Based on the uncertainty of the respond of water environment and resources on the background of global climate change，and aiming at the influence and potential risk on our water safety and water development and utilization of international rivers，that brought with complex nature environment and international relations on our southwestern border，this paper explored the potential risk of water disputes between our country and the four countries on the southwestern border，and used the “cloud model” to quantify and evaluate the qualitative human environment risk objectively. This study is to provide decisionmaking consultation for the development planning of the water resources in China’s southwest border and border conflict crisis disposal

The variation law of runoff has gained increasing attentions in hydrology and water resource research over the past decades,and is the key issue for sustainable use of regional water resources and water conservancy project.Exploration of the variation law of the flood seasons runoff in Zishui River Basin will provide an important theoretical reference in understanding the hydrological characteristics of the Zishui River and the sustainable use of regional water resources.River runoff changes also have some influence to flood and drought disasters of the river basin.Especially the frequency of flood and drought disasters in the southern,which occur in the flood season,is higher.As a typical representative of the southern river,Zishui,in recent years,shows an upward trend of flooding which brings great losses.Studying the variation law of the flood seasons runoff in Zishui River Basin also can provide a scientific basis for preventing flood and drought disasters.Based on monthly runoff data from 1990 to 2013 in the flood season of three representative stations in Zishui River Basin,including Luojiamiao,Lengshuijiang and Taojiang hydrological station,the intraannual changes of runoff in the flood season were analyzed by using nonuniformity coefficient and amplitude of variation; then application of these index values and flood and drought disasters in Hunan province has carried on grey correlation degree analysis; besides,the interannual changes of runoff in the flood season were studied by moving average and the MannKendall mutation test.The results are as follows. (1) During the flood season,the distribution of runoff was quite uneven in the Zishui River Basin,however,the runoff distribution tended to be even with the lapse of time.The monthly runoff showed a decreasing trend with fluctuation.As a whole,the indicators from the three stations presented a decreasing trend.(2) The grey correlation degree of runoff distribution characteristic index value during the flood season and river basins flood and drought disasters was extremely high.The characteristics of annual runoff distribution in the flood season of Zishui River Basin could better reflect the current years flood and drought disasters.The larger the value of the four indicators which reflect the uneven distribution during the flood season was,the more often flood and drought disasters would happen.(3) The distribution of interannual flood seasons runoff of Zishui River Basin was quite uneven,too.At first,it showed an increasing trend,then it fell,and it rose finally.However,in general,it presented a trend of decreasing.(4) Luojiamiao station,Lengshuijiang station and Taojiang station broke through the 95% confidence interval in 2007-2013,1990-1991 and 2010-2013,1990-1991 and 2004-2013,during these annual times the flood seasons runoff showed a trend of a significant reduction.Luojiamiao station and Lengshuijiang station appeared mutational sites in 2009 and 2010.For Taojiang station,UF statistics did not intersect with UB statistics and there have been no mutational site.

Based on the topographic maps of Nandashan,Xinhekou,Guozhenshi,Xinqiang and Taolinsi with a scale of 1:50 000 in 1955 and 1983, digital elevation models in these regions were setup by using Geographic Information System (GIS) tools  to vector contour lines and terrain points.And then the spatial distribution maps of surface vertical deformation were produced by calculating digital elevation models in two periods.Combined with distribution maps of surface vertical deformation,geological data and sediment deposition data,reasons of surface vertical deformation were analyzed.The results were as follows.(1)The subsidence areas were larger than uplift areas in NandashanXinhekou region during 1955-1983.Subsidence areas were mainly affected by the tectonic subsidence,while uplift areas were mainly influenced by sedimentation and human activities in the region.(2) In GuozhenshiXinqiangTaolinsi region,uplift areas were much larger than subsidence areas.Subsidence areas were mainly distributed along waters resulted from flowing water and human activities,and uplift areas were mainly influenced by the uplift of Mufu Mountain in the region.(3) The center of the basin was influenced by tectonic subsidence such as NandashanXinhekou region,most areas gave priority to the subsidence,but local areas were affected by water,sediment deposition and human activities,so that some areas were in serious subsidence,and some areas were uplift.And the edge region of the basin were influenced by tectonic uplift such as GuozhenshiXinqiangTaolinsi region,so most areas gave priority to the uplift,but local areas were affected by the constant flow of water,sediment deposition and human activities,so that some areas were increasedly uplifted,and some areas were kept in the state of subsidence.Therefore，studying the spatial distribution and related reasons of surface vertical deformation in the east of Dongting Basin will play an important role in understanding the evolutionary tendency and planning and construction of industry and agriculture.

