Abstract：Based on the panel data from 285 prefecture-level cities or above in China during 2006 and 2016, this article adapts the dynamic panel data model with System GMM estimation method and panel threshold regression model to disclose the effect of the specialized and diversified industrial agglomeration on urban water intensity. On this basis, the stage characteristics of different industrial agglomeration types and water use intensity are tested by introducing economic development level, infrastructure construction level and employment density as the threshold variables. The results indicate that: (1) Specialized industrial agglomeration alleviates the intensity of urban water by realizing positive technology spillover. (2) Similarly, diversified industrial agglomeration reveals a saving role in the process of urban water resource utilization. (3) Under the adjusting effect of urban scale, the relationship between different industrial agglomeration types and urban water intensity shows obvious characteristics of regime switching. (4) With the continued expansion of economic scale, industrial clusters will gradually become saturated, moreover, the situation of water resources competition will intensify, and the allocation efficiency of water resources will be reduced.(5) When urban infrastructure is limited, over-agglomeration exceeds regional carrying capacity, which will lead to vicious competition for public infrastructure and make it difficult to exert the positive spillover effect on urban water resources allocation. （6） In addition, as the employment density increases further, the mechanism of path dependence of specialized industrial agglomeration may induce technology lock-in effect. However, due to the diverse knowledge base, the labor pooling effect of diversified industrial agglomeration is more obvious, meanwhile, the improvement of collaborative learning ability will promote the green technology progress and bring water-saving effect into full play.

Abstract：Research divided 30 provinces and cities in China into eight regions. Based on the 2007-2017 interprovincial logistics industry panel data, a three-stage Super-SBM model and Malmquist index model were constructed to calculate the green total factor productivity of the logistics industry. ESDA and spatial convergence models were used to analyze the spatial and temporal differences and spatial convergence. The results show that: (1) After removing the constraints of management inefficiency and external environmental factors, the national average value of GTFP decreases to 0.985. In the southern coastal, northern coastal, northwest and eastern coastal areas increases, the GTFP indexes are increasing. In the middle reaches of the Yangtze river, northeast, southwest and the middle reaches of the Yellow River, the GTFP indexes are decreasing.(2) In terms of time difference, the GTFP index is divided into three periods. The GTFP index of 2007-2012 is greater than 1, the GTFP index of 2012-2014 is less than 1, the GTFP index of 2014-2017 is greater than 1.(3) The spatial autocorrelation is gradually strengthened. The northeast, northern coastal, the middle reaches of the Yellow River, the middle reaches of the Yangtze river and southwest regions show positive spatial pull effect. Beijing, Tianjin and Shandong have always been the core drive high green total factor productivity provinces. The development of logistics industry in China is not balanced, the development of different regions varies greatly, and the phenomenon of polarization is serious.(4) The GTFP level of China’s logistics industry presents “M” type fluctuation, and tends to converge finally. Eight regions can be divided into two categories. The northern coastal, the eastern coastal, the southern coastal and the middle reaches of the Yangtze river regions tend to converge. The middle reaches of the Yellow River, northeast, southwest and northwest regions tend to diverge.

Abstract：This article aims to reveal the coupling coordination degree among economic development, spatial development and environmental evolution, and the coupling coordination degree between any two systems in the Pan-Yangtze River Delta region in 2005, 2010 and 2016. In this paper, the index system have been built embodying these three aspects, based on the coupling coordination model, the spatial-temporal pattern and the rule of coupling co-evolution of coordination degree of economic development, spatial development and environmental evolution, and the coupling coordination degree between any two systems were examined comprehensively. Main results for this study are as follows: 1) The coupling degree of economy development, space exploitation and environment evolution exhibited significant difference spatially and temporally; to be specific, it presented a spatial pattern of “high in the northeast and low in the southwest”. In the time dimension, it is in an evolutionary trend close to the “S” type. 2) The coupling coordinating degree of economy development, space exploitation and environment evolution has a certain correlation with the spatial distribution of its coupling degree, it presented a spatial pattern of “high in the middle and east, and low in the south and north”. In the time dimension, it is in an evolutionary trend close to the growth curve of the inverted “U” type. 3) There were obvious differences of coupling coordination status between any two systems, the coupling coordination of economy development and space exploitation had the poorest condition. Thus, it is the key direction to be strengthened and optimized in the future; whilst the coupling coordination between economy development and environment evolution had high coupling coordination condition; and the coupling coordination of space exploitation and environment evolution had increased faster.

