Transport plays an important role in the process of socioeconomic development and the evolution of urban form.According to the calculating processes and assessment methods of transportation superiority degree in “The Technical Specification of Regional Division of Provincial Major Functional Zones”,we used three indicators,traffic network density,traffic trunk influence value and location superiority degree.As to administrative division data, we used latest geographic database and statistical data of 62 counties of Jiangsu Province.Finally, base on the technology of GIS, we got the features and causes of spatial pattern of transportation superiority degree in Jiangsu Province.
The results of the research showd that transportation superiority degree had a regional differentiation of “high in the south and low in the north” in Jiangsu Province.Transportation superiority degree appeared spatial autocorrelation.High value and low value areas were relatively assembled and mosaic distribution.Distribution of high value area was along the Shanganjing line and  the Yangtze River, while distribution of low value area was along the abandoned Yellow River, Hongze Lake and the coastal of Jiangsu.There was relatively close relationship between transportation superiority degree and the level of economic development at county level.The correlation coefficient reachesed 0798.Transportation superiority degree had a partial normal distribution statistically.12.1% of the area had outstanding transportation advantages and superior transport condition for socioeconomic development.In contrast,27% of the area had obvious disadvantages and inferior transport condition,and thus impeded local socioeconomic development.The remaining areas, about 68% of the total countries, had a little bit better or a little bit lower than average level of transportation superiority degree.
Based on the analysis above, we could recognize the spatial mechanism of transport infrastructure and better understand how to take advantage of the good features or avert the disadvantages of transport infrastructure in Jiangsu Province.Transportation superiority degree represents how important a regional location and condition influence to its economic development potentially.The higher transportation superiority degree is, the better development environment we have.With long time of development for transportation construction,transport network in Jiangsu  has been gradually improved, and correspondingly transportation superiority degree is higher.Especially,13 key cities have higher transportation superiority degree and play important roles in affecting the development of their surrounding areas.But there are still some problems, such as no sufficient connection between different types of transport, especially lacking direct railways to sea ports.The current development situation of railwayriver combined transportation and oceanrail transportation lags behind overall improvement of economic conditions.In some harbor cities, the eternal transportations of the cities have some conflicts with inside city traffic, such as Lianyungang, Nantong, Suzhou and Zhangjiagang.There are relatively weak economic connection between Shanghai and Subei.Transportation superiority degree will be reduced by these factors.
In conclusion, there is a sustained demand for Jiangsu Province to accelerate the construction of transport infrastructure and improve the level of modern transportation industry,in order to promote social economic activities and realize city modernization

The 3D framework(Density， Distance and Division)，which comes from the 2009 annual report of the World Bank，is introduced in this paper to explain the development of Wuhan City Region in China.We focus on the relation between 3D and productivity disparities in nonprimary sector，and establishes a set of indicators to reflect the three dimensions of density,distance and division and to comprehensively test the importance of 3D.This paper then employs the OLS model to empirically analyze Wuhan City Region.The result presents that the density has a significant role in determining these disparities.A role for distance is less significant and the role for division is insignificant.The results show that it is more important to increase density and shorten distance than to integrate the resources in the Wuhan City Region.These results have important policy implications both for the Wuhan City Region itself and others，which also provide a new vision to evaluate urban agglomeration in China.〖HJ1〗

With the hypothesis that carbon emission is proportional to energy consumption,this research calculated gross and per capita carbon emissions of 30 provinces in China from 1987 to 2010,and divided provincial carbon emissions into five types by using Kmeans clustering analysis.When provincial data curves of carbon emissions over past 20 years were drawn and analyzed,it is found that there was a dramatic change in the developing trend of carbon emissions around 2002.This phenomenon implicates that the data curve of carbon emissions before 2002 could not characterize the future trends.Therefore,data of carbon emissions from 2002 to 2010 were employed,based on the Logistic model,to forecast and analyze provincial carbon emissions from 2011 to 2020.Compared forecasted data with actual ones,the margin of error in all provinces surveyed was below 7%, except for Ningxia 1458%.The average forecast error of provincial carbon emissions except for Ningxia was 622%.This result implies the accuracy of the Logistic prediction model.

