According to the most stringent water resources management, provincial initial water rights allocation model was studied. Firstly, The objective functions including economic benefits of basin, optimal fairness and coordination of provinces were built. According to the constraint of the total pollutant discharge, a provincial initial pollutant discharge rights allocation model of multiple-objective is put forward. Secondly, based on the mechanism of rewarding excellence and punishing inferiority, a provincial initial water rights allocation model coupling with water quantity and water quality was built. Finally, the empirical research of Taihu Basin was adopted. The results showed that under water frequency of 75%, the amount of initial allocation water rights is 363.3 billion cubic meters and the total pollutant discharge is 54.46 billion cubic meters in the planning year 2030. The initial water rights of Jiangsu Province, Zhejiang Province and Shanghai are 135.19 hundred million cubic meters, 129.21 hundred million cubic meters and 98.89 hundred million cubic meters, respectively. The allocation model internalized externalities of over-standard or under-standard pollutant discharge to the allocation of water quantity through the function of rewarding excellence and punishing inferiority. The model integrates provincial initial water rights and initial pollutant discharge rights. Furthermore, it provides an important reference for similar research in other basins.

Rational and effective use of water resources in the Yangtze River economic belt provides an important guarantee for the sustainable development of the economy. In this paper, taking 11 provinces and cities of the Yangtze River economic belt as the research objects, we used a three-stage DEA model and the Malmquist index method to conduct static and dynamic analyses of the water resources utilization efficiency of 11 provinces in 2010-2014. The results showed that after removing the external environmental factors and random error factors, the mean pure technical efficiency and mean comprehensive technical efficiency were underestimated, the scale efficiency was overestimated, insufficient investment scale was bottleneck of our country's water resource utilization efficiency. At the same time, the differences of water resources utilization efficiency in the eastern and western provinces were significant, showing a pattern of "Eastern > middle > West". Using the Malmquist index decomposition we found that the evolution trends of total factor productivity index and technological change were basically the same, which reflected the serious dependence of the total factor productivity index on technological change. Therefore, to expand the scale of production, increasing investment in science and technology and knowledge innovation, optimizing and upgrading the industrial structure are important ways to improve water resources utilization efficiency.

To achieve the target of peaked CO₂ emission around 2030, China eventually needs to implement the policies at the regional level. Jiangsu, Zhejiang and Shanghai as the pioneer of China's economy, their energy conservation and emissions reduction policy plays a demonstration role for other provinces. Based on balanced economic growth model, in this paper we projected future energy consumption carbon emissions for Jiangsu, Zhejiang and Shanghai, simulated carbon emissions trend under different energy policy scenarios, and compared the carbon emission reduction effect from energy consumption with the baseline scenario. The results show that:(1)under the benchmark scenario, Jiangsu, Zhejiang and Shanghai's energy consumption carbon emissions peak appears in 2034, 2033 and 2032, respectively. (2)The impact of different energy policies on carbon peak is different. Under energy structure adjustment scenario and energy efficiency improvement scenarios, energy consumption carbon peak of Jiangsu, Zhejiang and Shanghai, appear before 2030, which could complete the target reaching carbon emissions peak in 2030. Comprehensive energy policy scenario simulation results show that while adjusting energy structure and improving energy efficiency, carbon emission reduction effect is more obvious.

Urban sustainable development has been the hotspot of urban geography and urban planning. In this paper we measured the compactness of urban spatial structure and urban land use efficiency and discussed on their relationship. Nanjing was chosen as the study area, and conclusions were as follows:1) the urban spatial structure of Nanjing was less compact in 2002, 2007 and 2012, the compactness of the whole city declined while that of the inner city increased. The internal filling and peri-urban expansion coexisted; 2) urban land use efficiency was on a moderate level and had a downward trend from 2002 to 2012, differences existed between different districts in Nanjing; 3) through the distance and transportation accessibility, the compactness of urban spatial structure had a significant influence on the distribution of the urban development factors, which finally influenced the urban land use efficiency. This study showed that in the process of urban development, we should optimize the inner spatial structure, especially increase investment in transportation which will help to promote the distribution and circulation of socio-economic factors, and finally improve the efficiency of the urban land use.

