Abstract:Compared with other large reservoirs in China and abroad,the hydro-fluctuation belt of the Three Gorges Reservoir is characterized with high annual hydro-fluctuation,heavy waves caused by busy shipping in the main stream and a large area of fertilized cultivated land.After filling of a reservoir,great geo morp hologic changes should occur on the bank slope and final stable slopes has following three types:silting beach slopes,eroded bedrock slopes and eroded earth slopes.Geomorphologic evolution processes on bank slopes of the hydrofluctuation belt can be divided into three stages of severe erosion,general stable and gradual silting up.Vegetation mediation on the bank slopes should be seriously affected by soil losses during the geomorphologic evolution processes after reservoir filling.Little researches have been done on geomorphologic evolution of the bank slopes in the hydro-fluctuation belt of the Three orges Reservoir.Little attention has been paid to the geomorphologic evolution of the bank slopes in the existing key research projects on ecology and environment remediation in the hydro-fluctuation belt of the Three Gorges Reservoir.From the view of the geomorphologic evolution of the bank slopes,suggestions on research and remediation of the ecology and environment in the hydro-fluctuation belt andon adjustment of reservoir operation scheme are also proposed.

Abstract:Based on questionnaire survey and model analysis,peasant households attitude and behavioral choice and the main factors of households landuse decision-making after the grain for green program(GFGP) were studied.Results show that,in samples,different households have different behavioral choices after expiration of GFGP.Five main factors of households landuse decision-making were proposed through Logit model analysis and the incidence of each factor was diversified.Two conclusions were drawn as follows:firstly,households attitude and behavior were obviously induced by policy and secondly,preferential policy was important to consolidate achievements of GFGP.

Abstract:Hydropower station construction in Southwest China and Yunnan Province has accelerated noticeably recently owing to the dominant position of hydropower development in China's energy development.But it also has prominent impacts on the ecological environment.Considering the construction features and man made soil and water loss,this article proposes that the“three(water,electricity,and gas) available and one flat(construction site flat)”stage and the time before dam pouring are the cxitical period of s oil and water loss.Dumpling piles and construction roads are the main sources of soil and water loss.Several control mean ures are also proposed,such as proper dumpling pile location,foundation treatment,runoff exhaust,spoil block,spoil platform,and slope management,as well as reasonable water cutoff and drainage on construetion roads,excavated slope stabilization,embankment protection,protection of lower slope,and appropriate vegetation.

Abstract:The recognition of present agricultural status is helpful to realize the sustainable development of agriculture.The appropriate assessment system of agricultural sustainable development of 14 karst counties in Chongqing Municipality is studied based on the characteristics of the karst eco-environment.By factor analysis method,a mathematic model evaluating the quantitative level of agricultural sustainable development is established.Regional economic level,population stress,abundance of land resources,agricultural produetion pattern,and karst rocky desertification are found to be the key factors.Agricultural structure should be adjusted,pattern of agricultural industries should be optimized,soil and water pollution should be controlled,and scientific agricultural development plans should be set down.

Abstract:Based on the analysis of the fragile ecosystem characteristics and its causes in the hilly region,Taihang Mountain,this study suggests that developing ecological agriculture is an important way to solve environmental and economic problems and fulfill regional sustainable development.In addition,according to different forms of ecologic land suitability,we puts forward corresponding development patterns of ecological agriculture and its key techniques,such as ecoeconomy protective forest model,highly effective and intern sive ecological agriculture model,the model of comprehensive control of ecological environment,ecological homestead model,agricourism model,and plant resource diversity conservation model.We also propose that the key step for realizing sustainable agricultural development is to restore and maintain bi

Abstract:The variation of the amount of hybrid sweet sorghum with harvest by stages,multiple crapping of wheat stubble,and usual planting with different kinds of fertilization was studied.Results showed that for hybrid sorghum,for the more favorable combinations,the yield of correlative land was more than 59.6 t/hm².Under the same condition,the harvest by stages,which provided higher yield and more fresh and tern der plant,showed the more favorable effect than usual one-step-harvest,and one of the stage harvest combnation provided the highest yield among the ten combinations of different kinds of fertilization and different plant populations.It is operable to plant sequential cropping hybrid sweet sorghum in wheat stubble in the chilly Heilongjiang Province.The best combination of fertilizer and plant population,of which yield coukl reach 31.3 t/ hm²,provided 9.3% and 8.3% daily yield incxease of fresh grass more than usual planting and harvest by stages,respectively.Considering that the cultivated area of wheat in Heilongjiang Province was almost 200000 hectares,multiple crapping of wheat stubble would produce 6000000 ton fine quality fresh forage,which can not only take advantage of the limited resources of light and temperature and reduce soil and water loss,but also promote the development of animal husbandry.