Agricultural development established with sustainable ecology, society, environment and resources is the core idea of agricultural sustainable development.Agricultural sustainable development in Hunan Province during 2001-2010 was assessed by setup of the level model of agricultural sustainable development and the entropy method.The results indicated that the overall process of agricultural sustainable development in Hunan Province was on the rise.However, the development of subsystems showed significant differences.Economical system developed the fastest, followed by the social and resource system, the environmental system was the last.Thus, the agricultural sustainable development in Hunan Province was discordant in general.In order to improve the whole sustainable development of agriculture in Hunan Province, it is necessary to take effective economic policies and controls to enhance the coordination of the entire system, based on all factors affecting sustainable development of subsystems and mutual influences among the factors.

Through investigating the practice of Hectares Farmland Project in Jing’an district,this paper defined the conception of comprehensive rural land readjustment scientifically,discussed social relations and social contradictions in comprehensive rural land readjustment by institutional arrangements,aiming to achieve urbanrural integration development.The results of study show that comprehensive rural land readjustment not only concerned those projects including landleveling,farmland irrigation construction,village renovation,roads repairing,but also cared about social relations and social contradictions in those projects.Comprehensive rural land readjustment was system engineering.It carried out a series of key engineering and system arrangement, aiming to concentrate four kinds of resources and to make four kinds of transition.The major engineering mainly included “Hectares Farmland Project”,increase or decrease hook of urbanrural construction land and agricultural land consolidation.Four kinds of resources concentration meant concentration of farmland,construction land,labor force,market and service;four kinds of transition meant the transition of resources mismatch pattern,traditional farming practices,rural inherent scattered model and previous urbanrural development path.The system arrangement mainly included diversified financing,fund management,reform of the household registration system,social security,training and employment,technical support,land property adjustment and supervision and management.Under the background of drawing up comprehensive rural land readjustment planning in China,it is an important theoretical and practical significance to explore scientific problems of comprehensive rural land readjustment

After the impoundment of the Three Gorges Reservoir,the water quality and quantity have been focused seriously.Baseflow separation is regarded as one of the most important and difficult issues in hydrology,so its separation results have great influence on many aspects,such as hydrological analysis and calculation,water resources management,etc.In order to find a reliable baseflow separation method,we chose flow datas in 2007~2009 provided by Xingshan hydrologic station of the Xiangxi River watershed in the Three Gorges Reservoir,used filtered smoothed minima method to have a baseflow separation,and made a comparison with digital filtering and the smoothed minima method.The results showed that the BFI of smoothed minima,digital filtering and filtered smoothed minima were 042,039 and 036,respectively.The results that dealed with filtered smoothed minima were the most smooth,and corresponded with actual converge physical process.Filtered smoothed minima was able to have a better performance for tracing the digital filter method during ascension period and the smoothed minima method during the recession,required only one pass filtering in the forward direction instead of three pass(forwardbackwardforward)in the digital filtering.Therefore,it is the best separation method among this three baseflow separation methods

