Abstract:Wetland degradation in the Yellow River delta region occurs due to petroleum development,increasing human activities,and environmental changes. In order to understand the wetland degradation processes，sampling and survey on plant community were conducted by selecting the typical wetland plots. Meanw bile,soil features including organic matter,nutrient s,and physiological characters,as well as some soil enzyme activities were analyzed. Results showed that the plant succession was form Imperata cylindrica,to Suaeda glauca,to Tamardx chdnensds,to barren land. Consequently,soil organic matter content was decreased by 81.0%,67.4%,and 59. 5%,respectively,when form Imperatacyldndrdca was compared with the other 3 forms. For total N,the percentages were 61.1%,59. 6%,and 41.2%and for effective P,19.5%,7.9%,and 4.7%,respectively. The soil enzyme activities such as urease and invertase fell as well,while soil salinity rose during vegetation succession. It is concluded that plant community succession interacts with soil property change. Soil salinization speeds up flora succession reversely,while plant community suc-cession in adverse environment also has a certain effect on soil features. In the process,soil moisture and sa-unity movement are the key factors.

Abstract:In order to illustrate the relatively significant antierosion effects of plants covered roads,erosion processes on earth and plants covered roads under artificial rainfall were simulated indoor and in the fields. The results showed that the processes of erosion on the earth andplants covered roads were different.Plants covered road can effectively reduce the sediment and water loess,the intension of ero sion presented descrease trend,and the variations of road erosion modulus with rainfall intensity and slope gradient can be described with exponential equations;the pocess of earth covered road presented non-stability status;there is obvious effect of runoffinceasing and erosion-descreasing for plants covered road.

Abstract:Through studying the experimental results on reinforcing soft foundation by vacuum preloading on an airdrome runway in Shanghai City,surface settlement and its calculation method,dissipation of excessive pore water pressure,and reinforcing effects on test zone are discussed. The testing data indicate that the setdement in test zone,from large to small,is observed in center,margin,and corner of site and this reflects the effects of vacuumpreloading method.When vacuum degree changes,the distribution of suction pressure with depth in drained body of test zone is almost equal.The range of suction pressure is 58-65 kPa,i.e.,68%-76%of vacuum degree under seal membrane. Furthermore,the analysis show that the estimation of surface settlement of soft foundation may be carried out through combining vertical equivalent penetration co-efficient,Terzaaghi's one dimensional-consolidation theory,and layerwise summation method.

Abstract:Three typical agricultural planting areas in riparian plain of Jiangyin City,i.e.，greenhouse vineintensive planting base，vegetable intensive planting base,and general planting farmland,were selected as research objects and dynamic changes of soil nitrate nitrogen content under different planting patterns were studied by the experimental method of field sampling analysis. Results indicated that the variation of nitrate nitrogen content in vine planting base fluctuated greatly with time. However,the variation amplitude of nitrate nitrogen content in surface soil was greater than that in deep soil layer in vegetable intensive planting base and general planting farmland. Nitrate nitrogen content in three typical planting areas showed a decreased tendency with the depth of soil profile,including the maximum of soil nitrate nitrogen content appearing in the 20-40 cm layer in vine planting base. The average accumulation of nitrate nitrogen in every soil layer in vine planting base was higher than that in vegetable intensive planting base and general planting farmland. The average accumulation of nitrate nitrogen in the 0-100 cm soil layer in greenhouse vine intensive planting base was up to 400.96 kg/ hm²,which was significantly higher than that in vegetable intensive planting base and general planting farmland. This indicated that unreasonable excessive fertilization let to nitrate nitrogen accumulation in the soil profile and increased the risk of nitrogen leaching loss and groundwater environmental pollution.

Abstract:The concave surfacecharacteristics of sandbag sand barrier of different sizes in different positions of sand dune were studied in this paper. The experimental area is near Jilantai town in the southwest of Ulan Buh Desert.The sand barrier was set in April,2007 and the investigation of the concave surface was finished in April,2008. Results show that the sand barrier size and the setting position have strong influences on the concave surface characteristics.Compared with the 3 sizes,the sandbag sand barrier of 1 m × 1 m size is berreficial to the stable concave surface formulation. Compared with the 3 positions of the sand dune, concave surface on the top of dune is more stable. All the profile curves of N-S and W-E directions in different types conform to the one variable quadratic function, basically. The N-S profile is steeper than the W-E profile. It means that wind strength and wind direction can strongly influence the concave surface characteristics. The erosiorrdeposition coefficient of sandbag sand barrier stable concave surface is about 1/10. The plant in the sand barrier alsocan influence the concave surface characteristics.

