The urban agglomerations are important growth pole to lead and promote economy development in the middle Yangtze River Basin as well as Central China. By using social network analysis, we conducted a comparative analysis on spatial network structure's dynamic evolution of urban agglomerations in the middle Yangtze River Basin in 1990, 2000 and 2012. The findings of the study are shown as follows: (1) in 1990, Wuhan and Changsha were the two central cities in the middle Yangtze River Basin. The urban agglomerations' network structure has not yet been fully completed, which was a sparse network structure with the most cities falling outside the network. Taken Wuhan and Changsha as the centers respectively, it formed a linear relation structure constructed of the two small star-shaped cities groups. (2) In 2000, urban agglomerations' network structure became more complete. Wuhan metropolitan area and Changsha-Zhuzhou-Xiangtan urban agglomeration linked relatively close, and led by Nanchang, Poyang Lake urban agglomeration was merged in them actively. (3) In 2012, Nanchang became the central city. The spatial network structure of urban agglomerations in the middle Yangtze River has been changed obvious with Wuhan, Changsha, Nanchang as three urban centers. The network's heterogeneity of urban agglomerations reduced. The network was well-distributed and contact efficiency improved overall. The connection between cities became much tighter, more direct and mature. (4) The key factor to achieve regional development in the middle Yangtze River Basin is developing polycentric network structure and taking the combination development of urban agglomerations between inter-provincial, which should strengthen the direct communication between the urban agglomerations and construct urban agglomerations network by sharing the aim.

China has been stepping into a new spatial growing stage leaded by metropolitan areas, which results in new develop confusion of edge city due to the aggregation of metropolitan areas. In view of interaction among multiple metropolitan areas, this paper constructs the comprehensive model based on real economic linkage (flow, capital flow, information flow) and potential economic linkage between edge city and metropolitan areas, then defines the future development direction of edge city and puts forward related spatial development strategy. Huaian City, located among three metropolitan areas in Jiangsu, is taken as the case study region. The research result shows that: in recently, the absolute intensity of economic linkages between Huaian city and Nanjing, Suxichang, Xuzhou metropolitan areas are 1.688, 1.405, 1.164 respectively, accordingly, the subject are 39.65%, 33.01%, 27.34% respectively. The result indicates that the edge city doesn't belong to any metropolitan areas, the pattern of economic linkages of edge city is the result of economic radiation and spatial accessibility by the metropolitan areas. In the future, Huaian should make great effort to build key regional integrated network node, and stick to the development pattern of industrial dislocation, at the same time, make use of spillover effect and edge effect to build sub-Growth Pole. The study results can provide reference for edge city planning and development.

According to product categories, space at the township scale is composed of ecological space, agricultural space and construction space, which carry responsibility of socioeconomic development. Based on ecological constraints, it is a beneficial discussion under the strategy of ecological civilization adopting the concept of ecological protection restricting and supporting socioeconomic development to spatial function zoning. The index system, technical method and application of spatial function zoning should emphasize the coordination of ecology and development. Taking Xiongzhou Street at Luhe district of Nanjing as the study area, in this paper we analyzed ecological constraints, industrial development suitability and human settlements construction suitability based on single and comprehensive evaluation, using spatial analysis tools of ArcGIS and the exclusive matrix method. Result showed the overall layout of ecological space, agricultural space and construction space, in order to integrate and orientate of spatial function at the township scale. The district was divided into prohibited constructing area, limited constructing area, suitable construction area and constructed area, realizing the integration and scientific orientation for spatial function at the township scale. At the same time, our result provides the ecological environment protection measures and industry development orientation of the different area, which guides the progress of both regional development and ecological protection.