Current water resource management is facing more dynamic and complex difficulties caused by climate change and the rapid development.Adaptive management is considered as a new approach to successful water resources management.Facing increasing uncertainty,vulnerability assessment is an important initial process of adaptive management.This paper studied the vulnerability of water resources adaptive system，a societyeconomicsecology compound system,from the perspective of systems science,in order to find possible adaptive measures.Firstly,this paper defined water resources adaptive system,and explaind the definition of its vulnerability.Then a PressureStateResponse model (PSR model) was introduced for vulnerability analysis.Base on the PSR model,this article designed a vulnerability assessment index system of water resources adaptive system,which included pressure,sensibility and adaptability dimensions.At last based on entropy method and set pair analysis,we evaluated vulnerability of the Poyang Lake Basin by using data from 2001 to 2010.It indicated that vulnerability change trend was influenced by the change of pressure,sensibility and adaptability.During 10 years,vulnerability of the Poyang Lake Basin experienced a first increasing then slowly declining trend,and overall vulnerability index was below the medium level.Pressure index of water resources adaptive system fluctuated in decades,and mainly kept at a medium level in the Poyang Lake Basin.Major system pressures were caused by precipitation change,nature disasters,large amounts of energy consummation and pollution resulted from rapid economic development.As an important agriculture region of China,the Poyang Lake Basin had a large agricultural population;economic and social were sensitive to climate changes in accord with the sensibility index trend.Since 2001,adaptability had improved greatly,attributed to the economic development,scientific and technological advance,environment protection and ecological management.During the decades the increase of pressure and sensibility had a negative influence of system vulnerability.Fortunately,the amelioration of adaptability had a significant effect on reducing vulnerability of water resources adaptive system to climate changes and social changes.According to predicts,in the future with the rising temperature in the Poyang Lake River Basin,the ecological environment probably has the trend of degradation,agricultural production will be affected.At the same time,with economic development,the pressure from increasing energy consumption and water resources demand will further exacerbate the vulnerability of water resources adaptive system.Since the significant position of the Poyang Lake Basin to national ecological security strategy,adaptive measures should be take to ameliorate development mode and environment,improve the ability to respond to climate change and the capacity for sustainable development.To reduce the system vulnerability,four types adaptive measures could be adopted to increase adaptability.Those adaptive measures include ameliorating water conservancy facilities and urban infrastructure,improving emergency response capability,adjusting economic development model,improving resources efficiency, enforcing propaganda of environmental protection,controlling soil erosion and pollution emission,increasing environmental protection budget,etc.〖HJ1〗〖HJ〗

With the objective of supporting and guiding conservation of Lake Gehu based on the survey data in 2010,a mass balanced model of the Gehu Lake ecosystem was constructed using Ecopath with Ecosim software.The analysis results indicated that there were seven trophic levels (TLs) in the studied ecosystem,with the trophic flows primarily occurred in the first four TLs and effective trophic levels of the compartments varied from 1 to 3691.Total system production was 1 97482 t/km2·year,and the total system throughput was 8 562544 t/km2·year.Connectance index (CI),system omnivore index (SOI),Finn’s cycled index (FCI) and Finn’s mean path length (FML) were 0219,0189,799 and 2841,respectively.Primary production/respiration,primary production/biomass were 2189 and 3509,respectively.Mean trophic level of the catch was 256.Dominant food chain included the grazing food chain beginning with detritus and the detritivorous food chain beginning with detritus.Compared current model with the model of 1986-1989,system throughput of Lake Gehu shrinked,with rstrategist increasing and Kstrategist decreasing in the system.According to Odum’s description of mature ecosystem,the Gehu lake ecosystem now is degrading from mature status

This study investigated the factors controlling the δ18O composition of the precipitation in Guilin.Daily precipitation samples for stable isotope analysis were collected in Guilin during 2010.The stable isotope (δD and δ18O) in precipitation displayed obvious spatial and temporal variation,and thus could be used for providing：(1)the best natural tracer for studying the hydrological cycle;(2)the ambient temperature and amount at time of precipitation;(3)the ground surface elevation;(4)the distance between precipitation event and its water vapor source region in the ocean;(5)water vapor source migration pathway.Empirical relations between isotope of precipitation and climate were used in numerous studied aimed to reconstructing past climate from various environmental archives.δD and δ18O in atmospheric precipitation were tested and analyzed,and the results showed:the values of δD distribution ranged from 2905‰ to 9627‰;δ18O values distribution ranged from -02‰ to -1296‰.The tested result of stable isotope showed significantly seasonal variability.The research results indicated that there was a significant relationship between δ18O values and the types of monsoon winds.δ18O values of the researched area were mainly affected by summer monsoon of east and southeast area in summer.During the transportation of atmospheric precipitation,the δD and δ18O in vapor caused by intense precipitation became more negative.Thus,δD and δ18O values of precipitation in summer were more negative excursion than that in winter.The Local Meteoric Water Line:δD=887δ18O+1549 was established by using the relationship between δD and δ18O.This result reflected climate character of Guilin:the warm and rainy.In addition,Deuterium Excess （d=δD-8δ18O）presented different characters during summer and winter.At the same time,the equation showed that in the researched area,the vapor source of atmospheric precipitation were mainly from ocean of low latitude in summer,while in winter the vapor source of atmospheric precipitation were mainly from the evaparation of inland and part areas and the transportation of winter monsoon(westerlies).In 2010,the δ18O value of atmospheric precipitation in September was more negative than that in June.This result indicated summer monsoon was extremely strong in September.But the total precipitation in September was far less than that in June.The reason might be that summer wind was strong and caused atmospheric precipitation zone reached to monsoon marginal zone.All of this contributed to the relatively decrease of atmospheric precipitation in the researched area.This study provides significant information to understand presentday seasonality of precipitation and its isotopic composition in Guilin,and strong scientific basis for constructing environment temperature with the use of stalagmites and dripping water

