The rule of law of natural resources is an important facilitating measure and institutional guarantee for the construction of ecological civilization. However, its realization can not be achieved without the integrated and organic combination of scientific knowledges of different disciplines, in particular theories and methodologies between natural sciences and social sciences, together with the theories of rule of law. The scientific nature of the rule of law in natural resources area is an essential requirement of respecting the laws of nature, economy and society. Employing the nexus approach into the natural resources management is a necessary choice to realize the concept of life community of mountains, rivers, forests, fields, lakes and grasses, etc., and it also provides an important path for analyzing the scientific nature of the rule of law in the field of natural resources. Applying the research methods of literature review and nexus study, based on the China’s actual national conditions and objective needs, this paper studies how to construct the rule of law of natural resources in China following the concept of life community with a nexus perspective. The finding is that, in order to realize the rule of law of natural resources from the perspective of nexus governance approach, effective and efficient measures should be taken by China at least from the following three aspects, i.e., (i) adding nexus clauses in the departmental legislations so as to integrate departmental legislations and change the status quo of separatism of the current departmental legislations, (ii) establishing systems and mechanisms for collaborative governance of natural resources for promoting effective cooperation among different departments concerning various aspects of natural resources management as well as increasing efficiencies in the cooperative process, and, (iii) securing the achievements acquired by implementation of nexus approach through multi-subjects participatory governance for the sake of promoting public participation and consciously following the rule of law while realizing democracy.

This research combines the Technology Acceptance Model with the Theory of Planned Behavior. With the sampling 303 questionnaires of Shanghai residents, an integrated model to discover the influential factors of the Willing-to-pay for green technology products is constructed. The path analysis was carried out by using AMOS structural equations, which shows that factors affecting the willingness of residents to pay for green technology products can be attributed to technical acceptance factors (Information Communicating, Perceived Usefulness) and planned behavioral factors (Trust Tendencies, Behavioral Tendency). Behavioral Tendency and Perceived Usefulness are two important factors which can generate and improve residents’ willingness to pay, while residents’ attitudes towards the use of green technology products cannot promote their willingness to pay, and the impact of Information Exchange on residents’ attitudes towards the use of green technology products is not significant. Based on the analysis, the related policies and recommendations for improving residents’ willingness to pay for green technology products are proposed.

Investing in natural capital (NC) and improving the ecosystem services value (ESV) are important measures to promote economic growth and environmental protection cooperatively. One of the keys is to measure ecosystem services value. Based on the survey data of various land-use types in Chongqing from 2009 to 2016, The spatiotemporal distribution pattern of ESV in Chongqing is measured and calculated, then the spatio-temporal dynamic relationships between ESV and economic growth are identified during the study period. The results indicate that: (1) the ESV of Chongqing was respectively RMB 401.129, 400.063 and 403.724 billion in 2009, 2012, and 2016, respectively, documenting a U-shaped curve of decrease first and then increase, and ESV in the northeastern and southeastern parts of Chongqing was obviously higher than that of main city zones and western Chongqing. (2) The main reason for the trend is the change of forest land area. The occupancy of construction land led to the decline in the early stage, while the implementation of ecological projects such as conversion of farmland to forests, protection of natural forest resources and subsequent vegetation restoration of the Three Gorges Project promoted the increase of ESV in the later stage. (3) The negative correlations between GDP per capita and AESV of Chongqing were weakened according to spatial autocorrelation, which is manifested as “integrated high and low values took the main part, with dual high values and dual low values as auxiliary parts”, of which low-high clustering regions were distributed in northeastern and southeastern parts and high-high clustering regions were distributed in western parts and main city zone of Chongqing. Finally, decision-making references and suggestions would be put forward in this thesis to realize the dual growths on both economy and ecology in various districts and counties according to their local conditions in Chongqing.

This article analyzes the development process and characteristics of education urbanization and private education in Feidong County in 2005-2017, and explores the influence of private education on the county education urbanization process. The result shows that: （1)From 2005 to 2017, the urbanization level of compulsory education in Feidong County has been steadily improved, showing the time-series change characteristics of “slow-fast-slow”.(2）Feidong County’s private compulsory education has developed rapidly. The proportion of private compulsory education students increased from 2.2 percent in 2005 to 35.0 percent in 2015, higher than the national average. Private primary schools develop slowly, while private junior middle schools develop rapidly. The proportion of private junior middle school students in Feidong county once reached 74.2%, and more than 90% of private junior middle school students are enrolled in Chengguan Town of Feidong County. （3)Private junior middle schools continue to attract a large number of rural students to study by selecting sites in urban areas, introducing and improving the “Boarding system” and improving the quality of running schools and social reputation, which has significantly promoted the process of education urbanization in Feidong County.