Abstract:The 8 year implementation of the policies of converting cultivated land into forestland/ grassland in Wuqi County has showed considerable effects.The environment of project area is improved,the integration production capacity of agriculture is enhanced,and farmers’income is raised through land subsidy.Furthermore,the practice in the county may be the prelude of a formal system of ecological compensation toward Chinese farmers.However,there are some problems in practice.For instance,the distribution and plant structure of converted lands are not in an optimal state,the efficiency of stock raising sustained by grass resources develops slowly,and the implementation of policies lacks necessary flexibility.This paper suggests that the policies should be further improved though enhancing the guidance of landuse plan,confirming the bound of converted land reasonably,and optimizing the standards of land subsidy according to the principle of ecological compensation.Moreover,boosting reform of landproperty right,promoting reasonable land circulation and its scale management,and developing subsequent agricultural industries are also the urgent affairs.

Abstract:The study was conducted in Niugutu small watershed,Horqin Inner Mongolia.The comprehensive eco-economic model was applied to the works on soil and water conservation of the study watershed,combined with watershed management and incorporation of regional characteristics and market information.The plan and the specific measure of the comprehensive eco-economic mode construction were expounded,and its benefits was analyzed.The results show that the regional ecological environment has been improved and soil erosion has been effectively controlled,which lead to the considerable development of regional economy.The study is an attempt to explore the comprehensive eco-economic management model of soil and water conservation in the earth-rock mountainous areas of Northern China.

Abstract:By taking a peasant household in Duicha Village,Mizhi County of Shaanxi Province as an study object,eco no mic efficiency,ecological benefits,and social efficiency from the "quaternity”mo de of ecolo gy,agriculture,circulatio n,and economy are analyzed.Promoting the methane is found to be the link of ecological agriculture circulation economy.The measure is of benefit to solve some problems existed in agricultural production,such as low agricultural efficiency low farmer income,and environmental pollution caused by long-term planting and cultivation separation and energy use and environmental protection separation.The study may provide a reference for the development of countryside ecological agriculture circulation economy.

Abstract:The assessment of river health status is the base of stream restoration and management.Four assessment methods of stream health status and application procedures of the RBP from American,the ISC and GRS from Australia,and the RCE from Sweden were introduced.Objects,index selection,standard enactment,and result presentation of the four assessment methods were compared.The advantage and disadvantage of different assessment indexes were discussed.The methods were assessed from seven aspects.Results from the study may offer a reference for the assessment system of stream health status in different areas of our country.

Abstract:Lishui River watershed is suffering from the most serious soil and water loss among the four rivers.Based on the principles of soil and water conservation regionalization,this paper carries on the soil and water conservation regionalization in Lishui River watershed using the principal component analy sis and cluster analysis.Results show that Lishui River watershed〔an be divided into the four areas of soil and water cornnervation.They are the comprehensive management area of agriculture,forestry,and herd with the severester crsion in Sangzhi mountains,the closing managementt area with severe erosion in Zhangjiajie medium mountains,the comprehensive management area of agriculture,forestry,and herd with moderate erosion in Shici lower mountains,and the comprehensive management area of agriculture with slight erosion clawn stream plains and hills.For all the advantages and disadvantages in the areas,the paper configures some comprehensive management models on soil and water conservation and presents some suggestions for sustainable development of the region.

Abstract:Taking Zhaozhuang Village of Yan’an Cty in the typical loess hilly and gully area as a study area the landuse change from 2000 to 2006 was analyzed.According to coefficients of ecosystem service value (ESV) by Xie Gaodi et al.,the ESV of landuse system was estimated and the coefficient of sensitivity way also analyzed.Results indicated that landuse of the study area changed to some extent during the past 6 year and decreased farmland and increased unused land were the main types.The total ESV decreased by 329 200 and its change rate was 1.86%.The ESV s of unused land residential-co nstructed land,forest land and shrubby grassland increased,while the ESV s of farmland,orchar,and water area decreased.Eight types of ecosystem service functions were decreased,while recreation and culture increased.The analysis of the coefficient of sensitivity indicates that the coefficient of ESV adopted is inelasticity,the result is reliable and the ESV coefficients are suitable.Landuse structure should be pertinently adjusted according to changing characteristics of ESV.

Abstract:By using the 1∶100 000 landuse vector data in the three periods of the middle 1980s,1990s,and 2000 which are provided by Data Center for Resources and Environmental Sciences,Chinese Academy of Sciences,and by taking GIS as charting and analysis method,the relationship between the space and time changes,the shape characteristics of urban land expansion,and the pop ulation and economics development in Tianjin City were analyzed,Such indexes as urban land expansion velocity and intensity,centre coordinates,compact ratio,fractal dimension,and elasticity coefficient were used in the analysis.It was revealed that the spatiotemporal variation of Tianjin urban land from middle 1980s to 2000 was obvious and that the Tianjin northwest southeast axial and the coastal axial were the mostactive expansion parts.The construction land expansion has been transforming to the irrational direction.The area—GDP elasticit y coefficient was raised and the annually averaged change ratio of economy exceeded far from that of urban expansion.Finally,the brief effect of urban expansio n was the lost of cultivated land and other land resources around the city.The contributio nof cultivated land to the overall urban expansion area was largest and the contribution of other lands such as forest land,grassland,water area,and not using land was second.