Under the background of that agricultural modernization has been vigorously promoted, the analysis of how farmland transfer influences the economic effect of farm households can provide the reference for the guarantee of farmers' rights and interests. A Bivariate Probit Model was set up to analyze the influencing factors of farmers' farmland transfer, and then according to the income and expenditure of peasant households, a Match Model was set up to estimate economic effect of peasant households. The results were as follows: Firstly, farmland transfer was significantly influenced by percentage, age, education level of the labor, the per capita share of farmland and the ecological environment of farmland of peasant households. Secondly, regional economic development and farmland large-scale operation were mutually improved and agricultural modernization was effectively promoted by their combination. Thirdly, the economic effect of peasant households was not decided by farmland transfer, the economic effect of peasant households can be improved only when the suitable mode of farmland transfer was chosen by farmers based on their own actual condition. We suggested to focus on improving the mechanism of farmland transfer market and rural social security system, achieving the orderly circulation of land management rights by using the power of market, and respecting farmers' willingness and guarantee the rights and interests of farmers.

Using the investigation data in Salangichthys tangkahkeii national aquatic germplasm reserve in Huaihong New River in June and December, 2014, we studied habitat characters and fish community. Most of the indices of water quality in the reserve could achieve water quality standard and TN was the restrictive factors. In the reserve, there were 24 species of aquatic vascular plants, including submerged plants, emergent aquatic plants, floating plants and floating leaved plants, accounted for 41.67%, 33.33%, 16.67% and 41.67%, respectively. In this investigation, thirty-seven species including thirty-three fish species and four shrimp species that belong to 8 orders, 15 families and 35 genus were collected. Because of the semi-closed habitat, the fish community was dominated by freshwater sedentary species and omnivorous species. Ecological dominance of fish community were analyzed through IRI indices, and Macrobrachium nipponensis, Cultrichthys erythropterus as well as Coilianasus were dominated species in summer, and Carassius auratus, Hypophthalmichthys molitrix as well as Hypophthalmichthys nobilis were dominated species in winter. The average weight of catch that collected from various kinds of nets ranged from 0.12 to 114.32 g in summer and ranged from 4.07 to 4.07 g in winter. Adult fish (shrimp) resources densities were 2.018×10⁵ ind./km² and 1.0441×10⁴ kg/km², and juvenile fish resources densities were 5.3458×10⁶ ind./km² and 587.8 kg/km². The fishery resources density in winter was significantly lower than in summer, and the result showed that resources quantity and weight density in winter only took up 6.94% and 30.93% of those in summer respectively. Indices of biodiversity of fish community based on individuals could be summarized as Margalef's index of 3.8120, Shannon-Wiener's index of 1.4960, Simpson's index of 0.4099 and Pielou's index of 0.1240. Furthermore, Procambaruslarkia was widely distributed in the reserve, more attention showed be paid to its strong invasive ability and the damage to the ecological system.

Based on the periodical fluctuations of water level, the standing vegetation in two consecutive flooding years was investigated by a space-for-time substitution method in the water-level-fluctuating zone in Three Gorges Reservoir Area. Niche breadth and niche overlap were calculated and were further used to analyze the changes of the plants species' niche breadth of the dominant herbaceous plants flooded for various periods. The results showed the niche breadth of the dominant plants before being flooded in the first flooding year was generally narrow and the niche breadth change was very significant. While in the second flooding year, the acclimatization of herbaceous plants to the moisture change increased. Before flooding, the number of species pairs with overlap value greater than 0.5 was only 125, and the number of species pairs with overlap value less than 0.2 was 189, among which, 103 species pairs' overlap values are 0. After flooding, the number of species pairs with overlap value bigger than 0.5 was 24, the number of those with overlap value less than 0.2 was 53, and 6 of the 53 species pairs had an overlap value of 0, which indicated survival of the species that can acclimate to the environmental change from dry to wet condition, resulting in an increased overlap value of the dominant plant species. At the areas flooded for 2 consecutive years, Digitaria chrysoblephara displayed the biggest niche breadth in the first year, and the rest 17 species, which occupy 61% of all the dominant species, showed the niche breadth less than 0.2. In the second year of the two consecutive flooding years, Pouzolzia zeylanica and Eclipta prostrata displayed comparatively big niche breadth, and the rest 15 species accounting for 50% amount of all the dominant species showed niche breadths less than 0.2. Only 8 herbaceous plants are the species that survived in the two consecutive years. Also in the second year of the two consecutive flooding years, there were 17 species pairs with niche overlap values over 0.5, while the number of species pairs with niche overlap values of 0 was 2, indicating that flooding in two consecutive years helped to form a more homogenous ecological habitant, and the number of species acclimating to similar environment increased.