Abstract：The diversified and coordinated development of rural leisure tourism destinations contributes to the optimization of spatial pattern of rural tourism. Taking Jiangxi Province as a case study, this paper selects 312 rural leisure tourism destinations as research objects and uses geographic concentration index, coefficient of variation, kernel density analysis, grid analysis, and buffer analysis to explore the types, spatial distribution patterns and influencing factors of rural leisure tourism destinations based on Arc-GIS10.2 spatial analysis tool. Conclusions are as follows: (1) various types of rural leisure tourism destination were found, mainly including the following six types: ecological and sightseeing, leisure and vacation, farming experience, agricultural science and technology, folk culture and characteristic villages and towns. (2) The overall spatial distribution pattern of rural leisure tourism destinations in Jiangxi Province shows the character of human-shape agglomeration, specifically, “nearing rivers and lakes ”, “closing to the scenic spots”, “along the main roads”, and “around the metropolis” are common characters. (3) The spatial distribution patterns of all types of rural leisure tourism destinations are agglomerated, but the agglomeration status has obvious differences among six types. The type of local culture is the most concentrated, while the agricultural science and technology shows on the least concentrated character. (4) The abundant water resource, the construction of five-A or four-A scenic spots, the accessibility of the traffic network, urban tourists source and the support of rural tourism policies have played a pivotal role in the spatial distribution of rural leisure tourism destinations in Jiangxi. Based on the research conclusions, the following four suggestions are proposed to optimize the spatial distribution pattern of rural leisure tourism destinations and the future development of rural leisure tourism in Jiangxi: (1) Fully understand the market demand and resource attributes, and promote the coordinated development of various rural leisure tourism destinations; (2) Deeply explore the advantages of red culture and Hakka culture in the central and southern areas to achieve balanced development of rural leisure tourism; (3) Promptly improve the transportation network system around Ganzhou, and enhance the accessibility of rural leisure tourism destinations in southern Jiangxi; (4) Actively promote the construction of high-star tourist attractions and reinforce their radiation effects on rural leisure tourism destinations.

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.

Abstract：Based on the land evaluation and site assessment (LESA) system, this paper constructs an index system consisting of the natural quality, ecological sensitivity, location conditions, farming conditions and soil environmental safety risks of cultivated land. Then, according to the method of Decision Tree Induction, the cultivated land is divided into six types: industrial pollution area, ecological agriculture area, rotation and fallow area, agricultural concentrated area, leisure farming area and non-agricultural risking area. Furthermore, on the foundation of each area’s management and protection focus, three ecological compensation modes are put forward, including large-scale operation and green production ecological compensation mode, agritourism and farmland conservation ecological compensation mode, and land-use regulation and development restriction ecological compensation mode. The research shows that the natural quality of farmland in Shanghai Pudong New Area is pretty well, about 50% of the arable land can be produced in a large scale, and nearly 90% of the arable land can ensure agricultural production. However, over 10% of the arable land still faces great risks of industrial pollution and non-agricultural transformation. It is suggested to apply large-scale operation and green production ecological compensation mode in the areas of agricultural concentrated area and ecological agriculture area, which aim at stable production, high yield and ecological coordination. To adopt agritourism and farmland conservation ecological compensation mode in the areas of rotation and fallow area and leisure farming area, which try to explore new forms of agricultural production activities. To implement land-use regulation and development restriction ecological compensation mode in the areas of industrial pollution area and non-agricultural risking area, which have higher land conversion tendency.