This article analyzes the development process and characteristics of education urbanization and private education in Feidong County in 2005-2017, and explores the influence of private education on the county education urbanization process. The result shows that: （1)From 2005 to 2017, the urbanization level of compulsory education in Feidong County has been steadily improved, showing the time-series change characteristics of “slow-fast-slow”.(2）Feidong County’s private compulsory education has developed rapidly. The proportion of private compulsory education students increased from 2.2 percent in 2005 to 35.0 percent in 2015, higher than the national average. Private primary schools develop slowly, while private junior middle schools develop rapidly. The proportion of private junior middle school students in Feidong county once reached 74.2%, and more than 90% of private junior middle school students are enrolled in Chengguan Town of Feidong County. （3)Private junior middle schools continue to attract a large number of rural students to study by selecting sites in urban areas, introducing and improving the “Boarding system” and improving the quality of running schools and social reputation, which has significantly promoted the process of education urbanization in Feidong County.

Exploring the temporal-spatial evolution of suburban rural tourism destinations and its determinants of spatial distribution is conducive to guiding orderly rural tourism development in suburban area，the hot area of rural tourism development; and it is helpful for guiding suburban rural tourism development practice and rural-revitalization-strategy policy making. 534 rural tourism destinations within Wuhan City’s rural urban fringe were analyzed and classified, and the mathematical statistics and spatial analysis methods including the nearest neighbor index, kernel density estimation and Hotspot analysis were fully applied to study the temporal-spatial distribution features and its influencing factors. The conclusions are as follows: (1) Rural tourism development in suburban Wuhan has experienced four distinct development periods; and the distribution of rural destination hot spots and cold spots in Wuhan has been changing dynamically; now, three tourism agglomeration areas have been formed in the northwest, west and south of Wuhan. (2) The types of rural tourism destinations in Wuhan are increasingly diversified, from the original two types (sightseeing tourism destinations and cultural tourism destinations) to current five types (sightseeing tourism destinations, farming tourism destinations, agricultural technology tourism destinations, cultural tourism destinations, and special village and town), and there are differences in the development speed, scale and agglomeration of different types of rural tourist destinations. Thereinto, sightseeing tourism destinations have the largest development scale, with a significant trend of concentrated development, forming a multi-core development distribution pattern; and farming tourism destinations started later, but with the fastest development speed and the highest degree of concentration；meanwhile, special villages and towns also experience some agglomeration distribution with indistinct agglomeration evolution trend, and the radiation range of the polar core are always small；cultural tourism destinations gradually evolved from scattered distribution to a spatial pattern combining "great dispersion" and "small agglomeration"；agricultural technology tourism destinations have been in the state of dispersion rather than agglomeration.(3) Distance from the central urban area, policies factor, traffic conditions, the hydrological factors and quality of rural tourism attractions, all are determinants of the spatial and temporal distribution characteristics of rural tourist destinations with different impacts on the spatial and temporal distribution of different types of tourist destinations. This research ended with some suburban rural tourism development references and suggestions.

This paper takes the per capita tourism economy of 14 cities (states) in Hunan Province from 2000 to 2018 as the research object, and uses the Dagum Gini coefficient and its decomposition method to measure the regional differences of tourism economy in Hunan Province, and then uses the convergence theory to test the province and the four major tourism. The convergence characteristics of the circle. The results show that: (1) The spatial differences in per capita tourism income of the province and the four major tourism circles are prominent. The interregional disparity is the main source of Hunan’s tourism economic disparity. The intraregional disparity and the hypervariable density show a slow downward trend. The tourism differences are mainly concentrated in the two major tourism circles of Western Hunan Province and Chang-Zhu-Tan. (2) The province and the four major tourism circles not only have σ convergence, but also all have conditional β convergence. At the same time, there is also absolute β convergence in the province and the three tourism circles around Dong-Ting Lake, West Hunan, and South Hunan. (3) Regional economic development level, tourism resource endowment, fixed asset investment, urbanization rate, transportation accessibility and information development level have a strong influence on the convergence of the tourism economy of the province and the four major tourism circles.

