Along with the rapid urbanization,periurban areas have emerged in the fringes of metropolis and some rural areas.Driven by the multiple forces coming from urbanization and industrialization,periurban areas are now transforming from rural society to complex ruralurban society.This paper takes the outskirts of Jiangyan as a typical periurban area to analyze the social and spatial changes under the background of rapid urbanization.The result shows that agriculture is losing its dominant position in both employment and income sources in periurban areas.Besides,periurban area becomes more urban in function and spatial structure,and the rural community form is in the shift from village settlements to urban communities.However,there are problems that exist in periurban area,such as the mixed and inefficient land use,the lack of infrastructure and public facilities,and the severe situation that residents facd in employment and social security.At last,we propose suggestions to ensure steady urbanization.

The research on the performance of a large sample agricultural land consolidation projects,has an important reference value for the scientific development of land consolidation policy.This paper employed the related data of 322 land consolidation projects with provincial investment from 2001 to 2009 in Hubei Province,constructed 13 indicators of land consolidation projects performance evaluation.By means of Delphi method and analytic hierarchy process (AHP),this study calculated the weight of each indicator,and sumed up the total value score of performance evaluation of each project;and analyzed the performance of projects and its spatial distribution characteristics,relation between performance of sample projects and investment per area,relation between the number of land consolidation projects and farmland resource.It is concluded that,the performance of major land consolidation projects was in general level,small percentage of land consolidation projects achieved good level,and achieved good economic,social,ecological benefits overall.Within certain criteria of investment,the correlation between investment per area and project performance was significant,the investment increase lead to performance increase.In response to the different engineering mode area,there was some gap of the average performance evaluation and total value around the cities,showing some regional differences.The projects number of each city had significant positive correlation with its area farmland resources,and it showed that land consolidation investment did not deviate from the policy direction to enhance grain production capacity of major grainproducing counties

Based on the multicenter network urban theory and cluster network structure competition theory,depended on the building of urban spatial network structure performance analysis framework and evaluation index,we used DEABCC model and DEAMalmquist index model to analyze the space network contact efficiency of 42 cities around the Poyang Lake during the year 2008 to the year 2010.The following conclusions are put forward in this paper.(1)Most cities around the Poyang Lake were in the spatial network contact of production frontier surface,and cities which were not in production frontier area are gradually moving to the production frontier surface by the comparison of efficiency.(2)From the efficiency decomposition,the change of the space network structure performance of cities around the Poyang Lake was affected by the technical efficiency and technical level transformation, and technical level had a visible effect on it.(3)On the distribution of efficiency of spatial difference,the spatial network structure performance of cities around the Poyang Lake presented the regular that performance of center zone is higher than that of the marginal zone,and performance of the marginal zone is better than that of the peripheral zone.However,the speed of urban space network development showed a regular that marginal zone has the fastest speed,followed by the center,and the peripheral zone has the slowest speed

It is a prerequisite to keep an optimal and efficient industrial structure and layout for regional socioeconomic development.In order to add a new perspective and new methods to the traditional paradigm of industrial structure and layout optimization based on economic and social indicators, such as regional resource endowments,industrial base,industrial competitiveness,etc,this paper put forward the concept and formula of industry environment quotient and regional environment quotient,and used it to optimize the industrial structure and spatial layout of ChengduChongqing Economic Zone.Starting from the mitigation of acid rain,based on the calculation results of industry environment quotient and regional environment quotient of various sectors SO2 emission,the industrial structure of ChengduChongqing Economic Zone was optimized. On this basis, taking the paper industry for example, combined with the cities SO2 emissions availability and their paper industry development status,the spatial layout of paper industry in ChengduChongqing Economic Zone was optimized

At present,the appropriate way to account the NOX emission about thermal power sector is the method of emission factor.In order to determine NOX emission factor of thermal power units in China,it is necessary to do actual measurement among existing running thermal power units all over the county.How to determine sample’s number and scope scientifically presents its special importance during NOX emission factor research,because China has a large number of thermal power units which are very different in installed capacity levels.Acute determination of sample capacity of thermal power units is the premise of NOX emission factor research.The statistical method sampling is needed.In this paper,group sampling is employed taking constraints into consideration,including funds,installed capacity scale,end control technology (NOX control),fuel type and unit regional distribution.Sample capacity is adjusted and optimized under the constraints,and at last sample capacity for NOX emission factor of thermal power sector in China is determined as 208 sets