Abstract：The disorderly expansion of urban land leads to the decline of ecosystem service function, which affects the coordinated development of society, economy and ecology. Based on DMSP/OLS data, Landsat TM/OLS data, this paper analyzed the spatio-temporal characteristics of urban expansion. Meanwhile, based on MODIS NDVI data, crop yield data, land use data, meteorological data and soil type data, the spatial distribution and changes of food supply, NPP and runoff depth in 2005 and 2015 were simulated using food supply, model CASA model and SCS_CN model. Finally, through correlation analysis and normalization analysis, the changes of ecosystem services and trade-off or synergy are explained in different urbanization categories, discussed the problems and challenges in process of urban expansion, and gives some ideas for future urban development. The basic conclusions are as follows: ①The Chongqing city was separated into three urbanization categories (developing urban, developed urban, and rural areas). In terms of time, urban land has expanded dramatically, from 2005 to 2015 increased by 373.9 km, the urban land expansion was the smallest because of urban land distribution in developed areas was relatively saturated, development urban was the largest. In terms of space, urban land extends along the northeast and southwest directions, Yubei District and jiangbei District in the east-northeast direction were affected by the “liangjiang new area”, and the increment of urban land was the largest; ②In 2005 and 2015, the service functions of food supply, carbon sequestration and soil water storage were the lowest in developed urban areas, followed by development urban areas, and the highest in rural areas. In addition, the ecosystem service functions have showed tendency of significant decline, the largest decline area was development urban, which coincided spatially with the area with the greatest urban expansion, it showed that the change of land use type caused by urban expansion was an important reason for the decline of ecosystem service function; ③The trade-off and synergy between ecosystem services were affected by the degree of urban development; ④ Urban expansion has significant impacts on ecosystem services, the areas with biggest decline of ecosystem service was developing urban, and food supply was the most obvious service function of the recession. It was found that the rapid expansion of urban land destroys the ecosystem services, reduces the environmental capacity and affects the comfort of residence of citizens. In view of this, some ideas for the development of urban expansion are given at the end of this paper. The research results of this paper provide a scientific basis for analyzing the causes of the problems in the urbanization process, seeking the coordinated development, and Rational planning and development in Chongqing City.

Abstract：With the rising status of water resources in the social and economic development, Strengthening integrated water resources management is an important way to achieve sustainable use of water resources for countries in the world. There are many disputes in the preparation of water resources balance sheet, such as basic form, related indicators and accounting methods. Physical accounting is the basis for the preparation of water resources balance sheet, and value accounting is its goal. The method of water resources value accounting is the key and difficulty in the preparation of water resources balance sheet, which has always restricted the identification of water resources value and the feasibility and accuracy of its integration into System of National Accounts. In accordance with the basic accounting principle of water resources balance sheet and the compiling ideas of “water resources assets-water resources liabilities=net assets of water resources”, water resources balance sheet which reflects the excessive consumption of water resources, water environmental damage, and occupation of ecological water caused by social-economic use of water was put forward in this paper. Based on the compilation of physical quantity account, according to the hydrological cycle and characteristics of water resources, multi-purpose water resources were converted into emergy of the same standard for quantitative value research by emergy analysis method, so as to improve or make up for the deficiency of judgment standard differences in water resources value accounting methods to a certain extent. An attempt was made to realize the unified accounting of water quantity and water quality in a table, and to clarify the relations of obligatory right and debt on water resources value between environment and economy from three aspects of water resource, water environment and water ecology. The results show that there are no liabilities for water resources consumption reduction in Chengdu in 2015, but there are liabilities of 152 million Yuan for water environmental damage and 115 million Yuan for water ecological squeezing, which provide a basis for paid use of water resources and water ecological protection, as well as new ideas and methods for the real realization of the balance sheet of water resources value.

Abstract：Strategic emerging industries have become the driving force for economic growth with the background of New Normal of China’s economy, while rare light metals have provided core competitiveness for improving the international status and level of strategic emerging industries. In this paper, we learn from the European Union criticality methodology to assess criticality of lithium and beryllium between 2009 and 2016 from three assessment components：supply risk, environment risk and economic risk. The results show that: （1)Lithium presents a relatively low level in the supply risk, a high risk level in the environmental risk, and a higher level in the economic risk with drastic fluctuation during the period 2013-2015, having a high risk.(2）Compared with lithium, beryllium is at a higher risk level in the three risk dimensions. In general, the critical assessment results of lithium and beryllium have reached the critical benchmark value, and we should pay adequate attention to the construction of dynamic criticality assessment mechanism.

