Based on the monthly monitoring of the northern of the Qingmuguan undergroundwater from March,2008 to October,2008,and the monthly monitoring of the southern of the Qingmuguan groundwater from June,2010 to October,2010,using hydrochemical and 15N isotope techniques,variations of nitratenitrogen and its possible sources were investigated.The results showed that the nitrate concentrations were 2035 mg/L and 5077 mg/L at the outlet of the north and south underground river,and were 320 mg/L and 0842 mg/L at the inlet of the river.The outlet of the two parts were all 6 times more than the inlet of them. In addition,through analyzing the spatial distribution of δ15N in the whole underground river basin,it could be concluded that the southern of the underground river had high NO-3δ15N,and changed significantly.The maximum value(37825‰)appeared in the Dingjia cave sampling point on September 21.The nitrate source might be waste and sewage.The northern of the underground river had low NO-3δ15N and a small rangeability.δ^15N data were all bellow 10‰.The source of the nitrate were soil organic nitrogen and nitrogen in agriculture

In recent years, the frequent outbreaks of mountain floods have seriously threatened peoples' lives and property. Risk analysis such as flooding susceptibility assessment is one of the critical approaches to prevent and mitigate flooding disaster. However, the inadequate field survey and lack of data might become the significant challenges for the mapping of flood susceptibility. In the era of big data, user-generated data provides new opportunities for flood risk management. This paper takes Ji’an City as the focus area, using the flooding disaster data generated by users on the Internet. 70% flood events were randomly selected as training sample and eight flood-conditioning factors including elevation, slope, aspect, curvature, rainfall, river distance, land use and normalized vegetation index were chosen to evaluate the flooding disaster by logistic regression model. The confusion matrix and ROC curve were used to verify the evaluation results. The results show that: (1) The area with low terrain, close to water system, large rainfall, and construction land have a higher probability of flood occurrence. (2) According to the confusion matrix, the overall accuracy rate of classification is 80.6%.Verified by ROC curves, the AUC value of the training sample and the validation sample is 0.888 and 0.980 respectively. The AUC values are both greater than 0.8, indicating that the evaluation accuracy of the model is relatively high. (3) The proportion of high-risk and extremely high-risk areas is 28.71%, including 80.99% of the flood events in the study area, which shows these areas are densely distributed and highly susceptible. The evaluation outcomes were consistent with the actual situation based on the verification of the flood events from June 1 to June 8, 2020. It can be concluded from the results above that it is feasible to use the data generated by users on the Internet in mountainous areas where the data is not easy to obtain, and the evaluation results can be used to land use planning and flood risk management in Ji'an city.

The construction of ecological network pattern is one of the important ways to ensure regional ecological security, to coordinate economic and social development and ecological system contradictions, and to enhance human well-being. This study takes Anqing City as an empirical area, identifies the regional ecological sources by evaluating the ecosystem service functions, and then uses the circuit theory to construct the ecological network pattern, demonstrates the regional ecological network structure characteristics according to the current density, and finally proposes the regional ecological network and Ecological security optimization strategies. The results of this study indicate that the ecological network structure of Anqing City is mainly composed of 24 source sites larger than 1 km2, 3 potential corridors, 23 pinch points and 3 important obstacles. The ecological sources are mainly composed of forest land and cultivated land. The areas with better ecological resources are mainly distributed along the Dalongshan Forest Park in the north of the city, the edge area of the eastern development zone and the western farm area. The ecological resource flow in the central urban area is blocked, the ecological corridor connectivity is poor, and the ecological network pattern is significantly heterogeneous. This study analyzes the ecological network security under different thresholds, proposes the ecosystem improvement and restoration strategies under different network patterns, and has positive practical guiding implication for improving the supply capacity of regional ecosystem services and the connectivity of ecological networks.

In recent years, with the rapid economic development of the Yangtze River Basin, the local government has attached great importance to the deterioration of the water quality of Nanyi Lake, the lake of the South Bank of the lower reaches of the Yangtze River. In this study, 39 samples were collected from surface sediments of the whole lake area and 6 surface water samples from the main inlet and outlet tributaries, and the contents and distribution patterns of heavy metals As, Cr, Cu, Mn, Ni, Pb, Zn and the contents of TOC and TN in the sediments of Nanyi Lake were analyzed.The pollution degree and ecological risk of heavy metals in sediments were evaluated, and the pollution sources of Nanyi Lake were analyzed by principal component analysis and correlation analysis.The results showed that the average concentration of Pb in interstitial water exceeded the Criteria Continuous Concentration (CCC) of the National Recommended Water Quality Criteria.The average contents of As, Cr, Cu, Mn, Ni, Pb and Zn in sediments were higher than the river background value in the Jianghuai River Basin of Anhui Province, and the multiples exceeding the background value were Pb (3.36)>Mn (2.74)>Zn (2.51)>As (1.80)>Cu (1.40)>Ni (1.34)>Cr (1.13). Fractions of heavy metals analysis showed that As, Cr, Ni and Pb existed mainly in residual fractions (F4), while Zn was dominated by the non-residual fraction ( F1 + F2 + F3) with a mass fraction of 54%, and the reducible fraction (F2) of Mn was 37.4% in East Lake, the sulfide and organic matter bound state (F3) of Cu in the West Lake accounted for 26.7%. The potential ecological risk assessment method of heavy metals showed that Pb was a medium-risk in 13 sampling site. The average value and order of heavy metal partition coefficient (lgKd) in sediments were Cr (4.80)>Zn(4.50)>Cu(4.43)>Pb(4.37)>Ni(4.31)>As(4.27)>Mn(2.73). The principal component analysis and correlation analysis and spatial distribution showed that the water pollution of Nanyi Lake mainly came from the industrial wastewater collected by the rivers entering the lake, aquaculture and aquatic biodegradation in the lake, as well as the non-point source input from the surrounding agriculture and residents' lives. Based on the high ecological risk of Pb in the whole lake area, we should continue to pay attention to the impact of heavy metal Pb on the water environment and ecosystem of Nanyi Lake.

It is of theoretical and practical significance to explore the spatial and temporal changes of carbon stocks in regional terrestrial ecosystems over long periods of time and their influencing factors to achieve the carbon neutrality goal. This study couples the PLUS-InVEST-Geodector model to investigate the spatial and temporal changes of carbon stocks in the Three Gorges Reservoir Area under different scenarios from 1990 to 2035, and to quantitatively reveal the attribution factors affecting the changes of carbon stocks from the perspectives of land use changes and natural-socio-economic complex relationships. The results show that (1) the carbon stock in the Three Gorges Reservoir Area shows a fluctuation of “decrease-increase-decrease” from 1990 to 2020, with an overall decrease of 6.66 Tg, or 1.25%, among which a large area of arable land is transferred to construction land as the main reason for the decrease of carbon stock; (2) The spatial distribution of carbon stocks in the Three Gorges Reservoir Area from 1990 to 2035 is highly consistent with land use changes, and its spatial heterogeneity is significant, showing the distribution characteristics of “high in the east and low in the west, low in the south and high in the north, and head of the reservoir > belly of the reservoir > tail of the reservoir”. (3) The carbon storage of the natural development scenario and the ecological protection scenario in 2035 will be reduced by 7.53 Tg and 0.37 Tg respectively compared with the year 2020, and the ecological protection scenario can significantly reduce the carbon storage loss in the reservoir area compared with the natural development scenario; (4) The factors affecting the spatial and temporal changes of carbon storage are significant, among which land use change is the dominant factor, followed by temperature, population density, elevation and soil type, and the interaction of all factors increases the explanatory power of carbon storage changes. This study can provide scientific reference for the management of carbon pools in the reservoir area and the sustainable development of carbon storage function.

