumors and the main cause of death related with cancer. The incidence rate and mortality rate of lung cancer in Henan are the highest of the cancers. Therefore, it is of great significance to study the spatial distribution pattern of lung cancer and the effects of environmental factors on it for the prevention and control of lung cancer. Based on the data of lung cancer incidence in Henan from 2016 to 2018, the spatial distribution pattern of lung cancer in the province was studied by using spatial autocorrelation analysis. Using the software Geodetector, we quantified the explanatory power of each factor and its interactions on lung cancer incidence rate. The results showed that lung cancer has obvious characteristics of agglomeration, the high incidence areas are concentrated in the plains and basins of central, eastern and southern Henan. Among the 12 environmental factors selected, PM_2.5 concentration, O₃ concentration, annual average wind speed, proportion of employees in mining industry and per capita GDP have decisive power, while the per capita GDP and proportion of medical staff have a non-linear enhancement effect on the determination of various factors. The results can provide technical support for research on pathogenesis, prevention and treatment of lung cancer in Henan.