This paper studies the spatial and temporal evolution of regional economic differences and the stage of economic development in the Yangtze River Economic Belt from 1994 to 2017 based on ESDA spatial statistics, variation coefficient and gini coefficient. The spatial heterogeneity of factors affecting economic development differences are analyzed by ordinary least squares (OLS) and geographical weighted regression model (GWR). The results show that: (1) The economic difference of Yangtze River Economic Belt changes from strong agglomeration to weak agglomeration. It has gone through four stages of economic development: germination, rise, prosperity and transformation. It presents the stage characteristics of self-construction and development, regional development, convergence and competition, and industrial transformation. Regional economy presents the situation of “equilibrium unbalance- gradual equilibrium”. (2) The Yangtze River Delta urban agglomeration is the core hot spot area, while Chengdu-Chongqing urban agglomeration and central Yunnan urban agglomeration are the core and sub-core cold spot areas. Economic development experiences alternation of agglomeration effect and trickle-down effect. Regional economic disparities expand first, then decrease, and tend to be balanced, which conforms to the law of “unbalanced growth theory”. (3) Geographically weighted results show that population agglomeration, industrial structure, foreign investment, government regulation and control, traffic development, science and technology education, financial situation are the positive internal driving forces of the spatial and temporal evolution of regional economic development. Development costs and terrain conditions are constraints. Industrial structure is the core driving force. Science and technology education is an important driving force. Terrain condition is the basis of development. When formulating regional development policies, we should consider the heterogeneity and particularity of different administrative regions and driving factors.

The purpose of this study is to reveal the spatial pattern and formation mechanism of urban land prices in Yangtze River Economic Belt. Trend analysis and spatial autocorrelation analysis were applied to reveal the spatial differentiation and correlation characteristic. Furthermore, the driving factors of urban land price in the whole area and its sub-markets were discovered by using geographical detector. The main results as following: (1) The number of cities and urban population showed a fusiform-ranked distribution in Yangtze Economic Belt based on the classification of land price; (2) There was a disparity among cities of different administrative scales, the higher the administrative scale, the higher the land price; (3) From an overall perspective, the urban land prices showed high in the eastern area and low in the central and western area. The distribution of urban land prices showed an “inverted U-shaped” structure from north to south. In other words, the higher urban land prices were closer to the Yangtze River. From a regional point of view, there are abundant features of agglomeration and heterogeneity, such as H-H cluster in Yangtze River Delta Agglomeration and H-L cluster in Wuhan Urban Agglomeration; (4) The dominant affecting factors of three regional sub-markets of Yangtze River Economic Belt were different. The investment in real estate, the value-added of tertiary industry, and urban population had significant effects on the land prices in Eastern area. In central area, the core factor of the spatial variation of land prices was the value-added of tertiary industry. Meanwhile, the role of administrative grade became prominent. The spatial differentiation pattern of land prices in western area was formed by the administrative grade, the value-added of secondary industry, and urban population.

The official issuance of the Outline of the Development Planning of the Yangtze River Economic Zone has pointed out the direction of regional economic and industrial development, and its industrial transfer and regional cooperation have gradually become the focus of geographical research. Based on the total industrial output value and the number of enterprises of 28 manufacturing industries in 11 provinces and cities of the Yangtze River Economic Zone in 2008 and 2017, this paper explores the transfer of manufacturing industries and regional cooperation in the Yangtze River Economic Zone by means of dynamic agglomeration index, shift-share analysis method (SSM) and static agglomeration index. The research shows that: (1) The labor-intensive and capital-intensive manufacturing industries such as the textile industry, non-ferrous and ferrous metal smelting and rolling processing industry in the Yangtze River Economic Belt have strong spatial transfer characteristics. Their transfer paths are many-to-many diffusive and jumping transfers from Shanghai, Zhejiang to Guizhou and Hunan in the middle and upper reaches of the Yangtze River; The main types of transfer are “advantage transfer type”, “elimination type” in downstream areas and “advantage agglomeration type” in middle and upstream areas.(2) The development of transportation, chemical manufacturing and other industries in the upper and middle reaches of the Yangtze River Economic Zone is relatively weak, and lack of central cooperation areas, which requires more technology financial support from the downstream areas; (3) As the supplier of industrial transfer and technology transfer, the lower reaches of the Yangtze River Economic Belt should be built as the manufacturing transfer center, the middle and upper reaches with industrial comparative advantages as the regional center, increasing the transfer and cooperation of manufacturing industry to the middle and upper reaches of the Yangtze. The research will help to improve the theory of manufacturing transfer and regional cooperation, and provide reference for the manufacturing cooperation and coordinated development of the manufacturing industries in the Yangtze River Economic Belt.

