This research assumed a conception that there exists a sub-line of Hu Huanyong population line based on the theoretical connotation of Hu Huanyong population line, and also supposed the spatial characterize of this sub-line. In accordance with the sub-line, and the spatial patterns of natural and social foundation in Yangtze River Economic Belt (YREB), we predicted the future population carrying of natural resources. And then we further divided the spatial pattern of population carrying in the perspective of sub-line of Hu Huanyong population line. We found that stepped spatial structure has been formed in Yangtze River Delta. Therefore, we have made a series of suggestions for optimizing the strategic spatial structure in YREB.

 

Based on the land change survey data from 2005-2015 of 11 provinces of the Yangtze River economic belt zone, this study comprehensively assesses the land development intensity of this district from two aspects of land development equilibrium degree and land development limit. It shows that: (1) The equilibrium degree of land development in the Yangtze River economic belt presents polarization; Land development in eastern and Western Regions is lopsided; Land development in Central China is relatively balanced. (2) The land development limitation of the Yangtze River Economic Zone is 5.58%, and all provinces exceed or close to the limit value, so intensive land development model should be established in these areas in the future. (3) There are significant differences of land development intensity in different regions of the zone, presenting a spatial pattern which is high in lower reaches and low in upper reaches, and high concentration in the east. Therefore, the land planning should be revised according to the land development limitation of each province; strengthen the land supply capacity to exploit new development potential in these areas whose construction land is inadequate; establish cross-region land development system, and exploit and utilize land more rational through improving policies and regulations.

Innovation has become an important driving force for regional economic development in the era of knowledge economy. This paper uses DEA-Malmquist index to measure regional innovation performance and spatial structure evolution of Yangtze Economic Zone, grouping regions with similar performance by Ward clustering method, analyzing innovation performance and problems. The results show that overall level of innovation performance in Yangtze Economic Zone is low, the development of core economic area mainly depends on R&D inputs and resource consumption, while the problem of how to improve utilization rate of existing technology is ignored. On one hand, regions at different development stages may have similar innovation performance, but experience different problems such as mismatch of resource scale and R&D input/output, input redundancy, lack of innovation output and so on. On the other hand, because the performance of regions at similar developmental stages are not the same, the specific ways to improve innovation performance are different. During 2000-2014, overall level of regional technology has improved significantly, while developing trend of regional production performance was gradually reduced. Technical level and performance show reverse trend of expansion, improvement of technology innovation mainly depends on input of resources, while how to improve the existing resources is worth further consideration. Specifically, 4 groups can be divided according to regional innovation performance. Overall level of innovation performance in cities at postindustrial stage is higher. Main problem of these cities is mismatch of resource scale and R&D input/output. Therefore, the most effective way for achieving optimal performance is adjusting resource scale. Less developed regions need optimize allocation of innovation resources by interregional cooperation. In addition, main problems for low innovation performance regions are lack of high-tech production output and application knowledge. Hence, main approach to improve innovation performance of these regions is continue expanding R&D resources and encouraging new product development.

The study on evaluation of ecological carrying capacity is of great significance to the regional sustainable development. In this paper, 130 cities of the Yangtze River Economic Zone are taken for example. We conducted a quantitative study on ecological carrying capacity based on both ecological support and ecological pressure, by building a relatively comprehensive evaluation system of ecological carrying capacity with the evaluation index weighted via entropy method. The ecological support, ecological pressure and ecological carrying capacity of the cities located in Yangtze River Economic Zone were evaluated. Furthermore, the spatial pattern of ecological support, ecological pressure and ecological carrying capacity of the Yangtze River Economic Zone in 2003, 2008 and 2013 were discussed and the impact factors were analyzed. The results showed: (1) in both 2003 and 2008, the spatial pattern of ecological support in the Yangtze River Economic Zone exhibited the best performance of the upstream area, which was better than the downstream area and even better than the midstream area; between 2003 and 2008, ecological support of midstream area and upstream area increased, while that  of downstream area decreased; between 2008 and 2013, the overall ecological support increased, and in 2013 the ecological support of the midstream area exhibited the best performance  than upstream and even better than downstream area. (2) Between 2003 and 2013, the ecological pressure had been increasing, and the pressure of downstream area was the largest which surpassed that of midstream and upstream area. (3) The ecological carrying capacity decreased initially and then presented an increase between 2003 and 2013, and the upstream area showed the highest carrying capacity than midstream area and even higher than downstream area. The main factors influencing ecological carrying capacity were changed from environmental management and energy conservation to social progress and economic development. The initiatives of enhancing ecological carrying capacity have gradually changed from the elementary stage of reducing pollution emission to the advanced stage of improving environmental quality.