We use a Gauss filter,EOF analysis,synthetic analysis,correlation analysis and other methods to analyze the characteristics of moisture transport in summer over the Tibetan Plateau in recent 50 years based on the NCEP/NCAR mean daily and monthly reanalysis data.The results showed that moisture transport in summer over the Tibetan Plateau in the layers had its own uniqueness.Moisture transport of the South China Sea and the eastern region of the Tibetan Plateau had an important impact on China mainland highaltitude water vapor,the water vapor of the Southern China and the middle and lower reaches of the Yangtze River on high altitude from the South China Sea area and the water vapor of the North China and the middle east of China on high altitude from East Central Plateau.The mean circulation transport and moisture transport had the same characteristics approximately.The longitudinal of transient eddy transport was very strong on the Tibetan Plateau,which was much stronger than its zonal transport.The mean circulation transport was one magnitude larger than transient eddy transport.The mean circulation transport influenced mainly moisture content of the eastern and southwestern regions in China,while the transient eddy transport influenced the north of China.The EOF analysis of the moisture transport showed that,EOF1 reflected the characteristics of the northwest wind transport that before about 1976 were positive anomaly,but weakened significantly after 1976.EOF2 reflected the characteristics of southwest wind transport that after about 1980 were positive anomaly,while weakened at other times

Based on American landsat ETM remote sensing data and so on, this paper constructed remote sensing demonstration system of 3D visualization based on Skyline digital earth model. Based on ERDAS, ARCGIS, MAPGIS and so on software platforms, it extracted remote sensing information of landscape and city expansion in the Yangtze River basin, regarding the environmental science and the theory of sustainable development as guidance, and combining with the basin flood disaster and the longterm goal of social economic sustainable development, this paper proposed the new ideas and countermeasures of land development and flood control under the condition of geomorphologic constraint in the Yangtze River basin. The results show that adopting the remote sensing three level classification of causecause formationphysical formation, and mastered the main landform types, structure and distribution characteristics of the Yangtze River basin; The basic landform units were fenced and the total number was 16 770; The landform was dominated by the mountainous region, hills and plateau types, in which the area of plain accounting a small share about 3.6×105km2; The geomorphic units of block, zonality and directional arrange with outstanding character, its material composition was complex and variable, so it was the important constraint factor of land development and protection; This paper found that there was a 36km long valley terrain latitudinally between Futou Lake of Jiayu city and Wang Lake of Yangxin County in Hubei through the remote sensing stereo system; So, we would accommodate this valley, constructing the large floodway between Futou Lake and Wang Lake through the Yangtze River; Its full length would be 139 km, and it would be 152 km shorter than the 291 km around Wuhan Yangtze River bend at present; So, this paper put forward a proposal which was along the hills and crossing over the down land, carving much more slots, building wall cautiously, keeping away the floodway and no migration, making a requisition of land and compensation in equilibrium and settling down in the neighborhood, land regulation and ecological agriculture depending on each other, considering the irrigation, shipping and tourism synthetically; Through the construction of the Yangtze River floodway and implementation of small and miniature store water project, it could realize the ultimate goal of flood radical solution, and its social, economic and ecological significance would be inestimable; The red layer which is suitable for water and dry farming , the karst basin and granite hilly landform with the weathered eluvium distributed widely, and agricultural development potential was great, so the land bottleneck problem of city construction in the Yangtze River economic belt would not exist in the future