Abstract：How the structure and the associated impacting factors of benthic organisms responding to ecological remediation project is a promising work of ecosystem manipulation for wetlands remediation. The annual temporal and spatial patterns of benthic community structure were studied in Scirpus mariqueter wetland on remediated Nanhui Coasts. A total of 30 species of macro benthos were identified in the study. The dominant species appeared in the whole four seasons are Stenothyra glabra, Assiminea, Assimineaviolacea, and Glauconomechinensis Gray. In spring, Glauconomechinensis Gray is the dominant species, and the dominance value is bigger than 0.4. In summer, Assimineasp and Assimineaviolacea Heude are the dominant species with the dominance value bigger 0.1 and 0.2 respectively. By a number of 13 in autumn and winter the dominant species number is higher than that in spring and summer but the dominance value is lower than that in spring and summer, and distributes spatial evenly. There is significant spatial difference for the indices of Shannon-Weiner Index (H’）, species richness (p<0.01) and Pilou’s evenness index (p<0.05), with a highest H’ value of 2.53. According to the Specification for Offshore Environmental Monitoring (HJ442-2008) the habitat quality of Nanhui Coasts are upgraded from very poor and poor levels to general. The canonical correlation analysis (CCA) showed that in spring, summer and autumn the benthic organisms are significantly correlated with vegetation index and elevation, followed by organic carbon and water content, conductivity, and NO-3,while in winter the affecting factor is water content, electrical conductivity and NO-3.

Abstract：In the large high-productive river basin, periphytic algae are the base of the food web for many organisms in the natural ecosystem, and now have been played an important role in monitoring the water quality and assessing the health of aquatic ecosystem in order to manage the river watershed. In the present study, the structure of periphytic algae community and its relationship with water environmental factors were explored throughout the Ganjiang River basin, the largest river in Jiangxi. Fifty-three sampling sites were chosen for the investigation of the periphytic algae community in Ganjiang River during the high water period. Results showed that a total of 175 periphytic algaespecies were identified in Ganjiang River, belonging to 42 genera of 3 phyla. There were 151 species of Bacillariophyta, 12 species of Chlorophyta and 12 species of Cyanophyta in the river, respectively. Navicula was the dominant genus in Ganjiang River basin, occupied 14.080% of periphytic algae genera density. Cymbella and Navicula were the dominant genus in the downstream of Ganjiang River basin, occupied 13.088% and 12.935% of the genera density, respectively. Cymbella was the dominant genus in the midstream, occupied 12.849% of the genera density. Gomphonema was the dominant genus in the upstream, occupied 10.150% of the genera density. The Monte Carlo significance test results showed that the periphytic algae in downstream was significance affected by total nitrogen (TN), dissolved oxygen (DO), Chlorophyll a and conductivity. The periphytic algae in r midstream was significance affected by altitude, velocity, river width, and total phosphorus (TP). The periphytic algae in upstream was significance affected by TN, river width, turbidity and velocity. Redundancy analysis (RDA) was applied to reveal the relationship between periphytic algae community and water environmental factors. Results showed that Chlorophyll a and conductivity were the main factors for periphytic algae communities in the downstream. Altitude and TN were the main factors for periphytic algae communities in the midstream and upstream, respectively. It could be suggested that the water quality was reflected by the community structure of periphytic algae to some extent in the downstream and upstream, but not for the midstream. 

Abstract：It has been reported that community structure of crustacean zooplankton have been used as an indicator of trophic status. Many researches focused on inland natural waters, such as lakes and reservoirs. Differ in densities and macrophytes, the culture models and water environments were different in Trionyx sinensis cultured-pond. In the study, physical-chemical parameters and crustacean composition of four T.sinensis pond-cultured models were investigated from July to October and their correlation with trophic status was analyzed. The results showed that the DO, NH₄⁺-N, NO₂^--N, TN, TP, COD, Chl a and TLI of T. sinensis monoculture model were significantly higher than those of T.sinensis-Nelumbo nucifera, T.sinensis-ecology and T.sinensis-Trapa acornis model, while the SD of T.sinensis monoculture model were significantly lower than those of T.sinensis-Nelumbo nucifera, T.sinensis-ecology and T. sinensis-Trapa acornis model (P<0.05). A total of 7 species to 6 genus of cladoceran, 3 species to 3 genus of calanoid and 6 species to 6 genus of cyclopoid were recorded in all four models. Their conjoint dominant species were Paracyclops fimbriatus, Mesocyclops leuckarti and Thermocyclops taihokuensis. Cluster analysis showed that the T.sinensis monoculture model was divided into one group, and the T.sinensis-lotus model, T.sinensis-N. nucifera and T.sinensis- ecological model were grouped into one group. The abundance of cladocera was shown to be negatively related to TLI (P>0.05), the abundance of calanoid was positively related to TLI (P>0.05), and there was a significant positively correlation between the abundance of cyclopoid and crustacean and TLI (P<0.05); RDA showed that Chl a, NO₂^--N, SD, WT and COD significantly affected the composition of zooplankton crustacean (P<0.05). Our findings can not only provide technical guidance for the development of pond culture model of Chinese soft-shelled turtle, but also provide theoretical support for the study of fishery production affecting the structure and function of freshwater ecosystem.