Understanding the impact of land transfer on the economic radiation of urban agglomerations and its formation mechanism, will help scientifically coordinate land planning, effectively regulate the land market, enhance the economic radiation of urban agglomerations, and promote the coordinated development of urban economy. This paper taking 36 cities in Hubei, Hunan and Jiangxi provinces as research areas, using the urban panel data from 2003 to 2016, empirically tested the impact of land transfer on the economic radiation of the urban agglomeration in the middle reaches of the Yangtze River and its formation mechanism with an extended spatial Dubin model. The results showed that: (1) The land transfer has little effect on the economic radiation of the urban agglomeration in the middle reaches of the Yangtze River.Only the central city land transfer has a significant direct spatial effect on the economic radiation of urban agglomerations, while the direct spatial effects of central cities and the indirect spatial effects of non-central cities and non-central cities are not significant; (2) The promotion of land transfer to the economic radiation mainly relies on infrastructure investment, technical efficiency and provincial financial transfer payment mechanism, while enterprise investment and labor mechanism have not formed. The reason is that land transfer has no significant effect on enterprise investment and labor, and there is no significant diffusion effect on enterprise investment, while labor has a backwash effect; (3) To promot the economic radiation of urban agglomeration in the middle reaches of the Yangtze River by land transfer, it is necessary to strengthen the industrial chain invitation of investment in urban co-operation, to accelerating the citizenization of agricultural transfer population.

The essence of China taking the path of independent innovation and the implementation of innovation-driven development strategy is to get rid of dependence on foreign technology and achieve technological independence and leadership. It is an inevitable choice to serve the innovation-driven development strategy by building a technology transfer system that conforms to the law of scientific and technological innovation, thereby accelerating the transfer of technology and the transformation of scientific and technological achievements. Viewing patent transfer as a surrogate for technology transfer, this paper constructs an evaluation model of inter-city technology transfer index based on the multidimensionality of technology transfer, and then builds a division model of inter-city technology transfer system based on the theory of asymmetric interdependence, and thus the spatial-temporal evolution of China’s intercity technology transfer system from 2001 to 2015 was revealed. We first find that from 2001 to 2015, the Beijing-Tianjin region, the Yangtze River Delta region and the Pearl River Delta region were the core triangles of China’s inter-city technology transfer network, and the Chengdu-Chongqing region gradually became a center for technology transfer in the Central and Western regions of China. Therefore, the structure of the quadrangle of China’s inter-city technology transfer network was constructed. Secondly, from 2001 to 2015, China’s inter-city technology transfer system continued to be subdivided, showing the pattern of being directed by Shanghai to Beijing. However, by the end of this study, the grade system of inter-city technology transfer in China has not yet been fully formed.

Research on potential and spatial distribution of reserved urban construction land is the basis for scientifically formulating regional spatial development strategy and optimizing urban development pattern. This paper takes central Jilin Province as a case study to analyze the quantity and spatial distribution of limit potential and effective potential of reserved urban construction land mainly with spatial analysis methods on GIS platform, considering the factors of terrain, land use type, distribution of basic farmland, land use planning, population and urban development. The results show that: (1) the limit potential of reserved urban construction land in central Jilin Province amounts to 14 913.32 km², the values tend to decrease from north to south, which is mainly affected by the administrative region size, climate conditions and geographical environment characteristics; (2) the limit potential utilizing dominance degree index of central Jilin Province is 0.467 8, the values of north parts are higher than that of the south parts, which is closely related with terrain and urban density; (3) the effective potential of reserved urban construction land in central Jilin Province amounts to 2 214.91 km², the major trend of spatial distribution shows that values are high in the middle part, low in the northwest and southwest parts, and medium in the eastern edge part, which is closely related to urbanization level and urban density; (4) the effective potential of reserved urban construction land per capita is 106.65 m² per person, the values are high in the middle part, low in the western edge part, and medium in the edge region of northern, eastern and southern parts, which is mainly affected by urbanization level and urban density, and also has a certain relationship with the population distribution characteristics.