Changes in landscape composition demonstrated apparent spatial variations in urbanization process.Consequently,hotspots were formed in the landscape locations with relatively rapid changing rates.Settlement growth hotspots were the most active location of landscape changes in the process of urbanization.The main aim of this study was to explore the influencing factors of landscape change hotspots.We used the Landsat TM images in 2003,2006 and 2011,spatial analysis and neighborhood analysis techniques to extract the settlement growth hotspots in Nanjing,Jiangsu Province at three observation scales of 13 km.Logistic regression was used to identify the landscape factors that influence the formation of settlement growth hotspots.The results showed that the spatial pattern of settlement growth hotspots varied significantly by study period,presenting the trend from a scattered to a relatively aggregated pattern.The analysis of land use composition in the hotspot and nonhotspot areas at the outset of the study periods showed that settlement growth hotspots tended to occur in the locations with relatively high cover of cropland and low cover of settlement within,while the opposite land use composition in the neighborhood.The presence of hotspots could be together affected by land use,landscape location and socioeconomic conditions,with obvious scaledependent features.Also,such hotspots took into formation in proximity of builtup urban areas and main roads,with relatively high cover of cropland and settlement,high per capita GDP,and low population density.The factor of nearest distant to main mountains and to the Yangtze River played exactly opposite role in different period of urbanization.To reveal the pattern of the landscape hotspots， its dominant factors had essential theoretical and practical significance for urban planning guide.Our results could have important implications on better understandings of urbanization,and decision making in land management practices

The land use status of Nanjing City was investigated by using the crossdata of land, capital and labor in 2009. The C2R model and Data envelopment analysis (DEA) approach were used to quantitatively analyze and evaluate the intensive land use efficiency of Nanjing City in 2012.The results show that intensive land use efficiency of Nanjing has not reached the summit level. In nonDEA efficient area, the land input was sufficient while the land output was not. The scale return of city areas has reached the optimal value while the suburb areas have not. For the structure return of most areas has not reached the optimal value, the land use structure should be optimized to increase the land use intension. While the efficiency of capital input was high, the efficiency of intensive land use was insufficient

With the number of nature reserves increasing and the protected area expanding,China's nature reserves also have many problems.Zonation unreasonable is one among them.Zonation largely determines the developing direction and management framework of nature reserves.It plays a vital role for the effective management of nature reserves.However,China pursued rescue protection strategies in a fairly long period of time.Inadequate theory,inappropriate zoning methods,lack of basic information brought  potential problems to nature reserves zoning.Now many nature reserves have reduction in biodiversity,community conflicts and other problems.Therefore,the use of scientific methods on nature reserve zoning is particularly necessary.Through data collection,field surveys,expert consultations,literature research,with the remote sensing and geographic information technology,using landscape ecology sourcesink system theory,this paper conducted functional zoning to Yaoluoping Nature Reserve.In landscape ecology,the “source” and “sink” are for ecological processes,the “source” refers to the landscape which can promote the development of ecological processes; “sink” landscapes are those that can prevent,delay the development of ecological processes landscape types.In accordance with the idea of biosphere reserves,zoning is a collar structure which from the inside to the outside can be divided into core zone,buffer zone and experimental zone.Species have least resistance to overcome in the core region,maximum resistance in experimental zone,and the resistance in buffer zone between the two.This paper selected the locations in Yaoluoping where protected species and endemic species widely distributed as “source”,selected the type of vegetation,vegetation cover,slope,terrain ruggedness as resistance layer of costs distance,used minimum cumulative resistance model (MCR) to create resistance surface,then graded the surface resistance layer with natural breakpoint method,ultimately determined the functional zoning Nature Reserve.Comparing the proposed zoning program and the existing zoning,the core area and buffer area expanded,the proportion rose to 38.46% and 29% from 17.2% and 23.9%,respectively; the experimental area ratio decreased from 58.9% to 32.54%; human activityintensive areas should be included in the experimental areas,which was conducive to strict partition management.For the future development of Yaoluoping Nature Reserve,this paper presented six recommendations including strict control of the scale of ecotourism,guiding the community's economic restructuring,strengthening ecological construction corridor,conducting publicity and education.These methods could be applied and extended to the related nature reserves

Based on the 70 surface soil samples with content of heavy metals measured,combining multivariate statistical and geostatistical methods,the distribution characteristics and sources of soil heavy metal contents in Huainan mining area were analyzed.Analysis results indicated that average content of soil heavy metals Cd,Cr,Cu,Ni,Pb and Hg of the study area were 0114,72406,26563,2988,25633,0039 mg/kg respectively,which did not exceed the national soil environmental quality primary standards,and the average contents of Cd and Pb exceeded the Huainan soil background values.Part of the samples of each heavy metal exceeded the national soil environmental quality primary standards and Huainan soil background values,and Cd,Hg and Pb were relatively obvious with the exceeding times of 43,241 and 0565 respectively.Correlation analysis and factor analysis showed that the sources of exceeding part for each heavy metal could be divided into two categories,Cr,Cu and Ni as one class,Pb,Cb and Hg as the other class.Analysis of the spatial distribution of heavy metals found that the exceeding part of the first category heavy metals were mainly located in the Pan three mine and the Xinzhuangzi mine,mainly because coal gangue was weathered and leached under the effects of precipitation,and heavy metals in Gangue internal were leached into the surrounding soil and water,and then the migration and enrichment were occurred,which finally caused serious heavy metal pollution.The exceeding part of the second category heavy metals were mainly located in the old urban of the Xinzhuangzi mine,which was caused mainly by the towns industrial production,transportation,pesticides usage and the city garbage