Abstract：The study of spatial characteristics of groundwater level is important for rational development and effective utilization of groundwater resources. In order to eliminate the influence of human factors, 118 schemes are constructed with separation distance increment and its corresponding allowable range of variation, maximum calculation range and variance model structure as variables. The parameters of variance model and the statistical results of cross-validation of different schemes are compared and analyzed by cross-validation method and its evaluation index. On this basis, the relatively optimal variogram model is screened out. The numerical model is used to study the spatial distribution characteristics of groundwater level around the East Lake. The results show that: (1) Variogram model parameters and their cross-validation results of different structures are quite different with each other. Variogram model parameters and their corresponding cross-validation resluts of the same structure also have obvious change trend with separation distance increment and the maximum calculation range, and some cross-validation results have opposite effects; (2) The variogram model of groundwater level in Dongting Lake area is a spherical model with parameters: a=97.8 km, C0=9.86 and C1=45.36. The nugget coefficient is 17.9%, which indicates that the groundwater level in the study area has a strong spatial correlation, and structural factors play a leading role in spatial variability; (3) The groundwater level in the area around Dongting Lake generally presents a circular distribution, which decreases in turn from outward to inland, and the groundwater depth decreases in turn. The groundwater level in the study area is closely related to the topography and river system structure.

Abstract：In order to understand assemblage structure characteristics of hygrophytes and their driving factors in the Yangtze mainstem, we carried out field investigations of hygrophytes in five sand bars in Yichang-Jianli section during March-May 2018. A total of 88 species of hygrophytes, belonging to 26 families, 73 genera were collected. Among them, Compositae, Gramineae, Polygonaceae were dominant，Cynodon dactylon、Carex leiorhyncha、Hemarthria altissima、Phalaris arundinacea were the predominant species. The average species number in plots was 6, the average density was 89 ind/m² and average biomass (above ground part, dry mass) 55.8 g/m². Assemblage structure characteristics of hygrophytes varied in space and time. Plot species number, density and biomass in the Zhicheng section were the largest, while those in Jingzhou section were the smallest. Density of hygrophytes decreased from March to May, while biomass increased. Ten dominant assemblages were identified including Carex leiorhyncha, Cynodon dactylon, Hemarthria altissima-Aster tataricus and the others. Canonical correspondence analysis indicated hygrophytic plant assemblages were mainly affected by clay proportion (Clay), elevation above water (ELEV), soil moisture (SM)and total organic matter content in soil (TOM), and the most important one was Clay. Moreover, plot total biomass changed with ELEV, SM and TOM in a similar way, i.e. it increased first and then decreased along these factors. The relationship between plot biomass and Clay was insignificant. We concluded that hygrophytic assemblages in sand bars were driven by hydrological regimes under which substrate, soil moisture and nutrients acted together to shape the assemblages. 