The study on the temporal and spatial evolution of vegetation NDVI and its topographic differentiation effect is of great significance for deeply understanding the relationship between vegetation and human activities, revealing the changes of regional environment and guiding the scientific governance of regional ecological environment. The upper and middle reaches of the Yangtze River Basin was chosen as study area. Based on yearly annual normalized difference vegetation index(NDVI) derived from SPOT sensor, DEM and basic geographical information, the temporal and spatial evolution characteristics and topographic differentiation effect of vegetation NDVI in the middle and upper reaches of the Yangtze River Basin are discussed, and the reasons for its influence are discussed. The results show that:① The ecological environment in the middle and upper reaches of the Yangtze River Basin has been greatly improved from 1998 to 2015. The average annual NDVI of vegetation increased from 0.67% in 1998 to 0.75% in 2015, with an average annual growth rate of 0.57%.② The spatial improvement area of vegetation NDVI (56.82%) was significantly larger than that of degraded area (7.3%), and the improvement area was mainly distributed in the middle and eastern part of the study area. ③ The improvement trend of vegetation NDVI was the highest in the area of 500~1 000 m, 1 000~1 500 m and slope of 8°~15°and 15°~25°, and the degradation trend was the highest in the area of >5 000 m and slope 0°~5 °, and the slope aspect had no significant effect on the change of vegetation NDVI. ④The change of vegetation NDVI in the middle and upper reaches of the Yangtze River Basin from 1998 to 2015 may be the result of the implementation of ecological projects such as natural forest protection, conversion of farmland to forest (grass) and human social and economic activities. ⑤This paper can provide a scientific basis for the treatment and improvement of the fragile ecological environment in the middle and upper reaches of the Yangtze River Basin, and then build an important ecological barrier in the middle and upper reaches of the Yangtze River, and promote the green development of the Yangtze River economic belt.

Ecological red line, also known as “ecological conservation red line, is the bottom line to ensure regional ecological security, which is of great significance for ecological protection. How to establish and improve its performance appraisal and ecological compensation mechanism is currently a problem worthy of attention. This paper takes the ecological red line in chongqing as the research object, and uses the ecological parameters affecting the status of ecosystem services to revise the “ecosystem service equivalent value per unit area in China. ”. The spatio-temporal evolution characteristics and driving factors of ecosystem service value（ESV） in this region between 2000 and 2015 were comprehensively analyzed.The results shows that: ①The main type of ecosystem in in Chongqing ecological red line is forest, accounting for more than 75%; During the period, forest, wetland and artificial surface area increased, while farmland and bare soil continue to decrease.②Among 15 years, ESV in the study area increased by 8.709 billion yuan, an increase of 6.63%, but the growth rate is gradually decreasing.Forest contributes the most to ESV, followed by wetland and grassland. The main types of ecosystem services in the study area are climate regulation and hydrological regulation services, and the ESV of hydrological regulation services has the most significant increasing trend in the period of time. ③The areas with the highest ESV value density are mainly distributed in the middle and low mountain areas such as Daba Mountain, Fangdoushan Mountain, Chuanhegai Mountain, Simian Mountain and Jinfo Mountain. During the period, ESV in the main urban areas such as Four Mountains, Jinfo Mountain and Heishan Mountain, as well as the elite mountains, Huangcaoshan Mountain and Xuebaoshan Mountain in the parallel valleys of Eastern Sichuan, show a marked increasing trend. ESV in the junction areas of Chengkou County and Wuxi County, northern Wushan County, central Fengjie County, northern Pengshui County, southern Qianjiang District, Southern Jiangjin District and southern Qijiang District show a slightly decreasing trend, and ESV in 36 districts and counties increase in the whole city. In addition, ESV decrease in three districts and counties.④Although the wetland area is small, its total ESV is second only to forests, and the ESV per unit area is higher than other types. More attention should be paid to the effective protection of wetlands.⑤Urbanization rate and per capita net income of rural residents are the main driving factors of ESV changes in the study area, which indicates that ecosystem services in the ecological red line are basically coupled with regional social and economic development.