Ecological compensation is an important measure to ensure the ecological environment security of water source areas in the middle route of southtonorth water transfer project. After analyzing the temporary governmentled ecological compensation mechanism, this paper discusses the theoretical and practical basis of the marketoriented ecological compensation mechanism in the water source area of the middle route of southtonorth water transfer project. Then four patterns of the marketoriented ecological compensation are put forward. (1) Water rights transaction pattern. In this pattern, the market transaction mechanism and auction mechanism of water right are designed. (2) Development rights transference pattern. Development rights transference can be carried out mainly by industrial policy compensation. That is to say, water receiving areas acquire those companies that do much harm to the environment in the water source area, and help the water source area build enclaves in welldeveloped districts. (3) Ecological economy pattern. In this pattern, water source areas are encouraged to produce ecological products, and make full use of local characteristics to develop ecological economy. Thus they can achieve selfcompensation. (4) Public goods marketization purchase pattern. With compensated funds, governments buy ecological construction projections and services supplied by private sectors directly for water source areas, instead of producing by themselves and allocating funds to water source areas. At last, the paper comes up with some advice on how to gradually introduce the market force into the existing governmentled ecological compensation mechanism in the water source of the middle route of southtonorth water transfer project

Water quality assessment is the basis of knowing of the water quality status,which plays an important role in the management of regional water environment.In this study,surface water samples were collected from Lake Taihu and its main tributary in evenwater period.Grey clustering method was applied to evaluate regional water quality based on physical indicators (transparency,dissolved oxygen),nutrients (total nitrogen,total phosphorus,ammonia nitrogen),chlorophyll a and permanganate index.Multivariate statistical method was used to analyze and identify pollution factors.The results showed that the overall water quality of Lake Taihu and its main tributaries were in inferior status and the concentrations of pollutants  in most of the sampling sites (63% of the river water and 36% of the lake water in Autumn,2012 and 100% of the river water and 64% of the lake water in Spring,2013) exceeded the established water quality standards (Ⅲ).The results indicated that pollutants from the input rivers contributed a lot to the algal bloom in Lake Taihu in spring.Hence,more consideration should be taken to manage the water input from the inflouv rivers before algal bloom in Lake Taihu.To help better manage water environment,the sampling sites were classified into high,middle and low standards.Principal component analysis showed that nitrogen and phosphorus were still the main factors that affected water quality in Taihu watershed

Lake Taihu is a large shallow lake of the Yangtze River,one of China's five largest freshwater lakes.Since 1980s,the trophic state of Lake Taihu changed from oligotrophic to meso/eutrophic conditions due to humaninduced pressures.Crustacean zooplankton has long been used as an indicator of lake trophic level,which plays an extremely important role in water ecosystems.Sensitivity and adaptability to different environments vary from species to species,which lead to different response patterns.It has important application value to detect the water environmental quality evaluation effectively.In this paper,redundancy analysis (RDA) was employed to study the relationships between crustacean zooplankton community structure and temporalspatial variations of water environmental factors in Meiliang and Gonghu Bay in Lake Taihu from November,2004 to October,2005.The results showed that temporalspatial differences existed in nutrient concentrations between Meiliang and Gonghu Bay.It had relatively higher nitrogen concentrations in lake water in winter and spring,while higher phosphorus concentrations in summer and autumn.The trophic levels were significantly higher in Meiliang Bay than in Gonghu Bay,due to different nutrient inputs from the surrounding rivers.Nineteen species (12 species of cladocerans,7 species of copepods) of crustacean zooplankton were identified.There were no significant differences in species composition,and Bosmina spp.was the first dominant species of crustaceans in Meiliang and Gonghu Bay.Temporalspatial differences of crustacean zooplankton also existed in Meiliang and Gonghu Bay.In spring,the dominant species were large body crustaceans such as Daphnia spp.,while small individuals such as Bosmina and copepod larvae dominated in summer.Temporalspatial variations and community structure of crustacean zooplankton were mainly affected by temperature,chlorophylla and nutrient concentrations in lake waters.Correlation analysis indicated positive relationships between total biomass and density of crustacean zooplankton and temperature,chlorophylla and nutrient concentrations.RDA analysis suggested that different species showed different response characteristics to aquatic environmental factors