Abstract:By using the method of heat pulse stem flow technique, a long and continuous observation on the Qinghai spruce stem sap flow was made in 2008. Qinghai spruce is the major local tree species, located in the high and cold loess of Datong Country's Qinghai spruce pure land, Qinghai Province. At the same time, the meteorological factors of radiation, temperature, relative humidity, rainfall amount, and wind speed are recorded by the automatic meteorological stations. Results show that the stem flow rate is of great difference because of their different trunk diameters. The change of the sample tree's stem flow rate of 20 cm trunk diameter is obviously greater than that of 10 cm trunk diameter.T he stem flow rate of 20 cm trunk diameter is of little difference month by month,but the stem flow rate of 10 cm trunk diameter is very different. Thechanges in M ay and August are greater, but in June, the changes are less.It's illustrated that when the trunk diameter has a smaller size,it is effected very severely by environment. But when the trunk diameter is greater,it has a strong ability of autoregulation and environmental adaptation. The rainfall amount is 409. 1 mm in the four months,on the verge of the whole year rainfall. Total transpiration quantity is 386.45 mm.It lakes of water about 38.71 mm in May. The amounts of surplus rainfall are 74. 68,20.92 and 45.76 mm in June，July,and August,respectively.

Abstract:Soil fertility and mineral N accumulation of slope apple orchard on the Loess Plateau are studied.Results show that soil appears low-fertility due to the serious lack of N and P. Soil is sandy loam，with better soil aeration and poor water and nutrient retention. Fertility status of slope apple orchard on the Loess Plat-eau is low on the whole. The content of soil nutrients of the 0-60 cm soil layer is as follows:organic matter is 9.24-28. 12 g/ kg;total N is 0. 22-0. 60 g/ kg;available P is 0. 17-16. 08 mg/ kg;and available K is 80.06-168.39 mg/ kg. There are NO₃- -N enrichment layers below 2 m of slope apple orchard on the Loess Plateau.Different fertilizations have significant effects on the NO₃^- -N distribution and its content in the soil profiles，while the NH₄⁺ -N distribution and its content were relatively constant.For more N treatment，the NO₃^- -N enrichment depth increases，while for more P treatment，the NO₃^- -N enrichment depth decreases in the soil profiles.

Abstract:Head cut is a widespread and serious erosion type on the Loess Plateau and it has already threatened farmlands，local residents,roads，and factories. According to the field investigation on Dongzhiyuan,the influence factors of head cuts are natural and human factors. The natural factors mainly include runoff，topo grap by，and soil.The genetic types of head cut are summed up，including flow-induced type，sink hole-induced type，fissure-induced type，and human-induced type. According to the order of time,the development of head cut can be divided into three stages:water erosion stage，water and gravity erosion stage,and gravity erosion stage. The control measures of gully head are presented based on the characteristics of different erosion types.

Abstract:Field survey and laboratory observation experiment were conducted to study the character of soil seed bank for Pinus Tabulaef ormis Plantation in wuling Mountains，such as species composition，density，and the vertical distribution of species. Results indicated that(1) the average seed storage of seed banks was 5 711 grains/ m² and the minimum and the maximum storage were 3 563 grains/ m² and 9 537 grains/ m²,respectively. (2) Vertical distribution of the soil seed bank mainly concentrated in the three levels of 0-2.5,2.5-5,and 5-7.5 cm,accounting for 75.38%-79. 32%,and for the forest flooring and the 7.5-10 cm level,the distribution accountedfor 20.68%-24.62%.(3) Species composition of the soil seed bank for the two types of shrubs and herbaceous,non tree plant,the perennial herb occupies the obvious superiority in the species number and the seed number.