As the major oil crop in China, rape has gained great significance in terms of the safety of cooking oil production. In this study, the temporal and spatial variation of rape cultivation in the Jianghan Plain, Hubei Province from 2002 to 2014 were investigated utilizing the MODIS NDVI time series data at 250 m resolution. The Empirical Mode Decomposition (EMD) method was used to derive endmembers of land cover types in the study area referring to auxiliary data including ground survey data and crop phenological data. Then, the Linear Spectral Mixture model was used to calculate area abundance in each pixel of decomposition. The spatial distribution of rape cultivation area in each year was then obtained. The results showed that the EMD method well filtered the noise of time series data as verified by yearbook statistics. The accuracy for extracted rape acreage was over 92.5% with R < sup>2 greater than 0.9. Furthermore, the spatial and temporal changes in the rape cultivated area indicated the overall positive growth and significantly effects of government policy and the variance of market price of rapeseed.

The Longmen Shan is located in the eastern margin of the Qinghai-Tibetan Plateau. The eastern margin of the Tibetan Plateau is composed of three large-scale geomorphic units: the Tibetan Plateau, the Longmen Shan mountain range and the piedmont alluvial plain (the Western Sichuan Basin) shown respectively from NW to SE. The Longmen Shan borders the eastern margin of Tibetan Plateau. It has a length of about 500km from NE to SW, and a width of about 30km from NW to SE. The difference in relief between the Longmen Shan and the piedmont region is greater than 4000m, with the peak elevation of the mountain range being about 4984m. The elevation of the piedmont ranges only between 450 and 710m. The Longmen Shan is the region with the maximum change in altitude on the edge of the Tibetan Plateau, comprising a series of roughly parallel imbricated thrust belts including the Maowen, Beichuan and Pengguan faults from NW to SE, and has the typical features of a progressive or onward-spread thrust-nappe structure. The Ms 8.0 Wenchuan earthquake of May 12, 2008, in the Longmen Shan mountain range area in China, led to two roughly parallel NE-trending thrust and strike-slip surface ruptures of the Beichuan, Pengguan and the Xiaoyudong faults. Thus, this area has been one of the best places to study the relationships about tectonic-geomorphy-water system. Stream-power incision model is often used to analyze whether the orogenic terrain has been to the equilibrium. This article presents the extraction and analysis of the 15 bedrock channel longitudinal section of the Longmen Shan. By using mathematical functions fitting with the morphological characteristics of longitudinal section, this article takes the relationship between bed rock channel slope (S) and the catchment area (A) to analyze the rivers in Longmen Shan in the eastern margin of the Qinghai-Tibet Plateau. The study has shown that there are 9 logarithmic function lines, 5 exponential function lines and 1 linearity line. The bilogarithmic graph (S-A Figure) of the rivers in Longmen Shan has 9 convex lines, 1 notching line and 5 straight lines, which has shown that the major bedrock river bed elevation of this area had been grown (dz/dt > 0), clined (dz/dt < 0) and unchanged (dz/dt=0) with time. The bilogarithmic graph (S-A Figure) of the south and middle parts at Longmen orogenic terrain is epirelief indicated that this area has not been to the equilibrium and it stays at pre-equilibrium. The bilogarithmic graph (S-A Figure)of the north part is straight indicated that this area has been to its equilibrium. Matching with the clear activity of the middle and south fracture parts at Longmen Shan tectonic zone, the results has shown the expanding to the east of Qinghai-Tibetan Plateau in time and space.

