Abstract:he study analyzed the effect of different vegetation on soil physicochemical properties and anti-erodibilty using the fractal theory． The results show that the soil under Hedysarum monglicum had a higher content of 1 ～0． 25mm soil microaggregates and particles than those under the other vegetations． Microaggregate factal dimensions of the soils under Caragana korshinkii and Hedysarum monglicum were lower than those under the other vegeataions，even significantly lower than that of bare sand． The highest particle dimensions were found in the soils under Artemisia desertorum and Hedysarum monglicum，and the lowest was in the soil under Caragana korshinki． Bare sand presented the highest erodibility value (K) while the soils under Hedysarum monglicum and Hedysarum scoparium had the lower ones． It can be concluded that the vegetation on bare sand could improve the soil quality and anti-erodibility，and Hedysarum monglicum could be the best choice as plant for improving soil quality according to the findings of this study．

Abstract:Monthly meteorological data were obtained from typical weather stations located in the upper Heihe River．The influences of climatic factors on the runoff of the river from the mountain areas in the last 50 years were investigated using correlation，multivariate regression，analysis of variance，and trend analysis． The results of correlation show that winter and summer precipitation，summer and autumn mean lowest air temperature had close correlation with the runoff volume． Based on the close relationship，multivariate regression models were then developed to simulate the temporal variations of the runoff from the mountain areas． However，summer mean lowest air temperature showed little contribution to the runoff based on the regression analysis． The annual variations of the runoff were controlled by the precipitation amount in summer． Trend analysis results further confirmed that the runoff varied consistently corresponding to the summer precipitation over time scales of decades．

Abstract:The relationship between soil fractal dimension and soil properties under five vegetation types (Quercus aquifolioides，Abies taxoniana，Sinarundinaria fangiana，board leaved forest and subalpine meadow) in upper reaches of Minjiang River was studied based on data of the soil particle composition and fractal theory． The fractal dimension of surface soil particle size distributions of the fifteen plots ranged from 1． 117 to 1． 315． This fractal dimension only had a significant correlation with the content of ＜ 0． 002 mm soil particles by stepwise multivariate regression． The infiltration process was divided into three phases according to the soil infiltration process curve: (1) the initial phase(0 ～8 min); (2) the transition phase(8 ～ 30 min); (3) the stable phase(30 ～ 120 min)． Soil infiltration process was influenced comprehensively by soil partical size distribution(PSD)，aggregate size distribution(ASD) and soil pore size distribution(SPD)． During the process of soil water infiltration，the infiltration rate of Quercus aquifolioides，Sinarundinaria fangiana and board leaved forest was faster than that of Abies taxoniana and subalpine meadow．

Abstract:Spatial distribution of total nitrogen(TN) and total phosphorus(TP) in soils under three riparian forests were studied with a dense equidistance sampling scheme．The results of correlation and principal component analysis showed that the contents of TN in surface soil were significantly higher than those in subsoil，while the contents of TP in surface were that almost same level with those in subsoil． The contents of TN and TP of the spruce forest soil were the highest，followed by the mixed forest of Populus and oak，and the soil under the mixed forest of larch and oak had lowest levels． The main factors affecting TN distribution were organic carbon and vegetation coverage，and soil depth and bulk density controlled the distribution of TP．

Abstract:Through the field survey and laboratory analysis，soil profiles with various land uses were characterized regarding soil organic carbon variations and storages in the Zhifanggou watershed in the loess hilly region． The results show that the soil organic carbon contents in different soil layers varied moderately，increasing with soil depth，in the study area． Approximately 4．73 ×10⁴t soil organic carbon was stored in 0-60 cm soils in the watershed，which was mainly distributed in natural grassland and forest，accounting for 80% of the total amount． Under different types of land use，the soil organic carbon content in the Zhifanggou watershed differed significantly，in a descending order as:natural grassland ＞ shrub ＞ forest ＞ dammed valley ＞ terrace farmland ＞ slope land ＞ abandoned land ＞ orchard．

Abstract:A number of experiments with artificially simulated rainfalls were conducted to study the effects of straw mulch and stubble on soil and water conservation． The results show that both straw mulch and stubble delayed the runoff initiating time，by 427% and 19% for the treatments with straw mulch applications of 5 000 and 3 000 kg/hm²，and by 107% and 76% for the treatments with 30 cm high stubble and the combination of 15 cm low stubble and straw mulch，respectively． Compared with the control，the cumulative amount of runoff and sediment was reducedby 61． 72% and 86． 7% in the treatment with straw mulch application of 5 000 kg/hm²，and by 6． 26% and 60． 1%with straw mulch application of 3 000 kg/hm²，respectively． Straw mulch，especially with high application rates，could effectively control soil water erosion． In contrast，30 cm high stubble reduced soil erosion by 62． 9% and 15 cm low stubble by 25． 6%． Both of the stubble treatment could effectively reduce the soil erosion，but showed no significant effect on surface runoff．

Abstract:On the soil profiles under typical planted and natural secondary forests in Simian Mountains of Chongqing City，soil saturated hydraulic conductivity(K_s) was measured by the constant-hydraulic head method，and the correlations between K_s and soil physical features and organic matter contents were established using multivariate regression and path analysis． The results show that，the values of K_s decreased negatively exponentially with increasing soil depths． Comparing to the control，K_s was significantly improved in all the forests，with effects in a descending order as: natural secondary Conifer × Broadleaf forest land ＞ natural secondary Broadleaf forest，Phyllostachys pubescens forest，Conifer forest land ＞ Broadleaf plantation，Conifer × Broadleaf plantation，Conifer plantation land ＞ wasteland． Soil clay content，bulk density，non-capillary porosity and ＞0． 25 mm aggregate content were the key factors affecting K_s． The Forests encouraged effectively the accumulation of organic matters in the soils． The relationship between K_s and organic matter was well described with quadratic equations． Mixed mode of Conifer × Broadleaf with multiple layers is recommended in forest plantation and management．