There were few reports on the relationship between algae density and chemical indexes of water quality. The monitoring on Dianchi Lake in summer of 2012 showed that the most relative indexes pairs were TNalgae density（r=0779 4）>TNcyanophyta density（r=0752 5）>TPalgae density（r=0701 8）>TPcyanophyta density（r=06609）>soluble TNcyanophyta density（r=0567 2）>soluble TNalgae density（r=0546 1）>soluble TNcyanophyta percentage（r=0535 1）, among the 30 pairs of relationship multiplied by 6 biological indexes and 5 chemical indexes. According to the above results, the most relative indexes pairs between chemical indexes and biological indexes were firstly TN, secondly TP, and thirdly soluble TN

The Hongfeng Lake is the important resource of drinking water in Guiyang city. The water quality has been improving since 2007 under the centralized management, which achieved the anticipated goal basically. In this paper, we will pay more attention to the study of 10year variation trend of water quality from 2003 to 2012 and the monthly variation tendency in 2013 by monitoring the water quality of seven sections and four tributaries in the Hongfeng Lake. Meanwhile, we also analyze the reasons for such changes in water quality. The result shows that the water quality in the Hongfeng Lake worsen sharply from 2003 to 2007, from Ⅲ drop to bad Ⅴ. Then, the water quality changes up to the present Ⅲ, local Ⅱ after sixyear centralized management. However, influenced by intrinsic pollution and domestic pollution, it still existed excessive TP, NH3N, COD in part of the sections, so the water quality was in nutritional status in the whole. For another, water quality of lake changed obviously in different seasons. It appeared mild eutrophication in June and July affected by rainfall and temperature, but the rest of the month are in nutritional state. Besides, water quality of branches in the Hongfeng Lake was polluted to varying degrees, contamination level improved significantly till 2011, but four tributaries were still polluted by life pollution, mainly for excessive BOD5, fecal coliform bacteria and so on. According to these comparative experiments, the processing facilities need to be taken into account and the further management should be strengthened to deal with the pollutant source so as to achieve the requirements of water quality

After impounding, water environment of reservoirs has been significantly changed due to dramatically increased water level, lower flow velocity, poorer diffusion ability and longer retention time in the tributaries. This change can lead to eutrophication which is more likely to occur in tributary than in main stream. Longchuan River, one of the branches of Wudongde Reservoir in Jinsha River, is the major water source to supply drinking and irrigating for Chuxiong City. The change of water dynamic condition in Longchuan River could result in eutrophication after Wudongde Reservoir impounding. A twodimensional, laterally averaged hydrodynamic and waterquality model, CEQUALW2 was taken to perform simulations and predictions of eutrophication in Longchuan Rivers backwater area. The simulation parameters included water temperature, total nitrogen (TN), total phosphorus (TP), flow velocity and chlorophylla (Chla). The simulation results were as follows: firstly, when the operation water levels were high in April, August and September, the Chla concentrations were high and reached 64mg/m3 over 60% distance along the river, so higher risk of eutrophication existed. The lowest risk happened from May to July because of higher flow velocity, and December to February because of lower water temperature. The second, main factors that limited the algae growth were flow velocity and water temperature when the nutrient saline levels were high. For instance, there were obvious stratification and slow velocity in the surface of section near estuary in April and August, so Chla concentrations in the rivers mouth were 70 times and 140 times higher than the sub reservoir tail. The third, there were significant intrusions from Wudongde Reservoir to Longchuan Bay with three forms of intrusion to the surface, middle and bottom respectively.The unique flow characteristic provided a hydrodynamic background of nutrient distributions of Longchuan Bay. Moreover, the densitystratified flow in different direction along depth could decrease the flow velocity of surface water and enhance the capacity of heat storage at certain time, which provided favorable hydrodynamics and temperature for the algae growth in tributary. In addition, the model was also used to evaluate the effects of change of reservoir operation and reduction of nutrient load on algae biomass of branch reach. The modeling results of the four conditions (decreasing water level to 950m in April, cutting TP and TN concentrations of branch into two different nutrient levels, cutting nutrient of branch and main stream synchronously) indicated that decreasing water level and cutting nutrient could improve the water quality of branch and restrict the eutrophication of branch effectively. However, only cutting nutrient concentration of branch was not enough, cutting nutrient of branch and main stream synchronously was more effective. Therefore decreasing water level and “double cutting nutrient” can be taken to restrict the eutrophication in reservoir when great risk for eutrophication existed, and can be used to control algae bloom in the branch of similar ChannelType reservoirs