Abstract:Soil erosion and redeposition may result in redistribution of soil carbon in terrestrial systems.However,limited information is available about transfer and redistribution characteristics of various soil organic C in the processes of the erosion and redeposition.A representative erosion deposition landform,consisting of strongly eroded zone,slightly eroded zone,slope depositional zone,and bottom depositional zone,was selected to sample four soil profiles for studying the spatial variation of various organic carbon pools in different landform positions and exploring fate of various organic C in the processes of soil erosion deposition.Results showed that intrinsic characteristics of various organic C greatly affected their transfer and distribution behaviors.Contents of total soil organic C and its components increased in the ascendant order of strongly eroded zone,slightly eroded zone,slope depositional zone,and bottom depositional zone.Total organic C content of soil profiles in the eroded zones decreased significantly along with sampling depth,meanwhile those in depositional areas kept relatively high organic C in all sampling depths,even at the deep layer.Black C is the most mobile form of soil organic C and it tended to be accumulated in the soils in bottom depositional zone of the continuation landform.Because of being buried or physically protected from decomposition in the depositional zones,organic C in the zones was C sink.

Abstract:The spatial distribution patterns of nitrate nitrogen (NO₃^-—N) and ammonia nitrogen (NH₄⁺—N)in typical Calamagrostis angustifolia wetland soil s of Sanjiang Plain were studied by Geo statistics method.Results showed that the variability of NO₃^-—N and NH₄⁺—N contents in different soil layers had significant difference,with the order of NO₃^-—N > NH₄⁺—N,and the reasons were mainly correlated with the differences of their physical movement characteristics.Further analysis indicated that the differences of NO₃^-—N and NH₄⁺—N contents in different soil layers or in same soil layer were much significant ( P < 0101).The distribution of NO₃^-—N and NH₄⁺—N contents in different soil layers had significant spatial structure,which accorded with different semivariogram models.The structure factors had significant effects on there spatial variability,while the effects of random factors were relatively less.Microphysiognomy characteristic was an important random factor to induce spatial heterogeneity,while water condition and soil type were two important structure factors.The maximum spatial variability of NO₃^-—N and NH₄⁺—N contents in different soil layers were observed in the direction leaning to the depression center.In addition,the studies also indicated that water condition was the main reason to induce the lower NO₃^-—N content zones to be formed in the lower hypsography of depression,while the alternation of dry and wet was the import reason to inducet he higher NH₄⁺—N content zones to be formed in the lower hypsography of depression.

Abstract:Effects of Caragana microphylla communities with different ages on protection and improvement of soils were studied.Results showed that with establishment and development of vegetation,soil physical and chemical characteristics of C.microphylla communities were improved obviously and there was a positive correlation between soil improvement effects and restoration time.Porosity and percentage of tiny sand (0.05～0.1 mm) and clay particle ( < 0.05 mm) increased,bulk density of top soil (0—10 cm) decreased,and saturated water holding capacity improved.The co ntents of organic C,total N,total P,alkaline N,available P and available K increased to some extent,especially in the topsoil,and C.microphylla exhibited a significant enrichment effect on higher nutrients under their canopies.

Abstract:Waste soil and residue induced by project construction is one of the main ground materials.Based on field scouring experiment,the processes of runoff and sediment yield on waste soil and residue in the Banduo hydropower station project area in the Yellow River were studied and following results were obtained.(1)Under different flow rates,runoff yield varied with souring time and the relat ionships can be described by power equations.Runoff yield changed great ly in initial 5 m in,then changed slowly,and tended to be steady eventually.(2)Under different flow rates,sediment yield decreased with souring time and the relationships can be described by logarithmic equations.(3)Under dif ferent flow rates,sediment concent ration varied with so uring time and the relationships can be described by logarithmic equations.The variations for different flow rates had the same trend,basically.(4)Depth of single runoff yield and modulus of single sedi-mentyield increased with different flow rates and can be described by logarithmic equations.The averaged sediment concentration varied with so uring time and the relationship can be described by a parabola equation. Critical flow rate was found to be 7.17 L/min.(5)The relationship between depth of single runoff yield and modulus of single sediment yield showed a positive correlation.Modulus of single sediment yield increased with depth of single runoff yield and the relationship can be described by a logarithmic equation.

Abstract:Litter s'reserves,decomposition intensity,and water holding ability of four kinds of natural secondary forest in Simian Mountain,the upper area of Three Gorges Reservoir were studied.Results showed that the litters'reserve of broad leaved forest was 107.09 t/hm²,which was the highest among the four kinds of forest litters,and it was followed by co nifero us & broad leaved mixed forest(70.18t/hm²)and coniferous forest(66.65t/hm²).The litters'reserve ofPhyllostachys pubescensforest was the worst,which was only 35.37 t/ hm².The litters'max water holding capacity and water holding ability of coniferous &broad leaved mixed forest were the best among the four kinds of forest litters(89.95 t/hm²,2.25);those of broad leaved forest was second(67.33t/hm²,1.89);those of coniferous forest was third(39.83t/hm²,1.66);and those ofPhyllostachys pubescensforest was the lowest(28.07 t/hm²,1.85).In terms of litters'water holding characteristic,forest hydrological effects of coniferous&broad leaved mixed forest were the best among the four kinds of experimental natural secondary forest,and the effects of broad leaved fo rest were better.The effects of coniferous forest andPhyllostachys pubescensforest were poor,which were not suitable to be popularized in the vegetation construction for soil and water conservation in the area.