The evaluation of ecological service value is a kind of economic quantitative assessment of ecology function. This paper employed various methods including replacement engineering method, shadow engineering method, carbon tax law, market value method and water balance method to evaluate the ecological services value of the natural resources in the Three Gorges Reservoir (TGR) based on the net primary productivity dataset (NPP), land use/land cover change (LUCC), Remote Sensing data, climate data and statistical data in 2000, 2005, 2010 and 2015, with GIS technology, respectively. And analyze of changes in its temporal and spatial patterns. The results show, from 2000 to 2015, the total value of ecological services in this area increased by 26.937 billion yuan, with a growth rate of 15.32%. The most contribution to total value was made by forest ecosystem with a proportion of 48.14%, followed by cropland with 44.04%. The changing value of forest ecosystem services is mainly correlated with expanding forest area. The area of cropland decreased by 4.64%, whereas the total services value of cropland increased by 14.54%, which means that croplands in this region were used unreasonably. As for grassland, the area decreased by 16.57% along with 5.01% decrease of services value, for which protection of grassland ecosystems should be strengthened. Overall, the implementation of the TGR has a greater impact on the ecosystem services than the disadvantages on the reservoir area globally. Reasonable and efficient land use plan and environment protection plan should be made to ensure the security of the TGR, sustainable economic, and ecological development in the future.

The response of stakeholders to the ecological compensation policy in the environmental protection renovation of the Three Gorges Barrier Area is the endogenous motive force to effectively construct the ecological barrier in the middle and upper reaches of the Yangtze River. Based on the survey data of 608 residents in key emigration counties in the region, the acceptance and willingness-to-pay (WTP)  for the environmental protection attributes such as vegetation coverage, soil erosion, water quality, biodiversity, tourism landscape and their combination schemes of the special subjects (indigenous people and reservoir resettlers) in the region were analyzed by means of Choice Experiments. The results show that both aborigines and resettlers with different economic conditions have strong ecological awareness, but they failed to effectively transform into environmental protection behavior under the pressure of development; the two groups pay more attention to vegetation improvement and water conservation in ecological restoration of reservoir area (104.93 yuan), but pay less attention to species protection and tourism landscape (30.88 yuan) needed for sustainable development; the best combination that immigrants and aborigines are willing to pay is to restore vegetation and conserve soil and water (Plan 5), but the payment level of the former (392.97 yuan) is three times that of the latter (128.02 yuan); the resettlers cannot get enough ecological resources support from the barrier area, so it may be more efficient than a single ecological compensation.

Exploring spatial-temporal variation and influencing factors of rural poverty has important theoretical and practical significance for formulating a reasonable policy to reduce poverty. Taking the incidence of poverty during 2003-2015 in Guizhou Province, this paper makes a quantitative comprehensive analysis of spatiotemporal variation and influencing factors by using the variable coefficient, spatial statistical model, spatial variogram and Bivariate LISA model. Results showed that: 1) The rural poverty in Guizhou Province is deepening as a whole, and the regional differences are increasing. It is spatially high in the east, south, and west, and low in the middle and north. 2) Rural poverty gravity center was between 107.047 2°-107.174 4°E, 26.668 5°-26.713 2°N and was moving to the southeast. The spatial distribution of rural poverty presented a northeast-southwest pattern. 3) The spatial pattern of rural poverty is affected by both random and structural factors. The spatial differentiation is mainly reflected in the south-north direction, while the northwest-southeast direction is more balanced. 4) There is a significant difference in the rural poverty and influencing factors, and the negative correlation between peasant per capita disposable income, per capita grain production and rural poverty is the most obvious. The spatial difference of the Bivariate LISA clustering map between rural poverty and influencing factors are obvious. Finally, from the aspects of coordinating regional coordinated development, formulating differentiated poverty alleviation measures and taking the road of industrial poverty alleviation, this paper also provides a framework for solving rural poverty in Guizhou Province.