The research on the evolution process and characteristics of land use at different spatial scales is helpful to understand and reveal the spatiotemporal differences and internal impact mechanism of urban land use pattern. Taking the central area of Chongqing as a study case in the paper, we used multiple remote sensing images from 1978 to 2013 and landscape pattern analysis to analyze the evolution characteristic of construction land and the dynamic changes of landscape pattern in the study area from three spatial scales (the whole scale, the regional scale and the district scale). The result showed that:(1) During the period from 1978 to 2013, the trend of the construction area variation was similar to different spatial scales of the study area, and the change characteristic of comprehensive expansion degree index was shown to be a certain degree of regularity on different spatial scales. After 2001, the development of low to high speed transitional stage was displayed in the evolution process of construction land, but the construction land of district-scale was interfered by topography,economics, politics, traffic and other influencing factors; (2) By comparing the number of new patches at different spatial scales, we found that the dominant advantage had been covered three times between edge expansion type and outlying expansion type, while edge expansion type had always remained the absolute advantage in terms of the area ratio of new patches, the weak position of infilling expansion type was shown respectively in the number and the area ratio of new patches;(3) In terms of the landscape pattern indices on the whole scale, landscape fragmentation and landscape diversity had obviously increased with the change of time, the shape of patch was becoming regular and simple, and the connectivity of patch was constantly being improved. Obviously, the change of landscape pattern is consistent with the process of urbanization. However, landscape patterns were affected by the national policy environment at the regional scale and the district scale, the changes of landscape indices were relatively complex. The research conclusions have contributed to understand and excavate the urban expansion information from the spatial scale, and provide a scientific basis for the urban planning and land management.

The impact of traffic factors on urban space expansion is garnering an increasing attention from scientists. The construction of bridges and roads is important for traffic development in cities. However, the studies on the influencing mechanism of the bridge-road construction on the growth of mountain city are still limited. This study proposed three influence patterns-dotted, linear, and annular radiations-based on the impact of bridge-road construction on the location of urban developing area. We chose the northern bank of the Jialing River as the study area and investigated the influence of the construction of the Jialing River Bridge and the Huanghuayuan Bridge in Chongqing in the study area. We divided the study area into five sections, analyzed the spatial relationship between the urban area and the river bank for each section using ArcGIS, and tested the three mechanism patterns with the characteristics of the urban growth of the five sections in 1940-2009. The results showed that the urban area proportion was small and the urban expansion was slow when no bridges exited in the study area. The construction of bridges and roads accelerated the urban expansion in the study area, while the influences were different in different sections. Moreover, the bridge-road construction shifted the urban expansion center from the fifth section to the third section. The urban expansion in the third sections indicated that the influences of bridge-road construction in the form of dotted and linear radiations, and the urban expansion in the fourth section reflected the influences of bridge-road construction in the form of annular radiation. The results indicated that the proposed dotted, linear, and annular radiations provide reasonable explanations of the influence mechanisms of bridge-road construction on urban expansion in mountain cities in Southwest China.