In order to know the effects of salinity chronic stress on feeding, growth and biochemical composition of juvenile mullet (Mugil cephalus), the tame mullet juveniles (Mugil cephalus) were cultured at water salinity 20, 15, 10, 5 and 0 for 20 d, respectively, with feeding rate, special growth rate (SGR) in body weight and body length, RNA/DNA value and the biochemical composition of muscle determined on the 0th d, 5th d, 10th d, 15th d and 20th d. To facilitate the presentation, S20 was used to stand for the experiment group with the salinity 20, the same as S15, S10, S5, S0. The results revealed that the feeding rates were highly salinitydependent (P < 005) at the beginning of the experiment. Low salinity had an obvious inhibitory effect on the feeding rates of juvenile mullets. Compared with the beginning, the feeding rates had a great advance at the end of the experiment (20th d). The feeding rates of juvenile mullets in S0, S5 were increased from 567%, 579% to 1290%, 1299%. The SGR in body weight and body length were also sensitive to the changes of salinity of water. At the beginning of this experiment, the SGR in body weight and body length were quite different among different salinity groups. The SGR in higher groups such as S20, S15 were higher than in lower groups (S5, S0) (P<005). The SGR of juvenile mullets under the same salinity increased as the experiment went on. The gap between various salinity groups also gradually became narrow. At the end of the experiment, the SGR in lower salinity groups became very close to the higher salinity groups (P>005). The test results of RNA/DNA value also revealed that at first the juvenile mullets grew better when they lived in high salinity water, and then the gap became smaller among these experimental groups, which were consistent with the above rules. The biochemical composition of juvenile mullets was significantly affected by low salinity stress (P <005). The testing results of juvenile mullets muscle showed that the mullets body had a highly content of moisture which accounted for about 75% of the body weight. And the fat and protein contents were occupied about 9% and 6%, respectively. The ash content was the lowest in mullets muscle. The content of moisture in muscle increased with decreased salinity (P<005). At first, the water content in mullets muscle in lower salinity environment was higher than in higher salinity environment, with a ratio of 73% in S0 while 70% in S20. The ratios of moisture became bigger with the experiment, and the ratio in S0 even reached 78% at the end of the experiment. Though the salinity, too, had noticeable impact on the ratios of fat, protein and ash in mullets muscle (P<0.05), the change regulation of fat, protein and ash were quite different with the variation of moisture. The ratios that fat, protein and ash occupied in body weight of juvenile mullets increased with the decreased salinity and the increased test time.