Abstract:To evaluate the impacts of different revegetation methods on soil nutrients，this study combined laboratory analyses with field surveys in two watersheds: one subjected to artificial restoration (AR) and the other to natural recovery (NR)． The results show that，after 11 years of restoration，the soils in the AR watershed were more acidified than those in the NR watershed． In the soil of 0-60 cm，total N，total P，and total K contents in the AR watershed soils were higher than those in NR watershed soils，with greater coefficients of variation． In contrast，the NR watershed accumulated more soil organic carbon of both heavy and light fractions，in the same soil layers． The contents of light fraction soil organic carbon differed most between the surface soils of the two recovery methods，while much less in the lower soil layers． The coefficients of variation of the organic carbons fraction in the soils of the AR watershed were higher than those of the NR watershed soils． The results indicate that the processes of artificial restoration and natural recovery accumulate soil N，P，K and organic carbon in different ways．

Abstract:With Kenjiandao 5 and Kendao 12 as experiment materials，the effects of before-heading water supply on the quality of rice in cold region were studied through pot planting in a rainproof chamber． The soil water potential (SWP) was monitored with negative pressure soil moisture tensiometers． The results show that with intermittent water control at SWP ranged from －10 to －8 kPa during the before heading stage，the whole rice rate was significantly improved for Kenjiandao 5 rather than Kendao 12，and the ratios of length to width decreased for the grains of both varieties． With the before-heading water control，the chalkiness rate and chalkiness degree were improved for the dominant grains and were reduced for the middle grains，implying possible reductions of amylose content for both varieties． Protein contents of all the grains of both varieties were enhanced，while the dominant grains received higher grades in regard to the taste and the middle grains had lower grades． With water controls at SWP of －18 ～ －20 kPa and －28 ～－30 kPa before heading，the plants of the two varieties performed similar to those with the first treatment，except the chalkiness rate，chalkiness degree and taste grades were reduced for all the grains of both varieties．

Abstract:Based on field test，the effects of mutifunctional soil amendments on soil physiochemical properties and economic benefits of corn were studied in a sandy soil in Hexi area． The results show that the effects of the amendments followed a descending order as: cow dung ＞ furfural residue and SAR ＞ fertilizer ＞ poly-vinyl alcohol． The combination of A₁B₁C₂D₃E₃(cow dung 7． 82 t，furfural residue 6． 00 t，special fertilizer 1． 04 t，polyvinyl alcohol 0． 09 t，insurance agent 0． 05 t) displayed the best amending effects． The application amounts of the muti-functional soil amendments were found correlated positively with the values of soil porosity，aggregate structure，volume of water，organic matter，available phosphorus，available potassium，and EC，and negatively with the values of bulk density and pH value． Marginal yields and profits decreased with increasing application amount of the multi-functional soil amendments． The pure interest rate decreased as an extra amount of 3． 75 t/hm² was applied over the base amount of 15． 00 t/hm²． Based on statistical regression，the optimal application would be 15． 00 t/hm² with a theroetical corn yield of 7． 03 t/hm²，which agreed well with the field tests．

Abstract:Four rare shrubs found in west Ordos，including Ammopitanthus mongolicus，Tetraena mongolica，Helianthemum songoricum，and Reaumuria trigyna，were selected to study the variations of organic matter content，total N，total P and soil pH in soils of the rhizosphere and surrounding matrices． The results show that the contents of organic matter，total N，and total P of the soils in the rhizosphere were 26． 8%，19． 2%，and 13． 9%，respectively，higher than those in the surrounding matrices，while the soil pH value was 0． 23 unit lower than the average． Except for H．songoricum，soil nutrition in the rhizosphere differed significantly from that in the surrounding matrices，showing that the three shrubs have positive rhizosphere effects on soil nutrients． The rhizosphere of the four shrubs showed positive effects on nutrient enrichment，providing potential benefits to improve and restore the desert soil environment．

Abstract:This paper studied vegetation cover variations and the response of vegetation changes to climate change in Daba Mountains from 1998 to 2009 based on SPOT-NDVI data． The result as follow: (1) The vege-tation cover has a significant increasable trends as a whole in Daba Mountains during 1998 to 2009，the value of annual NDVI is between 0． 54 and 0． 65，the NDVI value is higher in mountains，and lower near the river in space; The major area of vegetation cover had undergone changed in last decade，and the result has through the significant test ． The sign of vegetation degradation distributed near the city，for the total area of 0． 24%． (2) During the past 12 years，six types of vegetation cover tended to growth in significantly in seasons，especially in the spring． Beginning with the largest，the NDVI values of different vegetation types is broad-leaved forest，coniferous forest (the values is coniferous forest ＞broad-leaved forest in winter)，shrub，meadow，grass and planting vegetation，which meadow of the amplitude maximum． (3) In the scale of time，the NDVI value showed significant correlation with temperature of current month，the previous month and two months before the current month． The pixels of average NDVI value in June which are negatively correlated with the temperature account for 67% of the total，which showed that the rise of temperature could lead to the increase of evaporation，thus restrain the growth of plants．

Abstract:Five land-use types were chosen to study soil anti-scourability characteristic in a small watershed called Lüergou watershed in Loess Plateau using flume method with undisturbed soil． The results showed that: (1) The order of soil anti-scourability under different land-use types was: locustland ＞ grass land ＞ terrace land ＞ orchard land ＞slope farmland． (2) Plant roots exerted significant influence on soil anti-scourability，and compared with soil without root，the anti-scourability of soil with root was obviously improved by 44． 02% as an average． (3) The soil anti-scourability decreased with the increase of gradient，especially for the range of 22° ～ 25°． (4) According to the spatial simulation of soil anti-scourability on the scale of watershed，it is greater as getting closer to the upstream of watershed and upper slope position of erosion gully，which is more obvious under locust land and grassland．

Abstract:Freezing and thawing cycles occur very often in the Qinghai-Tibet Plateau due to its unique environment with high elevation and cold temperature． The frequent freezing and thawing cycles lead readily to wind erosion during the dry windy conditions，resulting in the emergence of desertification． Freezing-thawing induced wind erosion prevails as a major form of erosion on the Qinghai-Tibet Plateau． Based on simulated experiments using soil samples on the surface of the Plateau，we found that the wind erosion intensity increased with the frequency of the freezing-thawing cycles，the water content of the soil，and the temperature difference in the freezing-thawing process． It is concluded that，the damage of soil structure caused by the repeated，fierce freezing-thawing behaviors was the main reason for wind erosion in the plateau，and the sand-suspended wind was the main driving force．