It is an efficient method of water environment survey to using remote sensing data for large area water quality monitoring.The Poyang Lake was selected as the research area in this research. The chlorophylla content which gives an important index to eutrophic state of water was chosen as the study object. The water reflectance spectra were acquired with an ASD FieldSpec HH (3501050nm) and the MODIS data collected during the same period. Based on MODIS data, the range of the Poyang Lake was extracted by a approach named Floating Algae Index (FAI).After the measured spectra were preprocessed with deleted abnormal data,normalization and Spectral derivative,the relation between the spectral reflectance of the Poyang Lake and the corresponding moment of the chlorophylla concentration were analyzed in spectral index method which was structured by band difference,ratio and the normalized [JP2]difference.The sensitive band scope
was harvested,including the band intervals of 673-680 nm and 650-665 nm,680-710 nm and 650-670nm,662-671 nm and 700-720 nm. Then the optimum bands combination [JP]was chosen. At last the inversion model of MODIS data for chlorophylla concentration of the Poyang Lake was achieved,and the correction coefficient was 0.67. Applying the model,the chlorophylla concentration distribution map of the Poyang Lake in the autumn of 2011 was given. The result showed that the chlorophylla concentration of the Poyang Lake was not high,and in spatial distribution the chlorophylla concentration was higher at the border of water and land than at the center of lake. The analysis supports that the spectrum of the Poyang Lake has been known by quantitative analysis of the measured spectra,and the long wave drift of spectral reflectance phenomena is revealed. A method of remote sensing to monitor chlorophylla concentration the for Poyang Lake which is of low eutrophication and unevenly distributed is established. Meanwhile it provides a forceful scientific guidance for water environment management of the Poyang Lake

Urban ecological resilience construction is the key for the high-quality integrated development of the Yangtze River Delta. This paper constructs an ecological resilience evaluation model from the three dimensions of resistance, adaptability and recovery to study the spatial- temporal evolution characteristics of urban ecological resilience in the Yangtze River Delta from 2011 to 2019; and analyzes the spatial-temporal heterogeneity of ecological resilience influencing factors by using the geographically and temporally weighted regression (GTWR) and STIRPAT (the Stochastic Impacts by Regression on Population, Affluence, and Technology) extended models. The results show that： (1) From 2011 to 2019, the ecological resilience index of Yangtze River Delta cties showed an overall fluctuating upward trend, with the number of fluctuating declining or stagnant cities accounting for a small proportion and the fluctuating low-rate rising cities dominating; the resistance of ecological resilience of cities was higher than the adaptability and recovery, and the resistance of ecological resilience showed a fluctuating downward trend during the study period while the adaptability and recovery fluctuated upward. (2) The ecological resilience high value zone of the Yangtze River Delta experienced the evolution process of “overall dispersion and partial agglomeration-small agglomeration and large dispersion-small agglomeration and large dispersion strengthening-Multi-location clustering”. (3) The results of the GTWR model showed that there were obvious spatial and temporal differences among the influencing factors, and the intensity and fluctuation direction of the influencing factors varied in different regions.

Danjiang River Basin is an important water source of the middle route of South to North Water Transfer Project. The water quality and quantity in Danjiang River Basin are crucial for the water safety of Beijing, Tianjin, Hebei and Henan. In order to reveal the response of runoff and sediment to land use change in the Danjiang River Basin, this paper quantitatively analyzed the changes of runoff and sediment under different land use scenarios by using Soil and Water Assessment Tool (SWAT ) model and land use data from year 2000, 2008 and 2018. The results showed that: (1) During the period from year 2000 to 2018, the area of cultivated land decreased by 1 400.98 km2, while the area of forest land, grassland, urban land, and unused land increased by 938.20 km2, 400.04 km2, 43.53 km2 and 12.44 km2 in Danjiang River Basin, respectively. (2) The SWAT modeling results showed that the decrease of runoff and sediment could be due to the decrease of cultivated land and grassland area and the increase of forest land. During scenario year 2000 to 2008, land use change casued a reduction of 27 million m3 (-2.16%) in averaged annual runoff and a reduction of 11 900 tons (-6.74%) in averaged annual sediment, respecitivly. During scenario year 2008 to 2018, land use change caused a decrease of 168 billion m3 (-13.73%) in averaged annual runoff and 89 700 tons (-54.46%) in averaged annual sediment, respectively. (3) The water yield of Danjiang River Basin is higher in the upper and lower reaches while lower in the middle reaches; The sediment yield is lower in the upper and middle reaches while higher in the lower reaches. This study can provide a scientific basis for the optimization of land use strategy and the protection of water and soil resources in Danjiang River Basin.

Farmers are both builders and beneficiaries of the rural living environment. Their active participation and initiative are great guarantors of successfully promoting the improvement of the rural living environment. Based on the theory of perceived value and stimulus-organism-response (SOR) model, the theoretical analysis framework of farmers' willingness to participate in rural habitat improvement was constructed from the angles of both social capital and perceived value. The empirical test was carried out through farm household research data in Jiangxi Province. The results showed that: (1) Social network, social trust and social norms had a significant positive effect on the willingness of farmers to participate in the improvement of rural human settlements, with the social network effect being the largest. Functional value, emotional value and cognitive value all had a significant positive effect on the willingness of farmers to participate in the improvement of rural habitat, with functional value obtaining maximum effect. (2) Social network significantly affected the level of functional, emotional, and perceived value. It was shown that social network was the most critical factor influencing farmers' perceived value. (3) Perceived value played a partly intermediary role in the influence of social capital on farmers' willingness to participate in rural habitat improvement. On these grounds, in the process of promoting the improvement of rural human settlements, it is necessary to make great efforts to cultivate the social capital of rural households and to raise the level of their perceived value of the improvement of rural living environment governance, so as to increase the motivation of farmers to participate in the improvement of rural human settlements.

The function of the national ecological security barrier in Three-River-Source National Park is prominent, so it is of great significance to construct and optimize its ecological security pattern. Based on the land use and remote sensing data in 2020, and the morphological pattern spatial analysis method (MSPA), we constructed the ecological sensitivity evaluation system. In addition, we extracted the important ecological corridors and potential ecological corridors to form the ecological security pattern of Three-River-Source National Park. The functions of the ecological security pattern were optimized using the minimum cumulative resistance model and the gravity model. The results are as follows: (1) The ecological source area of Three-River-Source National Park was 26 833 km2, accounting for 21.80% of the total area. (2) A total of 9 important ecological corridors (536.62 km) and 55 potential ecological corridors (6 080.15 km) were extracted, among which 45 potential ecological corridors (5 124.17 km) and 8 important ecological corridors (522.10 km) were extracted from the Yangtze River Source Park and Lancang River Source Park. Meanwhile, 10 potential ecological corridors (955.98 km) and 1 important ecological corridor (14.52 km) were extracted from Huangheyuan Park. (3) Optimization of the ecological functions of Three-River-Source National Park results in a core protection area (39 613.58 km²), an ecological conservation area (67 261.84 km²), a recreation exhibition area (10 143.44 km²) and a traditional utilization area (6 081.34 km2), accounting for 32.18%, 54.64%, 8.24%, and 4.94% respectively. The results provided reference value for the spatial planning of Three-River-Source National Park and future function optimization of national ecological security barriers.

A field survey in Lake Taihu was performed from May 2019 to September 2020 before a full fishing ban was implemented. We analyzed the community structure and diversity of fish by using Shannon-Wiener diversity index, Margalef’s species richness index, Pielou’s evenness index, analysis of similarity and abundance-biomass comparison curves. In total, 65 species were collected, belonging to 51 genera, 17 families, and 9 orders. Cyprinidae had the largest number of species, accounting for 55.38% of the total species captured. Tridentiger trigonocephalus and Anguilla marmorata were first recorded in Lake Taihu. Settled fish species were the most frequent of the three ecological groups, and pelagic fish species were the most frequent of the three habitat types, whereas carnivore and omnivore fish species were the most frequent of the five feeding functional groups. The catch per unit effort (CPUE) using gill net and cage net were 4 287.03±515.94 and 626.32±91.24 g·net^-1·12h^-1, respectively. Coilia nasus, Carassius auratus, and Cultrichthys erythropterus were the dominant species. The mean values of Shannon-Wiener diversity index, Margalef’s species richness index, and Pielou’s evenness index were 2.34, 2.10 and 0.68, indicating that its fish diversity level was moderate, with the fact of miniaturization of fish. ANOSIM (analysis of similarity) revealed that the fish species composition of Lake Taihu varied significantly in spatio-temporal distribution patterns (P<0.05). Abundance-biomass curves (ABC) of fish community indicated that the community was seriously disturbed. The study can provide a scientific basis for protection and management of fishery resources in Lake Taihu.