With the development of social economy, the contradiction between resources development and environment protection in Yancheng coastal wetlands is becoming increasingly conspicuous.And the material composition and spatial pattern of this coastal wetlands have changed apparently.Therefore,structure optimization has become an important part of wetland study.Based on the goal of maximizing of the economic and ecological benefits,this paper adopted a model calling multiobjective programming，to build a series of constraints from the two aspects of social economic and ecological environment,in order to study the landscape structure optimization in Yancheng coastal wetlands.The result showed that the cultivated area increased 17 211.80 hm2,taking as much as 696% of the total.It was the largest increase proportion,mainly because people reclaimed and developed the tidal flat for farm land utilization.Native vegetation area were enlarged by reclaiming shoals for reed and limiting the spreading of Spartina.Meantime,mud flats area declined by 25 804.73 hm2,of which percentage changed significantly to 1043%.Economic efficiency improved by an increase of 642 000 000 yuan,at the same time,ecological benefit increased which made the overall benefits enhanced significantly.Also the wetland landscape structure was optimized.〖

Lake Taihu is a large lake in the Yangtze Delta plain,on the border of Jiangsu and Zhejiang provinces Eastern China.In recent years,Lake Taihu has been plagued by pollution as a result of rapid economic growth in the surrounding region.LandUse and LandCover Change (LUCC) is of intriguing interest in international research.And a lot of researches show that land use and land management practices have a major impact on nature resources especially water.To explore water quality characteristics in response to land use change in basin is helpful to controll water pollution from the source.Two kinds of representative areas,one is urban area in Jiangsu province with high population density beside the north of Lake Taihu,the other is cultivated land and water conservation forest in Zhejiang province,were selected for study areas in Lake Taihu watershed.Different forms of nutrients,such as TN,DTN,PN,NH+4N,NO-3N,TP,DTP,PP,CODMn,were monthly monitored from June 2009 to May 2010.In order to explore typical characteristics of the river water pollution in the Taihu lake basin,the regional and seasonal multivariate analysis were used.The results showed as follows. (1) High concentration levels of TN in HX and XM was 623 mg/L and 608 mg/L.DTN,PN,NO-3N and NH+4N in HX were 471 mg/L,152 mg/L,231 mg/L and 171 mg/L  respectively.DTN,PN,NO-3N,NH+4N in XM were 297 mg/L,312 mg/L,168 mg/L,080 mg/L respectively.The concentrations was 033 mg/L and 011 mg/L for TP in HX and XM.DTP and PP in HX were 012 mg/L,021 mg/L respectively ,while DTP and PP in XM were 003 mg/L,009 mg/L respectively.The concentrations was 617 mg/L and 421 mg/L for CODMn in HX and XM.(2) Generally,water quality of the river Huishuikou (HS) was worse than that of Xiaomeigang`s (XM).DTN was the main nitrogen form in HS,while DTN and PN were two main nitrogen forms in XM.TN concentrations were high in both two study areas.Therefore,controlling of TN pollution was important in two rivers area.(3) Based on the Oneway multivariate analysis of variance between HS and XM,it was found that land use pattern,land watercycle model and proportion of water conservation forests in the two study areas were significantly different.There were significant difference of DTN,NH+4N,TP,DTP,PP,CODMn between this two study ares.(4) HS area displayed the strong point source pollution based on Seasonal Multivariate Analysis of water quality parameters and the Pearson Correlation Analysis between water pollution and rainfall.Meanwhile,the main pollutants in XM including TN,PN,NH+4N showed the characters of nonpoint source pollution.Finally,the methods of water pollution controlling were the most important to improving water quality.Because the sources of water pollution were different,a variety of pollution prevention and control measures were needed.Therefore,in order to mitigation eutrophication of Lake Taihu,point source pollution,such as industrial pollution source and domestic pollution source,should be controlled in HS,while nonpoint source pollution,especially agricultural nonpoint source pollution,should be controlled in XM.〖HJ1〗〖HJ〗