Abstract:Effect of nitrogen of different forms on Sorghum sudanense root morphology and lead(Pb) absorption and accumulation under Pb stress were studied using hydroponics experiment，addressing the interaction between the plant and different nitrogen forms and heavy metals for phytoremediation application． The results indicate that the different N forms had some insignificant effects on the root morphology of S． sudanense with Pb pollution level of 0． 5 mmol/L． However，the MDA(Malon dialde hyde)contents of the roots and the biomass of each organ of S． sudanense were significantly(p ＜0． 05) influenced: the MDA content of S． sudanense root in the NH⁴-N culture solution was 4． 6 and 1． 6 times higher than those in NO³-N and NO²-N culture solutions，and the root，stem and leave biomasses in the NO³-N culture solution were higher than those in NH⁴-N culture solution by 28． 7%，19． 6% and 23． 9%，and higher than those in NO²-N culture solution by 37． 6%，30． 9% and 36． 7%，respectively． With Pb pollution level of 0． 5 mmol/L，the root in NO³-N treatment had the largest enrichment coefficients and Pb concentration that was over 2 times higher than that in NH⁴-N culture solution，and Pb concentration of the stem in the NO²-N treatment was over 8 times higher than that of NH⁴-N treatment，indicating a high transport capability of Pb． This suggests that if the existence of different forms of nitrogen in the eutrophication water with heavy metal pollution may to some extent weaken the toxic effect of the heavy metal on the remediating plant，and increase the environment capacity of the water．

Abstract:Both the morphology and architecture of fine roots vary according to the stage of development，which directly influences their ability to absorb water and nutrients from the soil，and consequently，influences plant growth． To understand the effect of N fertilization on the fine root architecture and growth dynamics of Bothriochloa ischaemun，six N treatments (0，0． 02，0． 04，0． 08，0． 16，0． 32 g/kg) were carried out under greenhouse conditions． Using a scanning method we monitored root extension and radial growth dynamics． The scanned pictures were analyzed to obtain root length，diameter，and surface area． Dynamic cluster analysis was then used to sort the root orders according to the morphological factors． After scanning，we flushed the roots，and then dissected the individual roots according to the branching orders． The fine root samples were scanned to determine root length and diameter，and specific root length． The root was oven-dried at 65 ℃ for 48 h before being weighed． The results showed: (1) the mean fine root diameter and mean root length tended to increase (p ＜ 0． 05) with ascending root order，while both specific root length (SRL) and total root length decreased (P ＜ 0． 05); (2) the mean root diameter and mean root length increased with increasing N fertilization，however，the SRL，total root length and root biomass decreased with increasing N，except the diameter of the 1st order root; (3) N fertilization increased the root extension rate (RER) and increased radial growth rate (RGR)． The RER and RGR for all four root orders first increased to peak levels，which then decreased，and finally held constant．

Abstract:Numerous debris flows were triggered by the Wenchuan earthquake，bringing a large number of casualties and property loss to the mountain area． For better understanding and prediction of debris flow，particle size analyses were carried out on field samples of debris flow deposits． Fractal structures of debris flow deposits were also analyzed based on fractal theory in the area． The fractal dimension ranged from 2 to 3，with an average of 2．49 and standard deviation of 0． 19，showing a low dispersion degree of fractal dimension． The influences of lithology，total volume of loose materials，and slopes on the particle composition of debris flow deposits were studied． The results show that the deposits of siltstone have the minimum fractal dimension value，followed by those of sandstone and marl． In contrast，the deposits of quartz diorite and limestone have the highest and the second highest fractal dimension value． The fractal dimension values of the deposits increases with the total volume of loose materials，as well as the gully slope． The fractal characteristics of the deposit indicate the risk of debris flow，providing evidences for characterization and prediction of debris flow activities．

Abstract:The effects of groundwater depth and mineralization on the photosynthetic characteristics and growth of T． ramosissima were studied in the treatments with factors of mineralization ( ＜1． 00，1． 0 ～3． 0，and 3． 0 ～10． 0 g/L) and groundwater depth (20，60，and 100 cm) for a duration of 60 days in the national research station of Akesu oasis farmland ecosystem． The results indicate that the combination of groundwater depth and mineralization showed signifi- cant effects on the photosynthetic characteristics and growth of T． ramosissima seedlings． According to the results ob- tained from the experiment，it was found that with groundwater at 20 cm depth and saline condition，the plant showed the highest maximum photosynthetic rate〔66． 93 μmol/(m2·s)〕，stomatal conductance，water use efficiency and carboxylation efficiency． The values of maximum net photosynthetic rate，apparent quantum yields，light saturation point and dark respiration rate were affected by the variations of groundwater depth and mineralization． These results revealed that with 20 cm watertable and saline condition，the seedlings of T． ramosissima show stronger competency and have higher capacity to accommodate the variations of the environment．

Abstract:Based on telemetering pluviograph data at the intervals of 15 minutes，the precipitation events were extracted according to minimum inter-event time，and the complex orographic effects on precipitation characteristics were analyzed in spatial and temporal scales in Yinzhou District，located in Ningbo City，Eastern Zhejiang Province． As confirmed by the results，the amounts and frequency of precipitation demonstrated a significantly close correlation with the elevations in various years，and the relative larger total rainfall amounts in the mountainous areas were partly attributed to the increments of precipitation frequencies． On the other hand，the relationships between rainfall intensity，duration and elevation were found more complex，and the orographic effects were not consistent on different types of precipitation controlled by various weather conditions． The number of rainfall events that had intensities less than 2mm/h or durations of 2 to 5 hours increased significantly as the elevation rose，and this trend had been observed consistently in different years． The relationship between elevations and the frequencies of the rainfalls with high-intensity，or shorter and longer duration was more complicated，showing more random effects．