Using several mathematial statistical methods and GIS spatial analysis technology, variation characteristics of spatial distribution pattern of five national staple crops (i.e. rice, wheat, maize, cotton and rape) were analyzed based on the area data of the crops from 1980 to 2014. The results showed that spatial differentiation of the staple crops distribution was significant. The spatial distribution of maize was relatively balanced among the different provinces, but its Area Center (AC) transferred from Shandong Province to Hebei Province since 1980. The distribution of wheat was not balanced among different provinces, but the wheat's AC always located in Henan Province and its spatial pattern did not change significantly. The spatial pattern of cotton distribution varied significantly in recent thirty years, which was characterized by its area center moving from Henan Province to Gansu Province and the migration distance of cotton's AC was much larger than the other four staple crops. The AC of rice gradually moved north since 1980 and are presently located in Hubei Province. In recent thirty years, the regions, where rice acreage increased significantly, mainly concentrated in four provinces in Northeast China (i.e. Jilin Province, Liaoning Province, Heilongjiang Province and Inner Mongolia Autonomous Region) and Yunnan Province. However, the rice acreage significantly reduced in Sichuan, Hubei, Guangxi and some provinces in Southern China. The rape's AC constantly went south from Hubei Province to Hunan Province. Moreover, there was a significant correlation between the spatial patterns of the crops with similar growth cycle in some regions. For example, when the acreage of rape increased in Sichuan and Hubei, the wheat acreage reduced simultaneously in these regions. The most obvious "growth-decline" relationship between the distribution patterns of rape and wheat arose in Qinghai, Gansu, Shanxi and Inner Mongolia, which was showed by the Pearson index smaller than -0.8. Similar "growth and decline"relationship was also found between the acreages of cotton and the maize in Shandong Province, Henan Province, Hebei Province and Shanxi Province.

Taking a land consolidation project of Yifeng County, Jiangxi Province as an example, we conducted quantitative evaluation on farmland fragmentation due to the impact of land consolidation based on the view of landscape pattern. We selected three types of landscape pattern indices, including patch-level indices, landscape-level indices, and characteristic indices of corridors. The results showed that the patch density of paddy field decreased from 8.9161 per hectare to 8.423 per hectare, the edge density of paddy field decreased from 1203.4318 to 1127.1347, and the area-weighted mean shape index of paddy field decreased from 1.2386 to 1.2163, the mean patch size increased from 0.0751 hectare to 0.0769 hectare and the largest patch index of paddy field increased from 0.17 percentage to 0.18 percentage. However, the drylands became fragmented, suggested by negative landscape pattern indices except the area-weighted mean shape index. Land consolidation led to fragmentation of the landscape pattern in the study area. The total number of patches increased from 3530 to 4175. The mean patch size increased from 0.0706 hectare to 0.0597 hectare. The area-weighted mean shape index of paddy fields decreased from 1.6723 to 1.8160. The largest patch index decreased from 2.06 percentages to 2.01 percentages. While characteristic indices of corridor improved, because of the land consolidation optimized the layout of rural roads and ditches, the construction of the corridor, such as rural roads and ditches, led to negative effects on the segmentation of landscape pitches. It is the principal cause of aggravation of fragmentation of landscape pattern. To effectively control the farmland fragmentation and improvement of the ecological benefit of land consolidation, the land consolidation planning should pay more attention on the consolidation of daylands, and the design of the layout of the corridors, such as rural roads and ditches.

We investigated the current situation of fertilization and nutrients resource input problems of households on the main crops in the Qin-Ba mountain area, which is the main rice and rape production region in Shaanxi Province. The effect of optimized fertilization, farmers' fertilizer practices and no fertilizer on the yield, economic profit, fertilizer contribution rate (FCR) and agronomy efficiency (AE) of rice and rape production under present conditions, field experiments of rice and rapeseed were conducted from 2009 to 2013 in the Qin-Ba mountain area. Compared with farmers' fertilizer practices, the yields of rice and rapeseed were improved about 703 and 341 kg·hm^-2 by optimized fertilization, the yield increase rates were 8.3% and 14.9%. The FCR to rice and rape seed by optimized fertilization were 5.2 and 7.1 percentage higher, corresponding to 0.5 and 0.6 kg·kg-1 higher of AE than farmers' fertilizer practices, respectively. The yields of rice and rapeseed could be increased by 85 and 69 thousand tons respectively through optimized fertilization, and the economic profit could be totally improved about 4.32 billion yuan in Qin-Ba mountain area. Optimized fertilization was one of the important measures to increase agricultural production, improving farmers' income and fertilizer use efficiency.