Abstract:To test the drought resistance of eight provenances(PRs) of Chinese pine(Panus tabulaef ormas Carr.),a soil water treatment experiment with water gradients(T₁:w ater content was 25%-29%,T₂:19%-22 %,and T₃:12%-15%)for 120 potted 3-year-old seedlings was conducted. Some physiological and biochemical indexes such as net photosynthetic rate(Pn),transpiration rate(Tr),superoxide dismutase (SOD),activity,and peroxidase(POD) activity were measured and analyzed. Results showed that no significant difference was observed in Pn，among the provenances ander T₃>0.05). How ever,PRz had significantly higher Tr than PR₁，PR₃,and PR₅ and PRs₅ had significantly higher water use efficiency(WUE) than PR₂,PR₃，PR₄, PR₆，PR₇, and PR₈(P<0.05) under T₂.In comparison with those under T₂,the SOD activity of all provenances and the POD activity of most provenances reached a higher level under T₃.PR₇ and PR₈ had weaker membrane lipid peroxidation and PR1,PR₃, PR₄,and PR₅ had stronger membrane lipid perm oxidation. In terms of the drought resistance of the provenances, the treatments had the following order of PR₈> PR₆> PR₁>PR₅> PR ₄>PR₃≅PR₇>PR₂.

Abstract:Taking a sloping field of purple soil in the Three Gorges Reservoir area as an example，the authors synthetically evaluate purple soil degradation using Fuzzy model based on different landuse types and different slope segments and analyze the main driving forces leading to the degradation. Results show that vegetable land and garden are not subject to degradation;cultivated land and woodland have light degradation;grassland and wasteland have moderate degradation;construction area have severe degradation;and all the sloping fields of purple soil in different slope segments have moderate degradation. Human activities are the main factor of soil degradation in the Three Gorges Reservoir area and soil erosion is the main type of soil degradation. Natural factors such as landform,climate，parent rocks，purple soil characteristics are the conditions to soil erosion. Human factors such as severe vegetation destruction,a great many of sloping fields，and high reclamation rate，improper cultivation measure,and irrational planting system accelerate the soil deeradation in the area.

Abstract:Muddy water with high concentration often occurs in rainstorms on the Loess Plateau,which directly influences runoff and sediment yield on slope. Know ledge of muddy water infiltration with different concentrations is important to the study of soil erosion on slope. By taking clean water as control, infiltration characteristics,infiltration processes,and infiltration decay ratio of muddy water with different concentrations were measured. Results showed that the infiltration rate at the end of first second, the stable infiltration rate,and the cumulative infiltration amount decreased exponentially with mud concentration, while the infiltration decay ratio increased logarithmically with mud concentration. The two relationships appeared steady as mud concentration increased. In the same time interval,the cumulative infiltration amount of clean water was always the highest,but decreased as mud concentration increased. Muddy water had a decreasing effect on infiltration.

Abstract:By the methods of field survey and incubation experimentations，soil microbial counts and enzyme activities on three typical railway cutting slopes located in Jiajiang section,Wufeng section，and Baiyun section of Sichuan Province were investigated. Results showed that the soil microbial counts on railway cutting slopes displayed obvious seasonal fluctuation. The quantities reached their maxima in summer on the three slopes and followed by those in spring and autumn，while the quantities reached theirminima in winter. The detailed maxima of bacteria，fungi,the average soil microbial quantity per year on the investigated railway slopes were all higher than those on natural slopes selected as controls. In addition，soil enzyme activities also presented apparent seasonal fluctuation. To be specific，the activities of all the enzymes reached their maxima in summer and autumn，as contrasted with their minima in winter. The average enzyme activities per year of the urease and the catalase on the railway slopes were all higher than those of the controls,however,the indicator of the saccharase on the railway slopes was lower than that of the controls. Seasonal fluctuadons of soil microbial quantity and enzyme activities on railway slopes were similar to that of natural slopes.Some correlations were found，including very significant correlation(r=0.999) between the bacteria and the algae inJiajiang section;significant correlation(r=0.969) between the fungi and the catalase inJiajiang secdon;significant correlation(r=0.978) between the urease and the saccharase in Wufeng section;significant correlation(r=0.963) between the bacteria and the urease in Baiyun section;and significant correlation(r=0.962) between the algea and the urease in Baiyun section. However，the correlation among all other factors on railway slopes was not significant.Temperature was the major influencing factor of soil microbial counts and enzyme. Soil microbes growth and function of micro-organism produce enzyme were disturbed by human activities.