Forecast of ecotourism demand in Hunan Province from the perspective of supply and demand is conducive to the optimal allocation of eco-tourism resources and the sustainable development of eco-tourism industry. In order to further understand the demand of eco-tourism market in Hunan Province, this study uses the relevant data of eco-tourism from 2008 to 2017 as sample data, and uses GM (1,1) prediction model, linear regression prediction model, nonparametric model, BP neural network prediction model and time series prediction model (2) to predict the demand of eco-tourism in Hunan Province, and obtains the highest simulation accuracy of linear regression model.Therefore, the linear regression model is used to predict the total ecological tourism revenue and the total number of ecological tourists in Hunan Province.The results show that the total ecological tourism revenue and total number of ecological tourists received in Hunan Province are in curve growth at medium-low speed: from 2021 to 2025, Top 5 cities and prefectures in total ecological tourism revenue are Changsha, Zhangjiajie, Yueyang, Changde, Xiangtan andYiyang ; Top5 cities and prefectures in the total number of ecological tourists received are Changsha, Changde, Hengyang, Chenzhou, Yiyang. Different cities and prefectures are unequal in total revenue and number of tourists, represented by Changde and Zhangjiajie.

Based on fisheries resources surveys conducted in the Panzhihua section of the Jinsha River from 2013 to 2017, variation characteristics of fish biodiversity before and after impoundment of the Guanyinyan Hydropower Station were statistically analyzed in present study. A total of 65 fish species belonging to 3 orders and 10 families were identified during the five-year study period, 20 of which were endemic to the upper reaches of the Yangtze River. Of the 65 fish species, 12 were detected in each year, all of which were lotic fishes except Pseudobagrus vachelli. Abundance/biomass comparison (ABC) curves and W statistics revealed that fish communities were seriously affected after impoundment and operation of Guanyinyan Hydropower Station in October 2014. Cluster analysis (CA) and non-metric multidimensional scaling analysis (NMDS) showed that fish species composition could be divided into two groups: Group I (2013-2014) and Group II (2015-2017), but one-way analysis of similarity (one-way ANOSIM) indicated no significant difference between the two groups. According to similarity percentage (SIMPER) analysis, species that decreased in abundance in group II were mainly those spawning drifting eggs such as Coreius guichenoti and Rhinogobio ventralis. Therefore, to better conserve natural fish resources in the Panzhihua section, a comprehensive strategy including on-site conservation, off-site preservation, ecological operation, artificial reproduction and releasing should be developed.

With the acceleration of urbanization, the original natural habitats and ecological processes in the Jiangnan water network area have been destroyed, the urban ecological security has been gradually lost due to the ribs and regional features, and the construction of a composite ecological network for regional ecological protection and sustainable development. It is of great significance. This study comprehensively considers biological processes, hydrological processes and human processes, builds habitat networks and recreation networks based on cumulative resistance models, constructs water-green networks using ArcGIS hydrological analysis, and builds an ecological network framework for multi-objective fusion through GIS spatial superposition to Jinzhou Jinzhou. The district explores the construction of a composite network for the case area. The results show that: (1) The source area of single-objective ecological network in the study area is water-green source area > ecological source area > recreational source area; the source area of double-objective ecological source area is water-green ecological source area > water-green recreational source area > Ecological Recreational source area, and the source area accounts for a small proportion in the total area, mainly distributed in Maoshan in the West and Changdang Lake in the south; (2) The triple-function corridors in the study area are mainly distributed between the central and Western Maoshan Mountains. In addition, a large number of ecological and water-green corridors are also distributed in the southwest; more recreational corridors are distributed in the northeast; (3) In the later period, we should strengthen the protection of the key ecological functional areas such as the western and southern areas where the source and corridor distribute more, while strengthening the protection of the eastern and Northern areas. (4) Through case studies, the construction of complex ecological network can connect relatively isolated landscape patches in the region, which is conducive to the protection of biodiversity, the improvement of urban ecological environment, the maintenance of regional landscape pattern, and the guidance of the rational development of regional space.