Land use transformation research is the current research hotspot and is the most significant area of human activities in Guizhou Province, which is dominated with plateau and mountains. Hence, it is valuable to investigate the interaction between the land use transformation and functional evolution based on arable land in Guizhou Province. Based on the high-resolution remote sensing images during 1966-2016 and field investigations, the present study established the classification system of the function of the land use in the basin and performed the empirical study on the dominant and implicit transition of dam land use, such as the typical basin of Lianjiang in Guizhou. The results can be summarized as follows: from 1966 to 2016, the basin mainly experienced dominant and implicit transformations of land use; the characteristics of the cooperative transformation of cultivated land transformation and functional evolution are obvious, which is dominated by the transformation of resource allocation mode under the transformation of the social and economic development stage of the basin. Case studies suggested that the land use transformation of Guizhou basin can be divided into extensive stages, extensive transition to intensive, gradual intensification and intensification. The three important factors, i.e, “individual, government and market”, “cultural, institutional, socio-economic, and population technology”, are the driving control systems for the land use transformation of the basin.

Water resources vulnerability is an important criterion to measure the carrying capacity of water resources system under the influence of climate change and human activities. And assessment and prediction of water resources vulnerability in river basins is an important means for assessing water security and identifying problems in future water resources systems. Firstly, the evaluation index system of water resources vulnerability in the Yellow River Basin is constructed, and rough set method is used to reduce the dimension of the original index system and remove redundant attributes. Second, the standard value of the dimension-reduced evaluation index is taken as the evaluation sample, and the support vector regression (SVR) model is used to evaluate the vulnerability of water resources in the basin. Finally, three different climate models and socio-economic scenarios are set for scenario prediction of water resources vulnerability in the Yellow River Basin. The results show that the water resources vulnerability of the Yellow River Basin has been raised from level Ⅴ to level Ⅳ in the past 16 years. The water resources vulnerability of the Yellow River Basin under scenario 1 and scenario 2 will be improved in the future, but it is still in the level Ⅳ of moderate vulnerability. In the future, the water quality vulnerability and disaster vulnerability will be improved obviously, and the water shortage vulnerability will not be improved significantly. Under scenario 3, the water quality vulnerability will deteriorate to grade Ⅴ medium-high vulnerability. Therefore, in the future, taking active control measures can make water quality and disaster vulnerability significantly improved, and water shortage vulnerability will become the bottleneck restricting the overall water resources vulnerability of future basins.

Based on 545 daily minimum temperature station data of China from 1961 to 2017 and the “cold degree grade” formulated by meteorological industry, this research studied the spatial and temporal evolution characteristics of different cold weather days in China in recent 57 years from three aspects: climatic state characteristics, trend and fluctuation characteristics. The results showed that: Firstly, the number of cold weather days in China increased gradually with the decreasing of cold grade from 1961 to 2017. The days of extreme cold and severe cold weather were only distributed in high latitude and high altitude areas. With the decreasing of cold grade, the number of cold weather days gradually developed to the south China. Secondly, the trend of cold weather days in different grades in China had different spatial characteristics from 1961 to 2017. The number of high grade cold weather days tended to decrease, mainly in high latitude and high altitude areas. With the decreasing of cold grade, the range of cold weather days tended to increase and decrease continuously. The trend of high grade cold weather days in 1991-2017 was smaller than that in 1961-1990, and with the increasing of cold grade, the areas with larger trend were increasing. Thirdly, the number of high grade cold weather days fluctuated greatly in high latitudes and high altitudes in China from 1961 to 2017. With the decreasing of cold grade, the areas with large fluctuation of cold weather days gradually developed to the south China, and it showed the characteristics of fluctuation high in the South and low in the north. The fluctuation characteristics of moderate and low grade cold weather days in China were respectively concentrated in the Yangtze River Basin and the southern coastal border areas in China from 1991 to 2017. The fluctuation characteristics of high grade cold weather days were mainly concentrated in high latitude and high altitude areas.

Under the combined influence of climate change and regulation of Three Gorges projects, the relationships between Poyang Lake and Yangtze River have been remarkably altered in the middle-lower reaches. A series of existing ecological and environmental problems were induced by the changes of water regimes of Poyang Lake, which have been attracted worldwide attentions. Hence, this study initially investigated the variations of stable water isotopes of precipitation, lake and river water from the channel connecting the Lake Poyang and the Yangtze River, in order to identify the isotopic connections between Yangtze River and Poyang lake water and to analyze the influence of the regulation of Three Gorges projects on the water regimes of Poyang Lake. The results showed that the isotopic compositions of rivers and lakes characterized a remarkably seasonal and spatial distributions, which could be used to reveal the relationship between Poyang Lake and Yangtze River. During the flood regulation period of July, higher δ18O and δ2H values were observed in Poyang lake water compared with Yangtze River water. Moreover, lake water mainly discharged into Yangtze River and its proportion accounted to 75%. During the flood storage dispatching period of November and December, the highest isotopic values were showed due to the stronger enrichment of isotopic compositions. Water level and discharge were obviously changed due to the regulation of Three Gorges projects and affected the relationships between Poyang Lake and Yangtze River. During the flood regulation period, the high water level of the Yangtze River restrained the discharge of lake water. Hence, the water regimes of the Poyang Lake basin should be taken into consideration during the dispatches of the Three Gorges Reservoir, alleviating possible floods in wet seasons and droughts in dry seasons.