Abstract:Soil erosion on the Loess Plateau is serious due to precipitation,temperature,and other natural climate constraints and thus,determination of an appropriate stand density becomes very important. In this study,we conduct a systematic research on several aspects of the existing plantation in Caijiachuan,such as stand growth status,water storage capacity of forest litter, biodiversity,and physical properties of soils. Results show that,in order to improve the growth conditions,biodiversity,and soil physical properties,the best planting density of black locust,Panus,and the mixed forest should be 1 325,1 733,and 2 089 plant/hm²,respectively,whereas by considering the water storage capacity of the forest litter,the result turns out to be 2 133,2 222,and 2356 plant/hm²,respectively.Besides,the mixed forest has the highest biodiversity index and evenness index and the nor-capillary porosity and the capacity of the water conservation of forest soil in locust forest are also the host.

Abstract:A field experiment was carried out to study the effects of the application of a new soil conditioner to grain yield，water use efficiency (WUE),and phosphorus fertilizer use efficiency(PUE) of winter wheat.Results showed that the application of the new soil conditioner could improve grain yield,WUE,and PUE. When the new soil conditioner was used at 1 500 kg/ hm² in a wheat field，grain yield and WUE were increased by 15% and 21.65%,respectively. PUE was 2.92% higher than that under single application of phosphorus(P) fertilizer. Grain yield by applying the new soil conditioner with irrigating water at 33.3 mm level was 28.57%more than that under control and mixing with P fertilizer could increase grain yield by 42.86%.PUE was 11.11% higher than that by single application of P fertilize and WUE was up to 25.06 kg/ (hm²·mm).

Abstract:By the laboratory experiments,the effects of konjac super absorbent polymer (KSAP) on water preservation in soil were studied using factorial designed experiment. Results showed that the effects of soil water preservation were significant(P<0.01) when different additions,different dosages and particle diamenters ters of KSAP were added to the soil,whereas the frequency of irrigation on water preservation of KASP was not significant. The effectivewater in sand,red soil,and brown soi1 were increased by 32.7%,18.1%and 24.3%,respectively,when KSAP(0.30%,particle diameter 0.80mm) was sprayed to surface.

Abstract:The study was designedfor the purposes of controlling grassland degradation,protecting biological re sources,and keeping a benign cycle of ecology,society,and economy. With restoration ecology as a guide,a soil evaporation experiment was conducted to analyze the effects of different material covers on soil moisture in the typical steppe zone. Results show that gravel and hay covers can effectively inhibit soil evaporation. The inhibitory effect of hay covers is more significant than gravel in the whole evaporation process.

Abstract:Determination of soil texture is affected by various factors and ought to adopt a method of comprehensive fuzzy evaluation. Based on Kaczynski soil classification standard and ridge-type subordinate function,texture type of 4 Holocene loess profiles with 30 layers in the Guanzhong region was determined by applying synthetically decided method of weighting average. Results indicated that texture types of Malan loess (L₁)，illuvial horizon (Ck)，and Holocene loess (L₀) are identical and thus，do not have the significance of instruction. However,Holocene paleo sol (S₀)，airslake andleaching loess (C₁)，and modern topsoil(Ts) are difEerent.From east to west,soil texture types of So and G change from heavy loam soil,medium textured soil,to light textured soil. The change of topsoil(Ts) is indeterminacy because it is obviously affected by the human activities.

Abstract:Gras exchange parameters of three new poplar clones (JK-7，JK-10，and JK-11) and the correspond ing environmental factors were measured in order to explore the relationships of net photosynthetic rate (Pn),Transpiration rate(Tr),water use efficiency(WUE)，and the environmental factors such as photosyn-thetically active radiation (PAR)，air temperature(Ta)，vapor pressure deficit (VPD)，and relative humidity (RH}.Results showed that the three clones were different in response to the same environmental factors.The diurnal courses of P and T,displayed single peak curves in JK-7 and JK-11 and a double peak curve,in JK-10,while the diurnal courses of WUE displayed double-peak curves in all clones. There were significant differences in P and T,among these clones(P<0.05),with the highest in JK-10 and lowest in JK-7,and they were significantly higher in JK-10 than in JK-7.There was no significant difference in WUE among these clones. The Pn and Tr,had close correlations with stomatal conductance(Gk)and PAR in the three clone s,while they had close correlations with RH in JK-7 and Tuain JK-10. There was significant negative correlation between WUE and Gk in the clones.