The Three Gorges Reservoir area is the special geographical unit of the Yangtze River economic belt. The mismatching of its social infrastructure construction and urbanization development will have negative impact on the long-term sustainability inthis area. Based on the panel data of Three Gorges Reservoir Area in 2000-2014, this research built up the framwwork of measure system of Social Infrastructure and New Urbanization. The correlation model was used for detection, and the quantitative analysis of the Coordination Degree in 15 years was done through the Static Coordination Degree model to test. The results show that: (1) the Social Infrastructure construction is closely related to the Urbanization process; (2) in time, the Coordination Degree of the Social infrastructure and New Urbanization by the measurement system in the reservoir area shows a development trend from coordination to imbalance; (3) in space, the difference is obvious for the different counties and districts in the reservoir area, and it is necessary to promote the coordinating development of Social Infrastructure and New Urbanization by consideration of the specific situation of the social and economic development in different areas.

In this paper, we have constructed the nonparametric decomposition framework to measure the growth drivers of tourism economy, and the drivers were analyzed and calculated based on the input and output data of the tourism industry in 30 provinces of China from 2005 to 2012. The results show that the contribution of TFP (total factor productivity) has been gradually overtaking that of the factor inputs in this period and became the main driver of economic growth of Chinese tourism, with its corresponding contribution rate jumping from 49.01% in 2006 to 82.18% in 2012. Technological progress was the key to the escalation of such a contribution, while technical efficiency, especially the scale efficiency within it, had a relatively smaller and slipping contribution to the tourism economic growth. Moreover, the contribution of pure technical efficiency was almost negligible, sliding from 50.99% in 2006 to 26.52% in 2012. The drivers of tourism economic growth differed from region to region, with the middle and western regions growing faster than the eastern region. The rise of tourism economy in central China was mainly driven by scale efficiency, while that in the western region was mostly driven by pure technical efficiency, which could be further divided into two distinct phases according to the different driving factors. The first phase was driven by factor input in the 2005-2008 period and the second phase by TFP in the 2009-2012 period. The tourism economic growth of China became increasingly intensive from 2006 to 2012, when the contribution of TFP surpassed that of factor inputs and the growth relied even more on TFP.

To reduce the energy consumption in tourism industry and to promote green tourism development, this study investigates how to improve tourism energy efficiency. Based on the environmental directional distance function, this paper firstly constructed a Biennial Malmquist-Luenberger (BML) productivity index according to tourism characteristics. Then the tourism energy efficiency was evaluated with a sample of 30 cities over 9 years from 2005 to 2013. The changes of tourism energy efficiency can be attributed to five factors, namely total factor productivity, capital substitution effect on energy, labor substitution effect on energy, energy structure effect and output structure effect. Results show that: (1) the overall energy efficiency of China’s tourism industry is at quite a low level in average, indicating a great potential to expand. (2) The improvement of total factor productivity, capital substitution, labor substitution and energy structure effect can promote tourism energy efficiency. (3) The impacts of capital substitution, labor substitution and energy structure on tourism energy efficiency have overtaken the total factor productivity in the past three years. (4) In terms of a spatial scale, the tourism energy efficiency in the eastern China is higher than that in the Midwestern China over the sample period, primarily caused by the difference of capital substitution and energy structure. (5) The tourism energy efficiency of 17 cities shows a downward trend from 2005 to 2013, nevertheless, affected by different factors. The capital substitution is the dominant contributor to tourism energy efficiency decline in most provinces, such as Hubei, Fujian and Zhejiang, whereas the total factor productivity is the main contributor in the provinces of Anhui, Hainan, Guizhou and Gansu. In sum, the rational utilization of resources is essential for low-energy consumption development in tourism industry. The substitution effect of capital for energy should be brought into full play since efficient allocation of capital can greatly improve the energy efficiency of tourism industry.