Fragmentation changes the structure and function of ecosystem and limits the value of it. The effect of different fragmentation factors and their relationship on ecosystem services need to be revealed. Taking Suzhou as a case, the spatial and temporal characteristics of ecosystem service value and fragmentation in different periods from 1995 to 2015 are explored based on the multi temporal remote sensing image data and the town unit scale. The role of fragmentation factors and their interaction effects on ecosystem service value are principally revealed with the help of GeoDetector method. The results show that: （1）The ecosystem service value tends to decrease in stability. The spatial distribution inclines to be relatively balanced from the polarization trend of high value and low value. （2）The fragmentation is strengthening gradually. The spatial distribution shows the evolution law of ‘mutual independence→agglomeration→high agglomeration→ agglomeration’. （3）The effect and explanation level of fragmentation factors on whole ecosystem services and its all types of services become weaker. Patch density and aggregation degree show strong and sustained forces in various services. （4）The interaction between factors is non-linear and linear, and the damage and protection effect will be more significant. （5）The synergism with other factors, the risk area and ecological differences of patch density is the strongest among the fragmentation index. It is the key and breakthrough point of protection and optimization. Key factors, action modes and risk identification can enrich mechanisms for ecosystem service value and provide a scientific reference for the further efficient protection of ecosystem.

Based on the data of land use change survey from 2005 to 2015, combined with land use change model and ecosystem service value theory, it analyzes the evolution law of land use structure and changes of ecosystem service of county units in Yangtze-Hwai Ecological Economic Zone, Jiangsu province. The results show that the area of construction land and water area increased most greatly during the study period; the land use degree index shows a spatial pattern of high north and low south. the ecosystem service value increases slightly, and it was higher in the southern than the northern part of the study area, and the pattern shows that the urban area is low and the surrounding counties are higher; during the study period, the contribution of water area to the ecosystem service value and the regulation of the ecological environment the ecological economic zone in Yangtze-Hwai area are significant; combined with the status quo of regional construction and development, the study area is divided into the following five types on the county scale by using the ecosystem service value sensitivity index: priority conservation area, priority development zone, balanced protection zone, balanced development zone, adjustment development zone. The construction and development strategy have also been proposed to guide the development, construction and environmental protection in the ecological economic zone in Yangtze-Hwai Ecological Economic Zone scientifically.

The grain size characteristics of sediments are very important for the analysis of wetland sedimentary environments and sediment transport trend. Based on the sediment samples of the Nanji wetland of Poyang Lake, this paper analyzes the composition, sedimentary type, dynamic environment and transport trend in the Nanji wetland using particle size analysis, Shepard triangle, C-M map, end member analysis and GSTA model. The results show that the sediments in the Nanji wetland are mainly fine silt, with an average percentage of 55.35%. The average particle size of the sediment is 5.24Φ, and the spatial distribution has a tendency of decrease from the southwest to the northeast. The types of sediments are mainly silt, clay silt, sandy silt and silty sand, of which silt accounts for 62.5%. The results of end member analysis show that EM1 and EM2 may be related to sediment transport caused by the lake current of Poyang Lake itself, EM3 indicates the source of sediment in Nanji wetland, and EM4 may be related to hydrodynamic changes of local environment. The pattern of the transport trend is most prominently from the east to the west and from the north to the south. The Nanji wetland formed by the complex interaction between the Ganjiang River and the Poyang Lake.

The twig functional traits and their variations of woody plants are important parameters reflecting the environmental adaptation of plants. The wild populations and cultivated populations of Pinus dabeshanensis, a rare and endangered plant, lived in different habitats for a long time, whether there are significant variations in twig functional traits remains unclear. In this study, two wild populations and two cultivated populations of P. dabeshanensis in Dabie Mountains in Yuexi and Jinzhai Counties in Anhui Province were selected as target, based on field investigation and sampling, the differences in twelve twig functional traits (including morphology, biomass and water content) and their covariant characteristics among different populations were comparably analyzed. The result showed that the variation coefficients of all twig functional traits ranged from 0.054 to 0.419, and wild populations generally presented higher values than cultivated populations. All twig functional traits showed obvious differences among different populations; thereinto, at twig level the stem diameter, stem area, branch number, diameter at breast height, needle length, stem biomass and twig biomass of cultivated young plants were the lowest in four populations, but they had the highest stem length and needle to stem biomass ratio. The cultivated adult plants represented the highest stem diameter, stem area and water contents of stems and needles. The wild population in Yuexi County had the lowest stem length while the other functional traits showed the middle size. The wild plants in Jinzhai County exhibited the highest needle length but the stem water content, needle biomass and needle to stem ratio were the lowest. The covariant characteristics of twig traits in different population of P. dabeshanensis were not all the same, but there were eight traits represented the same covariant tendency among different populations. Consequently, although the twig functional traits of P. dabeshanensis in different habitats had strong variability, their covariant relationship presented intraspecific conservatism to an extent.