The emerging and popularity of distributed hydrological models promote the development of hydrology sciences meanwhile massive model parameters are introduced, emphasizing the necessity of screening out sensitive parameters. Sensitivity analysis（SA) helps recognize sensitive parameters, reduce the number of model parameters to be analyzed and facilitates parametric optimization and uncertainty estimation. In this study the Xin’anjiang model was applied to Gaotan catchment located in the upstream of Han River basin and Nash-Sutcliffe efficiency（DC), water balance coefficient（WB) and their combination served as objective functions to evaluate the accuracy of daily streamflow simulation. A qualitative SA approach, Morris method was first used to screen out sensitive parameters and reduce the dimensionality of model parameters. The Sobol method was then adopted to quantify degrees of sensitivity of sensitive parameters quantitatively. Both methods are implemented for three different objective functions. The result showed that among 13 selected model parameters, runoff generation parameter KC, runoff separation parameters SM and KI/ KG, runoff routing parameters CI,CG and CS are identified as sensitive parameters, among which KC is most sensitive. Furthermore, the selection of objective functions to be evaluated has significant impact on the determination of sensitive parameters: water balance coefficient is most sensitive to KC while Nash-Sutcliffe efficiency more sensitive to other sensitive parameters, especially CS. Further investigation into sensitive parameters revealed that some parameters like SM have higher interaction sensitivities compared to first-order sensitivities, indicating that the interactions between model parameters should be regarded as an unnegligible factor of parameters sensitivity. The Morris method facilitates the reduction of dimensionalities of model parameters while the Sobol method precisely characterizes the features of parametric sensitivities and provides more information on the sensitivities. The integration of both methods is demonstrated to enhance the reliability and accuracy of sensitivity analysis.

Green innovation is a new driving force for high-quality development, and the spatial differentiation of green innovation efficiency is related to higher-quality integration in the Yangtze River Delta. This paper selects the data of 41 cities in the Yangtze River Delta from 2006 to 2017, uses the SBM model to measure the efficiency of urban green innovation, using Theil index and Hurst index to describe the temporal and spatial characteristics of green innovation efficiency, and selects the Tobit model from “environment-economy-policy” three dimensions to systematically discuss its influence mechanism. The result showed that: (1) The volatility of urban green innovation efficiency in the Yangtze River Delta region is rising, regional differences are gradually decreasing, and the regional coordinated development trend is obvious. (2) Efficient “depressions” has appeared around some core cities in the Yangtze River Delta, and high-efficiency distribution areas have transformed from regions with superior natural endowments to regions with high technical and industrial structure. (3) The green innovation efficiency of cities in the central part of the Yangtze River Delta is at risk of continuing to decline. The eastern coastal zone and the cities in the outer circle of Jiangsu Province are the main areas of continuous growth, which are distributed in bands and rings. (4) Economic factors and policy factors have a higher degree of explanation for green innovation efficiency than natural factors. Factors such as urban economic strength, industrial structure, and environmental regulations play a particularly significant role, but the effects of each factor show phased differences. This has provided scientific support for formulating innovation-driven green development policies tailored to local conditions and promoting higher-quality integrated development in the Yangtze River Delta.

In order to clarify the composition of bacterioplankton communities and the environmental factors involved, we collected samples of bacterioplankton and monitored some main environmental indexes in February 2018 and July 2018 respectively in the Daye Lake. Basing on 16S rRNA high-throughput sequencing, we analyzed and compared the differences in composition and diversity of bacterial communities in the Daye Lake during the dry season and the wet season. We conducted the redundancy analysis (RDA) to explore the relationship between environment factors and composition and diversity of bacterial communities in the water. The results showed that the bacterioplankton had high microbial diversity in the Daye Lake. The Shannon indexes of dry season and wet season were 3.856±0.642 and 4.165±0.608, respectively. The main bacterial categories were Proteobacteria, Actinobacteria, Cyanobacteria, Bacteroidetes, Firmicutes, Planctomycetes, Verrucomicrobia, Chlorobi and Chloroflexi. In this case, the dominant bacteria was Betaproteobacteria (44.73%) in dry season. In wet season, however, the dominant bacteria were Cyanobacteria (31.39%) and Actinobacteria (31.37%). Redundancy analysis showed that nitrate (NO^-₃-N), temperature (T) and total nitrogen (TN) were the main environmental factors affecting the distribution of bacterial communities.

The environmentally friendly behavior of tourists is of great significance to the environmental protection and sustainable development of tourist destinations. The fit of tourism environment and local attachment have an important impact on the environmentally friendly behavior of tourists. Based on the tourism environment fit degree theory, this study uses the world heritage site Wulingyuan as the data survey place, and through a questionnaire survey of more than 1 000 tourists who are or have been traveling in Wulingyuan,, AMOS structural equation model is used for multilevel hypothesis test and intermediary effect test, to clarify the impact mechanism of tourism environment fit on tourists’ environmental behavior. Study has shown that the direct influence of tourists ’environmental compatibility on tourists’ environmental behavior is not significant. The degree of tourism environmental fitness positively affects local attachment, and local attachment also has a positive impact on environmentally friendly behavior. Local attachment plays an intermediary role between tourism environment fit and pro-environmental behavior. Based on these, it puts forward management suggestions to the scenic spots of the heritage sites, guides tourists’ environmental-friendly behavior, and promotes sustainable tourism development.

This paper discussed the ecological restoration of a reclaimed riparian wetland, using the example of Xinji Riverine Island located inside the Yangtze River, with GIS/RS tools and a sixlevel framework. The reclaimed island was strongly anthropogenically disturbed, resulting in a change of structure and process of the riverine island landscape as well as a decrease of its ecological services. The ecological approach considers the physical and biological factors to represent landscape’s ability to support riparian wetland ecosystem services. Three scenarios, namely maintaining the status quo, removing the ponder dyke, and removing all flood embankments, were established to select the best solution.We estimate the impact of the different scenarios on the wetland area and the habitat, which points out that the extensive removal of all flood embankments would result in an increase of wetland area with 5% to 56% and an increase in the habitat for fishes, chelonians, limpkins with respectively 7%, 11%, 5% to 21%, 75%, 56%. We suggest the extensive removal of the anthropogenic disturbance, which would restore the natural flooding cycle, the temporary wetlands and habitat. The approach creates a precedent for the ecological restorationof other riverine wetland systems under anthropogenic disturbance

In order to explore the soil quality and influencing factors of cultivated land in the north of Hubei province, Zaoyang City, Hubei Province was selected as the research area, 240 samples were selected, soil organic matter (SOM) was the research object, and classical statistics and geostatistics were used. Analyzing the spatial pattern of cultivated land SOM, introducing the geodetector Geodetector model combined with the Pearson correlation coefficient method to calculate the significant factors affecting the spatial pattern of SOM content in Zaoyang City. The results showed that: (1)The spatial distribution of SOM content in cultivated land in Zaoyang City showed weak variability, and the spatial variability model was fitted by a spherical model; (2)The distribution pattern presented a spatial pattern of high surroundings and low center to northeast; (3)The five factors that have the strongest impact on SOM single factor are precipitation, soil type, NDVI, surface undulation, and highway distance. The explanatory power of each factor interaction is greater than the explanatory power of the single factor action, showing a nonlinear synergy. This study combines geographic information science with remote sensing, statistics, and geographic detectors, and other multidisciplinary technologies, to provide methods to explore the spatial pattern and factors of soil nutrients in the hilly land of northern Hubei, and try to provide agriculture for rice planting areas and basin areas. Management, fertilization control, and spatial prediction of soil nutrients provide the basis for research work.