Interpretation on the mechanism of solar activity and global climate change on surface hydrological factors provides scientific guidance on the water resource management. This paper has adopted monthly measured runoff and sediment transport data from 1957 to 2015 in the Taojiang River Basin, one of the most important tributaries of the Ganjiang River, and the impact of the relevant global climate index on hydrological factors was discussed with sliding average, correlation, cross-wavelet and wavelet coherence analysis. Results showed that:(1) The correlation between the seven global climatic factors and hydrological factors is different; (2) significant resonance cycles between global climatic oscillation factors and precipitation, runoff, and sediment transport mainly focus on the period of 1.33 - 2.67 a, the significant resonance period between sunspots and precipitation and sediment transport is mainly concentrated around 11a. (3) Sunspot activity has an impact on precipitation in the study area through the “ENSO-Northwest Pacific Anticyclonic(Cyclonic) Circulation-East Asian Monsoon” system. (4) The influence of atmospheric oscillations on the precipitation in the study area is reflected in three aspects: first, Antarctic Oscillation affects precipitation in the study area by affecting the strength of the East Asian monsoon；second, Arctic Oscillation influences the East Asian winter monsoon through the western Pacific subtropical high, thus affecting the precipitation in the study area；third, Pacific-North American Oscillation and North Atlantic affect the winter precipitation in the study area by affecting the airflow and wind anomalies.

Based on the comprehensive meteorological drought index (CI) at 97 meteorological stations and MODIS enhanced vegetation index (EVI) data between 2000 and 2017 in Dongting Lake Basin, the maximum value composites and correlation analysis methods were applied to analyze the spatial and temporal patterns of the EVI (natural and artificial vegetation) and extreme drought intensity during growing seasons (from April to October) over the recent 18 years and to examine the sensitivity of natural vegetation and artificial vegetation to extreme drought. The results show that the inter-annually maximum value of extreme drought intensity and the minimum value of EVI for both natural vegetation and artificial vegetation regions appeared in 2011. The extreme drought intensity during growing season was ranked as that in autumn > in summer > in spring, and EVI varied seasonally in an order of that in summer > in spring > in autumn, but the EVI values of natural vegetation were significantly higher than that of artificial vegetation. The sensitivity of artificial vegetation to extreme drought was higher than that of natural vegetation. However, the sensitivity of both vegetation types to extreme drought varied with vegetation growth stage, with the most significant correlation between the EVI and the extreme drought intensity in August. The extreme drought intensity and EVI can depict well the spatio-temporal evolutions of drought in spring and summer-autumn in 2011.

Clarifying the effects and relative importance of surface parameters on Land Surface Temperature (LST) at different scales can provide a reference for the adjustment and optimization of urban ecological space layout. We used Point of Interest (POI) data to characterize the micro-scale human activity intensity and use the atmospheric correction method to invert the LST of the outer ring region of Wuhan in the summer of 2016. Using Method of Ordinary Least Squares, we quantitatively analyzed the relationships between LST to POI, Normalized Difference Vegetation Index (NDVI) and Modified Normalized Difference Water Index (MNDWI) at 500 m, 1 000 m and 2 000 m scales, then further distinguished the relative importance of variables to LST. The results show that: (1) POI is significantly positively correlated with LST and the correlation coefficient increases with the increase of scale at three scales. NDVI and MNDWI are significantly negatively correlated with LST. The correlation coefficient between NDVI and LST decreases with the increase of scale. The correlation coefficient between MNDWI and LST increases with the increase of scale. (2)The thermal field in Wuhan is the result of the joint action of natural ecological environment and human activities; (3) The interpretation of LST by POI occupies a large relative weight and is the most important factor in the formation of thermal field. The results show that POI has the greatest relative contribution to the interpretation of LST, in the study of urban thermal field influencing factors, POI can be used to reflect the intensity of human activity and has a good complement to remote sensing information.