Based on the socialization of peasants, the paper analyzes the main factors that may hinder small-scale farmers from responding to the external demands for low-carbon agriculture, and puts forward some proposals to promote lower-carbon agriculture. By analyzing the response characteristics of socializing household farmers to the lower-carbon agriculture orientation, a conceptual model is built based on the theory of planned behavior to analyze the path of socializing peasants’ lower-carbon management, and then two survey questionnaires were conducted in five districts of Tongshan, Huangpi, Ezhou, Jiangxia and Caidian of Hubei province. The surveys show that only a part of peasants have conducted lower-carbon managements mainly by reducing carbon emissions, and seldom can conduct lower-carbon management by increasing carbon sequestration. Further more some lower-carbon management behaviors may not be driven by lower-carbon willingness, which can be called unconscious lower-carbon behaviors. It means there is a  certain degree of deviation between lower-carbon willingness and lower-carbon behavior . The fitting results of the SEM model also verified the view. The conversion ability or probability of samples' lower-carbon intention to lower-carbon behavior is only 0.34, which is really limited because farmers think they may lack the ability to evade market risks and obtain considerable income. Besides samples’ original intention of lower-carbon management is to ensure their own food security and ecological environment security. The fitting results also show the factor of ‘subjective normative’ does not have sufficient impact on farmers' low-carbon behavior because the rules of collective action of peasant households are becoming less efficient under the socialization of peasants. Some proposals can be put forward to raise the conversion rate of lower-carbon intention to lower-carbon behavior and promote the transformation from the unconscious lower-carbon behaviors to conscious ones, including broadening socializing peasants’ cognizance of lower-carbon management, strengthening collective conscious by rebuilding farmers’ sense of belonging and mission to their hometown and reconstructing the spatial order of rural society, enhancing peasants’ perceived behavioral control ability to lower-carbon management by speeding up the transfer of farmland, cultivating new professional farmers, and promoting carbon sink trading.

The lack of market trust in the producer will lead to the serious shortage of green agricultural products supply and lead to the structural imbalance of food supply side. Based on 804 survey data of rice growers in Hubei province, the influences of market trust and institutional environment on the application behavior of biological pesticides of farmers were discussed. The results show：（1）Farmers not only lack trust in the consumption of agricultural products sold on the market, but also lack trust in the production of green agricultural products. 67.79% of the sample farmers are worried about the market sales of green agricultural products. （2）Market trust can significantly promote farmers’ application of biological pesticides. Compared with incentive, constraint system has a greater impact on farmers’ behavior, and market incentive and constraint system can effectively supplement farmers’ lack of market trust. （3）Governments and enterprises have different influences on farmers’ application of biological pesticides. Both enterprises and governments can significantly promote farmers’ application, but the effect of enterprises’ constraint on farmers’ green production is better than government. Therefore, it is extremely necessary to enhance farmers’ trust in the green agricultural product market, strengthen the construction of market institutional environment, and advocate multi-governance to make up for the limitation of government functions.

In order to strengthen the understanding of the internal logic of agricultural environmental policy from formulation to implementation, this article is based on the fairness perception and trust of farmers. This article constructed a theoretical framework for farmers’ to explain their agricultural environmental protection behavior under uncertainty. The data for farmers’ point of view was collected from Shanxi, Shandong and Shaanxi Province. The Path analysis, Bayesian nonlinear structural equation modelling, and Slope analysis methods were employed to test the hypothesis put forwarded in this article. The results showed that: (1) There were direct and indirect effects of farmers’ fairness perception on farmers’ behavior towards agricultural environmental policy. The impact of direct effect was much higher than the indirect effect. The direct effect indicated that the higher farmers’ perception of fairness was linked to highly motivate farmers to protect the agricultural environment. The indirect effect of farmers’ fairness perception showed that farmers’ fairness perception first enhanced the farmers’ trust, and then the trust in turn translated into the farmers’ agricultural environmental protection behavior. Likewise, (2) the uncertainty results of farmers’ agricultural environmental protection behavior had hindered farmers’ agricultural environmental protection behavior. Furthermore, the uncertainty results of farmers’ agricultural environmental protection behavior interfered with the transformation from farmers’ fairness perception to their behavior significantly. Based on the above results, it can be concluded that the farmers’ fairness perception and trust were important, and should be considered in agricultural environmental policy development. Therefore, previously used command-based agricultural environmental policies should be reconsidered. Similarly, the agricultural environmental policies which combined farmers’ participation should be implemented gradually as detecting the agricultural environment regularly and giving the feedback to farmers can be helpful to improve environmental conditions. Finally, this approach could not only reduce the uncertainty results of farmers’ agricultural environmental protection behavior and government regulatory costs but could also promote the effective implementation of agricultural environmental protection policies.