Abstract:A tailings pond in Guangxi Province was chosen as the study area． Groundwater tracer test was carried out to obtain the time-concentration curves． The velocity of groundwater flow，coefficient of dispersion，and dispersity were obtained by means of the groundwater dispersion model developed using the data from the test． The mechanism of multimodal and double-humped curves was also analyzed． The experimental results show that the calculated flow velocity was in general close to the apparent velocity． The leakage path with the giving and receiving locations of the tracer，the direction of groundwater flow，and hydraulic connection matched well with the observations． The method can provide technical references for future water pollution evaluation and construction of trailings ponds．

Abstract:The edge effects of plant communities were investigated in a wetland-dry grassland ecosystem of Siertan wetland in Yanchi County，Ningxia Hui Autonomous Region． Based on the importance values，the indices of abundance，diversity and ecological dominance were calculated to analyze the changes and the major environmental factors of plant community structure among three strips and three lines in the ecosystem． The calculated indices show that the vegetations of the investigated area were growing well during the years from 2005 to 2007． However，the exuberant growth had been retarded from 2008 to 2010． Among these five years，the vegetation in 2007 exhibited the best growing condition，while that in 2010 showed the worst． The edge effect was amplified apparently in the community ecotone of wetland and arid grassland，where had the highest ecological dominance (SP)，richness indices (R) and diversity (SW) indices． The dry zone was the most disturbed area by the railway construction． Observations indicated that the changes of vegetation growth in the ecotone were highly related to the amount and frequency of the precipitation．

Abstract:In order to evaluate the hydrological functions of dwarf bamboos，the water holding capacity and the rainfall interception rates of four dwarf bamboos，such as Arundinaria argenteostriata，Arundinaria fortunei，Shibataea chinensis and Sasaella masamuneana were investigated． The results show that the litter volumes of Arundinaria argenteostriata，Arundinaria fortunei，Shibataea chinensis and Sasaella masamuneana were 4． 51，4． 33，6． 32，and 6． 67 t/hm²，respectively． The maximum water-holding volumes of these four dwarf bamboo litters ranged from 12． 77 to 16． 66 t/hm²． The rainfall interception rates of the litters were closely related to the thickness and their water contents，and the interception rate of the litter with 1 cm thickness was significantly different from that of the litter with 3 cm thickness．With the increment of litter thickness，the interception rates increased when the litter water contents were 50． 81% ～66． 27%． The 3 cm litter intercepted more rainfall than the 1 cm litter，by 126%，51． 4%，114． 3%，and 56% more for Arundinaria argenteostriata，Shibataea chinensis，Arundinaria fortunei and Sasaella masamuneana，respectively．

Abstract:The effects of drought stress，simulated using polyethylene glycol(PEG-6000)( －0． 03，－0． 10，－0． 24，－0． 42，－0． 65，－0． 94 MPa)，were investigated on the germination of the seeds and the growth the seedlings of two plant species，Sophora alopecuroides L and Swainsonia salsula (Pall． ) DC． which are dominant local species on the desert edge in the middle of Hexi Corridor． The results show that with increasing stress from PEG，water absorbing rate，germination percentage，germination index，vigorousness，seedling height，root length，and saturated water content of both species decreased，whereas dry weights of seedling and root，and crown-root ratio increased and then decreased． This indicates that appropriate drought stress might improve the drought resistance and then the quality of the seedlings． Possible causes for this adaptation to drought stress by the two species were explained and discussed．

Abstract:Employing the annual mean precipitation and temperature data from 96 meteorological stations in Shaanxi Province during the period from 1961 to 2009，and the water resource data published by Chinese Ministry of Water Resources from 1997 to 2006，the impacts of climate change on water resources of Shaanxi Province were analyzed by linear regression，water resource evaluation index，variation coefficient，and water mode． The results show that，the water resource assessment model based on both precipitation and temperature data was more reasonable in evaluation than the one merely based on precipitation data． The climate had become warmer and drier in the past fifty years，the annual mean temperature increases substantially around 1996 and the annual precipitation decreases sharply around 1988． With the declining precipitation and increasing temperature，the water resources had gradually reduced in the past 50 years，and worsened around 1991． The water resources were more than enough before 1990． Since then，the water resources were less than enough with more significant interannual variations． The water resources are limited in drier years． The reduction in natural water supply enhanced the water use efficiency in the living，industrial and agricultural activities and increased the pressure from water supply and demand．

Abstract:In this study，we selected 107 landslides in the earthquake-stricken area for investigation． The geometric features of the landslides were extracted based on remote sensing，DEM(digital elevation model) data and field survey．The area of the landslides was obtained by interpreting individual landslides from remote sensing images． The apparent friction angles，travel distances，and the heights of the landslide bodies were extracted from remote sensing images combined with DEM． The total volumes of the landslides were gained by field survey． Furthermore，we linked the total volumes and travel distance of the landslides with the other geometric features factors，such as the areas，apparent friction angles and heights． The results indicate that the total volumes had significant relationship with landslide areas and landslide heights，which could be described well by a power equation and a quadric polynomial equation，respectively，while the travel distances correlated significantly linearly with the landslide heights． However，the other relationship was not statistically significant．

Abstract:Chosen Hanyin County of Shaanxi Province as the study area，this research intended to assess the quantitative methods of farmland productivity evaluation． On the basis of field investigations，sampling and chemical analysis，the automatic and quantitative evaluation procedure was realized by adopting the modified grey relation model，which was improved with incorporation of analytics hierarchy process and fuzzy math． The proposed evaluation method is of positive significance in scientifically managing and utilizing the cultivated land resources in China． The results show that farmland productivity in the study area could be classified into five grades，with grade Ⅰ accounting for 7． 32% of the total area，grade Ⅱ for 15． 41%，grade Ⅲ for 21． 61%，grade Ⅳ for 32． 47%，and grade Ⅴ for 32． 47%，respectively． The results also indicate that the farmland productivity in the study area ranged from inferior to intermediate; the farmlands of the river valleys have relatively high productivity，the farmlands of the rolling-hill areas have low productivity，and the farmlands of mountainous areas have the lowest．