This study focus on the efficiency measure of tourism for 31 China’s provincial forest parks from 2000 to 2014 by using the DEA (data envelopment analysis) and spatial analysis method to clarify the evolution of spatial-temporal pattern. The results showed as follows :(1)The tourism efficiency of China’s provincial forest parks had been improved in fluctuation from 2000 to 2014. (2)The difference of comprehensive efficiency between provinces and regions was significant, which was driven by pure technology in developed region, while in undeveloped region was mainly driven by scale. (3)The efficiency of dimensional evolution showed the trend that high and low value were concentrated, some neighboring provinces showed more closely, “Matthew effect” was significant, its center of gravity was moving to the southeast direction on the whole, the comprehensive efficiency and the pure technical efficiency in each year present U evolution trend, scale efficiency present M evolution trend. Based on the above analysis, this paper promoted the path improvements of tourism efficiency, which has great significance for the sustainable development of tourism resources in provincial forest parks.

It is one of the prerequisites for the implementation of tourism ecological compensation policy that to understand the willingness of tourists to pay for the tourism ecological compensation. This paper took Huangshan scenic area as an example to analyze the willingness to pay and the reason of rejection. In order to provide the basis for constructing the mechanism of tourism ecological compensation in national parks, the binary logistic regression was used to analyze the influencing factors of their willingness to pay, such as tourists’ personal characteristics, tourism environmental impact cognition, tourist satisfaction, tourist revisiting willingness and the cognition of ecological compensation. The results show that: (1) tourists have relatively high willingness to pay for tourism ecological compensation in Huangshan scenic area. When visiting the Huangshan, 86.7% of tourists expressed willingness to pay, while only 13.3% of them rejected. (2) According to the regression results, the gender, age, revisiting willingness and the compensation necessity cognition have significant influence on willingness to pay. The willingness to pay of women is higher than that of men, and the age has an obviously negative effect on the willingness to pay. However, the revisiting willingness and the compensation necessity cognition have significantly positive impacts. The willingness to pay at 10% significance level is barely influenced by the other 7 factors, such as education level, monthly income, tourism environmental impact cognition, tourist satisfaction and the compensation policy cognition. However, the statistical results suggest that education level, environmental quality assessment, the fear of environmental damage, the importance of ecological environment and tourist satisfaction have positive effects on the willingness to pay for the tourism ecological compensation. The monthly income and compensation policy cognition have the inverted “U” type nonlinear relationship with the willingness to pay.

Leisure agriculture is an important part of modern cities economic activities. Upon the published leisure agriculture data and land use data from Shanghai Municipal Agricultural Commission, this study analyzes the leisure agriculture spatial pattern in the city of Shanghai and explores the possible factors. Analytical methods include Near neighbor index(NNI), the geographic congregation degree(G), index of diversification(GM), Lorenz curve and Gini coefficient, grey relational analysis and Method of ordinary least squares(OLS) regression analysis. The results show: (1) The NNI of leisure agriculture scenic spots is 0.673 8, indicating the leisure agriculture scenic spots is concentrated in Shanghai. The congregation degree is accounted as 42.31. (2) Index of diversification of Shanghai leisure agriculture varies greatly from 0.2 to 0.7 in the 9 regions. Diversification order in the 9 regions (from high to low) is Fengxian > Jiading > Songjiang > Qingpu > Baoshan > Pudong > Jinshan > Minhang. The Gini coefficient is 0.558 2 and the spatial patterns of land use vary in the 9 regions. The Gini coefficients of heritage villages and tourism agriculture parks are over 0.8, suggesting the two areas have the lowest leisure agriculture land use distribution. (3) Leisure agriculture can be influenced by many factors, e.g. the funding amounts, the development of society and economy, the transport facilities and local tourism development, etc. The results of grey relational analysis suggest spatial pattern of Shanghai leisure agriculture can be greatly affected by road lengths, citizen’s income, agricultural areas and productions. The tourist amount and population size have the medium and low impacts on Shanghai’s leisure agriculture spatial patterns, respectively. The OLS regression analysis suggests that agricultural resources and transport facilities have significantly positive impacts on the spatial pattern of leisure agriculture, while tourist amount, people’s average income, and agricultural production have significant negative impacts on the spatial pattern of leisure agriculture. The results of quantitative geography analysis reveal some problems of leisure agriculture in Shanghai. Five suggestions are given to improve leisure agriculture industry in Shanghai: 1) develop resources according to local conditions; 2) form an annular spatial pattern; 3) coordinate leisure agriculture and tourism industry; 4) improve the transport infrastructure; 5) promote agglomeration effects.