Abstract:As the main tree species of farmland shelterbelts in North China，the transpiration rates of Pinus sylvestris L.var. mongolica Litv.,Larix gmelinii，Populus sdmondd XP. ndgra,and Populus alba XP. berolinensis were studied comparatively by the method of rapid weighting. Results showed that(1) the diurnal variation of transpiration rate of Pinus sylvestris L.var. mongolicaLitv. mixed with Populussimonii XP. ndgra and Pdnus sylvestrds L.var. mongoldca Litv. was of little difference，monthly variation of transpiration rate for them was the slowest，and the transpiration rates of other structures showed a parabolic trend.(2) Monthly averaged transpiration rate of Lardx gmelinii mixed with Populus sdmondd XP. ndgra accounted for 76. 96%of Larix gmelinii and the averaged transpiration rate of Populus simonii XP. nigra mixed with Larrix gmeldndd was 17.43%lower than that of Populussimonii XP. nigra. The structure mixed with Populus simonii XP. nigra and Populus simonii XP. nigra could decrease the transpiration rate of the two tree species. (3) The transpiration rate of farmland protection forest was seriously affected by atmospheric temperature and solar radiation in a variety of environmental factors in combination. The transpiration rate showed the positive correlation with atmospheric temperature，solar radiation，and soil water content，but negative correlation with relative humidity and wind speed.

Abstract:Study of soil moisture content and its dynamics on road slope is important to choose appropriate plant species for bio-engineering re-vegetation and improve slope stability. Soil moisture content and its dynamics on road embankment and cutting desert expressway. Results showed that soil moisture content on embankment and cutting slope had the typical seasonal dynamics.Soil moisture was higher during May and June,while it was lower during July and September and resumed gradually during October and December. Vertical distribution pattern ture content was the lowest in surface soil layer. Soil moisture content increased with increased soil depth and it was higher on road embankment than cutting slope.

Abstract:Ecological processes and ecological phenomena have their particularities in extreme arid zone. By analyzing the mode and method of expression of ecological information,its meanings andfeatures，as well as its relationships can be easily understood. By using remote sensing images including LANDSAT/ TM in the beginning of 1990s and 2000,as well as CB ERS-2/ CCD in 2005,the 4 first level types and 13 second level types of landscape type in Turpan，an extreme arid zone of China，are classified based on coupling relations in Mountainous Oasis Desert System(MODS).Meanwhile,the thematic symbol system of ecological landscape is designed by using the GIS symbol base and considering the objectivity andpracticability. The ecological information TUPU is constituted of graph and special symbols,descriptive digital parameters，and mathematic models. Under the support of ERDAS 8.5 and ArcGIS 9.0,a landscape ecology map is made.

Abstract:Linear decomposition time series analysis has become one of useful tools to investigate runoff characteristics, but how the sequence length affects the results of linear decomposition has not yet been studied in detail. In this paper,the runoff time series at Zhuqi station of the Minjiang River and the inflow time series at Baishan reservoir of Songhuajiang River are selected to investigate the effects of time series length on rurr o ff characteristics. Six sequence lengths are selected according to the available runoff time series over 70 years, and the linear decomposition for different length is conducted. Results show that the characteristics of runoff,such as shift trend,jump change, and periods have been affected obviously by sequence length. It is suggested that the reasonable sequence length necessary to conduct linear decomposition and reasonable sequence length may be correlated with the time scale of time series.

Abstract:By taking the Northern Shaanxi Loess Plateau as a study area,the topographic wetness index is calculated by using the single flow direction algorithm and multiple flow direction algorithm. In calculation，it is considered that the flow direction algorithm will have a significant impact on the result of topographic wetness index. The correlation of soil moisture and the topographic wetness index are analyzed based on the data which consist of sampled soil moisture data and topographic wetness index data. The quality of topo-graphic wetness index data calculated by using the single flow direction algorithm and multiple flow direction algorithm are then compared. The best flow direction algorithm to soil moisture simulation is put forward.

Abstract:SWA T model is one of the most active non point source pollution models. Combined with GIS，it can simulate non-point source pollution under the different conditions of land use in complex large river basin. This study is based on the basic database of non-point source pollution and the integrity of the measured data and uses the GIS integration with the SWAT 2000 model.Model parameters are estimated using the measured data of water,sediment,and nutrient load from 1991 to 1996 and are verified using measured data from 1997 to 1998.Applicability and reliability of SWAT model in non point source pollution simulation in Heihe River basin are determined，which provides a reliable model foundation for non-point source pollution simulation in Heihe River basin of Shaanxi Province.