Precipitation anomaly indexes of four seasons were calculated using precipitation data of Wuling Mountain area from 1960 to 2012, then the occurrence of drought events were rebuilt according to drought criterion. Based on this, the temporal and spatial distributions of drought at seasonal scale were analyzed. In spring, higher occurrence frequency of wild drought was appeared in most part of this area than in southeast area, and northwest area, north area and part of south area had the highest occurrence frequency, reaching 5082%. During summer, mild drought and moderate drought covered large range of highfrequency distribution. Mild drought appeared in most parts, western and northcentral regions had higher frequencies, up 5738%. Almost all part of this area had higher occurrence frequency of moderate drought than southwest area, especially in west, north and middle area, where peaked at 3771%. In autumn, the distribution of different levels of drought appeared significantly different characteristics. Higher occurrence frequency of mild drought appeared in westcentral area and south area, where peaked at 5410%; moderate drought largely concentrated in east and south area and south area had larger distribution of higher occurrence frequency, where peaked at 4098%; severe drought mostly happened in middle and south part of Wuling Mountain area and the occurrence frequency was up to 2787%; very severe drought mostly happened in middle and east part of this area. In winter, mild drought mostly happened in northcentral area where peaked at 5738%, and low occurrence frequency appeared in south area; moderate drought happened in most part of this area, together with higher occurrence frequency, which was up to 3934%; severe drought mostly happened in northeast area and part of south area, where peaked at 3115%; very severe drought had lower occurrence frequency, which mainly distributed in north and middle area. In addition, drought hazard degree index was constructed which was used to analyze the distribution of drought hazard at seasonal or annual scale. Conclusions at seasonal scale were drawn that spring and summer drought hazard degree were higher in north area than in other area, autumn drought hazard degree was higher in eastcentral area and winter drought hazard degree was higher in northeast and part of middle area. There was low drought hazard degree in the whole Wuling Mountain area at annual scale. On the basis of the above, correlation analysis between drought hazard degree of different seasons and topographic factors were conducted. The results showed that spring drought and summer drought were significantly correlated with elevation and there were no significant correlation between seasonal drought and slope or surface rolling. This study can provide a reference for the development of rational planning and the guidance of agricultural production in Wuling Mountain area

Based on the daily land surface meteorological data of Tongling weather station during 1980-2012, some climatic indices concerned with urban environment, such as plants growing season index, human comfort index, degreedays index and hazy days in Tongling are analyzed. In addition, the effect of area climate change on urban environment is also analyzed. Based on the analysis, some results can be drawn. Firstly, growing season length and human comfortable days are increasing, which indicates that the main environmental climatic conditions in Tongling area are becoming more and more fitting for human habitation in recently 33 years. Secondly, the cooling degree days index is in creasing while the heating degree days index and haze days are declining. It indicates that the energy consumption of Tongling area in the future summer will be further increasing, but the energy consumption for warming in winter will be expected to decline substantially. It will be helpful to improve the air quality. Thirdly, the correlation analysis suggests that the plants growing season index, cooling degree days and thermal uncomfortable days are significantly positively correlated with the annual mean temperature; while those of heating degree days, cold uncomfortable days and haze days are negatively correlated with the annual mean temperature. In short, the regional climate warming is helpful to improve the ecological environment of Tongling area

For past 20 years, rapid urbanization and industrialization in Wuxi, not only made a significant increase in builtup area and a rapid drop in arable land, but increased energy consumption, car ownership, and industrial emissions year by year. The characteristics of climate changes and their response to urbanization effects in Wuxi City during last nearly 60 years were analyzed, using the meteorological data of Wuxi from 1995 to 2012. The results showed that the average temperatures, maximum and minimum temperatures, and the extreme maximum and minimum temperatures all had significant upward tendency, and the high temperature days increased year by year, especially after 1980, while the low temperatures, diurnal temperatures and the average relative humidities all had a downward tendency. There were few changes in precipitation, but the rainfall was not in uniform distribution. The drizzle frequencies, the low cloud cover and the sunshine hours were all in downward trend. Urban Heat Island (UHI) was more significant throughout the year, especially in Winter. The urban temperatures were 03℃-08℃ higher than the regional average, but the temperatures of area around lake region and country were below the regional average of 0℃-08℃. There was an increase in haze days but not foggy days, the haze days were mostly more than 30 days and the foggy days in 10 days or so after 2003. Urbanization and industrialization caused the UHI effect and urban dirty island effect (UDI effect), changing the surface conditions, and then affected the spatial and temporal distribution of temperature, relative humidity, and rainfall, which led to an increase in haze days and decrease in foggy days

The research of vertical forest vegetation zonation is the frontier issue in global change. In the paper, a detailed analysis is made by using the automatic weather station and meteorological stations data. Based on factor analysis and Mann Whitney U test method, this paper extracts out the main climatic factors and discusses the climatic boundariess problem of vertical vegetation zonation in southwest mountainous areas of Zhejiang province by the comparison between 39 subtropical east Chinese mountains. The results show that the temperature, the climatic seasonality and the wind are the three most important climatic factors. There are significant correlations between winter strength and the boundaries of broadleaved forests and coniferous forests. The lowest average monthly temperatures between -0.8℃ and -1.2℃, between 2.1℃ and 2.9℃, are the lowest boundaries of deciduous broadleaf forest and evergreen deciduous broadleaf forest. The annual mean temperature between 13.3℃ and 13.6℃ is the boundary between warmconiferous forest and temperatureconiferous forest. Wind is one of climatic factors on limits of altitudinal forest belts, but we cant qualitativily delimit the climatic boundary now