Large-scale agriculture management is an important method to implement agricultural modernization. This study aims to explore the influential mechanism of large-scale agriculture in hilly areas on soil erosion using literature review. All related studies are collected and organized. New research perspectives are then established based on the analysis of the disadvantages found in current studies. To sum up the previous studies, we learn a) the efficacy, policy and promotion mechanisms of large-scale agriculture management; b) that soil erosion is a result of the interaction between natural and artificial factors based on agricultural activities; and c) the methods to investigate and monitor soil erosion as well as evaluations and analog simulations of influential factors. Finally, five research perspectives are proposed: a) establishing a driving force model for soil erosion in hilly areas; b) setting up an evaluation index system based on the influence of large-scale agriculture in hilly areas on soil erosions; c) analyzing the influential level and spatial-temporal difference; d) inversely simulating the soil erosion effect caused by large-scale agriculture in hilly areas; and e) suggesting the policies made for large-scale agriculture in hilly areas that acquire sustainable soil and water resources, which are expected to serve as valuable scientific references to appropriate large-scale agriculture in hilly areas and sustainable development.

The deprivation of ecological environment and resources by rapid urbanization and the restriction of resources and environment on urbanization are hot issues in recent years. It is of great significance to measure the degree of coordination between urbanization and resource environment and to determine the type of coupling and coordination to guide healthy urbanization. This paper first constructs the comprehensive index system of urbanization and the sub-index of resource and environment pressure, which includes 16 sub-indicators. The abrupt progression method was used to calculate the urbanization comprehensive index. The entropy weight method was used to calculate the pressure index of resources and environment. The gray system method was used to calculate the correlation between the comprehensive index system of urbanization and the comprehensive index system of resources and environment pressure. According to the general system theory, the dynamic coupling model of urbanization and resources and environment is constructed, and the coupling degree and the type discrimination of urbanization and ecological environment in Wuhan from 2004 to 2013 are quantitatively analyzed. The results show: (1) the comprehensive index of urbanization in Wuhan increased year by year, especially in 2005-2007, the urbanization level increased rapidly. The maximum value of comprehensive index of resources and environment pressure appeared in 2006 was 0.629, the minimum value appeared in 2013 was 0.452. (2) The correlation value between the 0.480-0.911, most of the coupling degrees in the medium and strong in the two range. Soot emissions and industrial output value, built area, per capita electricity consumption, per capita GDP, urban population scale performance of the strong coupling (greater than 0.85). Among the urbanized sub-indicators, the proportion of urban population and resources and environment are the most relevant. In the resource and environment sub-indicators, soot emissions and urbanization level of the coupling effect is the strongest. (3) The dynamic coupling model based on general system theory reflects the dynamic feedback process of urbanization-resource environment composite system. From 2004 to 2013, Wuhan has experienced four stages of coordination-conflict-coordination-conflict. The results show that the urbanization of Wuhan City-resources and environment complex system with the advance of urbanization, urbanization and resource environment, the contradiction is further apparent.

In order to understand the current situation of ecological environment and sustainable development ability of Hunan Province，based on the application of improved traditional ecological footprint model and the statistical data of Hunan Province in 2015 ,this paper calculates and analyzes the emergy ecological deficit of Hunan Province in 2015. The research result indicates that, in 2015, the emergy ecological capacity is 9.90×108 hm2，The emergy ecological footprint is 1.84×109 hm2，and the ecological deficit is 8.49×108  hm2 and the 10,000 yuan GDP’s ecological footprint is 6.36  hm2 . The analysis result shows that Hunan Province has a large ecological deficit in 2015, and its development is relatively unsustainable, and its dependence on natural resources and energy is relatively high. Among them, arable land and fossil energy land are the greatest contribution factors to the ecological footprint of Hunan Province. Construction land is in the second place. The effects of water area, grassland and woodland are relatively small. The ecological footprint of the 10,000 yuan GDP in Hunan Province in 2015 is continuously decreasing, which demonstrates that the efficiency of Hunan Province’s utilization of resources and energy is gradually improving, and the ecological costs of economic development are gradually decreasing.