Abstract:The application of the artificial network drainage system in the techniques of dam construction using slurry pumps provides practical examples and theoretical guidance for building mud dams in the heavy silt loam region，as well as scientific basis for promoting and populating this technology in the similar areas． The loess soils from Dagou basin near Xiwu village of Baishui County in Shaanxi Province were collected as study materials． The layout of drainage system，construction methods and drainage effects were investigated and compared in this study． The designs and the layout of the drainage pipeline influenced decisively the effectiveness of the drainage． The drainage system using polyethylene corrugated pipes with micro-apertures could speed up the dehydration and consolidation of the dam to some extent，but the effect was not highly significant． The heavy silt loam had a high content of clay，which lead to the difficulty in drainage． The utilization of artificial network drainage technology in building dams with mud pumps in deed accelerated the dehydration and consolidation of the dams，although the effects were not highly significant． More investigations are required in selecting optimal pipes as filtering materials，designing drainage pipes reasonably and improving the layout plans．

Abstract:Based on measured water contents and spectral reflectance of the bacterial spots on tomato leaves，we attempted to estimate the water contents of diseased leaves using the Gram-Schmidt transformation algorithm． The results show R₆₉₄ in visible and R₇₆₁，R₁₄₄₆，R₁₉₄₀，and R₂₄₉₀in near-infrared wavelengths were the spectra sensitive to the variations of water contents． Non-linear regression models were then developed to predict water contents using reflectance at R₁₉₄₀ and R₂₄₉₀ using Gram-Schmidt orthogonal transformation algorithm，with high R²(0． 724)，low relative error (0． 52%) and RMSE (0． 13)． This model was proved superior to the traditional linear model． The findings of this research can provide technical supports for diseases diagnosis of tomato plants under stress．

Abstract:On the basis of spatial Kriging interpolation，grid calculation，and regional statistics of ArcGIS，the spatial patterns of natural suitability of human settlements in the Guanzhong Region have been evaluated using annual average temperature，monthly relative humidity，and average precipitation from 68 meteorological stations in the region during the period of 1971-2000． Spatial data was also collected from maps of water bodies and population，a 1∶ 250 000 DEM，and a remote sensing image(TM) of 2005． Furthermore，the suitability and limiting factors in each region were analyzed through Hopfield neural network clustering． The analysis results indicate that: (1) the natural suitability of human settlements in the region has a layered distribution pattern． The human settlement index of an area increases with distances to the densely populated center． The suitable area is most widely distributed，accounting for 42． 46% of the total area of the region; the moderately suitable area is the second，accounting for 29． 77%; the unsuitable area accounts for 15． 13%; the highly suitable area distributed sparsely，accounting for 12． 64%． The total population of 22． 27% in the region is distributed in the unsuitable area; the total population of 61． 95% is distributed in the moderately suitable and suitable area，correspondingly accounting for 72． 23% of the total area． (2) the topography，hydrology indices，altitude，and annual average precipitation are the main limiting factors，and significantly restrict the natural suitability of human settlements． (3) the suitable areas for human habitation affected very little by natural and social factors．

Abstract:Using four sets of Landsat TM images of 1990，1995，2000 and 2005 and the Markov model，the changes of land use and structure index were analyzed and predicted in order to improve the understandings of the driving forces for land use change in Changsha City． The results show that during the 30 years from 1990 to 2020 in Changsha City，the information entropy and equilibrium degree of the land use structure increased from 0． 879 3 and 0． 490 7 to 0． 922 5 and 0． 514 9，respectively，while the degree of dominance decreased from 0． 5093 to 0． 4851，reflecting the degree of order in the land resource system decreased． A significant and close correlation was also indentified between the land use structure changes and social economic driving factors．

Abstract:Soil moisture is an important factor for plant growth and development in arid and semiarid areas． We used three methods of drying methods，TDR(time domain reflectometry) and EC-5 sensor to observe soil moisture variations in the Mu Us sandy land． The results show that there was no significant difference in the soil moisture contents measured using the three methods in different layers． The values from the three methods were significantly correlated．EC-5 sensors could be used in observation low water contented soils with a precision level similar to traditional methods like drying and TDR． Furthermore，EC-5 is more suitable in developing an automated soil moisture monitoring network．

Abstract:The optimal deployment scheme based on multi-objective genetic algorithm can provide references for urban sustainable utilization and management of water resources． The optimal deployment scheme for Xining City was established according to the actual situation of water resources，and was optimized by using multi-objective genetic algorithm． The results show in different years with various guarantee rates，the supplies of total and individual water resources reduced substantially after optimal deployment，while the reductions in surface water and groundwater were more significant． The application of the multi-objective genetic algorithm in optimizing water resource deployment showed preferable effects，resulting in reasonable and reliable results．

Abstract:As the remote sensing data collected with Chinese satellite，CBERS-CCD data and its quantitative research and application attracted heavy attentions from many scholars，especially for the restoration and reconstruction of the areas experienced the Wenchuan earthquake disaster． This research chose Sichuan Zipingpu Reservoir area as the study site，and built a new straightforward model，which used an image-based improving method and the general multiple-iterative method to estimate the required parameters，such as atmospheric path radiance，up and down transmittance，and total optical depth，etc． A few detailed comparisons were also conducted in terms of visual quality，statistical characteristics and NDVI changes of the images before and after atmospheric correction． With this developed model，the atmospheric effects of CBERS-CCD data could be eliminated and the image information also has been enhanced． A conclusion can be drawn that this image-based atmospheric correction model is highly applicable and economically effective．

Abstract:A reservoir with branches was selected in Xinjiang Uygur Autonomous Region as the study subject． Based on the analysis of the interaction between branches and the reservoir，this study simulated the temperature dynamics in the reservoir under the scenarios with and without the influence of branches using 3D temperature model． The temperature distributions on reservoir water surface，in discharged water，and in the vertical profiles in upstream front of the dam were compared． The results show that the branches had certain influences on the temperature distribution of the reservoir; under the influence，the water in the bottom of the vertical profile in front of the dam had low temperature，as well as the discharged water from the dam outlet． The large temperature differences were found in the winter． Through shifting the location where the branches merge into the reservoir，the simulation indicated that the influences of the branches on reservoir temperature distribution increased as the merging point moving towards the dam．