Based to the monthly monitoring data of monitoring points in the Dianchi lake and the Taihu lake,analysis of pollutions with lake water at the same time in different geographical situation was comparatively studied,and the correlation between water quality of surface water and biochemical characters of cyanobacterial biomass was assessed.The results revealed that the degree of eutrophication in the Dianchi Lake was higher than that of the Taihu Lake during monitoring.Water quality index in the Dianchi lake showed increasereduceincrease,and was highest in June.While the water quality index in the Taihu lake showed a rising trend monthly.The content of kjeldahl nitrogen,total phosphorous and the total nutrients (N+P2O5+K2O) of the Dianchi Lake cyanobacteria biomass was same as the Taihu Lake,but the C/N was higher than the Taihu Lake.The content of the heavy metal elements in the various samples levels were lower than the organic fertilizer industry standards (NY5252011) except for As and Cd.Correlation analysis showed that lead and chromium of cyanobacteria biomass had significant homology.In addition,the content of ammonium nitrogen in surface water could be used as the extent indicator of eutrophication

The Danjiangkou reservoir watershed is the source region of middle route of the SouthtoNorth Water Transfer Project.However,agricultural nonpoint source pollution is threatening the security of water environment in the watershed.Based on Geographic Information System (GIS) and Digital Elevation Model (DEM),the database of agricultural nonpoint source pollution for the reservoir watershed was established.According to the filed measured data,Soil and Water Assessment Tools (SWAT) were adjusted to analyze the temporalspatial distribution patterns of nonpoint source pollution load in the watershed.The agricultural nonpoint source pollution loads per unit area of major landuse types were also calculated.Results showed that there was a greater temporal difference in the output of agricultural nonpoint source pollution within the year in the watershed (p<001).The load of agricultural nonpoint source was strongly correlated with rainfall (rN=0896，rP=0920,p=001),sediment storage,ammonia nitrogen,total nitrogen and total phosphorus in the rainy period of June,July,August,accounted for 576%,64%,501%,508% and 473% of total year.The loss amount of soil nutrient such as nitrogen and phosphorus showed a great spatial variability in the watershed (p<001).Both farmland and bare land had a high contribution to the nonpoint source pollution load,whereas the contribution of forest to the pollution load was low.Its sediment load per unit area,nitrogen adsorption,dissolved nitrogen,phosphorus sorption and dissolved phosphorus were 715 t/hm2,892 kg/hm2,835 kg/hm2,807 kg/hm2,006 kg/hm2,respectively.This suggested that the agricultural nonpoint source pollution per unit area under different types of land use was obviously different.Under the simulated scenarios including different fertilizing amount and soil and water conservation measures,the reduction of fertilizing amount could effectively decline the pollution load of total nitrogen and total phosphorus,and returning farmland to forests or grasslands could notably reduce the output of sediment from farmland to river as well as the load of agricultural nonpoint source pollution in the watershed