Water resources are the lifeline of economic and social development, Xinjiang has been facing severe water shortage and eco-environmental vulnerability for a long time. Hence study the carrying capacity of water resources and it’s spatial-temporal characteristics in Xinjiang has become an urgent problem to be solved. This paper select the evaluation indexes of water resources, social, economic, ecology and coordination system, calculates the comprehensive evaluation index of water resources carrying capacity by building a comprehensive evaluation model of water resources carrying capacity in fifteen regions in Xinjiang. In addition, the spatial-temporal distribution characteristics of water resources carrying capacity are analyzed. The result showed that: Tarbagatay Prefecture, Altay Prefecture and Bayingol Mongolian Autonomous Prefecture classified as the suitable carrying capacity area, Shihezi City and Karamay City classified as the grossly overloaded area, Aksu prefecture and Kashi prefecture classified as the lightly overloaded area, the other eight regions belong to the edge of the overloaded area; From the perspective of development trend, the edge of the overloaded area and the lightly overloaded area have been decreased slightly, while the suitable carrying capacity area have been increased slightly. Generally speaking, the most regions of Xinjiang’s water resources carrying capacity are on the edge of the overloaded area, the coordination level of water resources and socio- economic is generally low, the distribution of water resources are extremely unbalanced, and the distribution of water resources did not match with the distribution of population and economic development. But in nearly ten years, the comprehensive level of water resources carrying capacity shows a better development trend in most regions in Xinjiang. Finally, the policy suggestions are put forward to improve the carrying capacity of water resources.

As the basis of food production, arable land is the root of the survival and development of human society, and its utilization efficiency has profound influence on the development and progress of human civilization. In this study, southwest region in china including Chongqing city, Sichuan province, Guizhou province and Yunnan province as a case study, and based on the dataset in 2000, 2005, 2010 and 2015, the DEA model was used to simulate the efficiency of arable land. Then, the global and local spatial pattern in different period of the arable land use efficiency had been analyzed by the method of global Moran’I, trend surface analysis and G*i index, respectively. At last, the main factors that influence the spatial differentiation of arable land utilization efficiency were evaluated by the method of geography weighted regression (GWR). The results showed that, firstly, between 2000 and 2015, the number of cities in high value areas of arable land utilization efficiency was expanding. Specifically, in the spatial distribution, the efficiency was stable, and the high value region mainly distributed in Dazhou-Deyang-Chengdu-Ganzi in Sichuan province. Sichuan province had maintained high efficiency and changed little; while, the efficiency in Chongqing city increased over time. The efficiency in Guizhou tended to decline, while Yunnan province remains inefficient. Secondly, the efficiency was mainly the positive spatial autocorrelation, and the spatial distribution trend increased from west to east, as well as the increase trend of the “U” pattern from south to north. Remarkable comprehensive of efficiency spatial pattern of differentiation, and relatively higher value/lower value of efficiency presented strong aggregation depended on the space distribution, cold/hot spatial pattern polarization phenomenon more obvious, clearly line and hierarchy. Change over time, the region of cold/ hot spots on the spatial pattern had changed from the “group” pattern to the “tape” pattern. Thirdly, the spatiotemporal change of the arable land utilization efficiency was the largest affected by driving factors of the per capita net income of farmers, followed by the multiple crop index; the effect of cultivated land quality and irrigation index was similar; the influence of per capita GDP to cultivated land use efficiency increased year by year; while, the effect of terrain factors decreased year by year.

Polarized area is an urbanintensive region,which has an important national strategy and has an important function of international competitiveness in one country. In the context of globalization and increasing economic cooperation and competition between countries,all over the countries in the world are trying to focus on constructing the polarized areas as a way to enhance the competitiveness among their counterparts.In this paper,after reviewing the indicators of evaluation on the functions of polarized areas in Germany,which includes decisionmaking and control functions,innovation and competitiveness and gatewayfunction,the writers put forward the contents and indicators to identify the polarized areas and their relevant functions in China.Based on the theory of polarized area,this paper also assesses and makes a comparison among the functional orientations in the regional planning of the Yangtze River Delta,Pearl River Delta and BeijingTianjinHebei Metropolitan Region.In the last two years,in order to increase the level of urbanization,promote the regional coordinated development,and improve the international competitiveness,the State Council of China has approved several regional planning which have national strategic significance.However,according to the definition and the evaluation criteria,this paper argues that,currently the regions like the Yangtze River Delta,Pearl River Delta and BeijingTianjinHebei Metropolitan Region are already polarized areas in China having strong international competitiveness,and some of them could be fostered to the polarized areas,while the others have not qualified to the polarized areas,and just to balance the development of the Eastern and Western,or for the aim of ecologic protection of China.Finally,the authors discuss some preliminary advice regarding the first two strategic areas,which is provided to foster their relevant function in the way of polarized areas development

Compared with the traditional industries,new and high tech industries has more strongly inherent requirement for geographic concentration,which leads to the significant difference in geographical pattern.The article attempts to study the status of new and high tech industries geographical pattern and geographical concentration and the change trend separately from the industry as a whole and subsectors from the perspective of geography.This research combines with the time series data and cross section data of 2008,is base on the existing related research methods and empirical analysis.The research methods include regional Gini coefficient,geographic concentration and the geographic distribution measurement method.The research shows that new and high tech industries highly concentrated in the coastal provinces，together with Shaanxi and Sichuan provinces,the provincial gap is wide.The share of new and high tech industries output value is significantly associated with economic development.Time series analysis shows that the concentration of industry continued to improve for a long time scale,while the tendency tended to be stable in recent years.The geographical pattern is clear gradually and the core provinces are highlighted.Due to the different nature,development foundation,resources demand and market group,different industries has different centralized situation and development trend

In order to explore the key environmental factors affecting phytoplankton community characteristics in spring and autumn in the Dongting Lake, a systematic survey of water environmental parameters and phytoplankton was conducted at 30 sampling sites of the Dongting Lake in April and October of 2018. The results showed a total of 157 species of phytoplankton belonging to 7 phyla and 51 genera were identified, and species number in April (105 species) and October (120 species) accounted for 66.9% and 76.4% of the total, respectively. The dominant groups in two surveys were all Bacillariophyta, Chlorophyta and Cyanophyta. Besides, community structure gradually changed from Bacillariophyta-dominated type to Bacillariophyta-Chlorophyta-dominated type from April to October. The average densities of phytoplankton in April and October were 19.0×104 cells/L and 18.7×104 cells/L, respectively, which indicated that abundance in two seasons did not vary significantly. The average biomass increased from 0.67 mg/L in April to 0.83 mg/L in October. Comparing the Shannon-Wiener diversity (H), Marglef diversity (d), Pielou evenness index (J) and Beta diversity in two seasons, it was found that the difference of phytoplankton community among sampling areas of the Dongting Lake in spring was larger than that in autumn, while biodiversity and richness were lower than those in autumn. The redundancy analysis (RDA) showed that pH, water velocity, conductivity and transparency were the key environmental factors affecting the phytoplankton community characteristics in April. Ammonium, water temperature, transparency and total nitrogen were the key environmental factors affecting the phytoplankton community characteristics in October. Based on previous studies in the river-connected and isolated lakes, it was found that the biodiversity of the isolated lakes were far lower than river-connected lakes, while the phytoplankton abundance and biomass of the isolated lakes were significantly higher than river-connected lakes, which was ascribed to the loss of flowing water habits and the decrease of the habitat heterogeneity in isolated lakes. It’s demonstrated that hydrological and hydrodynamic conditions are the primary factors determining phytoplankton community differences among river-connected and isolated lakes, and water physico-chemical factors (i.e., transparency, suspended solids and nutrients) are the secondary influencing factors. The results of this study can provide a scientific basis for ecological conservation of the river-connected lakes such as the Dongting Lake.

Under the impact of global economic integration,the economy raised,urbanization grew rapidly and urban agglomeration relatively matured in eastern China.However,in the central and western regions,the agglutination of production factors and the development of urban agglomeration have grew slowly,and the original urban basis is poor;small cities’development and interaction is weak,and the leading role of regions is not obvious.For these reasons,this paper analyzed the current problems,then put forward the development strategies of three major urban agglomerations in central China:build up economic development axis in central region,strengthen economy of the node,construct the core area of industrial clustering and develop the traditional agriculture,and guide to the directions of modern agriculture and city agriculture.At the same time,we should focus on the urban and rural construction,protect ecological tourism zones,so as to promote economic development and regional urbanization.