Abstract:In order to analyze the spatial pattern of soil seed bank and its relation to environmental factors in the lower reaches of Tarim River,20 sampling plots were established.Seedling germination experiment was carried out and ordination technique(canonical correspondence analysis)was used in the study areas.Results showed that there were 16 species,belonging to 7 families in soil seed bank,among which tolerant-drought and salinity species were dominant.Most species occurred infrequently and soil seed bank density was lower compared with other desert regions.Groundwater depth,soil moisture content,electric conductance,pH,vegetation coverage all influence the distribution of soil seed bank.The relatio nship among the first axe of the CCA,groundwater depth,standing vegetation coverage,and soil moisture content were significant,indicating the role of water availability factor.The relationship between the second axe of the CCA and the electric conductance was significant,indicating the role of salinity factor.Based on the above five environmental factors,16 species of soil seed bank were divided into four groups.

Abstract:Xinjiang is a large district suffering from soil and water loss in China,but soil erosion processes in the region have not yet been under stood deeply.Taking San'gong River water shed in Fukang City,Xinjiang Wei Autonomous Region,as an example,a preliminary study for the distribution characteristics of waterstable aggregate content and its influence factors was performed to provide an important basis for soil erosion control.Soils of 0-20 cm and 20-50 cm on a typical hilly slope,slopes of different gradients,and vegetation converage of different degrees were analyzed.Results showed that the dist ribution of soil water stable aggregates in the small watershed had the following characteristics:it had a decreasing tendency from surface down to bottom in the same soil profile;on the same slope,it had a increasing tendency from top to bottom;and on slopes of different gradients,it had a decreasing tendency with slope increasing.In terms of the water stable aggregate content under vegetation coverage of different degrees,landuse was in the descendant order of sloping cropland

Abstract:Based on fixed field observation for five typical landuse modes,this paper analyzed the effects of different landuses on its rainfall utilization and water balance.The main results were reported as follows.(1)The difference laws of steady soil water consumption in grassland and a higher ability in sufficient use of water stored in deep soil layer in tea garden and the restoration area showed that the characteristics of soil water utilization in different landuse patterns were different with different seasons and soil layers.(2)Evapotranspiration hold more than 83%of input(rainfall),which was the most important output part of water balance in 100 cm plough layer.Evapotranspiration on cropland was the lowest and runoff on it was the highest,but those in the restoration area were reverse.(3)An optimal model of rainfall utilization on sloping land in red soil region must be constructed for reducing surface runoff and improving the utilization rate of rainfall,so the compound management of cropping forestryher bage and the tillage methods of broad base terracing would be the best choice.

Abstract:By using the combined grid and line method in vegetation investigation,vegetation succession in the hill and gully area of western Shanxi Province was studied by a case study of Tuqiaogou small watershed in Fangshan County of Shanxi Province.Results showed that Chinese pine and silver chain(importance value:117.34 and 69.96,respectively)are predominant species of the tree layer in the area.Lespedeza,C.microphylla,and seabuckthorn(importance value:169.45,74.05,and 36.92,respectively)are predominant species of the shrub layer.The herblayer is made of composite and gramineous plants(importance value:126.18and 82.63,respectively).Analysis of comparison and clustering showed that community types are pine cluster and lespedeza cluster in Tuqiaogou small watershed.Vegetation succession list is from bare groud,grassplot,shrub,pioneer trees to co nifer.Succession direction of the whole watershed is toward the silver chain community,Chinese pine community,elmcommunity,arborvitae community,and elmsilver chain mixed community.

Abstract:Converting cultivated land into forestland is an important way for the reconstruction of degraded ecosystem.Soil hydrological and physical properties on 12 converted lands in Northwest Guangxi Province after 3 year reconstruction were observed.Results showed that the averaged soil densities in different soil layers(0-20,20-40,and 40-100 cm)were 0.824~ 1.256 g/cm³,which increased by 2.4%~ 4.4%compared with cropland.Soil density within 20 cm of the surface soil reached a significant level.The averaged soil non-capillary porosity,total porosity,and ventilation were 1.1%~ 21.3%,52.4%~ 59.8%,and28.3%~ 35.7%,respectively.Soil non-capillary porosity within 20 cm of the surface soil reached a significant level.The averaged capillary porosities were 38.5%~ 41.3%,which increased by 5.2%~ 7.6%compared with original farmland.The maximum water holding capacity,the capillary water holding capacity,and the minimum water-holding capacity in the 1m layer were 43.0%~ 58.3%,37.0%~ 48.4%,and 30.5%~ 38.2%,respectively,which had no significant differences.The effective storage capacities in the 1m soil layer on converted farmland were 1652.6%~2294.3t/hm²,which increased by 1.9%~ 5.9%compared with cropland,but the differences were not significant.