As a means of transportation,highspeed railways affect urban space more and more deeply.Because of node,line,network and other characteristic,highspeed railways have corresponding impact on surrounding areas,cities,and the region at the regional scale level.According to the above thread,this paper reviews the existing literature,including theoretical and empirical study at home and abroad.We analyze land use layout and station reconstruction in the station level;focus on urbanization and the axis of agglomeration along the city level;pay attention to accessibility and regional integration linkage effect at the regional level.Based on the above comprehensive analysis,this paper proposes a basic analytical framework,and suggests a set of indicators to capture three major dimensions of the intertwining relations between highspeed railway and cities

Given the current concerns with water resources sustainable utilization under the background of socioeconomic rapid development,water resources threshold including its definition and meaning based on the natural and social characteristic of water resources is studied.According to the research,water resources threshold can be described with the coupling of water resources quantity threshold in natural system and its allocation ratio threshold in the socioeconomic system.Then given an example of Tai Lake Basin,the water resources threshold is calculated.The results show that the water resources quantity threshold of the Tai Lake is 1788×108 m3.According to the current economic development and its future plans in the target,the water resources threshold in the socioeconomic system is 1564×108 m3 under the restriction of natural ecology system water demand and water environmental capacity of the Tai Lake.The ratio of water resources threshold in the socioeconomic system is 531%, and the ratio in natural ecology system is 469%.It demonstrates that natural ecology system and the sustainable development idea of harmony between human and water are more focused in the Tai Lake.The ratio threshold of water resources allocation between different industries is domestic consumption 98%,primary industry 266%,secondary industry 582%,and tertiary industry 54% respectively,which provides profitable information for water resources sustainable development and utilization in the Tai Lake Basin

According to the population statistics data from 1990 to 2010,and based on the mathematical statistics analysis method and GIS spatial analysis method,this article analyzed the spatiotemporal pattern characters of population distribution in Wuhan Metropolitan Area.The result revealed that the population had a continued and steady growth.It could be divided as three periods,rapid growth period(from 1990 to 1999),stagflation growth period(from 1999 to 2006),and steady growth period(from 2006 to 2010).The population had distributed over the main highway sucn as YichangHuangshi Highway and HuangshiHuangmei Highway,and the tendency was constantly strengthened.The coefficient of variation of the population density was firstly increased and then decreased.The population distribution in Wuhan Metropolitan Area was firstly dispersed and then agglomerated,and the spatial heterogeneity which means the level of spatial difference was still obvious.The dynamic change of population distribution was circle spatial differentiation,and the population gravity centers were relatively stable.The main direction of population distribution was from northwest to southeast

Driving forces analysis is imperative in the study of landuse/cover changes (LUCC).We carried out a study on LUCC and its driving forces at village scale.Study pilots were 4 communities adjacent to the Gaoligongshan Nature Reserve in Nujiang River watershed of Northern Yunnan.SPOT5 remote sensing images combining with field investigation were used to classify land use types and create classification system.Land use patterns and characteristics at village scale were analyzed by using Fragstats 3.3.Meanwhile,socioeconomic data were obtained through household survey,semistructure interviewing,and questionnaires.Relationship between land use pattern and socioeconomic status was built to analyze driving forces of LUCC.Results showed that land use was driven mainly by natural conditions,villagers’ education level, and social customs.At the same time, households’ cash incomes depended strongly upon extensive land uses.Study results provide quantified information  for land resource management and village economic development in Nujiang River Watershed of Northern Yunnan. Methods we adopt can be used as a reference for LUCC studies at local scale