Chinese sturgeon (Acipenser sinensis) is a critically endangered species. Hydrological conditions, such as flow rate, water temperature, water quality, and streambed substrate have changed, and the habitats of Chinese sturgeon have been polluted due to the dam constructions. Changes of physiological and ecological behavior resulted from the environmental stresses have an important influence on the survival and growth of Chinese sturgeon. Juvenile Chinese sturgeon is one of the important groups for Chinese sturgeon resources supplement. Based on the literature, migration, feeding, swim behavior and the effects of environment pollution on the physiological and ecological behavior of juvenile Chinese sturgeon were reviewed in this paper, which will provide references to behavior research and protection of the Chinese sturgeon.

Sediment is the product of soil erosion, so it can reflect the characters of erosion process. In this study, six red soil samples, derived from three parent materials (Quaternary red clay, Shale and Granite) were selected and subjected to simulated rainfall experiment. The particle size distribution and cementing material of sediments were tested. From the compare of the physic-chemical properties of different sizes sediment, the main results as followed: Compared to the particle size distribution of test soils, there were more 0.002-0.02 mm particles in sediments, which occupied 26.68%-60.33% in sediments. It means that the runoff was preferred to transit particles between 0.002 mm to 0.02 mm. The proportion of 0.02-0.002 mm and < 0.002 mm particles were far greater than that in test soil from Shale and Granite while the proportion was lower than test soil from Quaternary red clay. After chemical dispersion treatment, the particle size distribution of sediment were different from the test soil, and there were more < 0.02 mm particles in sediments than test soils. The large particles (> 0.25 mm) in sediment from high-clay soils(derived from Quaternary red clay) is abundant, and most of which were stable aggregates. After chemical dispersion, there were more primary particles in sediments from high -sand soils (derived from Granite) and high-silt soils (derived from Shale) than in high-clay soils, and more clay and silt than test soils. The content of Fe_d, Al_d, Al_o and Si_o decreased with the increase of particles size in sediments derived from Granite, while Fe_d, Al_d and Al_o increased with the increase of particle size in sediments from Shale and Quaternary red clay. As a result, the large particles of sediments from Shale and Quaternary red clay were more stable than that from Granite. However, no obvious distribution regularities of Si_o were found in different size particles in three sediments.The content of organic matter also increased with the increase of particles size of sediment from shale and Quaternary red clay. However, the enrichment was not obvious for sediments from Granite, the content of organic matter of which was higher in 0.25-0.05 mm particles than in other sizes particles. The ration of MWD (mean weight diameter) before dispersion and after dispersion was positively correlated with the contents of oxide except Si_o, which was negatively correlated with the ration. It indicated that iron-aluminum oxides (Fe_d, Al_d and Al_o) are important stable factors of red soil aggregates.

The effects of global land use/land cover changes (LUCC) on the ecosystem and environment have been widely concerned, e.g. IGBP/BAHC,MBP,MA has paid more and more attention to the effects of LUCC on ecosystem hydrological cycle. Ecological water consumption, an important part of surface water cycle, has been the hot spots in ecological hydrology. Taihu Lake Basin has endured a rapid land use and land cover changes with rapid development of socio-economic in recent 25 years, leading to degraded ecosystem function of water volume regulation, e.g. watershed flooding disasters occurred frequently. Aiming to provide an eco-hydrological management mode for the Taihu Lake Basin, the impact of land use and land cover changes on ecological water consumption in Taihu Lake Basin in recent 25 years was assessed by computing the water consumption elements at grid units by means of GIS platform. The basic surface parameters which were used for water balance calculation were obtained by Remote Sensing and field monitoring methods. The main conclusions were drawn as followed: (1)the spatial distribution of total annual ecological water consumption and its components (interception and evapotranspiration) were in good accordance with distribution of vegetation cover. The areas of higher water consumption corresponded to a higher degree of vegetation cover, which distributed in the southwest mountainous and hilly areas in west Zhejiang Province, the northern and western hills around Taihu Lake. The areas of the lower water consumption corresponded to the areas of the lower vegetation coverage, which distributed in Pudong and Puxi district in eastern Taihu Lake Basin; large, medium and small cities, villages and towns in Suzhou-Wuxi-Changzhou region. Interception and evapotranspiration with high value distributed mainly in the hills and mountains with the forest, i.e. west Zhejiang province, north and west areas around Taihu Lake.(2)From 1985 to 2000 and from 2000 to 2010 in Taihu Lake Basin, the areas of a significant reduction in ecological water consumption were significantly larger than those areas of increasing. Areas of a significant reduction in ecological water consumption were distributed mainly over Pudong and Puxi district, Suzhou-Wuxi-Changzhou district and Hangzhou-Jiaxing-Huzhou district. Areas of increasing ecological water consumption were sporadic distribution during 1985 to 2000, and were mainly distributed in hilly areas west Taihu Lake Basin in 2010. (3)The annual ecological water consumptions, in 1985, 2000, and 2010 were 1068.83 mm, 1041.47 mm and 960.19 mm, respectively. The entire basin water consumption reduced, and reduced amplitude (2.53%) between 1985 and 2000 was smaller than that between 2000 and 2010(7.78%), consisting with the degree of cultivated land decreasing.