Abstract:Soil water holding and infiltration parameters were measured in the research on soil hydrological processes for four different plantations,which wereCunninghamialanceolata×Pinusmassoniana,Lithocarpusglaber×Schimasuperba×Cinnamomumcamphora×Liquidambarformosana,Lithocarpusglaber×Schimasuperba,andCunninghamialanceolata×Pinusmassoniana×Schimasuperba,in Simian mountain of Chongqing City.Results indicated that the saturated soil water holding capacity in mixed broadleaf conifer forest was the maximum of 314.98 mm;broadleaf forests,301.26 mm and 290.26 mm;and coniferous forest,the minimum of 237.94 mm.The values were 44.93%,38.61%,33.72%,and 9.48%higher than those in barren land,respectively.Soil infiltration rate inLithocarpusglaber×Schimasuperbabroadleaf forest was maximum,with the initial rate of 25.35 mm/ min,the stable rate of 3.97 mm/ min,and the averaged rate of 5.48 mm/ min.The grey relational grade analysis indicates that the two different mixed broadleaf forests are able to adjust and conserve maximal daily rainfall.Broadleaf forest mixed by Lithocarpusglaber×Schimasuperba×Cinnamomumcamphora×Liquidambarformsana has excellent soil water holding capability,while broadleaf forest mixed byLithocarpusglaber×Schimasuperbahas strong soil infiltration efficiency.

Abstract:The plant communities species diversity of alpine-cold grassland in different elevation gradients was studied.Regression analysis was used to study the relationships between 4 diversity indexes and 14 soil factors.Results indicated that total salt content,HCO₃^-,Ca²⁺,available nitrogen,pH,and soil moisture content were correlative to species diversity significantly(P<0.05).The relationship among diversity,total salt content,HCO₃^-,Ca²⁺,available nitrogen,and soil moisture content was best fitted by binomial model.The relationship between pH and richness index was best fitted by linear model.The relationship among Shannon Wiener index,the total salt content,Ca²⁺,and pH was best fitted by binomial model.The relationship between soil moisture content and Shannon Wiener index was best fitted by linear model.The results showed that diversity did not have a simple negative or positive relationship with the soil factors.

Abstract:In order to study the effects of oil contaminated soil on the germination and growth of plant seedling,crude oil and fluvo aquic soil in the oil extraction area of Zhongyuan Oil Field were selected to study seed germination,individual height,and fresh weigh germination under the condition of various oil concentration of soil by the pot planting experiment.Results show that the variation of oil concent ration of soil has different effects on each index of ryegrass,tall fescue,alfalfa,white clover,and red clover growth.Crude oil rest rains growth of them when its content is high.All treatments have less effect on seed germination,in dividual height and fresh weight of sunflower,cotton,Bermuda grass,and sorghum sudanense.They can grow on oil-contaminated soil.Bermuda grass can be fit to grow on the crude oil-contaminated soils by it self and it is a plant with the biggest experimental potential to phytoremediation of oil-contaminated soils in this experiment.

Abstract:Through the located runoff plot observations in the Heaven Lake Nature Reserve of Xinjiang Wei Autonomous Region,soil erosion processes on sloping grassland were investigated.Results show that firstly,runoff depth increases with the increased rainfall amount,rainfall intensity,and gradient.The relationship between sediment and rainfall intensity is apparent.Secondly,grass has great influences on sediment yield on sloping grassland.Thirdly,the relatio nship among runoff depth,rainfall amount,rainfall intensity,and gradient can be well described by multiple linear regression function.Lastly,the relationship among sediment,soil bulk density,runoff depth,rainfall amount,and rainfall intensity can also be well described by multiple linear regression function.

Abstract:Soil moist ure of soil profile(0—210 cm)in a black soil during crop growth(May to September)was monitored.Distribution characteristics of soil moisture of soil profile,seasonal dynamic variation,and variation coefficient were analyzed.Results showed that the variation of soil moisture in the soil profile had an "increasing-decreasing-increasing"trend with soil depth increasing in observation period.Soil moisture in each layer presented a"decreasing—increasing—decreasing"trend with time increasing and it was closely related with rainfall and crop growth.The acute change layer was not found in observation period.The biggest variation coefficient of soil moisture was observed within 10 cm of surface soil and the variation coefficient decreased with soil depth increasing.

Abstract:The longterm fertilization experiment was carried out to analyze the effects of longterm fertilization on various active organic matters by determining concentrations of active organic matter in two soil layers(0—20 and 20—40 cm).Four treatments of no fertilizer(CK),single application of chemical fertilizers(NPK),single organic fertilizer(M),and organic and inorganic fertilizer application(MNPK)were arranged.Soil active organic matter was measured with oxidation of three level concent rations of KMnO₄,namely,33,167,and 333 mol/ L and thus three fractionations were high active organic matter(HAOM),middle active organic matter(MAOM),and active organic matter(AOM).Results showed that longterm application of organic manure or fertilizer can increase soil organic matter content,especially for organic and chemical fertilizer and single organic fertilizer treatments.Organic matter content in 0—20 cm soil layer was generally higher than that in 20—40 cm soil layer and fertilization caused an increase in organic matter concentration mainly in 0—20 cm soil layer.There were significant differences among fertilization modes,fertilizer types,and soil layers.In addition,there were significant relationships among the various active organic matters.The correlation coefficient for HAOM and MAOM was 0.819*;for HAOM and AOM,0.812*;and for MAOM and AOM,1.000**.Accordingly,MAOM and AOM were most closely connected among the three types of organic matter.