The article analyzes the six national strategic development zones along the Yangtze river delta region,who are region of Yangtze river delta region of the citycluster along the Yangtze RiverinAnhui,Wuhanmetropolitanareas,PoyangLakeecologicaleconomiczone,Urban Agglomeration of Changsha,Zhuzhou and Cheng duChongqing economic zone.Based on polarized area theory, this paper proposes methods of “topdown” and “bottomup” to identificat the function of six national strategy development zones,meanwhile,the article analyzes the level of economic development,the degree of Extroversion of economic,industry and quotient of location about the third industry.Then,we put forward various function of  strategic development zones,The Yangtze delta economic region mainly undertakes to participate in international competition, innovation and the gateway functions,region of the citycluster along the Yangtze RiverinAnhui mainly undertakes functions of boosting regional service,Poyang Lake ecologicale conomic zone mainly undertakes function of ecological conservation,Wuhan metropolitanareas mainly undertakes functions of demonstration and boosting Central regions,Urban Agglomeration of  changshazhuzhouxiangtan mainly undertakes functions of regional boosting and demonstration,Cheng duChongqing economic zone mainly undertakes function s of ecological conservationin west  and western boosting

Realizing the transition from factor-driven to innovation-driven is the key to my country’s sustainable and healthy development.China is already in a critical period of economic and industrial restructuring.Speeding up green technological innovation and industrial upgrading is an objective requirement for my country to transform from a manufacturing country to a manufacturing powerhouse and to achieve a rise in the industrial chain.In the current industrial upgrading and green development, it is necessary and practical to discover the role of green technological innovation and the degree of marketization in the process of industrial upgrading and evolution from agglomeration of innovative elements.Based on this, this article uses panel data from my country’s 31 provinces, autonomous regions, and municipalities from 2000 to 2019 to construct an evaluation index system for innovation factors, green technology innovation capabilities, and marketization levels, and comprehensive evaluation based on the entropy TOPSIS method.Use the mediation effect and moderation effect model test to explore the mediation effect of green technology innovation and the moderation effect of the degree of marketization in the process of the impact of the agglomeration of innovative elements on industrial upgrading.Concluded as follow: (1) Agglomeration of innovative elements can positively promote industrial upgrading. (2) The agglomeration of innovative elements can promote industrial upgrading by improving green technological innovation, and the ability of green technological innovation has a complete intermediary effect.(3) In the influence of the concentration of innovative elements on green technological innovation, the degree of marketization has a positive regulatory effect.Therefore, the government should promote the construction of factor markets, give full play to the decisive role of the market in resource allocation, and promote the formation of green technological innovation capabilities.

Abstract：Impervious surface is one of the key factors impacting regional spatial planning and ecological development, thus effectively indicative of change in urban development. As the central city of Huaihai economic zone, Xuzhou has been shifting its focus from rapid urbanization to ecologicalization; there, therefore, are broad implications for characterizing the dynamics of its urban impervious surface. In this study, we first identified the best impervious surface extraction approach by comparing four different impervious surface indices, namely ISA (Imperious Surface Area Index), BUAI (Built-up Area Index), BCI (Biophysical Composition Index), and ENDISI (Enhanced Normalized Difference Impervious Surface Index). By combining the fractal theory and a landscape ecology approach, we then analyzed the spatial-temporal heterogeneity of impervious surface of Xuzhou urban area (consisting of eight districts) from 2000 to 2007 and to 2017, from the perspectives of administrative division, profile lines, and landscape pattern indices, in order to characterize the dynamics of impervious surface in the context of urbanization, and provide suggestions for the future development of Xuzhou city. Results show that (1) BUAI can map impervious surface effectively and its resultant accuracy (Kappa coefficient=0.81) was by higher than the other three indices; that (2) while each district varied in impervious surface area with the Old City district (mainly for business and financial purposes) and Jinshanqiao district (the economic and technological development zone) having the highest proportions of impervious surface, growing impervious surface has been observed in the east and southeaster parts of the study area according to our BUAI based profile line analysis; and that (3) the impervious surface landscape pattern of the study area tends to be fragmented (from filled growth to dispersed expansion), complex, and irregular, suggesting its increased overall heterogeneity. Our study can provide a scientific basis for the urban development planning and land use planning.

The study about rules of cities’ spatial structure is a central research always for city planner and geographer.In the study field,W.Christaller's central place theory and A.Loesch's networks structure theory was highly valued in an early stage.Now the research hotspots is the fractal theory based on the development of human spatial behavior's selforganization.In 2001,the famous chinese's geoscientist academician.YE Danian advance the views about the city symmetry in chinese,and sort out it to a theory subsequently.With the development of chengduchongqing economic zone(CCEZ),space constructing of Sichuan cities are faced with an important chance.This paper analyzes the Sichuan cities distribution according to the city symmetry theory by YE Danian.We consider the cities distribution in Sichuan have the symmetry remarkably under the physiogeographical(just as geological structure)pattern's influence and the cities's distribution in westbasin plane show lattice character because of water natural system and land traffic trunk lines.Countered the spatial structure's deficiency of Sichuan cities,paper merge anew that spatial distribution of Sichuan cities and put forward the new theory about urban spatial structure of Sichuan which is diamond model(DM).The model can provide a satisfactory explanation for the spatial distribution and evolution trend of Sichuan cities.And point out that the city symmetry theory have theoretical and pratical values to a certain degree,so it is worth to be better studied by scholars

The evaluations of accessibility generally include network analysis,grid analysis and raster analysis.With the spatial analysis function of ArcGIS,by the method of grid analysis,to regard the 65 administrative center of counties or cities in Jiangsu Province as the nodes,under the help of traffic network data of Jiangsu Province in the year of 1990,1996,2002 and 2008,the paper analyzed the accessibility of Jiangsu Province for four study years and discussed the influencing factors of the evolution of spatial structure.The conclusions show:①The accessibility of Jiangsu Province has been significantly improved.The average value of accessibility improves up to 428%.②The accessibility has improved quite different among northJiangsu,middleJiangsu and southJiangsu.The accessibility of southJangsu is improved better than northJangsu. Throughout the study period,the accessibility of middleJangsu is improved behind the southernJangsu and northern Jangsu.③Overall,the regional average accessibility was gradually moving towards to balance,and the traffic structure of Jiangsu Province was going to consummate step by step.④By analyzing the correlation between the construction of highway network and the accessibility,the conclusion can be put forward that the effect of traffic construction is applicable to the principle of diminishing marginal utility.Increase traffic investment in backward areas contributes to the achievement of the regional benefit.⑤The accessibility evolution in Jiangsu Province reflects the demand for urban development

To systematically understand phytoplankton community structures and the corresponding impact factors, an investigation was carried out at 71 sites in the mainstream, eight primary tributaries, the Dongting Lake, and the Poyang Lake in the Yangtze River basin. The characteristics of the phytoplankton community structures were compared among different water areas and periods. The impact factors contributing to the differences of phytoplankton community structures were further explored. Results revealed that the abundance and biomass of phytoplankton in the Yangtze River basin ranged from 0.07×104 to 2 493.69×104 cells/L, and from 0.001 1 to 21.072 2 mg/L, respectively. Bacillariophyta, Chlorophyta, and Cyanophyta were the dominant phytoplankton phyla. From west to east of the Yangtze River basin, the total abundance and biomass of phytoplankton and proportion of Cyanophyta and Chlorophyta showed an increasing trend, while the proportion of Bacillariophyta abundance decreased gradually. The average total abundance and biomass of phytoplankton in the fish fattening period were higher than those in the fish breeding period and the overwintering period, characterized by higher proportion of Cyanophyta and Chlorophyta and lower proportion of Bacillariophyta. Moreover, the results of redundancy analysis, hierarchical partitioning, and variation partitioning indicated that both environmental and spatial variables contributed to the variance of phytoplankton community structures in the Yangtze River basin. In the fish fattening period, the environmental filtering effects were dominant, of which the water temperature was the most important factor and was strongly positively correlated with the total and dominant phyla abundance of phytoplankton. In the fish overwintering period, the differences in the phytoplankton community structure were better explained by spatial factors rather than the environmental factors, of which the spatial factor of MEM3 was the main factor. This study provided important data for the management of the aquatic ecology in the Yangtze River basin.