Abstract：Seedling functional traits reflect plant life history strategy and may potentially influence forest regeneration and species coexistence in forest communities. Based on 25 hm2 Badagongshan (BDGS) forest plot in Hunan province, we selected 24 common tree species and collected functional traits of 826 seedlings. Variations of seedling functional traits and their effects on seedling survival were analyzed. The main results are as following: (1) Some significant trait trends were detected among different seedling height. Specific leaf area (SLA) and carbon-nitrogen ratio (C/N) decreased while stem specific density (SSD), petiole length (PL), nitrogen-phosphorus ratio (N/P) and chlorophyll (Chl) increased with the growth of seedling. (2) No significance of SLA and remarkable differences of leaf thickness (LT), Chl and N/P were detected between canopy, understory and shrub. SSD and PL showed no difference between canopy and shrub while C/N showed no difference between understory and shrub. (3) Evergreen trees had larger LT and Chl while deciduous trees had larger SLA, leaf nitrogen content (LNC), leaf phosphorus content (LPC) and PL. (4) Individual size meant a lot in seedling survival. LPC acted inversely in the survival of evergreen and deciduous seedlings. In early life stage, different plant functional groups adopted different adaptation strategies and seedlings of different sizes adjusted their traits to the light change. Moreover, there was a nitrogen limitation in seedling growth in Badagongshan (BDGS) subtropical evergreen and deciduous broad-leaved mixed forest and this limitation became weaker with the growth of seedling.

Abstract：At present, there were few researches on the influence of human activity intensity on wetland landscape pattern at large scale. To reveal the relationship between the wetland landscape pattern in the middle and lower reaches of the Yangtze River Basin and human activity intensity, the paper took the land use data of the middle and lower reaches of the Yangtze River Basin from 1995 to 2015 as data sources. Human activity intensity of land surface (HAILS), and landscape index were comprehensively used to analyze the evolution characteristics of human activity intensity, wetland landscape pattern characteristics and the influence of human activity intensity on wetland landscape pattern. The results showed that: (1) The area of high human activity intensity zone increased, while the area of low human activity intensity zone decreased; the average value of each human activity intensity zone showed an increasing trend from 1995 to 2015, and the higher of the intensity zone grade, the greater of the increasing range of average value. (2) In the past 20 years, the wetland area has been increasing, accounting for 5.14%, 5.27% and 5.30% respectively; lakes and marshes have decreased by 70.73 km² and 216.53 km² respectively, while the area of reservoir pond has increased by 1 155.32 km2, contributing 94.75% to the increase of wetland. It indicated that artificial wetlands were expanding while natural wetlands were shrinking during the study period. The fragmentation of wetland landscape was weakened, and the landscape diversity was decreased. (3) The relative change of wetlands showed a ‘contraction’ effect with the increase of human activity intensity, and the higher human activity intensity, the more obvious of the ‘contraction’ effect. With the decrease of human activity intensity, the fragmentation of wetland landscape was weakened, the aggregation reduced, the landscape diversity enhanced and the landscape shape tended to be complex. The research results can provide decision support for wetland protection and human activity control in the middle and lower reaches of the Yangtze River Basin.

Abstract：In order to reveal the variation characteristics and influencing factors of CO₂ degassing across water-air interface in karst underground river at different time scales. This study used the floating chamber- gas chromatography to monitored seasonal variation and diurnal variation of CO₂ exchange flux at the water-gas interface in Maocun, Guilin. The results were as follows: CO₂ exchange flux at the water-gas interface has obvious seasonal and diurnal variation characteristics. In addition, CO₂ is released into the atmosphere by karst underground River, which is the characteristic of atmospheric CO₂ source. On the seasonal scale, CO₂ exchange flux varies from 90.27 mg·(m²·h)^-1 to 406.32 mg·(m²·h)^-1, with an average value of 253.50 mg·(m²·h)^-1. The seasonal characteristics of CO₂ exchange flux are higher in rainy season than dry season. On the diurnal variation monitoring scale, CO₂ exchange flux varies from 46.8 mg·(m²·h)^-1 to 244.45 mg·(m²·h)^-1, with an average value of 137.81 mg·(m²·h)^-1.CO₂ exchange flux at night was significantly higher than day, the highest value appeared at 0∶00 and 1∶00 in the morning, and the lowest value appeared at 14∶00 and 15∶00 in the afternoon. The CO₂ exchange flux at the water-gas interface was affected by many factors. The correlation analysis shows that the main controlling factor of CO₂ exchange flux is the carbonate equilibrium system of Maocun underground river outlet at the seasonal scale, but the main controlling factor was the local regional environmental parameter at the diurnal scale.