Abstract:Typical communities and species diversity on the different types of vegetation surrounding the region along the desert-crossing highway in Hangjin County of Inner Mongolia were analyzed by using the method of road inspection and typical investigation.Results showed that there were 16 communities and 37 kinds of plants in the region,which belongs to 14 families and 30 genera,respectively.They mainly included sand plants,salinization plants,and low-wetland plants.Shrub)grass communities were dominant and had a tendency of evolutionin succession,such asSalix psammophila,Hippophaer hamnoides,andTamarix chinensis.

Abstract:In this paper,mica powder and acrylic monomer were selected as raw material and made it into a new water absorption polymer.To explore the basic water absorbing characteristic,its influences on the potassium supply of soil was studied by anindo or training experiment.Results showed that the absorbing char-acteristics of the cross-linked substance of mica powder and poly acrylic acid is desirable,especially the strong saline absorption.When applying it into soil in low dose,the cross-linked substance of mica powder and polyacrylic acid can improve the potassium supplying strength of soil and in high dose,it can raise the buffer capacity of soil potassium.

Abstract:Distributions of heavy metal(Pb,Cr,Cu,Ni,Mn,and Zn)speciation in surface sediment of the Wei he River(Xianyang Section)were studied by using the modified four step sequential extraction(BCR method).Results show that Cr,Ni,and Zn mainly occurred as residual fraction,which were 97.91%,66.36%,and 73.68%,respectively.Pb and Mn indicated some bioavailability and potential ecological risks because the extraction of acid was 27.66%and 38.49%for Pb and Mn.The total"labile"f ractio natio next racted for heavy metals was highest in the upper confluence of Fenghe River and Weihe River,then higher in the third bridge of Weihe River,and the lowest in the downstream confluence of Fenghe River and Weihe River.

Abstract:4 flood level marks on the cliff faces were observed in upper and lower Jingcun hydrologygauge station in the middle reaches of Jinghe River,Binxian County.Through local interview and consult data,the ages of the 4 flood level marks were determ ined accurately.Then their peak discharges were quantitatively figured out by the hydrology principle of f lood leve-l discharge and slope-area m et hod and t he erro rs were estimated to be 1.42%~ 4.21%and-2.13%~ 3.16%,respectively,compared to the f lood data observed.The result showed that the flood level marks on the cliff faces in river channel could check the flood data observed and the extreme floods could also be figured out by the flood level marks in the drainage basin where was short of the flood data observed.

Abstract:Annualized Agricultural Non Point Source model(AnnA GN PS),a continuo us simulation model at water shed scale,simulates surface water,sediment,nut rients,and pesticides leaving the cells and their transport through watershed.The Daning River water shed is selected as a study case.The characteristics of sediment delivery are studied based on landuse,soil,topographic data,and eight year climatic data from 11 meteorological stations.Averaged annual sediment load is 1.25×10⁶t/a at the Wuxing station,rapidly rises up to 1.81×10⁶t/a at the Dachang station,and reaches 1.95×10⁶t/a at the water shed outlet.Xixi River,one of the biggest tributaries in the Daning River watershed,has the largest volume of water discharge up to 20.97%of the total at the watershed outlet.Dongxi River,the second tributary,has the most sediment load up to 26.88%of the total at the watershed outlet.In addition,the area of left bank in the middle watershed(from Wuxi station to Dachang station)is another large sediment source.The sediment delivery ratio(SDR)of the whole watershed is 0.30 in accordance with published references.Viewed from four main stream stations,i.e.Do ngxi river outlet,Wuxi station,Dachang station,and the watershed outlet,the SDR is positively correlated with the watershed area.However,the relation is not significant in the six tributaries owing to the high variatio ns of drainage area,slope,runoff rainfall facto rs,land use/ land cover,etc.

Abstract:Based on the data obtained in artificialRobinla pseudoacaciaandCaraganakor shinskiiwoodlands of Ya'an City,Ansai County and Wuqi County on the hilly-gulled area of the L oess Plateau,soil anti-erodibility of woodlands was studied by choosing natural restoration lands and slope croplands as controls and comparing the 5 anti-erodibility indexes(>0.25 mm water-stable aggregates,>0.5 mm water-stable aggregates,mean weight diameter,aggregation status,and degree of aggregation).By comparative analysis of t he 5 indexes,soil anti-erodibility of artificial woodlands is much better than slope croplands,but not better than natural restoration lands.This is more significant in Ansai and Wuqi.Soil anti-erodibility increases with increasing woodland age and then tends to besteady.All the plots in the three areas can be clustered into three kinds based on the 5 indexes and the same results obtained as the above comparative analysis.It is suggested that natural vegetation restoration without disturbance could be the more adaptive type of vegetation restoration and the bett er measure for soil erosion control in the hilly-gullied region of the Loess Plateau.

Abstract:The correlation of extreme rainfall to eroded sediment transport is analyzed in detail based on the data of debris flows observed from 1965 to 2007 in J iangjia Ravine of Xiaojiang River basin and t he daily rainfall data collected from 1970 to 2005 in Huize station in the upper reaches of Yangtze River.Results from the analysis indicate that extreme rainfall events and rainfall amount in summer have a notably increased trend in the region since 1990s and M—K test presents a notably increased trend(confidence interval of 95%).The character has a close relation with the tendency of increased sediment transport in debris flows in the Jiangjia Ravine.