Based on the index system of the security prewarning and regulation of urban agglomeration ecological carrying capacity, this paper calculates the security index of the ecological carrying capacity of Chang-Zhu-Tan urban agglomeration from 2006 to 2015, and predicates the security warning degree of each year by collecting the relevant raw data and using the grey weighted relevance theory. The calculation result indicates: the ecological carrying capacity security index of the Chang-Zhu-Tan urban agglomeration shows an upward tendency from the overall view. The security warning degree decreases from “high level” to “low level”. While from the subsystems of pressure, status and response, the security index also shows an increasing tendency. The security warning degree decreases from “high level” or “middle level” to “low level”. The analysis shows the implementation effect of the resource and environment policies of “two-oriented society” experimental area of Chang-Zhu-Tan urban agglomeration is evident. However, it is also found that the security indexes of experimental area are below 0.700 0, which are far away from the “no alarm” (0.850 0) level. There is still a long way to go in the construction of “two-oriented society” of Chang-Zhu-Tan urban agglomeration.

The regional differences in socioeconomic and resource endowments lead to significant spatial heterogeneity of farmland conversion.It is the basis for optimizing the allocation of land resources to carry out nonagricultural pressure measurement and reveal its spatiotemporal evolution pattern.In this paper, the evaluation index system of farmland nonagricultural pressure is constructed from four aspects of economic factors, social factors, industrial structure and resource endowment.The entropy method is used to calculate the weight of each index, and then calculate the farmland nonagricultural pressure in China from 1990 to 2014. Then based on this, the spatiotemporal pattern of farmland nonagricultural pressure is analyzed. The results show: (1)From the point of view of the spatial, the spatial distribution of farmland nonagricultural pressure shows a clear gradient, which shows a decreasing trend from east to west in general. (2)From the trend of time, the change of farmland nonagricultural pressure in different provinces show diversified trend. In eastern China, the pressure of farmland in Shandong, Zhejiang and Jiangsu were on the rise, while the pressure of Shanghai and Fujian gradually became stable. The pressure index of Guangdong showed a downward trend.The nonagricultural pressure index in the central regions, Henan, Hebei, Shanxi and Jiangxi stabilized, and Shaanxi, Hubei, Sichuan and Chongqing were on the rise. The nonagricultural pressure of cultivated land in the three western provinces (Yunnan, Tibet and Xinjiang) showed a consistent downward trend. (3)From the combination of spatiotemporal patterns, the changing trend of farmland nonagricultural pressure shows a different trend. In the areas with larger nonagricultural pressure, the nonagriculturalization of farmland experienced a stage from the systemdriven to the developmentimpetus. The Ushaped trajectory of economic growth was obvious. The relationship between economic growth and farmland nonagriculturalization was gradually decoupled. Conversely the areas with less pressure, the development of the industry is lagging behind, and land comparative income is low. Then the social security function and the ecological effect of farmland have great impact on the nonagriculturalization of farmland, thus affecting the nonagricultural change of farmland in some provinces.

The study of smallscale land use change in rocky desertification control area will help to deeply analyze the temporalspatial variation law, driving force and resource environment effect of land use change in karst area. By using stepwise multiple regression method, this research analyzed the land use change and its driving mechanism in rocky desertification control area. The results showed that: ①From 2005 to 2012, the area of rocky desertification decreased 46.63 hm2, which from 2 824.23 hm2 to 2 777.60 hm2. Meanwhile, the degree of rocky desertification declined, the no obvious rocky desertification and moderate rocky desertification lands increased 12.68% and 3.08%, and the potential rocky desertification, slight rocky desertification and intense rocky desertification lands decreased 5.11%, 2.07% and 5.24%, respectively. Among the three types of rocky desertification change(which including stable type, restored type and degenerated type), the proportion of the stable type in the karst area was 95.4%，and it had the smallest proportion of land use change, which was only 1.15% showing the land use was stable. The proportion of the restored type in the karst area was 3.95%, and it had the biggest proportion of land use change, which was 40.64% showing as the land use changed drastically. The proportion of degenerated type in the karst area was only 0.65%, and the proportion of land use change was 22.21% showing as the land use changed more obvious. ②The main feature of land use change was presented by the reduce of garden plot. There were four factors to drive the land use change, which including the changes of the average labor′s average schooling years, the proportion of household laborers, the local nonagricultural income and the income of migrant farmers. Among the four factors, the garden plot change showed a significant positive correlation with the local nonagricultural income change, which the regression coefficient was 0.691, and showed a significant negative correlation with the changes of the average labor′s average schooling years, the proportion of household laborers and the income of migrant farmer, which the regression coefficient was -0.472,-9.735 and -0.443, respectively. The proportion of household laborers was the major factor driving the land use changed. ③There are two factors, include China′s demand for building ecocivilization by implementing Grain for Green Policy, industrialization and urbanization, and farmers′ demand for becoming rich by improving their cultural quality and adjusting their employment behaviors, to macroscopically and microscopically encourage the rural labor transfer and industry transformation, and then collectively drive the land use change in the rocky desertification control areas.