Started from October, 2002, the project of Yangshan Harbor is based on the Northern island chain by closing three main fork channels. Hydrodynamics are influenced significantly in this sea area due to this large-scale project. The observation data from several ADCP transects during October, 2002 and October, 2008 indicated that, the speed of tidal current during flood period decreased in the whole sea except near the Xiaoyangshan Island. The speed of tidal current during ebb period increased in the whole sea, but the variation range of velocity is not as significantly as that of topography changing in the eastern Yangshan Sea. To study these hydrodynamic phenomena and their variation characteristics before and after the project, five ADCP transects with seven measurements of current data in the sea were collected. In addition, a numerical model developed from FVCOM (Finite Volume Coastal Ocean Model) was applied in this sea to reproduce the situations before the project. Our results suggest that, the decrease of tidal current during flood period was mainly resulted from the decrease in flood tidal volume after the fork-closure project. However, the western flood current near the Xiaoyangshan Island was deflected to northward on the effect Coriolis force, thus the flood current near that island showed a slight increase after the project. Furthermore, the numerical experiment indicated that, the Coriolis force exerted little influence on the ebb currents, probably due to the irregular island lines on the south island chain. Since the outlet over the eastern sea dramatic converged after the project, the ebb current increased. However, the convergence of the eastern outlet also induced an occurrence of dammed water, causing a relative small increasing range of ebb velocity after the project. It should be noted that, the water level would rise up in the area near the Xiaoyangshan Island, mainly caused by the encounter of two strong flood currents. During flood period, the water level in the whole sea area after project was lower than that before project, indicating that there is no dam water occurred. Mainly caused by the tide wave reflection due to the northern straight landline, a relative longer period and larger scale of weak current field occurred after the project.

Cities are the largest carbon source and have the major contribution to atmospheric carbon dioxide under the rapid urbanization. Quantifying the urban carbon flux characteristics is very important. In this study, Eddy Covariance(EC) data and GIS tool were used to explore the footprint and carbon flux characteristics based on Eddypro and ART footprint tool in Fengxian University Town, Shanghai.The underlying surface of the study area is complex, which is composed of herbaceous, woody and other permeable layer(named as natural system) and buildings, roads and other impervious layer(named as social system). The results showed that under different wind directions, carbon flux contribution areas were expanding with the increasing atmospheric stability. When the atmosphere was under the static condition, the range of carbon flux contribution areas under non-main wind direction(the maximum range was 1100 m)was larger than that of the carbon flux contribution area under main wind direction(the maximum range was 780 m). When the atmosphere was under the unstable condition, the carbon flux contribution area under main wind direction and non-main wind direction had little difference (maximum ranges were 321 meters and 351 meters,respectively). The source and sink characteristics of different underlying surface were different. Mean annual carbon flux of the natural system with green plants as the principal component was4.1μmol/m²/s, which was a carbon sink; mean annual carbon flux of the social system was 8.6 μmol/m²/s, which was a carbon source. Carbon flux diurnal variations of natural system in different seasons were different.The variation roughly presents a "U" shape; there was no obvious seasonal difference for carbon flux diurnal of the social system.The carbon and the variable characteristics roughly presented an "M" shape. This study may be useful for establishing low-carbon city and managing urban green spaces.