Abstract:The characteristics of soil and water loss in block-type engineering and line-type engineering were analyzed by making soil and water conservation plan for some large and medium-sized projects.The analyses indicate that the quantity of soil and water loss in the construction period is 85%of the total soil and water loss.The quantity of soil and water loss of perunit area in block-type engineering is 86.61 t/ hm²and the quantity of soil and water loss perunit area in line-type engineering is 202.40 t/hm².The quantity of soil and water loss and the area in the construction period of block-type engineering have a linear relation(R²=0.9497).The relationship betw een soil and water loss and the area in the construction period of line-type engineering is logarit hmic(R²= 0.8003).Furt hermore,some cases in the study show that it is need to calculate the reduced quantity of soil erosion by choosing the rate of reduced quant ity of soil erosion for forestry and grass measures.

Abstract:With the advancement of industrialization and urbanization,it is urgent to reinforce them anagement and prevention as well as control of damage to water environment function on lake wetlands.The article establishes the monomial and comprehensive loss rates by water pollution based on the calculation model and the original monitoring data from 1997 to 2006,through calculating the dynamic diversification of pollution loss rate of Yuehai wetland and analyzing its degree of environment function damage.Because the main source of Yuehai wetland is the withdraw nagricultural water,the total P,the total N,and BOD5 become the main pollutant.The index of permanganate is always the main factor of function damage of agricult uralirrigation.From calculated result of the comprehensive loss rate,annual pollution loss rate in fishery,habittion,and agricultural irrigation functions on Yuehai wetland are generally steady.However,for drinking water and swimming functions,annual pollution loss rate varies severely on the whole.

Abstract:The joint effect of earthquake and rainstorm is the extreme condition which causes landslide in nature.The current co des to evaluate the impacts of both earthquake and rainstorm on slope stability are just a simple addition of the two factors.By using the GEOSLOPE software and employing dynamics element infinite and limit equilibrium theory,this paper evaluates the stability of the typical slope sites along the Sichuan—Tibet highway and Xichang—Panzhihua freeway under the coupling of earthquake and rainstorm,in order to find the difference of simple addition and the coupling analysis of earthquake and rainstorm,and also evaluates the applicability of regular computational methods.Research has found that the coupling of earthquake and rainstorm has more serious impacts to slope stability than the simple addition of impact of earthquake and rainstorm alone.

Abstract:Digital Elevation Model(DEM)is the essential data for research on Terrain and SRTM data are the public free access dataset with 90 m resolution.Topographic representations of SR TM and DEMs generated from 1∶50 000,1∶100000,and 1∶250 000 topographic map sare compared and the surface and derived topographic parameters including slope,curvature,streams,and slope length are ext racted.Results show that SR TM data p resent less terrain details on the table capacity than the 1∶50000 topographical map,even not better than the 1∶10000 topographic map,but better than the 1∶250000 TINDEM.

Abstract:Index statistic on deep borehole prospecting test and verification of various in situtests in Lixigo uindicate that deep part survey index of high tailing dam is greater than shallow part.Under the circumstance of the same spatial location and the same depth of piling dam body,gravity index increases significantly with time.Physical indexes are selected by the early,middle,and late stages in the stability analysis of high tailing dam for the same material(medium sand silt).Improved drainage structure method is adopted to simulate densely dist ributed drainage holes.By using complex three dimensio nal seepage soft ware(SP GCR 3.FOR),the inverse analysis of sat uration line and seepage discharge is made for a status dam of a height of 135 m.According to the fitting inverse analysis of drainage and seepage facilities,the mat hematical model which conforms to the reality is obtained.The outcome from the analysis mentioned above coincides with the groundwater level in t he survey section and observed seepage discharge,with the error less than 13%.Accordingly,the seepage model and stack pile sedimentary seepage parameter are found,which can be applied to the analysis of dam heightening in late stage.It also demonst rates that radial wells can lower saturate line obviously.

Abstract:Based on the analysis of influence factors on boundary angle of surface movement in coal minegoaf,this paper presents a method used to predict the boundary angle by the BP Artificial Neural Network.A prediction model of the boundary angle is constructed with BP Artificial Neural Network.Data of the boundary angle from 30 practical engineering projects are used as the assembly of training samples of Neural Network.The prediction model is then validated using data from practical engineering projects.Results from the validation show that prediction precision for the boundary angle is up to 90%,indiicating that the prediction method based based on bp artificial neural network is very useful and feasible in engineering.

Abstract:This paper introduces a case study of 6 townships in Lingyuan City,Liaoning Province.1042 surface soil samples were collect ed with the aid of GPS positioning.Traditional statistics combined with geostatistics was applied to analyze the spat ial variation of soil nutrients.Results show ed that the variation coefficients of four kinds of soil nutrients ranged from 29.45%to 67.25%.Soil nutrients,interms of the spatial heterogeneity,was in the descendant order of AP,AN,OM,and AK.AN,A K,and OM had m oderate spatial dependence.However,the C0/(C0+ C)for AP was 100%,so the relevance of space was weak.Soil nutrients,in terms of the fractal dimension,was in the descendant order of AP,AN,AK,and OM.Analysis by Krig ing method indicated that spatial pattern of soil nutrients in the study area was mainly affected by landuse type.