Abstract:Based on the data of environment，society，economy，and water resources of Tarim River basin in 2005，we evaluated the water resource carrying capacity of the basin using a variable fuzzy model． The results show that the method identified reasonably the relative degree of membership and relative membership function of the individual index in each index group，and it also determined properly the classes that each sample belongs to by changing the model with its parameters，greatly improving the reliability of the assessment． The water resources carrying capacity of Tarim River basin belongs to the second class，showing a high degree of water resource utilization level． It is important to improve the water carrying capacity by adopting some fundamental measures，which include converting the economic structure from water over-consuming to water saving，balancing water uses among the areas of the upper and lower reaches，carrying out integrated schemes of water exploitation and utilization，and developing a decision-making supporting system covering the whole Tarim River basin．

Abstract:A debris flow prediction model is often a statistical model which mainly uses the information of rainfall as the single basis，resulting substantial inaccuracy and indeterminacy in the forecast． Debris flows occur when the soil mass lost its stability owing to the pressure of surface runoff and the lubrication of the infiltrated water． The saturated soil depth by infiltrated rainfall can therefore be used as the lower boundary of debris flow source to enhance the physical elements of debris flow forecast． We described the working principles and the structure design of the detector for saturated soil depth． The technique was then employed to obtain the depth of rainfall saturated soil in the source of the debris flow． In addition to the real-time rainfall data，the saturated soil depth was used to forecast the occurrence of debris flow． According to the field experiment and the instrument observations，the accuracy of debris flow forecasting can be improved by monitoring the rainfall infiltration depth in soil of the debris flow source．

Abstract:Land use/cover changes(LUCC) have been regarded as a research hotspot in the field of global environment change． Quantitative evaluation on land use change is of great significance for sustainable utilization of local land resources． The Ebinur Lake watershed in Xinjiang Uygur Autonomous Region，as the study area，is a typical area of arid regions． Based on the LUCC data in 1970 and 2009，we used mathematical models and ArcGIS to analyze the change in land use/cover during this time period． The results show that the areas of cropland and construction land increased constantly from 1970 to 2007，with average annual rate of 5． 21% and 5． 62%，respectively． Accordingly，the areas of the other land use types decreased． The transformation between cropland and grassland，and between unused land and grassland were significant． The area of construction land experienced maximum changes and the water area minimum． Specifically，unused land，grassland，and cropland received most conversion areas from the other land use types，and unused land and grassland contributed most areas to the other types．

Abstract:Inter-annual and seasonal characteristics of groundwater table fluctuations in the urban area of Qianxian County，Yangmaowan irrigation area，and Baojixia irrigation area were analyzed based on the groundwater table data collected from seven monitoring wells between 1992 and 2007，along with DEM which reflects the topography and drainage system distribution of the study area． The study area is located in the transition zone from the North Weihe to Guangzhong region． The results indicate that the groundwater table in the urban area of Qianxian County rose at a rate of 0． 31 m/a during the study period． However，the groundwater tables in Yangmaowan and Baojiaxia irrigation areas were declining in the past sixteen years; the groundwater table of Yangmaowan irrigation area declined faster than that of Baojiaxia irrigation area． In wet years，the groundwater tables of the wells that is close to reservoirs rose quickly due to the combined effects of both reservoir recharge and rainfall infiltration． On the contrary，the groundwater tables of the wells that is far from reservoirs rose more slowly as rainfall infiltration was the only recharging source． The irrigation areas had the relatively higher groundwater tables in February and October and the lower ground-water tables in July． Combination of channel and well irrigation is suggested for the sustainable use of groundwater resources in Qianxian County．

Abstract:Heilonggang area is one of the districts that have most serious shortage of water resources in North China plain． At the same time，it is also a major production base for grains and cotton in Hebei Province． Because of the lack of surface water and the wide-spread pollution，the water demand from crops in the district depends only on rainwater and groundwater． In this study，agricultural cultivation structure and water resource distribution were analyzed，and the water demands of different types of crops were also addressed． Furthermore，the supply and demand balance of water resources was evaluated in consideration of cultivation structure． The evaluation result shows that the supply and demand of water resources was generally unbalanced in the district，especially in the north part of the district． Agricultural cultivation structure mismatched with water resource distribution; many areas lack of water resources were cultivated with high water-demanding crops． In order to solve this problem，the agricultural cultivation structure should be adjusted，with necessary enhancement in multi-dimensional technologies of water resource utilization and optimization of water supply system．

Abstract:In order to demonstrate the status and the trend of water environment carrying capacity，the fuzzy matter-element model coupled with entropy weight method was adapted to calculate the proximity between the water environment carrying capacity and standard samples in the area of Muping district，Yantai City from 2005 to 2009． A total of seven indices were selected． The results show that the proximity between the water environment carrying capacity and standard samples were 0． 804 7，0． 684 2，0． 666 7，0． 675 3，and 0． 696 1 from 2005 to 2009，respectively． The water environment carrying capacity were at level Ⅲ in 2006 and 2009，while the other three years were under level Ⅲ，indicating poor water environment carrying capa-city of the investigated area． Furthermore，suggestions were made on improving the water environment carrying capacity and promoting the sustainable development of society and economy．

Abstract:Yachi demonstration Base in Bijie region，where has a karst plateau hilly environment setting with warm and cold temperature ranges，dry springs and humid summers，was chosen as the study area． Based on Spot 5 (5 m resolution) remotely sensed images，the topographic maps (1∶ 10 000)，and the land use map，etc． ，the extent of rocky desertification in this area were interpreted and the incidence of rocky desertification in the different types of land use were investigated quantitatively． It was found that the spatial distribution of different land use types is one of the important factors that lead to different grades of rocky desertification． Shrubs，other forests，low-coverage grassland，mountainous dry land，and unused land contributed a large proportion of the desertified land． In addition to protecting and improving ecological environment，enhancing the productivity of the land and developing the social economy should also be listed as the major objectives in deploying integrated measures for the rocky desertification control．For example，engineering measures like terracing project should be constructed combining with biological measures such as economic trees planting，etc．