On the basis of the individual risk assessment, in this paper we study the maximum influence radius from the perspective of risk receptor when the accident of the urban internal risk source happened with the maximum likelihood. According to the spatial analysis of different types of risk source radii, the urban environmental risk zoning results were obtained through the comprehensive evaluation. We chose Nanjing as the research object. From the scope and degree of multi-type risk source inside the city, we analyzed the influence factors and radius in accident risk assessment including hundreds of hazardous chemical, hazardous waste, heavy metal pollution, high voltage corridor and natural gas highpressure pipeline, using the risk cartography to evaluate the urban accident risk. Considering the layout and city system we proposed the prevention measures and optimization suggestions. From the perspective of risk target we put forward the evaluation method and optimization recommendations. Our study will be important for the urban master planning, industry development planning and land use planning in the future of Nanjing city.

Understanding the formation mechanism of urban heat island (UHI) effect is crucial to study UHI mitigation strategies and other related urban ecological problems. Remote sensing images acquired on September 26, 1987 and September 17, 2013 in Wuhan were selected to derive land surface temperature (LST) values and detect the UHI effect. Mean LST and selected indices associated with UHI effect were calculated in each grid cells in the urbanized area. Principal component regression equations were modeled to find the key factors influencing LST distribution and UHI formation. Results indicated that: (1) high and sub-high temperatures built obvious heat "islands", covering 27.7% and 39.1% of Wuhan City in 1987 and 2013, respectively; (2) the key influencing factors on LST and UHI effect were impervious surface area index, percentage of water area, normalized difference built-up index, normalized difference vegetation index and percentage of green space; (3) as impervious surface area and percentage of water area increased at each 1%, LST value increased by 0.04-0.10 and decreased by 0.03, respectively.