Abstract:The wettability of plant leaves,reflects the affinity about the water to leaves,and the water membrane on a leaf has the key influences on photosynthesis and rainfall interception.Contact angles of water were measured for 35 species plants in Shaanxi Province,and the wettability of leaves was researched primarily.Contact angles of adaxial leaves were 0%一14%,with an averaged 85.40°.According to contact angle,the plant species that are non-wettability or repellency with the value more than 95° was 31.4%of total measurements;the species with contact value less than 85° was more than 51%of the total;and there were 17.1%plant with contact angle of 85°-95°,which means that the wettability of the leaves lies between wetness and repellency.For a plant leaf,the wettability on adaxial and reverse leaves was somewhat different.The ratio of cuticle to wax of plant leaf had significance to leaf wettability.The degree of subsidiary hair on a leaf had influence to wettability and the wettability of the leaf became worse along with the subsidiary increased.If the subsidiary hair was rejected,the wettability of leaf would become better.The stoma and vein on the leaf affected the wettability through increasing the roughness of plant leaf.

Abstract:By using data from pasture observation on agro-meteorology by weather stations of Qinghai Province,the charact eristics of so il moisture in native pasture are analyzed.Soil moisture increases from west to east,with slightly high values at the two boundaries from north to south.Soil moisture in the ten-day period of each year fluctuates in a "W" type.From 1989 to 2007,it declines obviously at the rate of 0.8%/ a.In the 0-20 cm soil layer,the rate is 0.25%/ a and in the 20-50 cm soil layer,0.04%/ a.The 0-50 cm soil profile may be divided into active layer(0-20 cm),secondary active layer(20-40 cm),and stable layer(40-50 cm).Soil water content decreases with soil depth under 520 mm precipit at ion and differs in different depths when precipitation is between 350 and 410 mm.In terms of the change tendency,the change of soil moisture in Xinghai County is not obvious.It has a slightly weak drop in Chu-ma-lai County and a weak drop in Henan,Gande,and Haibei Counties.The change tendency differs from its degree in different areas.Climate change is not only the direct cause of soil moisture reduction,but also the direct cause of pasture degra-dation.Soil moisture reduction is the main cause of pasture degradation.

Abstract:Rural tourism of Chongqing City is analyzed based on space planning ideas and space design theory,by combining theory with practice.Some concepts related to rural tourism are defined firstly and then the resources,products,and subdivision of rural tourism are planed for the city.To determine the space hierarchy of rural tourism,the planning is made from micro and macroper spectives under the guidance of the planning principles of point,line,and surface on the basis of the theories of map base,association,and site.In addition,the landscape elements,landscape chains,and landscape sites for rural tourism are planned from a microper spective in order to make them link organically and prompt the orderly development of Chongqing rural tourism.

Abstract:This study aims at analyzing the complex responses between sediment movement and flood based on a series of field investigations in Hekou)Tong guan section of the Yellow River.Results show that the channel adjustments such as sediment deposition and erosion vary with the difference of storm distribution pattern./Bed-exposed erosion,sand bar,and density flow are the causes for the abnormal phenomena of floods./Bed-exposed erosion may cut down the ability of flood peak reduction;and sand bar may impound a part of flood and then be broken.As a result,they may cause flood increasing abnormally.Density flow and coalmay make floods more complex.

Abstract:After many years practice of runoff and sediment monitoring for soil and water conservation in small watershed,so me ideas abo ut the construction of monitoring station were put forward.So me problems of standardized stations/spots const ruction of soil and water conservation from the overall structure,monitoring contents,monitoring method,monitoring data management and operating management were discussed,and finally we suppose that modernized methods,facilities and monitoring data management system leastwise with the basic structure and function should be used.This can be refered by the further standardized monitoring stations/spots.

Abstract:Based on synthetic investigation and on-site survey,land resources of Ailin watershed in the northeast black soil area of China are analyzed and assessed.Landuse structure in the watershed is adjusted according to the requirements of comprehensive control of soil and water loss during ecological construction.Measures and their scales of soil and water conservation project sare defined and their benefit sare analyzed.The basis benefits and economic effects are not able and ecological and social benefit sare obvious.

Abstract:In the area lack of rain water resources,collecting rain water for ut ilization is the key to enhance the utilization efficiency of urban road rainwater.The road runoff charact eristics as water harvesting surface plays an import ant role in the collection and utilizat ion of rainwater.This art icle uses t he art ificial concrete surface to simulate road surface for the research on concrete pavement runoff charact eristics.Threshold rainfall of t he concrete pavement without antecedent rainfall is found to be 1.5 mm.Only if the rainfall amount approaches 1.5 mm,the rain water collection surface will have runoff.Road runoff coefficient increases with the increasing of rainfall amount.Runoff intensity islagging and weak in comparison with rainfall intensity.