A lot of studies have demonstrated that the NDVI and vegetation cover conditions showed a significant positive correlation,which could well reflect the status of vegetation cover.Thus,NDVI was subsequently used to study the changes in vegetation spatial and temporal dynamics.In this paper,we made use of the SPOT VEGETATION NDVI data between July and August from 1998 to 2011,computed two months NDVI average for each year,thereby generated the NDVI time series file of 14 years.We processed the NDVI time series file,extracted information and analyzed it,so as to reflect the vegetation growth conditions in Hubei Province as well as monitor and study the dynamic changes and trends of vegetation cover during vegetation growth peak in Hubei Province.The study area was divided into weak vegetation coverage area (NDVI value from 0 to 013),sparse vegetation cover area (NDVI value from 013 to 03),low vegetation cover area (NDVI value from 03 to 045),medium vegetation cover area (NDVI value from 045 to 06),high vegetation cover area (NDVI value from 06 to 075),dense vegetation cover area (NDVI value from 075 to 1) by vegetation cover partition method,to monitor the dynamic change of each vegetation cover areas during these 14 years.The results showed that with the exception of the dense vegetation cover area,vegetation area ratio in the other vegetation cover areas was basically stable,and the change extent was not great.They all increased firstly and then reduced,while the dense vegetation cover area showed decreased change in 1998 to 2002,and increased change from 2003 to 2011.Overall,the vegetation cover ratio of the study area had little change.After the analysis of vegetation cover dynamic change,we made use of the MannKendall trend analysis method to research on change trends of vegetation cover over 14 years.The results showed that the majority of the study area showed no significant change in trend,1655% of the region showed increasing trend,033% of the region showed decreasing trend.In order to analyze the influence factors of vegetation cover changes in Hubei Province,we collected the relevant statistic data about urban development,population and vegetation composition in Hubei Province from 1998 to 2011,researched on the relationship between the above factors and vegetation cover.The results showed that the urban sprawl,population growth and vegetation composition of the study area during these 14 years did not changed tremendously,so vegetation cover could be protected and vegetation cover was relatively stable.Through the above analysis,the study results based on vegetation cover areas method and the MannKendall trend analysis method were basically the same,indicating that the two methods could reflect the changes in vegetation cover from the vegetation cover status and trends angle dynamics.Besides,the two methods were an effective way to study temporal and spatial change of regional vegetation cover

In order to explore the indices and comprehensive evaluation of sensitivity to acid rain,six seedlings of subtropical species,including Myrica rubra,Cinnamomum camphora,Schima superba,Liquidambar formosana,Pinus elliottii and Metasequoia glyptostroboides were taken as test materials and exposed to simulated acid rain (SAR) with different pH values (pH 3.5,pH 2.5,and local reservoir water of pH 50-54 as the control).Gas exchange parameters,the chlorophyll content,membrane penetration and malondialdehyde content(MDA)were determined after treated for four months.The results showed SAR at pH 35 was unlikely to cause significant damage on gas exchange parameters and cell membrane,while pH 25 treatment altered gas exchange parameters significantly,net photosynthetic rate (pn),stomata conductance(gs),transpiration rate(Tr)and water use efficiency(WUE)were significantly declined.Compared with the controls,the membrane penetration and MDA contents in the seedling leaves under pH 25 treatment were increased significantly.The characters of seedlings behaved variously in their susceptibility to acid rain,therefore it was essential to apply more than one index to give a comprehensive evaluation on stress resistant.Principal component analysis could transfer many correlating indices into several independent comprehensive indices with little original information lost.Based on the test results,seven correlated single indices which had very close relationship with the acidic tolerance characters,were transferred into two independent comprehensive,with contribution ratio of accumulative total of 88.064%.Then,according to acidic tolerance coefficients and standardization eigenvector of seven respective charcters of each variety,two comprehensive indices scores could be calculated.The comprehensive evaluation value of each seedling acidic tolerance (D value) could be decuced by weighting sum the subordinative values and weight coefficient of the two comprehensive indices scores.The acidic tolerance of six subtropical species could be distinguished by hierachical cluster analysis,and M.rubra and P.elliottii were the strongest tolerance,followed by C.camphora,L.formosana,S.superba,and M.glyptostroboides was the weakest.The evaluation results accorded with their behavior in the field,which suggested the method could give an objective and precise evaluation on the sensitivity to acid rain between different species of seedlings