The spatial distribution of rural residential area and its influencing factor is one of the main studies of rural settlements geography, and it is also an important field of GISRS applications. This paper selected the rural settlements of Pan County as the study area, analyzed the characteristics of spatial distribution and landscape pattern by using the method of kernel density estimation, coefficient variation (Cv), and landscape pattern index to examine the influence of topography and landforms factors. The results showed that: (1) The spatial distribution of rural residential area in Pan County had showed the pattern of “middlenorthwest intensive and southnortheast extensive”, which was the same distribution as the plain, valley and lowmid elevation in the study area. (2) By using the Point Pattern Analysis (PPA), the Cv value of the spatial distribution of rural residential area at village, township and the different topography classification) were greater than 64%, which belonging to the cluster distribution. (3) In various topographic factors, altitude, slope and relief amplitude are the key factors to influence the distribution of rural settlements; with the increasing of altitude, slope and relief amplitude, the land area, proportion and irregular degree of rural residential area showed increased first and then decreased; more than 75% of rural residential area were located on the region of average elevation, smaller relief amplitude (50-100 m), lower slope (5-15 degrees), south slope and small undulating mountain.

Jingjiang section of Yangtze River is host to plenty of migratory fishes. For the sake of grasping the characteristics of food web structure in the nearshore zone of Jingjiang section, together with providing basic biological data for further study and fishery resource assessment, this study employed stable isotope technique of carbon and nitrogen to detect the δ13C and δ15N values of each biological sample collected there in August 2016 and constructed the continuous trophic spectrum of crabs, small fishes, shrimps and other fishery creatures. As the results revealed, the δ13C value of zooplankton was -30.34‰ and the lowest, followed by the benthic clastic of -30.24‰. The average δ13C values of shellfish, aquatic plants, small fishes and shrimps were -29.75‰±0.75‰, -28.98‰±0.88‰, -26.74‰±2.37‰ and -26.1‰±0.16‰, respectively. Crabs owned the highest δ13C value of -25.86‰±0.74‰. The δ15N value of aquatic plants was 5.16‰±0.85‰ and the lowest, and benthic clastic of 5.58‰ in the next place. The average δ15N values of shellfish, small fishes, zooplankton and crabs were 8.13‰±0.31‰, 11.56‰±1.59‰, 12.02‰ and 12.51‰±1.43‰, respectively. Shrimps possessed the highest δ15N value of 13.05‰±0.45‰. The order of trophic level was aquatic plants, benthic clastic, shellfish, zooplankton, small fish, crabs and shrimps from low to high. Small fishes, crabs and shrimps in this part of water area shared the similar food source while the stable isotope values suggested an obvious overlap in trophic niche among them.

 Employing panel data gathered from 1998-2015 in 30 provinces in China, adapting SuperSBM model to calculate agricultural water efficiency and relying on the observations of the dynamic and static evolution of agricultural water consumption and agricultural water efficiency, this article attempts to determine the impact of agricultural water efficiency on agricultural water consumption utilizing threshold panel regression model. The findings illustrate the periodical decrease in both agricultural water efficiency and agricultural water consumption in China. An effective approach to increase efficiency in agricultural water is to reduce agricultural water consumption since agricultural water efficiency has a significant threshold effect on reducing agricultural water consumption. The decreased efficiency in agricultural water efficiency in eastern area promotes agricultural water′s downscale, but the effect of resilience should not be overlooked. The agricultural water efficiency in central China reduces the increase in agricultural water consumption with its strengthening effect. Increased agricultural water efficiency in western China can promptly reduce agricultural water consumption with its diminishing effect. Additionally, agricultural water consumption can be reduced by enhancing peasants′ educational level, by enabling more coverage of green lands and by enlarging agricultural laborers′ population while excellent water resources endowment can increase agricultural water consumption.