In this study we investigated the effects of Spartina alterniflora invasion on soil physical and chemical properties as well as potential underlying mechanisms of these effects in the wetlands of the Yangtze River estuary. Two sampling transects in the Dongtan wetland in the Yangtze River estuary, both parallel to the dike, were set up and three sites were evenly distributed on each transect. The transect in the high tidal zone, including three sites (H-sites), was 1.5 km long, and the other transect in the low tidal zone, also including three sites (L-sites), was 0.8 km long. At each site, closely adjacent S. alterniflora-Phragmites australis (H-sites) and S. alterniflora-Scirpus mariqueter (L-sites) stands were selected. In each of the adjacent stands, three plots were randomly selected for plant and soil sampling. This experimental design was used to minimize the potential effects of heterogeneous environmental conditions, such as tidal inundation in the wetland. In S. alterniflora stands, soil temperature was not significantly different from that in the native plant stands. Soil moisture was significantly higher in S. alterniflora stands than that in the native stands in both H-sites and L-sites. Soil pH was not affected by plant invasion or tide zones. At H-sites, soil salinity and sulfate content in S. alterniflora stands were significantly lower than those in P. australis stands, while there was no difference in soil salinity and sulfate content between S. alterniflora and S. mariqueter stands at L-sites. At H-sites, the soil Fe(III)/Fe(II) ratios in S. alterniflora stands were significantly lower than in P. australis stands, but were significantly higher than in the S. mariqueter stands in L-sites. In both H- and L-sites, plant biomass were significantly higher in S. alterniflora stands than those in the native plant stands. S. alterniflora stands experienced significantly higher SOC and SMBC than the native plant stands in both H-sites and L-sites. There were no significant difference in soil inorganic carbon (SIC) between plant species or tide zones. Estimated SIC in the Dongtan wetland accounted for more than 60% of total carbon in soil. The lack of difference in SIC between S. alterniflora and the native plant stands suggested that total carbon in coastal wetland soils cannot appropriately reflect the effects of S. alterniflora invasion. These results indicate that S. alterniflora invasion has significantly impacted soil physical and chemical properties of wetlands in the Yangtze River estuary and these effects differed greatly between tidal zones. These findings suggest that S. alterniflora invasion may profoundly impact decomposition of soil organic matter, biogeochemical processes as well ecosystem structure and functions through altering soil properties.

Under the background of global warming, the interaction of temperature and rainfall makes the agricultural meteorological disasters occur frequently, causing destructive risk to agricultural production. In this paper, we collected daily data of rainfall and temperature observed at 24 meteorological stations in Anhui Province in the period of 1980-2014 and collected the monthly average rainfall data of each station. We calculated the moment average rainfall of each station by subtracting average monthly rainfall data from the monthly raw rainfall data divided by the average. Finally, we used the average of moment average rainfall of 24 stations as rainfall data of Anhui Province. According to the rainfall frequency histogram, the distribution of rainfall data was asymmetric, showing some level of right-skewness. According to the temperature frequency histogram, the distribution of temperature data was basically symmetric while presenting "peak thick tail" features. Therefore, we determined the marginal distributions of temperature and rainfall data through non parametric kernel estimation method. The frequency histograms of rainfall and temperature showed that there was a negative correlation between them, suggesting that the diagram presented the symmetric upper and lower tails of rainfall and temperature. Based on this symmetry, we selected three types of Copula functions, i.e., normal Copula, t-Copula and frank-Copula. Finally, based on the principle of minimum squared Euclidean distance, bivariate t-copula function is chosen to draw the probability density function of rainfall and temperature. The results showed that from the perspective of joint probability distribution of temperature and precipitation in Anhui Province, when the rainfall was rising, the temperature dropped; or when the temperature was rising, the rainfall decreased. There was a medium negative correlation (-0.280) between rainfall and temperature. From the perspective of probability density function diagram of t-copula and upper and lower tail correlation coefficient, the temperature and rainfall in Anhui Province had a relatively obvious dependence relation in extreme, which means, when the temperature and rainfall were beyond normal range, their dependence changed from negative correlations to positive correlations. This phenomenon would occur more in extreme weather conditions, such as extreme high temperature or rainstorm.