 The Yangtze River Delta is in eastern neotectonic subsidence area This area lies in the lowlying areas， with tidal flats and wetlands widely distributed Future sea level rise will intensify storm surge， saltwater intrusion and other disasters， which will cause huge losses to the regions socioeconomic development In this study， scenario simulation and vulnerability assessment methods were applied to evaluate the vulnerability of estuarine and coastal areas in Shanghai and quantify threatened zones of 2030 and 2050 under sea level rise and storm surge disaster scenarios Based on the existing disaster prevention， the results showed that the most vulnerable areas against flooding were the lowlying areas along the Huangpu River The vulnerability index of Shanghai in 2030 would be relatively low， and vulnerable areas mainly concentrate in the junction of Fengxian and Nanhui， Changxing and Hengsha islands and lowlying areas along the Huangpu River At that time， 062 million of population would be exposed to above 05 m， about 186% of the total population， with 227 people died （at 50% confidence interval）， and the economic losses would be 1152 billion yuan， 1372 billion yuan， 1632 billion yuan （respectively under the scenarios of economic growth rates of 8%， 9%， 10%）， about 15% of the total gross domestic product （GDP） of this city In 2050， the fragility of Shanghai would sharply rise， with vulnerable area expanding to 3546% of the total area， and distributed extensively Similar to typhoon No 9 711， 748 million of population would be exposed to above 05 m， about 2166% of the total population， with 5 976 people died （at 50% confidence level）， and the economic losses would be as high as 10 5581 billion yuan， 15 1248 billion yuan， 21 5959 billion yuan （respectively under the scenarios of economic growth of 8%， 9%， 10%）， representing 296% of the citys total GDP.

 Based on daily observed precipitations and daily measured discharges at Beibei hydrological station during 1961-2010 in the Jialingjiang River basin， temporal and spatial changes of some typical extreme precipitation indices and hydrological indices were analyzed in this research， and the potential relationships between precipitations in different regions and hydrological process at the outlet controlling station were discussed The results showed that river discharges at Beibei hydrological station had very good relationships with regional precipitations in the Jialingjiang River basin， and the changing trends of typical extreme hydrological indices were similar to the corresponding extreme precipitation indices During 1961-2010， annual precipitations in the whole basin and annual discharges at Beibei hydrological station showed decreasing trends Under this background， the extreme precipitation indices and extreme hydrological indices， which represent rainstorm events and floods respectively， were mostly decreasing At the same time， the extreme precipitation indices and extreme hydrological indices， which represent drought events and low discharges respectively， showed a certain increasing trends， especially the precipitation index representing for days having no rain in one year increased significantly in recent decades

 This paper analyzed the data of continuous rain from 1971 to 2010 in Longnan， and the conclusions were as follows：continuous rain mainly occurred between May and October， but the highest occurrence frequencies of continuous rain were during the summer harvest and sowing period from May to July and the autumn harvest and sowing period from September to October， which were the most harmful disaster and caused the most serious damage on agriculture in mountain areas in Longnan Combined with data about population， farmland ratio， GDP of Wudu County， etc， by the utilizing ARCGIS software， the maps of the possibility of disasters were gained Then， by overlaying and uniting the background of weather disasters and the vulnerability of disaster bodies， and compartmentalizing the hazard grades， the hazard attributions for continuous rain disasters were achieved From the map， it was concluded that the risk grade of continuous rain disasters was highest in the highaltitude chilly and moist region in Kang County， the south of Liangdang County， Wudu and Wen County， which were the high risk regions The risk grade of continuous rain disasters was lowest in the lowaltitude region in Li County， Tanchang and Cheng County， and in the Bailong River， Baishui River， Xihan River Basin， which were the low risk regions The above research results were significant to plan the flood relief measures reasonable for the upper Yangtze River， to prevent geological hazard and soil erosion， to protect the environment， especially to guide the farmers in Longnan mountainous area to arrange agricultural production strictly and reasonably， which could prevent and relieve damage caused by continuous rain