Abstract:The Management Information System if Rural Land Circulation(RLCIS) is useful to automation administration,intelligent inquire,statistics analysis，and I the policy decision to some subjects. Based on the workflow modeling of RLCIS,the purpose and process of system design are defined and the overall frame work of RLCIS is then designed. The development process of RLCIS and its main functions are presented.Lastly,the RLCIS of county land department is designed.

Abstract:By taking the loess in Mangling District,Shaanxi Province as a research object,a direct shear creep test is conducted to obtain the char acteristic creep curve and parameters of intact loess under different water contents and analyze the influences of water content and shear stress on creep characteristics. Results indicate that at a given water content,shear stress obviously influences the creep characteristics. The higher shear stress, the greater creep strain of loess. At a given shear stress, water content obviously influences the creep charactristics. The higher water content,the bigger creep strain. According to the typical behavior of creep curve,a creep constitutive model and characteristic parameters are obtained by fitting test data. The model better simulates the creep characteristics of intact loess in Mangling District by model test.

Abstract:The establishment of soil information system is of great importance to soil information sharing and utilization. By taking Shaanxi Province for an example and using Geodatabase model and Access, the spatial and attribute databases were established respectively. Based on the ArcEngine 9.2 component and combined with ADO. NET technique,soil information system of Shaanxi Province was developed in VS 2005.NET environment. The system has several function models such as layer management,data management,output,spatial analysis,and evaluation models. The establishment of the soil information system is of great significance for soil informatization and decision2making of Shaanxi Province.

Abstract:Shear failure of compacted loess in different frequencies is studied using a torsion shear apparatus and the effects of frequency on dynamic strength and dynamic strength parameter are investigated.(1) At a certain defined confining pressure, dynamic strength of compacted loess increased with the rise of the frequency, showing a poses tive relation with frequency.(2) At a certain defined frequency,dynamic strength of compacted loess increased with the rise of confining pressure.(3) Both dynamic cohesion and internal fraction angle of compacted loess are increased with the rise of frequency.(4) The dynamic cohesion and the internal fraction angle are decreased and tend to be steadv with the increased vibration.

Abstract:The effects of stubble application and slope gradient on soil and water loss are studied. The 15 cm stubble mulch application can reduce runoff amount by 18.6>.Stubble application can reduce sediment yield by 14.36>-19.47>.Crop stubble application with a height of 5,10，and 15 cm and slope gradient has no significant effects on initial runoff time. The 150 slope steepness has a significant effect on soil erosion. The 15 cm stubble mulch application has the most significant effect on soil and water conservation.

Abstract:Reasonable determination of index weight is of great importance to get an objective and reasonable evaluation result of water saving and improvement evaluation in irrigation district.In order to obtain the objective and reasonable index weight,two kinds of combination weighting method with different principles are applied to index weight calculation and the calculated result are applied to benefit evaluation of water saving and improvement in irrigation district.It is found that the two kinds of index weight vector sequences are the same. The sequences of the two kinds of evaluation result for four irrigation districts based on the two kinds of weight are the same though the evaluation values are different.Finally,the causes of the result and the application condition of the two kinds of combination weighting method are analyzed.

Abstract:Based on the correlation data of grain production in Mizhi County from 1990 to 2007，the grey correlation analysis is made to analyze grain production with the variation characteristics of the cultivated land，population，and other influencing factors. Results show that the program for the conversion from cropland to forest and grassland is the main reason for the cultivated land decrease. Improvement of unit yield and total grain production is the key factor to protect grain security. Population growth has a great influence on the bearing capacity of cultivated land and put forward a greater challenge to grain security in the area. To increase the grain yield,some suggestions are put forward,such as increasing science and technology input to enhance unit yield,protecting cultivated land,and excavating the potential of cultivated land. The study provides a scientific basis for government policy making.

Abstract:The Danjiangkou Reservoir is the water source area of the MiddleRoute of the South-to-North Water Transfer Project.Wetland vegetation in the Danjiangkou Reservoir region is essential for the water transfer project.Vegetation survey indicates that there are abundant aquatic plant species and various plant communities in the reservoir wetlands. However,almost all kinds of current wetland vegetation in the reservoir shorelines will be permanently inundated and new wetland vegetation will develop at higher elevation after Danjiangkou Dam heightened. According to canonical correspondence analysis(CCA) and stepwise regression analysis based on the relationships between vegetation and environmental factors，we predict that new wetland vegetation will be dominated by Cynodon dactylon and mesophyte characterized by low species diversity in the areas of large slope,and Paspalum paspaloddes and hygrophyte are dominant species in the flat areas with relatively high species diversity.