One of the key issues of river basin ecological compensation is the compensation standard. The opportunity cost is a problem in compensation standard.The opportunity cost has the character of uncertainty because of the specificity of ecological environment resources and the uncertainty of natural resources.The current opportunity cost accounting method didn’t consider the uncertainty of opportunity cost.The real option theory provided the methods to maximizing the value of project and getting the investment opportunity.The real option model of opportunity cost in river basin ecological compensation was set up based on the binomial expression realoption model.The Xi’anjiang basin example was applied for the model and tested the feasibility of the real option model.〖HJ1〗〖HJ〗

China is a mountainous country,and mountainous area counts for 2/3 of the total land area.Complicated geological and topographical conditions,climates with severe storms,dense population and human activities have led to frequent mountain floods and thus caused huge seismic casualty and property losses.Highway construction is essential to the development of mountainous regions in China,and highways in hilly areas are especially significant as key lifeline engineering.Thus we need to ensure highway traffic safe and unblocked. However,as a kind of ribbon engineering,highways in hilly areas are faced with conspicuous floods prevention and control problems due to its long distance and complicated conditions in topography,geology,climate and hydrology.Highway flood disasters refer to disasters that are caused by rainfall or floods and will lead to a series of geological damage to road infrastructure.Highway flood is a great threat to fluent traffic and it has also caused huge losses to road industry.According to the statistics,direct economic losses of highway and its accessory structures in China caused by mountain floods were as high as 4 450 million Yuan.Among them,regions stricken by mountain floods at different levels between May and July,2007,added up to 18 provinces (cities and districts).Traffic in 8 express highways,33 national roads and 578 provincial roads were interrupted and the economic losses reached 4110 million Yuan.National highway of G319 in Fuling District of Chongqing was researched in the paper,and it was divided into 340 zones according to the distribution of geomorphology and river system along the highway.With the support of ArcGIS,a risk assessment index system for highway flooding was established on the basis of floods developing environment,floods causing factors,floods suffering factors and flooding factors.And the index data for flood risk assessment of each zone along G319 highway were acquired through various methods.The comprehensive index of each zone was calculated in the risk assessment model,and then risk zoning was completed according to the thresholds of different levels.The results showed that medium risk was the main risk of G319 highway in Fuling District,which accounted for 6517% of the total length.Besides,zones with extremely high risk,high risk and low risk accounted for 076%,2310% and 1096% of G319 highway,respectively.Achievements in this paper will provide scientific references for the prevention and reduction of highway disasters, as well as safe and smooth transportation of highways.〖HJ1〗〖HJ〗

According to the monthly data of precipitation collected from 22 hydrographic stations of the Nanpan River basin in 31 years (1979-2009),taken standardized precipitation index（SPI）as the indicator and the period from November to the next March as the time period,the seasonal arid characteristics of the Nanpan River basin were analyzed based on the counted number of drought in recent 30 years in the time scale of five months.Moreover,the space distribution features of drought were analyzed through spatial interpolation by taking the average value of SPI in the time scale of five months from November to the next March as the indicator.The results indicated that SPI generally showed a downward trend during 30 years (1980-2009),and the meteorological drought was aggravated in annual variation;the drought became more serious in interannual variation since 1995.The meteorological drought happened across all areas to different degrees around the Nanpan River basin.In general,the degree of meteorological drought in the Nanpan River basin increased from the south to the north，and reached the worst degree in the northeast.The proportion of precipitation in the northeast was relatively small during November to the next March within one year.〖JP2〗The continuing drought from winter to spring was relatively serious in the Nanpan River basin so that the construction of water conservancy projects should be strengthened to control drought