Abstract：The effect of ecological planning on local climate in Guangyang Island of Chongqing City is investigated by numerical simulation of urban micro-scale model. The results show that Guangyang Island is dominated by northerlies in January, and the wind speed in west part of the island is relatively bigger. However, the island is prevailed by easterlies in July. The temperature field of the island shows a east-west contrast pattern, i.e., the east (west) part is high (low), in both January and July. The comfort analysis shows that the island is quite comfortable in January, but is not so comfortable in July because of high temperatures. The numerical simulation of ecological planning shows that the most notable effect of the planning on local climate is temperature field. The ecological planning could significantly reduce the temperature, which improves the human comfort in July.

Abstract：Regional meteorological conditions and air quality may be closely related to global climate changes. Global climate changes were categorized as El Nio and La Nia. Based on the large data mining technologies of k-nearest neighbor (KNN), historical meteorological data from 1951 to 2017 and air quality data from 2013 to 2017 of Chengdu were both used for trend analysis and its correlation with global climate changes. The K-nearest neighbor (KNN) was used to evaluate the contribution of both meteorological conditions and emissions reduction to the air quality improvement. Results showed that global climate changes have significant impacts on both regional meteorological conditions and air quality. Both El Nio and La Nia have caused regional changes of meteorological conditions such as air temperature, precipitation, wind speed, and sunshine hours. It has facilitated the diffusion and dispersion of atmospheric pollutants. As a result, the air quality has been improved locally except for tropospheric zone. Compared to years with typical meteorological conditions, higher ozone concentrations were observed under El Nio or La Nia due to a variety of reasons. For the year of 2015, A KNN model was developed using the observed meteorology factors and heave pollution days. It is found that for the reduced heave pollution days in 2015(El Nio year), 73% can be attributed to the emission reduction, and 27% was caused by the improvement of meteorological conditions. In 2016(La Nia year), 42% was caused by the improvement of meteorological conditions. Thus, policy-making regarding air quality improvement and management should take into account both meteorological conditions and emissions sources.

Abstract：Some researches have already been carried out to discuss about the effect of rural ageing labor force on land transfer. Two main reasons for this effect are believed to be land complex and labor capacity restriction, which are both caused by aging. It is significant to clarify the relationship between the two factors in order to deepen the understanding of the effect of rural ageing labor force on land transfer. Using the national baseline survey data of CLDS (2016) and the intermediary effect model, this paper empirically tests the intermediary effect of land complex and labor capacity restriction on the influence of rural ageing labor force on land transfer, and make comparison between them . The results show that land complex and labor capacity restriction both show strong mediating effect. On average, the land complex of the elderly population can explain 16.37% of the probability of land supply, 12.34% of the supply area, 6.72% of the probability of land demand and 6.43% of the demand area. The labor capacity constraints of the elderly population can explain 40.10% of the probability of farmer land supply, 36.50% of the supply area, 12.34% of the probability of farmer land demand and 14.49% of the demand area. Compared with the land complex, the mediating effect of labor capacity restriction is stronger. Its comprehensive effect is that the aging of labor force significantly increases the land supply of farmers, and also significantly inhibits the land inflow demand of farmers. Therefore, with the aggravation of aging, the problem of rural land transfer market is not insufficient supply, but insufficient demand. In order to activate the effective demand of land circulation market, it is necessary to strengthen the cultivation of new agricultural management subjects, improve the level of agricultural automation and improve the compensation mechanism of agricultural land management.

Abstract：Based on panel data of 11 cities in Jiangxi Province from 2007 to 2016 and the classic misallocation model of productive factors, this paper calculates the misallocation of agricultural factors, and analyzes the factors that influence misallocation of agricultural factors in those cities. The research result shows the overall factor misallocation is the most serious and the misallocation of capital ranks second. The misallocation of labor is the least serious. From regional distribution perspective, the difference of misallocation of agricultural factors is obvious among cities. The dispersion of misallocation of labor increases after decreasing while the dispersion of misallocation of capital and total factor decreases over time. From time perspective, three kinds of misallocation experience the process of increasing first and then decreasing. Misallocation of agricultural factors in a few cities in Jiangxi Province fluctuates greatly during the measurement period. The result of empirical research shows that the financial support, industrialization level, agricultural labor ratio and fertilizer input per capita contribute to reduce the misallocation of agricultural factors while the cultivated area per capita promotes the misallocation. Hence, the scale effect of agricultural production is not fully reflected. To increase the allocation efficiency of agricultural production factor, it is necessary to emphasize on reducing misallocation of capital and improve financial system of supporting agriculture aiming to enhance the coordination between policy and agricultural endowment. Also it is necessary to encourage productive factor to return to agricultural sector, optimize the input ratio of productive factor, sufficiently take the advantage of scale management and promote technical advance and innovation of agriculture.