Carbon Pool Management Index (CPMI) is deemed to be an important parameter to describe carbon cycle in soil ecosystem, and can reflect the change of carbon pool size well. By selecting 8 sampling plot of different forest types and a contrasted bare slop plot as study objects in the Lushan scenic area, the organic carbon pool characters and management indices were analyzed systematically. Some results were obtained as the follows. First, the soil organic carbon (SOC) was mainly distributed in the soil surface layer (0-20 cm). With the increase of soil depth, the SOC contents of the soil samples under various forest types all decrease sharply. In the depth of 0-60 cm, the average SOC contents increased in the following order: Pinus massoniana forest < evergreen broad-leaved forest < vegetation < coniferous and broad-leaved mixed forest < evergreen and deciduous mixed forest < Pinus taiwanensishayata forest < deciduous broad-leaved forest < bamboo forest. Moreover, the sequence of the average ASOC contents under different forest types and contrasted bare slop is deciduous broad-leaved forest < Pinus taiwanensishayata forest < evergreen and deciduous broad-leaved mixed forest < vegetation < coniferous and broad-leaved mixed forest < evergreen broad-leaved forest < bamboo forest < Pinus massoniana forest. The percentages of SOC under different forest types increase in the following order: deciduous broadleaved forest < Pinus taiwanensishayataforest < evergreen and deciduous broad-leaved mixed forest < bamboo forest < vegetation < coniferous and broad-leaved mixed forest < evergreen broad-leaved forest < Pinus massoniana forest. Furthermore, under various forest types, the ASOC contents are 0.24-0.57 g·kg^-1, and the TOC contents are 9.72-14.74 g·kg^-1. At the same time, the CPI contents are 1.63-2.48, and the A contents are 0.019-0.062, while the AI contents are 0.388-1.265. The CMPI under various forest types increase in the following order: deciduous broad-leaved forest < Pinus taiwanensishayataforest < evergreen and deciduous broad-leaved mixed forest < vegetation < coniferous and broad-leaved mixed forest < evergreen broad-leaved forest < bamboo forest < Pinus massoniana forest.

Field investigation, laboratory analysis and related methods were used to investigate the level of soil organic carbon (SOC) content, organic carbon and organic carbon storage and density distribution of the vegetation under seven different recovery modes in a small watershed of the Jinsha River. The results showed that significant differences exist between the different forest types and soil layers. in terms of the whole soil (0-100cm), SOC of the seven forest typesranged between the average content of 6.46±1.67-24.95±2.32 g·kg^-1, with an order of Cryptomeria fortunei forest > Alnus cremastogyne burk forest > Cupressus duclouxiana forest > Quercus variabilis forest > Acacia dealbata forest > Cupressus lusitanica forest > Cupressus torulosa forest, and the difference was significant (p < 0.05); SOC content of the soil in the 7 stands presented a table poly phenomenon, from the surface to the deep soil there was a decreasing trend, and with some regularity; seven kinds of soil bulk density increased gradually with the increase of soil depth on the whole, soil bulk density showed: Cryptomeria fortunei forest > Quercus variabilis forest > Acacia dealbata forest > Cupressus duclouxiana forest > Alnus cremastogyne burk forest > Cupressus lusitanica forest, Cupressus torulosa forest; consistent seven kinds of stands vertical distribution of soil organic carbon density and vertical distribution of soil organic carbon content characteristics, soil depth increases with soil organic carbon density reduced to topsoil 10 cm of soil organic carbon density maximu; organic carbon reserves were as soil depth percentage decreased, while soil organic carbon was mainly concentrated in the 0-40 cm soil, accounting for 65.60% of total organic carbon (Acacia dealbata forest), 63.16% (Alnus cremastogyne burk forest), 54.41% (Cupressus lusitanica forest), 58.56% (Cupressus duclouxiana forest), 62.96% (Cupressus torulosa forest), 61.70% (Quercus variabilis forest) and 56.37% (Cryptomeria fortunei forest),SOC of the 0-40 cm soil layer accounted for more than 50% of the total.

Surface net radiation is the main energy source which drives atmospheric movement. It determinates evapotranspiration,photosynthesis and the temperature of the Earth's surface and atmosphere, and plays an important role in the interactions between the surface and the atmosphere. This paper addresses the spatio-temporal variation of surface net radiationusing satellite-retrieved flux data over the Yangtze River Basin during 1983.7-2012.9. The data are composed of the surface radiation budget (SRB) and the Clouds and the Earth's Radiant Energy System (CERES) products. Statistical correlation analysis, Morlet wavelet analysis, Rodionovtime series analysis and GIS spatial analysis are applied. Our evaluation showed that the fittingsatellite-retrieved surface net radiationagreed well with meteorological observations, with an overestimation of 15.8%, with a mean error of 15.31 W/m², and a root mean square error of 21.58 W/m²(more than 99.99 percent confidence level). The accuracy of the fitting data meets the requirement of regional atmospheric research.From a spatial perspective, the maximum net radiation appeared at the western part of the Yangtze River Basin, followed by the eastern and the middle parts. The net radiationhad seasonal variations with a maximum in summer and a minimum in winter (a maximum value of 120.5 W/m² in July and a minimum value of 32.1 W/m² in December). The dominant inter-annual cycles include 16 and 10 year. From 1983.7 to 2012.9, the multi-year mean of surface net radiation was 78.0 W/m², and it had a decreasing trend with an abrupt decline in 1996. Net radiation d uring 1996-2012 is less than that during 1983-1995 in all the Yangtze River Basin, with more decrease in the upper reaches than in the middle and lower reaches of river basin. The reduction mainly happened from May to July, especially in June with a reduction of up to 20 W/m². The main regions with a large reduction of surface net radiation are the upper reaches and the low latitude regions of the middle and lower reaches of the Yangtze River Basin. Overall, the present study is valuable for understanding of the energy and water cycles in the Yangtze River Basin.