Due to the effect of monsoon climate and river-lake interactions, a seasonal water-level fluctuation pattern, i.e. rising seasons, flooding seasons, retreating seasons and dry seasons appearing consecutively, has been formed in the two river-connected lakes, the Dongting Lake and the Poyang Lake. In the recent three decades, dramatic changes occurred in these two lakes due to climate variation and built dams on the main stream of the Yangtze River. The Dongting Lake and the Poyang Lake are both located in the south of Yangtze River with similar climates, and probably with rather similar drainage structures. While, the Dongting Lake and the Poyang Lake are also linked by the upstream and downstream relations. Hence, the climate variations and river-lake interactions affect water regimes of those two lakes both similarly and differently. Contrasting of water regime variation of those two lakes is conducive not only to understanding river-lake interaction in middle reaches of the Yangtze River, but also to improving lake governance. In this research, taking the year 2003 as the breakpoint (There are two periods:1980-2002 and 2003-2014), comparative analyses were performed about the hydrological data of both two lakes and the multi-site in a single lake. How river-lake interactions affect the water regime variation in those two lakes was also discussed. The results showed that (1) compared to the former period, in both dry and rising seasons, the water level declined in the upstream region of each lake during the later period, while the lake water level fell even more in the middle region of each lake. Eventually, the lake water level rebounded decreases in the downstream region of each lake. 2) In both the flood and the retreating season, magnitudes of water level fluctuations in both lakes have changed considerably since 2003. For the Dongting Lake, the biggest water level decline in flooding season occurred at the upstream region and the middle region of the lake, while the biggest decline in the retreating season occurred at the middle region and the downstream region of the lake. Unlike the Dongting Lake, the declining amplitude of water level in the Poyang Lake expanded from the upstream region to the downstream region in both the flood season and the retreating season. (3) The water level drops in the Dongting Lake were significantly less than that in the Poyang Lake. Different mechanisms and intensity of river-lake interactions are mainly responsible for these disparity in variations magnitude of those two river-connected lakes in the middle reaches of the Yangtze River.

The natural hydrological rhythm has been altered under the combined effect of climate change and intensifying anthropocentric activities during the past decades at Poyang Lake, the largest freshwater lake in China. The main objective of this paper is to analyze the change process of water-levers at different time scales. In this research, the fluctuation characteristics of water-lever, such as monthly changing feature, annual variance tendency, extreme values, saltation feature and periodicity, were evaluated by using statistical analysis, trend analysis, Mann-Kendall non-parameters test and wavelet analysis methods based on the observed daily water-level time series from Hukou Station, Xingzi Station, Duchang Station, Wucheng Station, Tangyin Station and Kangshan Station at Poyang Lake. The main findings are shown as follows:the water-level drastically fluctuated during months and the highest water level (17.75m) and lowest water level (10.8 m) generally appeared in July and January, respectively, with an amplitude of 6.95 m; although the water-level presented a feeble downward trend during the past decades, a rapidly descending amplitude occurred after 2003, accompanying extremely low water level situation; there are three obvious saltation points at 1955, 1965 and 2006, and the maximum water-level variation is close to 2 m; periodicity, effected by many factors, is inconspicuous only with a weak periodic in 28 time scale. Results of this study demonstrate the change situations of water-level at Poyang Lake in annual and inter-annual, which will provide instruction for water security associated with flood control, drinking water usage and water ecology in the lake basin. Furthermore, the results can be applied as a foundation for drawing scheduling rules of reservoirs.

In this work we combined in-situ test and laboratory experiment methods, and selected COD_Mn, TN, TP and ammonia nitrogen as the pollutant indicators, to calculate the degradation coefficient of pollutants and analyzing the regularity of the degradation. The results showed that:(1) In the in-situ test, the pollutants degradation coefficients for the riparian monitoring section was significantly smaller than those for the river center monitoring section, but they had the same degradation trends. Compared with the various factors between the shore and river center, except for the velocity of shore and river center, the temperature, DO and pH had no significant difference, suggesting the velocity was the influencing factor of the pollutants degradation coefficient, and the greater of the velocity, the greater of the degradation coefficient;(2) In the laboratory experiment, the pollutant degradation coefficients gradually increased along with the increase of flow velocity(0.4~2.0 m/s), which was the same as in the field in-situ test, suggesting the velocity was the influencing factor of the pollutant degradation coefficient. Based on the results of both field in-situ test and laboratory experiment, we used structural equation modelling to quantitatively analyze the relationships between pollutant degradation coefficient and the impact factors. The results showed that the flow velocity was an important factor for the degradation coefficient. Finally, based on the quantitative results of the structural equation model, we regarded the pollutants degradation coefficient as a function of velocity, and the empirical formula was fitted by the wild field measurement data. In our study condition range, the empirical formula can be applied to quickly calculate the coefficient of pollutants degradation.