Health evaluation on land use system and diagnosis of its obstacle indicators would be greatly helpful for sustainable land use.On the basis of defining the meaning of health on land use system,the evaluation index system was constructed based on the PSR model,then an empirical analysis was conducted in Sichuan province by entropy method and obstacle degree model.The results showed that the health degree of land use system had been gradually improved from 2000 to 2008,with the index increasing from 0394 5 to 0557 3.The degree of land use system generally experienced two stages,i.e.,unhealthy and critical state.The pressure index overally showed a downward trend,while status index and response index a rise trend.In the long run,the system pressure was found to be the major factor affecting health on land use system.The obstacle degree of system pressure and system status increased by an annual average of 881% and 097%,respectively,but the obstacle degree of system response decreasesd by an annual average of 766%.The growth rate for fixed asset investment,per capita arable land,land reclamation rate,extent of soil erosion and per capita GDP were verified to be the key obstacle for further improvement of health on land use system.The health on land use system was continuously improved by further transformation of economic development mode,strengthening supervision and management for land utilization,increasing the intensity of environmental governance,effectively controlling soil erosion,and so on

Tree ring width is sensitive to the changes of climate in the cold or arid regions and less sensitive in the humid and warm climatic regions.However,some studies show that the tree ring δ13C of some species of trees in the humid and warm subtropical region of China is sensitive to the climate changes.Whether the Pinus massoniana Lamb ,as the widest distributed tree in the region,its δ13C is also sensitive to climate changes and to which climatic indicators,is still not clear.Two trees of Pinus massoniana Lamb on Mt.Zijin at Nanjing are selected and analyzed,in order to detect the sensitivity of its δ13C to climatic change.The relationship of the tree δ13C with the local temperature,precipitation,air humidity,and sunshine time,is analyzed.The results suggest that,the δ13C has closer correlation with the climatic indicators of the same year than that of the year before.The tree from the southwestern slop of the mountain has a higher value of δ13C,and the δ13C is better correlated with monthly mean lower or high temperature than from the southeastern slop.The pine tree δ13C is positively correlated with the monthly mean temperature,monthly mean high temperature and sunshine time,and negatively correlated with monthly mean lower temperature,precipitation,and air humidity

Based on the current condition of environmental data in China,this study developed a practical model for calculating watershed nonpoint sources load of heavy metals.The model integrates complex hydrology and sediment simulations (using the SWAT model) with simple export coefficient approaches.The model was applied to the cadmium pollution at the drainage area of the Xiangjian River in the Zhuzhou City,China.The uncertainty of the model simulations was also analyzed.The results showed that the total nonpoint sources load of cadmium at this area was about 2 435 kg/a,and the polluted soil was the major source which accounted for 657% of the total load.The nonpoint sources pollution was mainly controlled by the soil erosion process,and thus soil pollution prevention and conservation should be the key measures for controlling the nonpoint source pollution.The locations with highly polluted soil and/or those vulnerable to soil erosion (such as the Qingshuitang Industrial Park and its surrounding areas) were the critical zones for the pollution control,and April and May were the critical periods.The uncertainty analysis revealed that,with a probability of over 50%,the total nonpoint sources load was within the range of 2 000~3 000 kg/a,but there was still a possibility that the load was below 1 500 kg/a or over 4 000 kg/a

Through investigation of small towns in Chongqing,this study obtained the housing existing building enclosure types and thermal environment situation from Jan.to Sep.,2010,and used Chongqing area natural ventilation housing compatible model to evaluate indoor heat environment.Finally,this study found that the indoor lowest temperature was 83℃ in winter and the maximum relative humidity was 962%,while the indoor highest temperature was 344℃ in summer and the maximum relative humidity was 99%.In the natural ventilation conditions，only 2 days achieved the indoor comfort temperature in winter,while 58 days in summer.So it is more important to promote the heat preservation performance of dwellinghouse in winter than that in summer