According to the national standard GB/T 20484-2017 of the People's Republic of China, based on the daily minimum temperature data of 97 stations in Hunan Province during 1961-2016 years, the statistical analysis of cold air activity characteristics in Hunan province shows: (1) The activity cycle of the cold air affecting Hunan is 3-4 d. It is mainly weak cold air, and is 87.4% of the total times. The strong cold air and cold wave are mostly in winter and spring. The frequency of cold air influence is more in the north than in the south in space, and the strong cold air influence is opposite. (2) The spatial distribution of cold air influence in Hunan is the obvious seasonal change. From January to may and October to December, the number of cold air decreases from north to south; June and September are adjustment periods; From July to August, the spatial distribution of cold air impacts is increasing from north to south. (3) There was no significant change in the number of cold air impacts in Hunan Province during 1961-2016, but the interdecadal variation was obvious. The times of severe cold air influence showed significant decreasing. (4) The cooling range of the cold air process in Hunan Province showed significant decreasing during 1961-2016; The duration of the cold air process presented insignificant increasing. The duration of the cold air influence process in Hunan was in 5d. The proportion of cooling air temperature greater than or equal to 8℃, 10℃, 12℃ of the cold air lasted for 3 d was the largest. (5)Compared with 1961-1980, the average cooling range in the most counties (cities) of Hunan was decreasing during 1981-2010, and the average duration of cooling was increasing.

The water used by residents in the red bed area of Sichuan province is mainly the groundwater extracted nearby，and the water quality is uneven.Therefore，the study on the hydrogeochemical characteristics of the red zone groundwater is of great significance for the selection of well-suited areas and the water safety of the red zone water source.Taking Suining Chuanshan district as an example，this paper analyzes the hydrochemical characteristics and main ion sources of the red shallow groundwater in suining district by means of mathematical statistical analysis，ion proportion relation and mineral saturation index of 70 groups of shallow groundwater samples collected． The results show that the anions in the groundwater of the study area are mainly HCO₃^-（164.00~571.91 mg·L^-1），the second is SO₄^2-（13.96~1 000.00 mg·L^-1），the cations is Ca₂⁺（45.70~313.00 mg·L^-1）；The ion composition in groundwater is mainly produced by rock weathering，and comes from the weathering and dissolution of calcite，dolomite，gypsum，mirabilite and other minerals in the strata，and at the same time evaporates and concentrates．The quality of shallow groundwater is mainly of type III~IV.The main pollutants are primary pollution such as TDS，Fe₃⁺，and human activities such as NO₃^-，NO₂^-and so on.The suitable wells for red beds are mainly in the areas of flat dams，hillsides and valleys.In order to avoid exceeding the pollution index，the depth of wells should not exceed 25 m，and groundwater far away from aquaculture farms and agricultural latrines is vulnerable to human beings.Active pollution of the environment，prevent fish ponds，farmland and other surface water into wells.

Indicator 15.1.2 of the United Nations 2030 Sustainable Development Goals (SDGs) cannot be effectively applied to county-scale assessments due to the scale and availability of the metadata. In order to solve this problem, a set of assessment indicator system for biodiversity was constructed by using remote sensing data and methods, it considered the connotation of biodiversity, based on the consideration of county scale calculation. The results show that the implementation of SDG 15.1.2 in Deqing County was good, and the biodiversity index could effectively monitor the status and changes of biodiversity at County scale. This study is helpful for calculating and evaluating the progress of implementation of SDG 15.1.2, and provides precise reference information for grassroots administrative regions to achieve sustainable development goals.