As one of the most serious meteorological disaster, droughts affect the society, economy and the people's livelihood severely. Since the coming of twenty-first century, there are more frequent droughts in the Southwestern region of China. The serious phenomenon is spreading from Northern China to Southwest China. In order to better understand and comprehend the evolution characteristics of droughts in the Southwestern region of China, the changes of droughts in the different time periods (1961-2013) in the Southwest Yunnan area were systematically analyzed according to the evaluation criteria of Standardized Precipitation Evapotranspiration Index (SPEI) and Standardized Precipitation Index (SPI) as well as the Mann-Kendall (MK) test method and Morlet wavelet analysis. The experimental results indicated that the weather status based on SPI index tended to become remarkably drier than that based on SPEI index in the former 33a in the Southwest Yunnan area. In the following 20a, the contrary is the case. On account of the same evaluation index, the frequency and occurrence time of droughts at the same time period was fundamentally consistent. In terms of the two indices, there were about 3a of periodic changes at four time periods. In the 53a, it tended to become dry based on the evaluation of two indexes in from December to June in the next year and from November to June in the next year. It tends to become slightly dry based on the SPEI index from December to May in the next year and from November to May in the next year while it tended to become slightly wet based on the SPI index. According to the spatiotemporal distribution of dry and wet weather, there were great differences in the spatial distribution of change patterns and change scope in the four time periods that were easy to have droughts based on the evaluation of the two indices, The main reason is that the water balance (precipitation minus evapotranspiration) was increased with the notable increase of the temperature in the researched area. Compared with SPI, SPEI has covered the impact of thermal factors in the potential evapotranspiration, therefore it is more effective to investigate the evolutions of the regional droughts under the background of climate warming.

The processes of soil erosion may be determined by two aspects:the erosive agents and resistance to erosion, and it is necessary to study flow hydraulics to understand mechanisms of water erosion and to predict soil loss. A series of experiments were conducted to assess the difference of flow hydraulics under the coexisting conditions of rainfall and inflow and to understand the relationship between flow hydraulics and soil erosion amount. A soil pan (3.0 m long, 0.5 m wide and 0.35 m depth and with an adjustable slope gradient of 0°-30°) was subjected to designed rainfall intensity (60 mm·h^-1, 90 mm·h^-1 and 120 mm·h^-1) and inflow rates (10 L·min^-1, 15 L·min^-1 and 20 L·min^-1). Our results suggested that both rainfall intensity and inflow rate played important roles in runoff formation, soil erosion and hydraulic characteristics. The average flow velocity (V), the mean flow depth (h) and Reynolds number (Re) and the stream power (w) increased with rainfall intensity and inflow rate, and the rate of Manning roughness coefficient to mean flow depth (n/h) showed opposite trends. There were no obvious trend for the other flow hydraulics. The average flow velocity ranged from 0.21 m·s^-1 to 0.45 m·s^-1 and the mean flow depth from 5.6 mm to 9.4 mm. Overland flow regimes existing in the slope were almost considered as turbulent and supercritical. The results indicated that the parameter of Manning roughness coefficient to mean flow depth was probably a better hydraulic parameter to predict sediment load and runoff rate in hillslope erosion processes of red soil under the coexisting conditions of rainfall and runoff.