Pesticide pollution seriously threatens food safety and the environment of the production area. Paying attention to the choice of pesticide application by farmers is conducive to promoting the reduction of pesticides and green development of agriculture. Based on the field survey data of key tea areas in Shaanxi, Sichuan, Zhejiang and Anhui provinces, the Ordered Probit model was established to study the neighborhood effect and the acquisition of external technology and the adjustment of empirical capital based on the application of neighboring drug application information. Considering that there may be endogenous problems in the perception of pesticide utility, extended ordered probit estimates were also made using instrumental variables. The results are as follows. (1) The information transmission of neighboring pesticide application significantly promotes the increase of pesticide application rate by farmers, indicating that there is a neighborhood effect in the selection of pesticide application by farmers; (2) In the acquisition of external technology, the acquisition of enterprise application technology and the government application of pesticide technology have significantly promoted the reduction of farmer's application, but the regulation effect is not significant; (3) In the empirical capital, the record of pest and disease prevention significantly promotes the reduction of pesticide application by farmers, and the planting period significantly promotes the increase of pesticide application by farmers, but the regulation effect is not significant. Therefore, the government should cultivate the neighborhood information transmission mechanism to “degenerate the disadvantages into profits” through the village science and technology demonstration households, and drive other farmers to reduce the amount of application; at the same time, supplement the necessary technical training and special projects.

The city is an open and complex giant system. Flood disaster has direct or indirect impact on the natural, infrastructural, social and economic factors in the system. It is important to clarify the interactive relationships among the flood disaster and the urban system elements, and to evaluate and predict urban flood resilience, which contribute to the planning and construction of resilient cities. In this study, the simulation model of urban flood resilience was developed by analyzing the feedback relationships among flood disaster and urban system elements. Nanjing city was taken as an example. Four development scenarios were set to simulate the dynamic changes of flood resilience of Nanjing from 2009 to 2025. The results show that: (1) the urban flood resilience simulation model can reflect the interaction relationships among flood disaster and urban system elements, which can be used to predict urban flood resilience; (2) the greening coverage area of built-up areas and the design standard of rainwater pipe network in the urban system have significant influences on the urban flood resilience; (3) according to the existing urban development plan, the flood resilience in Nanjing will be continuously improved, which will be better than the continuous development scenario. However, there is still a certain gap with the typical resilient cities around world. Further improvements on urban greening, rainwater pipe network design standards, economic structure, and population quality should be taken to boost the flood resilience in Nanjing. The results of this study can provide theoretical and scientific support for the resilient urban development planning of Nanjing city and other cities.

In this paper, based on the daily precipitation dataset of grid points(0.5°×0.5°) of version 2 during 1961-2018 from China Meteorological Administration and NCEP/NCAR daily reanalysis dataset such as potential height, wind speed, specific humidity and so on, the percentile threshold method is adopted to confirm regional extreme precipitation events of Jiangnan area, and the comprehensive analysis of weather maps are extracted frontal and cyclonic extreme precipitation, and the temporal and spatial distribution and circulation evolution characteristics of those are compared. The results show that: (1) Frontal extreme precipitation is mainly distributed in the spring, while the cyclonic extreme precipitation is mainly distributed in the summer, and the frequency of frontal extreme precipitation is about three times of that of the cyclones.(2) Frontal extreme precipitation is mainly distributed in Wuyi mountain range, Nanling and other higher areas, while the cyclonic type is located in the southeastern coastal region, and places such as Fujian are greatly affected by both types of extreme precipitation.(3) From two days before the occurrence of frontal and cyclonic extreme precipitation to the same day of them, the vertical ascending velocity of airflow increases, and the subtropical high moves to the west. The maximum water vapor convergence center of frontal extreme precipitation dropped from the 850 hPa isobaric surface in Jiangnan area to the surface, while the center of cyclonic extreme precipitation moved from south to north to Jiangnan area. (4) The water vapor required by frontal extreme precipitation mainly comes from the western Pacific Ocean, Indian Ocean and bay of Bengal, and converges in Jiangnan, while the cyclonic water vapor mainly comes from the Indian Ocean, and moves westward with time in a vortex pattern.