Soil erodibility (the K factor in the Universal Soil Loss Equation,USLE) is an important index to measure soil susceptibility to water erosion,and an essential parameter needed for soil erosion evaluation and soil erosion prediction.Based on the second soil survey data,we established a database of soil properties of the upper reaches of the Yangtze River.We used cubic spline interpolation to convert the soil texture,the EPIC model to calculate the soil species erodibility, and the areaweighted method to obtain the erodibility values of subclass.After linking the K value of every soil subclass to the soil map,we got the spatial distribution characteristics of soil erodibility.The results showed that the mean value of soil erodibility was 0239 0,and the study area with lower erodibility,moderate erodibility and higher erodibility accounts for the main part,occupied 2796%，3261 % and 2720%，respectively.Soil erodibility of the Hengduan Mountains,the YunnanGuizhou Plateau and the Three Gorges Reservoir area was significantly higher than Sichuan Basin.High erodibility soils mainly located in the upper Jialing River and the valleys of the HengDuan Mountains.The average value was 0239 0,the maximum value was 041 and the minimum value was 007. K value had a certain regularity with soil erosion intensity,elevation gradient and slope gradient

Along with the discharge of nitrogen and phosphorus nutrient continuously into the lake,it led to water eutrophication,made the water transparency decrease,produce odor,which was harmful to human health.Through the use of appropriate evaluation model of water body eutrophication,we can evaluate the status of water pollution,and draw a correct conclusion.Then the appropriate treatment of eutrophic conditions can be taken timely,which will reduce hazards to the water environment and human health.In this paper,the fuzzy comprehensive evaluation method was applied,the hierarchy analytic process of the evaluation index was conducted.According to the the relationship of the index,the weight of each index was determined,then the mathematical model of fuzzy comprehensive evaluation was established.Finally according to the evaluation criteria and measurement of lake and reservoir water quality data,the typical lake and reservoir eutrophication assessment conclusion was attained.The evaluation results and the actual situation were consistent,and the model is suitable for wide application

Stimulated experiments were carried out to study nitrogen and phosphorus uptake and removal ability of 〖WTBX〗Pistia stratiotes〖WTBZ〗 L.in eutrophic waters.The results showed that 〖WTBX〗Pistia stratiotes〖WTBZ〗 L.grew normally in different degrees of eutrophic waters with initial concentrations of 245-941 mg/L TN and 044-153 mg/L TP.Accumulated 〖WTBX〗Pistia stratiotes〖WTBZ〗 L.fresh weight and dry weight increased to 16433-1934g and 857-1053 g for the period of study，the specific growth rate of fresh weight and dry weight were 044%-119%/d and 046%-14%/d，the ramet rate of 〖WTBX〗Pistia stratiotes〖WTBZ〗 L.was 133%-362%/d. The removal of nitrogen and phosphorus were 6920-31860 mg and 1560-6600 mg and nitrogen and phosphorus uptaken by 〖WTBX〗Pistia stratiotes〖WTBZ〗 L.were 352-20821 mg and 899-4837 mg，respectively.Meanwhile，accumulated assimilation of nitrogen and phosphorus increased with increasing initial nitrogen and phosphorus concentration in eutrophic waters.The removal contribution rate of nitrogen was 5326-6524% and that of phosphorus was 5958%-7419% in different degrees of eutrophic waters，respectively.Therefore，〖WTBX〗Pistia stratiotes〖WTBZ〗 L.had good removal efficiency，and planting 〖WTBX〗Pistia stratiotes〖WTBZ〗 L.in eutrophic waters could improve water quality

To further analyze the rain intensity characteristic and trend of the hourscale precipitation,we focus on the shortterm heavy precipitation events exceeding 98% fractile.Based on the onehour precipitation data of Anhui 16 meteorological stations from 1961 to 2009,several characteristics of shortterm heavy precipitation events were analyzed in this paper,including the shortterm heavy precipitation amount,frequency,intensity,the proportion of total precipitation and the trend of daily distribution.The results showed that there was an overall increasing trend of shortterm heavy precipitation in Anhui in recent 49 years,and the increasing trend was more significant in west than in east.The MK mutation test indicated that there was an upward mutation of shortterm heavy precipitation in 2001 and even more significant mutation after 2005,which were mainly caused by the increasing frequency of shortterm heavy precipitation.In recent 49 years,78% of the Anhui total precipitation increase was derived from shortterm heavy precipitation.Furthermore,the duration of shortterm heavy precipitation had increasing trend,but there was opposite trend in the duration of total precipitation.Consequently,the contribution of shortterm heavy precipitation grew greater to the total precipitation.Meanwhile,the daily distribution of shortterm heavy precipitation exhibited a significant bimodal structure,performing the peak during the after midnightmorning and afternoondusk period.The increasing trend of the shortterm heavy precipitation amount and frequency was more significant in the morning than that in the afternoonevening.Therefore,it could be speculated that the differences of peak and trough value would be reduced,with the characteristics of Twin Peaks gradually weaken in the future