Abstract:Based on documented data of 2009，field investigation，and experiments，we quantitatively evaluated the values of dominant ecosystem service functions of urban wetlands in Zhenjiang City of Jiangsu Province，comprehensively using approaches of ecological，environmental and resource economics． The results show that the wetlands possessed large and multi-dimensional ecological service functions with the total value of approximately 3． 14 ×10¹⁰Yuan， of which the direct and indirect use values were 73． 71% and 26． 29%，respectively． In the three major categories of dominant ecosystem service functions，the values of culture-social service function has the largest function value，as high as 39． 18% of the total value，followed by those of the production service function(32． 34%)，and the regulation and maintenance service function(28． 48%)． Meanwhile，the values of tourism and leisure，flood regulation，water supply and rice production summed as 84． 22% of the total value． The value per unit area of Zhenjiang City urban wetland was about 46 times of the global and national average． Specifically，the unit area value of the natural wetlands was estimated as high as 5． 49 × 10⁵Yuan /hm²，much more than that of the artificial wetland (1． 04 ×10⁵Yuan/hm²)．

Abstract:As a case study，the grey linear programming method has been used to analyze the land use structure optimization in Shangluo City in Shaanxi Province． It shows that farmland will still be the main land use type in the next 10 years in this area． The multiple-purposed land use and forestry mixed with cultivation should be promoted，considering multidimensional ecosystem construction and soil，water and wetland conservation． In the process of land use structure optimization，the economic，social and ecological effects of the land use should be emphasized comprehensively with the guarantee of long-term benefits and sustainable development of this area． Scenario analysis method is proved to be a feasible and effective method in land use structure optimization．

Abstract:The triangle model was used to evaluate the efficiency of the land use in Zhengding County of Hebei Province． Based on the relationship among the economic，social and ecological benefits of land use，the triangle model was establish in the Origin software package to assess the land use efficiency in Zhengding County from 1997 to 2008．The results show that the detailed classification and intuitive diagram from the triangle model described effectively the types and trends of land use． The land use efficiency of Zhengding County could be divided into six classes，the land use efficiency of Zhengding County changed from the ecology-lagging unsustainable state to the ecology-leading，societyleading，and economy-leading weakly sustainable state．

Abstract:Based on the year books of soil and water conservations in Gansu Province and the findings of many research projects，the study quantified the effective areas，the runoff reduction coefficients，the sediment reduction coefficients and the production-devotion coefficients of the soil and water conservation measures． Meanwhile，we calculated the economic，social and ecological benefits of these measures． The results show that，in the last 60 years，especially the last 30 years since the economic reform and opening-up，the soil and water conservation comprehensive projects carried out in Gansu Province made remarkable contributions in providing basic platforms for the rural socioeconomic sustainability and reasonable allocations of natural resources． The results also show that the accumulative benefits in terms of runoff reduction，sediment reduction and economic value reached 1． 10 ×10¹⁰m³，5． 90 ×10⁹t，28． 8 billion yuan，respectively，in the last 30 years． At last，the paper provided associated suggestions according to the major problems found in the previous work．

Abstract:Considered the current hydro-ecological conditions on Manas River basin and relevant existing problems，an evaluation index system consisting of three hierarchies and 19 individual evaluation indexes was established． The weight for each evaluation index was allotted based on the analytic hierarchy process (AHP)，and then the evaluation criteria and two-level comprehensive fuzzy evaluation method were deve-loped． The quality of the hydro-ecosystem in Manas River basin was evaluated as an example． The evaluation results show that the factors of hydrologic meteorology and eco-environment dominated the hydro-ecosystem quality in the basin; the memberships of the two categories to the class of very poor were 38． 4% and 47． 0%，respectively． At the same time，social-economic factor was relatively better，as its membership to the class of good was as high as 59． 2%． Overall，the hydro-ecosystems quality of Manas River basin was evaluated as low，which matched well with the fact． This suggests that the evaluation method developed in this study could have extensive application value in the similar areas．

Abstract:Based on the land use data of Hechuan District collected during 2000-2009，the effects of land use changes on ecosystem service values and landscape patterns were studied． The results indicate that the areas of agricultural land and garden land decreased substantially，and in contrast，the areas of construction land and woodland increased rapidly． Meanwhile，the landscape pattern analysis showed that the patch numbers and density were lowered，the degrees of fragmentation and dominance of the landscape were dropped，and the index of diversity and evenness increased during this period． In addition，the total regional ecosystem service values grew from 197 134．6 to 204 620．7 thousand Yuan． The ecosystem service function values dropped slightly in the functions of water regulation，waste treatment and food production，while the functions such as atmosphere regulation，climate regulation，erosion control，soil formation，biodiversity，raw materials，and entertainment，showed significant improvement．

Abstract:The "5·12" Wenchuan earthquake induced a large number of landslides，which had directly threatened the safety of human lives and properties． The old Sanjiadi landslide in Southern Gansu Province experienced largescale collapse in foreside and a long，and through cracks formed owing to the front traction during Wenchuan earthquake，which could seriously jeopardize the safety of 1 732 people of the village on it． It is therefore very important to understand adequately and maintain effectively the stability of the landslide． Based on field investigation，indoor test and related studies on Sanjiadi landslide，the basic characteristics and formation mechanism were elaborated． Assuming different working conditions，the stability and stress-strain features were calculated and analyzed by adopting transfer coefficient analysis and numerical simulation． The results show that the integral stability coefficients of the old landslides ranged 1． 30 ～1． 36，implying a steady state in the normal condition． Under rainstorm and seismic conditions，the stability coefficients of landslide were 1． 02 ～1． 09，indicating an unstable state． Finally，relevant engineering strengthening measures were provided based on the formation mechanism and quantitative evaluation results of the landslides．

Abstract:The cultivated land production factor originally developed by Wackernagel was revised based on the data from the year of 2009． Using the principles and models of ecological footprints，this study proposed a ecological pressure index model and prediction models to calculate the ecological footprint，ecological carrying capacity，and ecological surplus/loss of Xi'an City from 1997 to 2009． The results indicate that from 1997 to 2009，the ecological footprint increased 0．509 7 hm² per person，the ecological carrying capacity 0．152 0 hm² per person，and the ecological pressure index had changed from 1． 45 to 3． 88，indicating Xi'an City had been overloaded heavily and increasingly． In brief，the environment of Xi'an City is ecologically unsafe and its sustainable development could be at risk．