It is China's realistically choice to develop nuclear power, which is one of the practical approaches to carbon emission reduction. This paper compares the situations of nuclear power development and technology as well as resources both in the world and in China. The results indicate that there still has a long way to go for China's nuclear power industry not only in the total installed capacity but in the share of nuclear electricity, even the country has began to develop its nuclear power industry since 1970s. In reference to technique, all the generators of both in operation and under construction in China belong to the second generation technique, namely pressure water reactor. In the meantime, all the nuclear power stations in China are located in east coastal area, where the economy is thriving while energy is scarce. More importantly, China has a poor image in uranium resource, and to improve the country's resource supply in the future will rely on both the domestic and the international markets.

Abstract：The frequent occurrence of extreme heat wave events caused by global warming and rapid urbanization has affected human production and life.This paper using multi-source satellite remote sensing data and social economic statistical data, based on "high temperature risk, socio-economic vulnerability and risk adaptability" heat wave risk assessment system, to obtain the risk assessment results of typical heat wave events in the middle-lower Yangtze River in 2017.The results showed that the high-risk areas of heat wave grade were mainly distributed in the central cities of urban agglomerations and other urban central areas, mainly due to the joint effect of high urban heat temperature and social economic vulnerability.Around the central urban area, the risk level gradually decreases.Although the big cities had better adaptability to high temperature, they were far from coping with the high-temperature risk and vulnerability caused by urbanization.From the perspective of high-risk area, the heat wave risk of the Yangtze River Delta urban agglomeration was higher than the middle reaches of the Yangtze River, which was mainly related to the level of urbanization and the degree of population aggregation.Through Multi-source satellite remote sensing information data to obtain high-resolution spatial distribution information characteristics of heat wave risk in urban agglomerations, which can provide scientific reference for cities to effectively cope with high-temperature risk and strengthen regional disaster prevention and mitigation in the process of urbanization.

Currently,it is the best time to develope the Yangtze River Estuary.With the conduct of the Yangtze Estuary Deepwater Channel Regulation Project and the Yangtze Estuary passage across the river being opened to traffic,the time is ripe for us to build superdeep water berths and superdeep water channel.If we build a manmade island on the base of deepwater channel of 15m at the Outer Zone of the Yangtze Estuary,deepwater channel of 20m would be reached and deepwater Grand Port could be built which would become the bridgehead of landandsea coordinated transport in the Yangtze River Basin.Correspondently,large amount of sediment created by the Yangtze Estuary Deepwater Channel Regulation Project will create favorable conditions for accelerating the Hengsha eastern tidal flat and its surrounding sandbars into land.By the trinity of dredging,accelerative silting and the land reclamation,it is estimated to form the island groups over 500 square kilometers and shape the subdelta system between the South Port and the North Port in the Yangtze River Estuary,and on both sides of the main channel in the north channel in the next 20 years

The development of a household’s livelihood in rural areas is challenged by multiple risks. In order to stabilize the achievement of poverty alleviation and to promote rural revitalization, it is of great practical importance for rural households to build livelihood resilience to internal and external risks. Based on the resilience assessment framework proposed by Food and Agriculture Organization (FAO), this study developed an evaluation index system for measuring livelihood resilience of rural households from five dimensions, including livelihood assets, agricultural exchange and learning, adaptive capacity, social safety nets and access to basic services. Using household surveydata collected from 302 rural households in Qiliping Township, Dabie Mountain area, Hubei Province, this study examines the factors influencing livelihood resilience of rural household and evaluatesits environmental effects usingstatistical analysis and econometric models. The results show that: (1) the livelihood resilience of rural households in the study area is at a medium to high level in general. There is a clear symbiotic relationship between the livelihood resilience of rural households andthe five dimensions measuring it, presenting a gradient and gradual growth trend, among which the adaptive capacity is the weakest aspect of maintaining livelihood resilience. (2) There are a number of factors affecting the livelihood resilience of rural households, including health status, number of labour force, information access channels, involvement in local organizations or associations, the relationship between villagers and farmers, participation in collective affairs, satisfaction with village cadres and the operation of the rules and regulations in a village. (3) Rural households face a variety of negative environmental externalities attributable to their livelihood activities, and this amount increases as their livelihood resilience increases. Consequently, in order to effectively promote the sustainable development of rural livelihoods as well as the local ecological environment, it is necessary to enhance the adaptability of rural households, enhance their livelihood resilience, and minimize the negative impacts of their livelihood activities on the environment.

In recent years, composite pollution caused by particulate pollution and photochemical pollution has become an important pollution problem in large urban agglomerations. Based on the air quality monitoring data of 26 cities in the Yangtze River Delta Urban Agglomeration (YRDUA) in 2017, we analyzed the time series characteristics and pollution status of O ₃ and PM _2.5 in the region using mathematical statistics method. Then the grid data of O ₃，PM _2.5 was generated by inverse distance weight model to analyze the spatial distribution pattern of O ₃ and PM _2.5 in the region. Finally, combined with the meteorological factors of ECMWF in the same period, we discussed the effect of meteorological conditions on the concentration of O ₃ and the thresholds for the formation of high O ₃ concentration. The results show that: (1) The O ₃ concentration in YRDUA is highest in May and September, and the daily variation of O ₃_8 h is characterized by a tensile S curve, which reaches the peak concentration at 19:00 and 20:00. The maximum peak concentration is 111 μg/m ³ in Chuzhou; The spatial distribution of O ₃ gradually decreased from north to south, and spring(136.57 μg/m ³)> summer(117.35 μg/m ³)> autumn(83.23 μg/m ³)> winter(77.06 μg/m ³); O ₃ is significantly correlated with its precursors CO and NO₂. When 15<T≤20℃, 100<PRS≤100.5 kpa, O ₃ pollution is the most serious. (2) Monthly variation of PM _2.5 concentration is irregularly U-shaped distribution, the trough period is in July and August, the daily variation is double-peak trend, the first peak in Shanghai, Zhejiang region occurs at 9:00 or 10:00, in Anhui, Jiangsu region occurs at 11:00 or 12:00, the second peak is at 21:00; PM _2.5 concentrations higher in inland cities than in coastal cities, Winter(62.21 μg/m³)> Spring(44.70 μg/m³)≈ Autumn(44.14 μg/m³)> Summer (31.33 μg/m³); Compared with NO   and SO₂, PM_2.5 and CO are more relevant; O3 is positively correlated with temperature and relative humidity, negatively correlated with wind speed, wind direction, air pressure, boundary layer height, and precipitation, PM_2.5 is positively correlated with wind direction and air pressure, and negatively correlated with other factors; The temperature is less than 5℃, 100<PRS≤100.5 kpa, PM_2.5 exceeding standard rate is highest in YRDUA.

Along with the highly speedy development of economic and society in the developed area in China,with the quantity of pollution emission such as agricultural fertilizers,industrial wastewater and domestic sewage sharp increasing,the water environment has been deteriorated continuously and become a limiting factor to regional development.For harmonizing the relationship between economic development and water environment,many countries attempted to study the water environmental function zoning so as to provide a scientific basis for the basin management,but these researches ignored the spatial relation between water and land,even the index system only concluded the environmental genes but not threatening genes by human activity.This paper discussed the methods of constraint regionalization of water environment based on the capacity and pressure of water environment,including how to divide the assessed units,choose and manage the assessed elements.Then,as a case study,Wuxi City was divided into four types by the method of matrix analysis,such as highpressure and highcapacity area,highpressure and lowcapacity area,lowpressure and highcapacity area and lowpressure and lowcapacity area.Finally,this paper presented the schemes of industrial admittance and the policy of industrial development direction respectively,which was a very important base for harmonizing the industrial development and the bearing capacity of water environment

Based on the data of the 5th and 6th censuses, factor and cluster analysis and other methods were used to study the evolution trend of social spatial structure in the central city of Chengdu from 2000 to 2010. It is found that the main factors, social areas and structural patterns of urban social spatial structure in Chengdu have changed significantly in the past 10 years. The evolution characteristics of the main factors can be summarized as follows: the factors of general wage earners, professional and technical personnel and industrial workers show great changes; while the factors of immigrants and living conditions, highly educated population and minority population show certain stability and sustainability. The evolution characteristics of social areas can be summarized as the optimization of spatial structure and upgrading of function orientation in the old urban areas, and the evolution towards “three descent and two mention”; the expansion of intellectuals’ residential areas and the separation from minority agglomeration areas, showing a trend of residential differentiation; the gradual migration of foreign population to secondary and tertiary industries and the expansion of agglomeration areas; and the agglomeration districts of agricultural population gradually become suburbanized and the prominence of blue-collar population areas. The pattern of social spatial structure has evolved from the single and homogeneous “circle + fan” structure in 2000 to the “circle + fan + multi-core + multi-group” pattern in 2010. Various types of spatial regions have expanded and the spatial heterogeneity has become clearer.