Analysis on the distribution characteristics of precipitation in a year is of great importance for taking precautions against and fighting natural adversities as well as water resources management on the north slope of the Dabie Mountain.Using the daily precipitation data of 6 meteorological stations in Lu’an city from 1956 to 2010,the spatial and temporal distribution characteristics of annual precipitation concentration were analyzed based on the definitions of Precipitation Concentration Degree(PCD) and Precipitation Concentration Period(PCP).The results showed that the average PCD in Lu’an was 0.37 and the average PCP was the 37~38 pentad. The annual precipitation decreased gradually from southwest to northeast in spatial distribution,while the PCD and the PCP increased from south to north.The trend of annual precipitation was not obvious, but PCD and rainy season precipitation exhibited increasing tendency at the 010 significance level.It could lead to increasing risk of floods in rainy season in Lu’an city. The jumps in the annual precipitation occurred in 1972,1990 and an abrupt change occurred in 1972 in the PCD process.It is found that the annual amount of precipitation has significant positive correlation with PCD,that is to say the much(less) is the annual precipitation,the bigger (smaller) is the PCD.It is also found that when rainy season precipitation is extremely excessive and the PCD is much bigger than the average,Lu’an city is vulnerable to flood,otherwise to drought

In view of droughts development and evolvement of Hubei,Hunan,Jiangxi,Anhui,Jiangsu provinces along the MiddleLower Reaches of the Yangtze River in spring and summer 2011,based on MODIS images from April to August of 2011,normalized difference vegetation index(NDVI) from 16days synthetic data MOD13A2 was used to build and calculate anomaly vegetation condition index (AVCI),which had been divided into five levels to monitor droughts.8 phases of drought spatial distribution of the five provinces along the midlower reaches of the Yangtze River has been gotten based on anomaly vegetation condition index(AVCI),which showed the evolution process of droughts in spring and summer，2011.The results showed that the AVCI index could effectively monitor spring and summer droughts in the five provinces.During the entire monitoring period,AVCI of most parts in the five provinces was low and turned up widespread continuous drought.It was clear that the droughts had the trend of aggravatedreducedaggravated again from the sequence change maps of AVCI in these areas. Spring drought was mainly located in mideast of Hubei, midsouth of Anhui，southern Jiangsu，northeastern Hunan, northern Jiangxi,while summer drought was spread over a relatively large area in the five provinces.It was found that spring drought was heavier than summer drought,and drought was more serious in plain area

Based on the daily precipitation data of eight representative stations in the east of Sichuan Basin during 1961-2010,this paper analyzed the variation tendency of the annual and seasonal precipitation by using linear analysis and precipitation trend coefficient method.And this paper defined regional flooddrought indices with Zindex and studied the periodic rules on multitime scale by applying Mexican Hat wavelet transform method.The results indicated that annual precipitation had been lentamente declined in the area,but at the same time,the trends of seasonal precipitation was very different.The autumn precipitation was decreasing significantly,while there was an increasing trend in summer and winter.The flooddrought of four seasons had different annual and decadal time scale periodic variation characteristics,and different time scales had alternated on different cyclic rules.Approximate 6 years and 10 years periods in spring and autumn were found,and recently 6 years period was obvious.The summer had entered a waterlogging period on approximately 20 years scale period and the precipitation was not stable.Thus,high grade and serious flood disaster was easy to occur.And recently,autumn is in a approximately 10 years scale drought period and will turn to a partial flood period in the future