Abstract：Based on the micro-survey data of 1 488 households in 47 counties (districts) of 11 cities in Jiangxi Province, the Tobit model was used to empirically analyze the impact of that years of farming and neighborhood communication on farmers' ecological farming adoption. The purpose of this paper is to provide a reference for improving the effectiveness of cultivated land ecological protection and ensuring the quality of crops in China. The results of research: (1) 43.40% of the sample farmers have a positive attitude towards ecological farming, but there is still room for further improvement. (2) Long-term farming has a significant negative impact on farmers’ adoption of ecological farming. Neighborhood communication, including frequency of communication and degree of communication, has played a significant positive role in the adoption of ecological farming. (3) The improvement of neighborhood communication can alleviate the adverse effects of long-term farming on the farmers' adoption of ecological farming. there are differences in the adjustment of neighborhood communication in different dimensions, and only the adjustment of the degree of communication variables is significant. (4) The cultural level, the type of livelihood, the proportion of family labor, the topographic conditions of the village, the intensity of propaganda and whether to participate in training are also important factors affecting the adoption of ecological farming. Research conclusions: In order to encourage farmers to carry out ecological farming, it is necessary to formulate targeted policy measures in terms of innovative ecological farming training and promotion methods, building a neighborhood communication platform and constructing a long-term demonstration mechanism for ecological farming.

Abstract：Based on the survey data of 1 007 farmers in Hubei Province, this paper, employing the Ordered Logit model, analyzed the effect of farmers’ sense of belonging to the village on their participation in rural environmental governance from the perspectives of ownership, village identity, village love, business concern and village attachment. The results show that: (1) 98.42% of the farmers has participated in rural environmental governance, with only 25.60% of the farmers participating in the two or more environmental governance behaviors, thus the participation level needs to be further improved. (2) At present, the level of farmers’ sense of belonging to the village is generally high, while there is still room for further improvement. (3) The sense of belonging to the village plays a significant role in promoting farmers’ environmental governance behaviors. The stronger the sense of ownership is, the higher the sense of identity of villages is, the deeper love they put in villages, the more they are concerned about village affairs and the higher they are attached to villages, the more they are likely to participate in rural environmental governance. (4) Farmers’ personal characteristics have a certain regulatory effect on the above relationship. When the farmer is an older, highly educated woman with long residence time and surname, sense of belonging to the village is more likely to influence their environmental governance behaviors. Therefore, in addition to continuing to optimize conventional economy and institutional regulations, the sense of belonging, an internal incentive mechanism, should be cultivated and strengthened to promote farmers’ environmental governance behaviors, and thus achieving the goal of ecological livable rural areas.

Abstract：The green development of agriculture depends on the green transformation of farmers’ production behavior, which is not only related to the internal factors of farmers themselves and their families, but also stimulated and restrained by external factors. Based on the survey data of 719 farmers in Hubei province, and according to the characteristics of farmers’ pursuit of interests and loss aversion, this paper puts the external incentives and constraints faced by peasant households in the production process into a framework, discussing the influence of incentive and constraint measures on the green production behavior of farmers applying biological pesticide and the regulating effect of constraint measures. The findings are as follows: first, the positive stimulation of price incentive, technical training and policy subsidies, and the negative regulation of production supervision and punishment can significantly affect the production behavior of farmers and improve the possibility of farmers' application of biological pesticide.Second, price incentive has the greatest effect, followed by punishment and restraint, technical training and policy subsidies, and production supervision has the least effect. Third, restraint measures can adjust the influence of incentive measures on farmers' application of biological pesticide to a certain extent, and the direction of regulating effect is different under different incentive and restrictive measures. Production supervision and policy punishment positively regulate the role of price incentives, market supervision positively regulate the role of technical training, while production supervision has weakened the original effect of technical training. Therefore, we should attach equal importance to incentives and constraints when promoting green production of farmers, and make a reasonable combination of incentives and constraints to enlarge the synergistic effect of incentives and constraints.