The atmosphere particulate matter characteristics over the city of Anqing(Southwestern Anhui Province, China) between 2015 and 2016 were analyzed in this study. HYSPLIT4 backward trajectory model was used to simulated the air pollutions transport patterns and potential source area. The results showed:(1) The particulate matter concentrations had significantly seasonal changes, which was high in winter and low in summer. The highest and lowest particulate matter concentrations appeared in December and July, respectively.(2) The airmass trajectory in Anqing area exhibited significant seasonal variation. In the summer, Anqing is dominated by oceanic airflow from the southern and the southeastern regions. In the other seasons, the Anqing area is affected by the oceanic airmass and the continental airmass. The continental airmasses could be divided into the western and northwest path, commonly corresponding with heavy air pollution events in Anqing.(3) The PSCF and CWT values were also higher in winter but lower in summer. High PSFC and CWT values airmass mainly from two stripe areas, one area involved the eastern Hubei, northern Jiangxi and southern Hunan province, another one included the Shanxi, Henan, Shandong and northern Anhui province.

To elucidate characteristic of existence, movement and adhesion of Limnoperna fortunei in different eutrophic states were conducted using laboratory control experiment.(1) The results indicated that the Oligotrophic state were not suitable for the adhesion of Limnoperna fortunei, but Oligotrophic state were suitabled for Limnoperna fortunei’s survival, so Limnoperna fortunei moved the shortest distance. Mesotrophic state were suitabled for survival of Limnoperna fortunei. The eutrophic state were not suitabled for the survival of Limnoperna fortunei, so Limnoperna fortunei moved the farthest distance.(2) The lower nutrient concentrations belong to eutrophic state were suitabled for survive of Limnoperna fortunei. The higher the concentrations of nutrient, the less were suitabled for adhesion of Limnoperna fortunei. The lower nutrient concentrations belong to eutrophic state were suitabled for adhere of Limnoperna fortunei.(3) The lower phytoplankton concentrations belong to dystrophic state were suitabled for survive of Limnoperna fortunei. The higher the phytoplankton concentrations, the less were suitabled for survival of Limnoperna fortunei. The higher the concentrations of phytoplankton, the less were suitabled for adhesion of Limnoperna fortunei. The lower phytoplankton concentrations were suitabled for adhere of Limnoperna fortunei. The lower concentrations of phytoplankton were suitabled for survival of Limnoperna fortunei, so it moved the shortest distance. The higher concentrations of phytoplankton were not suitabled for survival of Limnoperna fortunei, so it moved the farthest distance. The results indicated the degree of eutrophication were the key regulatory factors for existence, movement and adhesion of Limnoperna fortunei. The lowereutrophic state were suitabled for existence and adhesion of Limnoperna fortunei. The concentrations of nutrient and phytoplankton played governing roles for existence and adhesion of Limnoperna fortunei. The lower concentrations of nutrient and phytoplankton belong to dystrophic state were suitabled for existence and adhesion of Limnoperna fortunei.

According to the characteristics of multiattribute decision making, uncertainty and fuzziness during the process of eutrophication assessment, an integrated method is proposed for eutrophication comprehensive evaluation on the basis of multi-element connection number and triangular fuzzy numbers. Multielement connection number is applied to depict the uncertainty of subordinative relationship between the evaluation factors and evaluation grade. The triangular fuzzy numbers are used to express the continuous changing process and fuzziness of difference degree coefficient of connection number. Then, comprehensive connection number between the evaluation factors and grade is calculated, the characteristic value of evaluation grade is determined based on combination weight of the evaluation indexes. Eutrophication status of cascade reservoirs on the Huangbaihe River in July, 2016 was evaluated as a case. The results showed that the eutrophication status of Xuanmiaoguan Reservoir was oligotrophic, and Tianfumiao Reservoir, Xibeikou Reservoir, Shangjiahe Reservoir were all mesotropher. Their eutrophication in the order were Shangjiahe Reservoir> Xibeikou Reservoir > Tianfumiao Reservoir > Xuanmiaoguan Reservoir. Compared with the results from some other widely used methods, the evaluation result in this paper was intuitive, effective and can reflect actually eutrophication status. Meanwhile, different from other methods, it could distinguish accurately internal differences at the same eutrophication level. This method has a good application prospects in assessment of lake and reservoir eutrophication.