Based on the meteorological data of the 89 stations in East China from 1960 to 2014, using the climate tendency rate, IDW spatial interpolation method and standardized precipitation index (SPI), we analyzed the variation characteristics of droughts and floods and discussed the differences between north and south parts of Huaihe Rive from 1960 to 2014. The results show: (1) In recent 55 years, the precipitation in East China was gradually decreasing from south to north, for the area north to the Huaihe River, precipitation showed a downward trend, while precipitation in the area south to the Huaihe River was on the rise. (2) The frequencies of droughts and floods in South and North of East China showed a reverse trend. The influence range of drought in north of Huaihe expanded, the flood decreased, the area to the south of Huaihe River showed an opposite pattern. (3) The frequencies of droughts and floods in South and North of East China showed the reverse trend. The influence sphere of drought in the north of Huaihe was expanding, while the flood was falling, south of Huaihe showed the opposite trend. (4) The spatial distribution of frequency of severe drought and flood in East China appear north-south reverse pattern, which is the frequency of drought was high in north (south) of Huaihe, while the flood frequency showed an opposite pattern.

Heatwaves are significant environmental hazard which can cause increased deaths and emergency hospital admissions, particularly among vulnerable groups such as elderly people, young children and patients with chronic diseases. As the climate change continues, the frequency, intensity, duration and extent of heatwaves are likely to increase in the future. Under the control of the subtropics high in summer, the Jiangsu-Zhejiang-Shanghai Region, as one of the most advanced economic and most densely populated places, has become the frequent zone of summer heatwaves in our country. Based on the summer (from June to August) daily highest temperature data of 26 meteorological stations and the indexes chosen on the significantly increase in mortality, this paper conducted a statistical analysis on the temporal-spatial distribution characteristics of days, frequency and intensity of heatwaves in Jiangsu-Zhejiang-Shanghai Region from 1961 to 2010. The results show that Jiangsu-Zhejiang-Shanghai Region is a high-risk areaof heatwaves in our country, where the heatwaves weather exist significantly geographical differences. The high values of the heatwaves day numbers, frequency and intensity located in the middle and southwest of Jiangsu Province and west of Zhejiang Province. The tendencies of average heatwaves days frequency and intensity in Jiangsu-Zhejiang-Shanghai Region are very similar. Generally, the heatwaves days, frequency and intensity showed a trend of decrease (weaken) from the 1960s to the early 1980s, and showed a trend of increase (strengthen) from the late 1980s to the first decade of this century. Overall, the days, frequency and intensity of heatwaves in Jiangsu-Zhejiang-Shanghai Region have significantly increased and strengthened. Nearly 50 years, there showed the decline of the tendency coefficient for the heatwaves days, frequency and intensity in the middle of Jiangsu Province, which was the high-value region of the heatwaves, and showed rise of the tendency coefficient in the south of Jiangsu Province and east of Zhejiang Province, which was the low-value region of the heatwaves. So, the heatwaves weather in summer displayed a trend of gradually shifting to the south over the Jiangsu-Zhejiang-Shanghai Region. Heatwaves, affected by global warming and urban heat island, gradually intensified during the last 50a in Jiangsu- Zhejiang-Shanghai Region. The study followed should pay close attention to the heatwaves formation and change mechanism, such as the impaction of urban heat island and subtropics high on the temporal-spatial distribution of heatwaves.