Ten years after the Wenchuan earthquake, the types and qualities of ecosystem, community structures，pland biodiversity and soil nutrient recovery conditions were comprehensively assessed at the most severely affected areas. Through the Remote interpretation of ecosystem types, the sample survey of ground vegetation, the inversion of GPP and LAI, as well as the determination of the soil organic matter, total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus, and available potassium in the soil. The results exhibited that the regional ecological system generally tends to incline towards stability and positive recovery according to the remote sensing interpretations. Although the bare surface area assessed in 2017 was higher compared to the one before the earthquake in 2007, the decrease in number is relative to the post-earthquake one in 2008. In terms of ecosystem quality, the average values received from GPP and LAI continuously rose after 2014 though quite slowly. It reflected the overall resilience of the regional ecosystem. However, some of the forest ecosystems damaged by the earthquake still have not returned to the original state. A part of the farmland in the Chengdu Plain has been converted into an urban construction land. By 2017 in the earthquake-damaged area, there was a significant increase in the number of plant species, dominated by pioneer species, such as Rosaceae, Compositae, and Gramineae, similar results as to those in 2009. The community structure found at the earthquake-damaged area has been well restored. In terms of vertical stratification, the community structure of the remaining areas has formed three layers of trees-shrub-herb, noting that there is only one layer of herb or shrub and herb combination in the arid valley area. Generally, the soil fertility condition at the control spot was proved healthier compared to the impaired areas where the situation continued to deteriorate. The bare soil area that was caused by the earthquake has shown an acceleration in the mineralization process, increasing content of available nutritional elements in the impaired sites achieved short-term yet the loss of nutrients and soil fertility proved to be taxing long-term. Hence, there have been formulations of numerous suggestions: Based on strengthening the supervision of geological hazards and preventing secondary disasters, the natural vegetation must be dominated by natural restoration in the high precipitation areas of Western China, in front of Longmen Mountain. The arid valley area is able to adapt the appropriate artificial restoration measures which follow the principle of "adaptation to local conditions and matching trees with the site", Meanwhile, the improvement of soil nutrient conditions and the promotion of vegetation restoration must be given more emphasis and attention. In the process of urban construction, on the other hand, the land and space management and essential farmland protection must be strengthened, so as the red line of ecological protection, as well as all kinds of protected areas, including basic farmland.

As one of the important natural disasters faced by cities, urban floods have important impacts on urban social and economic development. For example, Beijing in 2012, Wuhan in 2016, and northern Anhui in 2018 suffered severe economic losses due to floods. This paper established the assessment index system of urban flood vulnerability based on the random forest model from nature, economy, and infrastructure aspects; then combined with the random forest and entropy weight method, the weights of the index system were calculated. Finally, the urban flood vulnerability assessment model (RF-VFS) based on the coupling of random forest (RF) and variable fuzzy set (VFS) was constructed. As a typical flood area in the middle and lower reaches of the Yangtze river basin, Nanjing city is prone to severe flood disasters in summer due to the influence of topography and seasonal rainfall. Therefore, Nanjing was taken as a case study area to explore the dynamic characteristics and driving factors of flood vulnerability, and the corresponding vulnerability grade curve of Nanjing from 1996 to 2018 is analyzed. The study handled data and its digital mapping based on GIS. The countermeasures were proposed from three aspects: urban flood management policies, urban infrastructure construction, and emergency measures for disaster prevention and reduction. The assessment results showed that indicators, such as accumulated rainfall during flood season, impervious surface area, GDP per square kilometer of land and urban road network density have significant positive correlation with flood. And the flood vulnerability level has been on the rise for the past 20 years, especially in the past 5 years, when the degree of vulnerability to flood has been relatively high. The results are consistent with the actual situation of flood vulnerability in Nanjing city. This study therefore provides decision-making recommendations for the relevant management departments to improve the flood management capability, and reduce the flood vulnerability.