The “springmaize & laterice” rotation is a new planting type in southern China recently. The phosphorus(P) fertilizer allocation in the two season crops(maize and rice) is important for understanding how P fertilizer efficiencies affect on crops yields. An annual maizerice field experiment was conducted in Wuxue County, Hubei province between March and October 2015. According to the P fertilizer amount used in the two crops, seven treatments were applied in the experiment, which includes no P application in both crop seasons(P0), conventional P application in both crop seasons(P1), 1/3 P for late rice was forward applied as basal fertilizer in maize season(P2), 2/3 P for late rice was forward applied as basal fertilizer in maize season(P3), all P for late rice was forward applied as basal fertilizer in maize season(P4), all P for late rice was forwarded and the total annual P was decreased by 15%(P5) and all P for late rice was forwarded and the total annual P was decreased by 30%(P6), respectively. We analyzed the crop yields, phosphorus uptake and phosphorus use efficiency in different treatments. Compared with the conventional P application(P1), the P3 and P4 treatments significantly increased the rice yield and the allocation of rive dry matter, maize, and rice yields increased by 4.87% and 6.74% respectively. There was no significant difference in rice yields between P5 and P1, but the yield of late rice was significantly decreased when the annual total P application decreased by 30%(P6). The forward application in maize season of P fertilizer for the late rice season significantly promoted the uptake of P by maize and late rice, and significantly reduced the apparent surplus of soil P. The soil phosphatedependent rate of two crops decreased significantly under P2, P3, and P4 treatments, in comparison with P1 treatment, by 11.63%, 26.47%, and 22.08%, respectively. From the perspective of P use efficiency, the P fertilizer cumulative recovery efficiency, agronomic efficiency, partial factor productivity and fertilization contribution rate of P4 treatment were significantly higher than those of P1, which was increased by 102.46%, 194.83%, 6.73% and 176.16%. Compared with P1 treatment, the treatment of P5 had no significant effect on the annual P fertilizer contribution rate and agronomic efficiency but increased the P recovery efficiency and partial factor productivity by 32.56% and 58.05%. The study proved that P application in maize season had significant residual effects in late rice season, and it had higher P use efficiency than that the P application in the rice season. All P fertilizer for late rice could be moved to maize season, and even the total P application amount was reduced 15%.

Seasonal change and spatial distribution pattern of vegetation in the Chongqing region was studied using the distribution index method and the MODISEVI data during 2000-2015. The results showed that:(1) vegetation reduction presented the highest proportion(6.33%) in winter. The reduction was mainly distributed in the valleys, towns and surrounding areas influenced by the reservoir construction and builtup expansion. Stable vegetation presented the highest proportion(88.23%) in autumn. Vegetation increase presented the highest proportion(31.50%) in spring. The increase was mainly distributed in the west hilly region and farming areas in the middle parallelism valley.(2) The areas with dominant vegetation changes are different. Vegetation reduction was mainly distributed in the areas below 400 m elevation and below 6° slope. Vegetation increase was mainly distributed in the areas between 400 and 1 000 m elevation and between 6° and 15° slope. Stable vegetation was mainly distributed in the areas above 1 000 m elevation and above 15° slope.(3) From spring to summer, vegetation reduction moved to lower terrains(< 800 m elevation, < 6° slope), but vegetation increase moved to higher terrains(> 800 m elevation, > 6° slope). From summer to autumn, vegetation reduce moved to higher terrains(> 500 m elevation, > 6° slope), but vegetation increase moved to lower terrains(< 500 m elevation, <6° slope). From autumn to winter, vegetation reduction(> 1 300 m elevation, > 15° slope) was stronger than vegetation increase(> 500 m elevation, > 6° slope) on the high terrains. Vegetation reduction(< 1 300 m, <15°) was weaker than vegetation increase(< 500 m, < 6°) on the low terrains.(4) On the distribution of aspect, vegetation change extent did not present significant seasonal variation across the North, East, South and West directions.
Key words：vegetation coverage; MODISEVI; trend analysis; distribution index; seasonal change