In this study, based on the daily meteorological data of 84 meteorological stations in the Dongting Lake Basin from 1962 to 2013. we employed comprehensive Meteorological drought index (CI) to analyze the temporal and spatial distribution characteristics of meteorological drought in Dongting Lake Basin during recent 52 years. In the past 52 years, the result showed that the intensity of regional drought was mainly pronounced in summer, autumn, summer to autumn, autumn to winter. Among then, the regional drought intensity tended to increase in spring, summer, summer to autumn and winter. And it decreased from spring to summer, autumn, winter to spring. In addition, the regional drought intensity was unobvious in autumn to winter and annum. This pattern showed that different seasons had different trend of regional drought intensity, the seasonal variation trend was not consistent with the annual variation trend. The average drought intensity of continuous drought was heavier than that in a single season. The continuous drought contained drought from spring to summer, drought from summer to autumn, drought from autumn to winter and drought from winter to spring. Results from the Morlet wavelet analysis showed faster oscillation period of 4 to 6 years or 9 to 11 years on regional drought intensity, they alternated remarkably from drought to wetness. The period of 9 to 11 years was present throughout all studied time period, which was stable during this period. Based on the wavelet variance figure, the regional drought intensity had quasi-periodicity of 5 years, 10 years and 22 years. Among then, the 10 years was the obviously primary period, the 5 and 22 years were the secondary periods. In the past 52 years, the number of stations which had drought is relative fewer in spring. In summer, the range of drought stations ratio total stations in the basin was mostly presenting as local drought and part of the regional drought, and it showed smaller range in this season. The range of droughty stations ratio total stations was relatively higher in autumn, and it was similar with the droughty range of summer. Winter was a season that the value of droughty stations ratio total stations would be small. It was mainly represented as drought-free. In conclusion, the range of drought stations ratio total stations of four seasons in the basin was mostly floated from 10%-30%, presenting mainly as local drought and part of the regional drought. And the range of drought was generally wider in summer and autumn. High incidence of drought frequency mainly occurred in summer, summer to autumn and autumn, which located in the south mountainous area and northeast of Basin. Drought occurred less in the northwest of Basin, the frequency of drought converted from high to low in the HengShao Basin.

In order to investigate changes of extreme air temperature in Yunnan Province, southwestern China, 10 extreme indices were employed. Those indices were estimated based on observed daily maximum and minimum air temperature at 28 meteorological stations from 1958 to 2013. The tendency of those indices was detected by using the Mann-Kendal test method. In addition, the inverse distance weight method was used to analyze the spatial distribution of those annual and seasonal indices. Then, the changes of annual and seasonal extreme air temperature indices in the future were estimated by using the R/S method. The results showed that the frequency and duration of extreme high-temperature events were obviously higher than those of extreme low-temperature events while the increasing range of the minimum air temperature was comparatively greater than that of maximum air temperature. The annual and seasonal results of extreme air temperature presented a significantly upward trend, especially after the 1980s. Both extreme maximum and minimum air temperature in winter presented more remarkably increasing range comparing with those in other seasons; Southwestern and central region of Yunnan Province showed higher frequency and duration of extreme high temperature events than other regions. Meanwhile, the higher frequency and duration of extreme low temperature events was detected in northwestern and northeastern regions. High and low temperatures show a consistently increasing trend all over Yunnan Province in the future despite the persistence of the tendency shows diversity of spatial distribution. The persistently increasing of minimum air temperature is more obvious than maximum air temperature at annual and seasonal scales. It was noted that the most continuous increasing trend of air temperature were detected in Kunming, Jinghong, Tengchong, Shangri-La and Zhaotong cities.