Abstract:Based on calculation，the ecological footprint，carrying capacity，ecological deficit of Yongning County in Ningxia Hui Autonomous Region is 3． 830，3． 376 and 0． 454 hm² per capita in 2006，respectively． The results reveal that the rate of resource consumption apparently exceeded that of resource renewal，imply-ing an unsustainable status．The ecological footprints of the Yongning County were contributed mainly by cultivated land，grassland and fossil fuel consumption． The climbing of animal husbandry and fossil energy consumption was the main reasons leading to increases of ecological footprints． The study also pointed out several effective measures to reduce the ecological deficit，and enhance ecological capacity of the Yongning County，such as improving utilization ratio of fossil energy，decreasing industrial energy consumption，deve-loping circular economy，utilizing renewable energy including solar and wind energy，planting forage，and compressing farm sizes．

Abstract:We summarized the issues found in the reclamation of urban water，and analyzed the major causes of these issues． Based on the connotation of water resource carrying capacity，we also addressed the status and potential contributions of urban reclaimed water in water resource allocation and piloted different ways to utilize the reclaimed water．Considered the policies aiming at constructing a water-saving society fulfilled by Deyang City，the approaches，objectives，measures and significance of urban water reclamation are discussed． Urban water reclamation could solve the issues in water resources such as overcapacity，insufficiency，and the conflicts between demands and supplies of the reclaimed water． The findings of the study could be used guidance for urban water reclamation in achieving the goal of water-saving．

Abstract:Plant species and composition characteristics were investigated in Phragmites communis community and Kobresia tibetica community． The results show that Phragmites communis and Kobresia tibetica were the dominant and the subdominant species in Phragmites communis community，with important values of 0． 434 2 as in sum． Kobresia tibetica was the dominant species in Kobresia tibetica community，with an important value of 0． 187 6． Species diversity analysis showed that in the two communities，the Shannon-Wiener index(H) and the Pielou(evenness) index(J)varied with large amplitudes of fluctuation，while the Simpson(dominance) index(D) showed much less variations．The diversity index was significantly correlated positively with the evenness index and negatively with the ecological dominance index，while not with the species richness index(S)． The H，D，J and S values were not significant different in the two communities，each consisted of 14 species． The similarity coefficient between the two communities was 51． 85%． Thus，the community composition of Phragmites communis community was closely related with that of Kobresia tibetica community．

Abstract:Over years of planting，soil-to-sand ratio and the contents of soil salt and water in the sand fields changed substantially，and the degradation of the sand lands accelerated． This study addressed the mechanism of water-salt variation and summarized the causes of degradation，providing the basis for sand field maintenance． The results show that the practice of cultivation increased soil-to-sand ratio，however，reduced soil water holding capacity，soil water storage，and soil anti-evaporation capacity． The water-salt variation of the sand land was closely related to the length of planting years，gravel cover thickness，diameter of the gravels，location of gravel on the surface soil，and water table depth． To some extent，the water-salt variation has led to the degradation of the sand fields．

Abstract:The impacts of land use types on water quality of highland lakes were investigated and modeled based on the data collected from the nine plateau lakes in Yunnan Province． The Kuznets curve analysis was used to simulate the time series of the dynamic changes of land use intensity and water quality． The results indicate that the contents of phosphorus in the water samples from the lakes to some degree correlated negatively with the areas of cultivated land，gardens，and wetlands，and positively with the areas of woodlands，grasslands，and construction areas． In contrast，the contents of nitrogen in the water samples from the lakes correlated negatively with the areas of grasslands，cultivated lands，gardens，and wetlands，and positively with the areas of the construction lands． Overall，the pollution indices were negatively correlated with the areas of gardens and cultivated lands，and positively with the area of the construction lands． The temporal analysis indicated that the basins of Dianchi Lake and Lugu Lake were in a status of wellbeing，the basins of Yangzonghai，Fuxian，Xingyun，Cheng Lakes were in a status of crisis，and the basins of Erhai and Yilong Lakes were in a status of converting from crisis to wellbeing．

Abstract:The species diversity of plant communities was investigated along the Qinghai-Tibet railway． The results show that the species richness index(S) increased and then remained steady． The Shannon-Wiener index(H)，Pielou (evenness) index(J) were still rising gradually，however the Simpson (dominance) index(D) decreased．The S index value determined to some degree the H index． In the communities with similar S indices，the plant communities with higher J indices were often dominated by the species with higher D index． In the communities experienced secondary recovery on the permanent tundra，the S index，H index，and the J index showed a same tendency:ascending and then descending gradually with increasing distances to the railway． The maximum values of the indices were found at the distance of 75 m from the railroad，and the minimums were found at the distance of 300 m． This indicates that plant communities experienced gentle disturbance showed higher species diversity and become more stable after secondary recovery． The S index changed accordingly with the variations of elevations，as shown by the relationship between the S index and environment factors．

Abstract:The distribution patterns of soil microorganisms in five plant communities including Phragmites australis，Boraginaceae，Limonium bicolor，Z． Macrostachys and Suaeda glauca were studied at Wudi shell bars in Shandong Province． The results show that the orders of magnitude of bacteria，fungi and actinomycetes were 10⁴，10⁴，and 10²，respectively，in all vegetation communities． The contents of bacteria，fungi and actinomycetes in August were approximately 0． 45，6． 16，and 3． 61 times higher than those in June，respectively． In the soil layer of 0-30 cm，the contents order of microorganisms in the vegetation communities followed a descending order as Limonium bicolor ＞ Z．Macrostachys ＞ Suaeda glauca ＞ Boraginaceae ＞ Phragmites australis． Bacteria dominated in Z． Macrostachys vegetation communities，while the majority of microorganisms were fungi and actinomycetes in plant communities of Phragmites australis and Suaeda glauca． The vegetation species and microorganisms were linearly correlated，with a highly significantly coefficient (p ＜0． 001)．