Under the background that urban heat island affects urban thermal comfort, blue-green space has become an important way to effectively mitigate urban heat island effect. Selecting 18 river riparian buffer in Shanghai, the marginal effect of various indices of waterfront green spaces on the distribution of LST was quantitatively analyzed by the boosted regression tree(BRT) model. The results showed that: the cooling island effect of green spaces was the strongest in the urban periphery, followed by the suburb, and the worst was in the central area. In the aspect of spatial morphological factors of green spaces, the index of Fv and area were the dominant impacting factors on the LST. The marginal effect threshold of Fv, area, landscape shape index and albedo were 0.3, 50 hm², 2 and 0.16, respectively. In the aspect of spatial structure factors among blue spaces and green spaces, the influence of the index of water surface ratio and the distance to riverbank were larger on the LST. The higher water surface ratio is, the more obvious the cooling island effect is. The marginal effect threshold of the distance to riverbank and cohesion value were 400 m and 75/100, respectively. The study can provide useful guidance for the development of blue-green space coping with global climate change.

Major function oriented zoning (MFOZ) is one of the effective ways to coordinate current rapid economic development and resources and environmental protection in China.Therefore,we set up an integrated indicator system of MFOZ in Yixing of Jiangsu Province, an area with intensive urbanization in the Yangtze River Delta of China.The indicators' weights were determined by principal component analysis (PCA).And then, the projection values of resources and environmental restriction,present development intensity and future development potential in Yixing were calculated by grey relation projection model (GRPM) and classified as three grades (high,medium and low),respectively.According to each town's combination of resources and environment,development intensity and development potential,Yixing was divided into five main function oriented zones by three dimension magic cube classification method (TDMCCM),which consisted of optimized and integrated zone,emphasized development zone,moderately development zone,agriculture and forestry development zone and ecological protection zone.The zoning result prominently indicates the “major function” characteristics of major function oriented zone,which gradually changes from protection type to development type.Moreover,the projection value of evaluation sample calculated by GRPM is the product of the sample module and the angle cosine between evaluation sample and ideal sample. It makes the evaluation results more comprehensive and accurate

In recent years,nationwide highspeed rail network construction has been becoming the focus of public concern.Highspeed rail is extremely popular with its obvious advantages:fast speed,large transmission capacity,good security,comfort and convenience,less energy consumption,good economic returns,etc.With the building of “four vertical and four horizontal” passenger special line in full swing,our country will step into the highspeed rail age.Highspeed rail shortens the travel time and distance of people,goods and information flow.And highspeed rail opens an era of economic circle.Therefore,the approach of the highspeed rail era is bound to have a farreaching influence and significance to the region.Highspeed rail will accelerate and amplify city effect of the urban economic circles,and change the producer type of people,way of life;Highspeed rail will speed up regional integration and mutual winwin of central cities leading;Highspeed rail will promote upgrading of industry,for example,tourism and real estate,and promote redistribution of city planning along the line;Highspeed rail will cause recombination of 〖JP2〗“aviation,land transportation and waterway” three modern transportation means,bring about diversification of the way people travel

Both the urban master planning and the general land use planning are major domestic spatial planning.With the promotion of urbanization and the expansion of construction land,contradictions and conflicts between this two planning is severe.Regionalization of regional potential development alleviates the conflicts of this two planning and greatly increases the linkages,also provides the coordinative paths.Taking Wuxi for example,this paper uses regionalization of regional potential development to evaluate the two planning schemes.The analysis indicates:buildingland of the urban master planning grows fast in ecological sensitive area,while grows slowly in feasible development area;buildingland of the general land use planning doesn’t meet the need of future development and constrain actual expansion of land use,which is not according with the reality. 

Regional development is an important theoretical and practical issue in the process of urbanization and industrialization.The assessment of development situation is the premise and basis of further study of regional development.Based on regional sustainable development theory,and the dialectical relationship between regional development level and development costs,we choose the 40 cities which are along the Yangtze River as the basic evaluation unit,select the most important indicators to identify development level and costs,and construct the composite index system based on“economy-societyresourcesenvironment”.We calculate the economic and social development level of the cities,and also the resources and environment costs.According to the twodimensional matrix,we divide the cities into four zones:zone of highdevelopment level and highdevelopment cost,zone of lowdevelopment level but highdevelopment cost,zone of lowdevelopment level but highdevelopment cost,and zone of lowdevelopment level and lowdevelopment cost.From the industrial development,ecological protection,and regional coordination,we propose the corresponding policies and measures for different types of zones,to provide the foundation for a new round development of regions along the Yangtze River

County-scale eco-efficiency has been recognized as one of the important base unit that supports regional green development. Taking the urban agglomeration in the middle reaches of Yangtze River as the study area, this paper constructed the input-output index system of eco-efficiency based on multi-source data, used the Super-EBM model to measure the county eco-efficiency from 2005 to 2018, and analyzed the dynamic characteristics of its spatial pattern with the help of LISA time path and LISA temporal and spatial transition methods. The spatiotemporal transition types were nested with the panel quantile regression model to explore the driving mechanism. The results showed that the overall level of county-scale eco-efficiency of the urban agglomeration in the Middle Reaches of the Yangtze River increased significantly during 2005 to 2018. The agglomeration development effect of the three provincial capitals as the center was significant. Urban agglomeration in the middle reach of county-scale eco-efficiency of spatial distribution of cohesion was stronger and had a higher path lock feature, there was a transition in each county unit inertia, the local spatial characteristics of eco-efficiency are more dynamic in connecting county units of “Wuhan Metropolitan Circle-Changzhou-Zhuzhou-Xiangtan Urban agglomeration”, Fengcheng in space depended on the direction of maximum volatility, Changsha municipal districts had maximum stability. Four driving-restraining models, including economy-climate drive, industry-resource control, economy-resource control, and industry-precipitation control, presented an evolution pattern from “Wuhan City Circle-Poyang Lake Urban Agglomeration” to “Changzhou-Zhuzhou-Xiangtan Urban Agglomeration” from restriction to drive, each containing different driving mechanisms.

The Yangtze River Delta,one of the most developed,the most dynamic,the most densely populated and the most concentrated in industry areas of China,is growing into an influential worldclass urban agglomeration and plays an important role in China’s economic and social development.However,influenced by the climate change,the Yangtze River Delta’s urbanization and environment for construction affect each other.This paper did some researches in two aspects.On the one hand,using 2008 data it summarizes the current characteristics of urbanization in the Yangtze River Delta.The urbanization is to be further accelerated in the Yangtze River Delta.On the other hand,future climate change will led to sealevel rise.The sealevel rose to reach 220~380 mm in the next 20 years,and 270~610 mm in the next 50 years in the Yangtze River Delta.The Yangtze River Delta is bound to be affected by the process of urbanization which mainly will caused larger area of land flooded,more flood disasters,and more other environmental problems.