For accurately predicting foliar uptake of the Naphthalene (Nap), Phenanthrene (Phe), Fluorene (Fl) and Pyrene (Pyr), leaf cuticle of Pinus massoniana，Pittosporum. Tobira and Osmanthus fragrans were isolated by chemical methods. Adsorption behavior of PAHs onto leaf cuticle was investigated and the their influence factors. The three tree species cuticle were obtained by means of the chemical separation. The results showed that the distribution of PAHs was mainly responsive for the absorption of Nap, Phe, Fl and Pyr. According to the value of Kd, which was the by the rate of linear isothermal adsorption curve, three tree species had a strong sorption capacity of Nap. P. tobira had a stronger sorption capacity than O. fragrans and P. tobira. P. massoniana had an similar adsorption capacity of Phe compared with O. fragrans, but stronger than that of P. tobira. P. massoniana had a stronger sorption capacity of Fl than O. fragrans and P. tobira. O. fragrans had a stronger sorption capacity of Pyr than P. massoniana and P. tobira. An scanning electron microscope (SEM) observation revealed that the P. sylvestris cuticle has a rich microstructure, with stoma distributed densely on both sides. The surface of O. fragrans cuticle had rough folds, whereas P. tobira cuticle was smooth. However, we did not observe an obvious stoma in both P. tobira and O. fragrans cuticle. The differences in the leaf microstructure of plant cuticle were major causes of the interspecies difference of PAHs (polycyclic aromatic hydrocarbons, PAHs) adsorption. A Fourier transform infrared (FTIR) analysis revealed that P. massoniana contained fatty components, with the highest lipid content among the three trees. We also observed signals of three plant cuticle in C=O (~1 734 cm^-1), indicating an obvious absorption peak of ester bond. Moreover, C-O-C peak (~1 057 cm^-1) is most prominent, which related to sugar content.

The formal promulgation of“the Law on the Prevention and Control of Soil Pollution”marks that the target of prevention soil pollution in China has changed from "current situation control" to “risk early-warning”. Therefore, it is of theoretical and practical significance to carry out regional soil heavy metal risk warning research. Based on the soil survey data of a grain-producing county along the coast of Taihu Lake in 2015, this study use heavy metal input-output flux model and soil environmental capacity method to calculate the risk probability of five heavy metals in 2030 (15 years later) and 2050 (35 years later). The results show that atmospheric dry and wet deposition becomes the main source of  four heavy metals apart from As. Livestock manure, fertilizer input and irrigation water will also affect soil heavy metal input to some extent. In addition, the three heavy metals of As, Cr and Pb in the cultivated soil of the study area are relatively good, and the risk of Hg and Cd pollution is slightly high, mainly distributed in O town and town P in the middle of the study area. The combination of GIS technology and regional material flow model can provide a good risk warning for different regions and different heavy metal pollution types, which can provide important ideas for the formulation of soil pollution differentiation management strategy.

In February 2015, the Ministry of Agriculture formulated the Zero-growth Action of Chemical Fertilizer Use by 2020. In order to deeply analyze the role of this policy in the reduction of agricultural non-point source pollution and the improvement of agricultural origin environment, this paper simulates the application of chemical fertilizers in China without the implementation of the action by means of grey GM (1,1) model and decoupling theory, and explores the contribution of the action to the reduction of agricultural non-point source pollution in China. The results showed that: (1) The actual application of fertilizer in China has significantly decreased compared with the simulated value; The actual application of nitrogen fertilizer, phosphate fertilizer and compound fertilizer was reduced to different degree, in which the growth rate of compound fertilizer was slowed down, but still showed a growth trend. (2) the Zero-growth Action of Chemical Fertilizer was of great significance to the prevention and control of agricultural non-point source pollution; Within three years of the implementation of the action, the reduction of fertilizer pollution emissions accounted for more than one-fifth of the total emissions in 2014. (3) After the implementation of the action, the dependence of China’s agricultural economic development on chemical fertilizer input was greatly weakened; in recent years, there has been a strong decoupling between the two, showing a reverse change. (4) From the perspective of fertilization structure, nitrogen fertilizer and phosphate fertilizer went from weak decoupling into a strong decoupling state, and maintained basic stability; Although the decoupling index of compound fertilizer decreased, it still did not change the weak decoupling state. (5) On the spatial level, the decoupling between agricultural production and non-point source pollution of fertilizer in all provinces and regions was generally better. The dependence of agricultural production on fertilizer input in northeast, southwest and southeast regions was gradually weakening, and major agricultural provinces such as Shandong and Jiangsu have completely achieved decoupling. Finally, the paper puts forward some suggestions from the perspectives of improving the utilization efficiency of fertilizer, adjusting the structure of fertilizer application and optimizing the statistical system of agricultural industry, so as to provide reference for the government to formulate relevant policies.