Abstract：Network attention reflects tourists’ overall perception of tourist destinations from the perspective of cyberspace.In this paper, we systematically analyzed the network attention and spatial pattern of Hunan tourist destination cities through the social network analysis method,using the network attention index constructed by Baidu search data of 103 keywords that are obtained by synthetically using “direct lexicon” and “’range lexicon” method. and closely related to tourist activities as analytical data.This study found that: (1)Tourists have different levels of network attention to tourist destination cities in Hunan, but the network attention of the above-mentioned tourism destination cities shows a synchronous fluctuation trend within the annual cycle which presents a strong “Collinearity”; (2)Tourists’ network attention to the tourist destination cities in Hunan constitute a relatively complete network relationship.However, the network information interaction between Yueyang and other tourist destination cities in the province is weak and there is basically no network information interaction between Loudi and Yiyang and other tourist destination cities in the province; (3)The network influence of tourists’ network attention to the tourist destination cities in Hunan shows an obvious hierarchical structure. Among them, Changsha, Chenzhou and Zhuzhou have significant advantages of “structural hole”, which in general plays an important bridging role to promote the information flow among the tourist destination cities in Hunan; (4)The spatial correlation network of tourists’ network attention to the tourism destinations in Hunan can be divided into four sections:Xiangxi is located in the “Agen” section;Four nodes, such as Hengyang, are located in the “Net overflow” position.;Six nodes including Changsha are located in the “Bidirectional overflow” position;Loudi, Yueyang and Yiyang are located in the “isolated” position; (5) It is particularly noteworthy that although tourists’ online attention to Hunan’s tourist destination cities largely reflects the resource endowment and tourism industry development of Hunan’s tourist destination cities, the two are not completely matched.Although the spatial correlation structure of tourists’ network attention to the cities in Hunan’s tourism destinations is rooted in the physical geographic space, it is quite different from the structure of physical geographic space.In view of the above findings, for the development of the tourism industry in Hunan,this paper propose that the tourist destination cities need not only to strengthen their own construction of high-quality resources and highlight their own characteristics of tourism development,but also expand the exchange and cooperation of tourism information among them.In particular, it is necessary to promote the free flow of tourist，tourism information and other elements in Hunan and gradually form a multi-center multi-network coordinated development of tourism space pattern.

The purpose of the study is to analyze the spatial variation of 〖JP2〗economy in PanYangtze River Delta.〖JP〗The economic growth in each region not only 〖JP2〗depends on its own characteristics,but also on the neighborhood〖JP〗 regions which it belongs to.Unfortunately,the traditional approaches 〖JP2〗suppose that each region is independent〖JP〗 from others,so they just evaluate the regional disparity variations of "isolated" regions and cannot tell the dynamics of interrelated regions.Methods of ESDA were employed,which 〖JP2〗could incorporate spatial〖JP〗 effects into the analysis of regional disparities,identify global and local disparities at the 〖JP2〗regional scale and visualize〖JP〗 the spatial distribution and patterns through Moran scatter plots or LISA maps.In order to avoid the variation instability of the variable of per capita GDP,methods of spatial autocorrelation indicators adjusted by Empirical Bayes was employed. This paper investigated the spatial dynamics of regional disparities at the municipal level in PanYangtze River Delta by analyzing per capita GDP data,1999~2008.The results indicated that the economy development showed obvious spatial cluster pattern in PanYangtze River Delta.The value of EBI showed a trend of increased volatility; the spatial transfer of clusters and outliers showed definite rules; the economy development showed obvious local spatial disparity pattern.The study indicated the feature of the Yangtze River Delta region with highvalue and the new expansion provinces with lowvalue

How to coordinate the relationship among economy, ecological environment and social welfare is an important task of sustainable development. This paper uses the super efficiency SBM model to measure the ecological welfare performance of the Yangtze River Economic Belt in 2007-2017, uses the barycenter model and spatial interpolation method to describe the spatial pattern evolution of the ecological welfare performance, and on this basis, uses the vector autoregressive model to analyze the dynamic response relationship between the ecological welfare performance and its influencing factors.The main conclusions are as follows: (1) from 2007 to 2017, the ecological welfare performance of the Yangtze River Economic Belt shows an upward trend in the early stage, but decreases in the later, and its overall value is low, which is mainly affected by scale efficiency.（2) On the whole, the track of the performance’s gravity center moves eastward and northward,and the high value areas are mainly concentrated in the middle reaches of the Yangtze River.From the perspective of spatial pattern, the ecological welfare performance in the middle and lower reaches of the region takes Hunan Province and Shanghai City as the high value centers respectively, which decreases from circle to circle, showing a more significant spatial structure of “core-periphery” .However, the overall performance of the upstream region is gradually lagging behind.(3) The impact of scale effect on the performance of ecological welfare is not significant in the current period. Its response value reaches the maximum value in the second period, and fluctuates near zero value in the sixth to tenth periods; the structural effect always shows negative impact, and the overall range of change is small; while the frequency of negative response of technical effect is significantly higher than that of positive.From the perspective of variance decomposition, performance is basically impacted by itself, but in the later stage, the contribution rate of its influencing factors has increase in varying degrees.

Fish passage facilities have been designed and developed to enable fish to pass the barriers for up/ downstream migration. The performance monitoring and evaluation of those facilities post the constructions are essential for the functional verifications, design improvements, and management benefits. This study reviewed the performance studies of fish passage facilities for upstream migration, from which the evaluation principles, methods for monitoring and regional technical standards were concluded. The scientific monitoring and evaluation of fish passage in North American, Australia and European was separately initialized from 1960s to 1980s, and boomed since 2000s. Both fish passage effectiveness and passage efficiency are separately used for a qualitative and quantitative evaluation of the performance of fish passage facilities. The existing monitoring methods, roughly classified as capturedependent and captureindependent, are frequently used for such performance evaluation, depending on the purpose and availabilities and limitations of given methods. Moreover, due to the variations in geographical feature of river, structure of fish passage facilities, target species considerations as well as the requirements from the regional laws and technical standards, the focus of approach and evaluation criteria varied significantly in geographic region. Currently, experts from North American frequently specialized in the passage efficiency evaluation and using the advanced captureindependent methods while experts from European frequently specialized in the effectiveness evaluation using both capturedependent and traditional captureindependent methods. Fish passage monitoring and evaluation in China began in 1970s, yet suspended between 1980s and 2000s, as results of the argumentations over mitigation options. Such studies rebooted because of the efforts of restoring fish populations with fish passage facilities from 2000s. As a consequence of construction boom of dam and fish passage facilities in China, the performances of such passage facilities will be a primary point of concern. Development of regional monitoring and evaluation criterions in China is urgently required. Those monitoring and evaluation are capable of drawing lessons from other countries. However, variations of geographical feature of river, structure of fish passage and consideration of target species must be recognized in China, comparing to those elsewhere.

Lakes provide important freshwater resource for regional development. Climate change and human activities significantly affect the spatial and temporal distribution of water resource at the global scale. Consequently, frequent floods and droughts occur in lake catchments, impacting local water security and aquatic ecosystem health. Lake catchment is a relatively independent geographic unit, and thus, has been used as an ideal area for hydrology research. Focusing on several new hydrological issues in the 21st century, this article reviewed up-to-date hydrology research status in topics including extreme hydrological events, hydrological impacts of land cover changes, integrated modelling of lake catchment, evolution and future projection of water resource availability of lake catchment. Exemplified in Poyang Lake catchment, a large freshwater lake in the middle Yangtze River, research gaps are identified and future directions are suggested. This article may enrich the research context of catchment hydrology and limnology, and may be of reference value to the future development of relevant science disciplines.

Abstract：Fractional vegetation coverage is an important index to measure vegetation growth and describe ecosystem environment. Based on the MODIS NDVI data set from 2001 to 2018, the fractional vegetation coverage in China was calculated using mixed pixel dichotomy model. Then, the spatial and temporal characteristics of annual fractional vegetation coverage in China are analyzed. To explore the response mechanism of fractional vegetation coverage to climate and human disturbance, and the future change characteristics of human disturbance to fractional vegetation coverage. The results show that: (1) fractional vegetation coverage in China is on the rise as a whole. The fractional vegetation coverage in Northwest China is significantly lower than that in Southeast China. Except the fractional vegetation coverage of the Qinghai-Tibet Plateau is declining, the others are on the rise, which has a certain sustainability. (2) Among all vegetation types, the average annual fractional vegetation coverage of mixed forest is the highest, while that of grassland is the lowest. The change rate of crop vegetation is the largest, while that of mixed forest is the smallest, and it will change from improvement to degradation in the future. The other types showed continuous improvement. (3) Fractional vegetation coverage is negatively correlated with temperature and positively correlated with precipitation in China. Moreover, precipitation has a stronger impact on fractional vegetation coverage than temperature. This indicates that precipitation is the main factor affecting the change of fractional vegetation coverage. (4) The impact of human activities on fractional vegetation coverage in China shows an increasing trend as a whole. In the future, the influence of human activities will be mainly reverse persistence. This indicates that the fractional vegetation coverage in China will be affected by human activities in the next 18 years.