Abstract:Based on the principle of ecological footprint,the ecological footprint and ecological safety of Xianyang City from 1999 to 2006 were quantitatively analyzed. Results showed that the ecological footprint per capita gradually increased year by year,the ecological capacity per capita gradually decreased,the ecolo gical deficit per capita and ecological tension continuously increased,and the social economic development was not coordinated with ecological environment,which indicate that the development of the city is not sustainable and its ecological environment is not safe. Though the ecological footprint of 10 thousands Yuan GDP had a dropping tendency,it was still greater than the averaged national level in 1999，which shows that the resource use of the city was still an resource exhausting and extensive management pattern. Finally,by considBring these facts,some available ways for the sustainable development of Xianyang City were brought up.

Abstract:The Returning Farmland to Forest Project the biggest ecological engineering in China, which brings up great economic and social performance to the afforested area. This paper analyzes the socioeconomic performance of Zhi idan County and Zizhou county in Northern Shaanxi Province before and after returning the farm land to forest,and studies the impacts of the project on grain output, agriculture output value,forestry output value,grassland farming output value and constituent ratio,and per capita income. At the same time,it analyzes the social performance from labor force transferring and peasant consumption expenditure,compares the above changes in the two counties，and provides suggestions on how to maintain the achievementis of the project and regional evelopment in the two counties,and assures healthy development of the project.

Abstract:Ecological Footprint is a significant account for overall assessment of the status of sustainable development and a comprehensive indicator for human recourse consumption. Calculation of the local ecological footprint of Ningbo City in 2002 and 2005 shows that the average local ecological footprint is 3.155 3 hm² and 4. 344 0 hm²,ecological capacity is only 0. 351 4 hm² and 0. 364 9 hm²,and the local ecological deficit is 2. 825 3 hm² and 3.999 2 hm².Ecological footprint intensity index of Ningbo in 2005 is 12.599. Fro m t he resups it follows that the demands of human consumption exceed the capacity of natural ecosystem and ecological environment is deteriorating at a rapid pace. In a word,the situation of sustainable development in Ningbo City is not optimistic.

Abstract:Effects of landuse change on ecosystem service value in Liling County from 1996 to 2005 were studied by using the table of China land ecosystem service values of unit area，ESV computing formula，and ESV coefficients. Results showed that the landuse change is mainly reflected by the decrease of cultivated land and waters area，as well as the increase of woodland and construction land. Although the value of ecosystem services arising from landuse change caused by the value of the coefficient differences is offset each other，the value of ecosystem services in the city is reduced 35 620 000 yuan，which deserves our great attention.

Abstract:An experiment was conducted to study the water conservation capabilities ofPinusmassoniana and Gordonia Svchuanensvs mixed forest(MDH),Gordonia Svchuanensvs and Symplocos setchuensis mixed fort est(DSH)，Pinusmassoniana and Lindera kwangtungensis mixed forest(MKZH),Lindera kwangtungensis and Cunninghamia lanceolata mixed forest(G SZH)，Pinus massoniana burned area(MJD),and lostachyspubescens mixed forest(NMH) in Jinyun Mountains,Chongqing City. Results showed that for wagter holding capacity above ground, the order of forest types was DSH(73. 871 t/ hm²)>NMH(71.136 t/hm²)>MDH(58.103t/ hm²) >MKZH(57. 43 0 t/ hm²)>GSZH(30. 677t/hm²)>MJD(19.010 t/hm²);by the actual effect of storing of litter, NMH>DSH> MKZH> GSZH>M DH>MJD; by water-holding cat parity of noncapillary porosity, NMH(204. 300 mm)>MJD(168. 909 mm)>MKZH(145.598 mm)>GSZH(137. 547mm)> MDH (48. 919 mm)>DSH(43. 096 mm);and for water conservation capacity of different forest types, NMH(211. 4 mm)> MJD(170. 8 mm)>M KZH(151. 2 mm)>G SZH(140. 6 mm)>MDH(54. 6 mm)>DSH(50. 2 mm).

Abstract:Based on the data from landuse change survey in Anhui Province from 1996 to 2005，the evolution of landuse pattern in the province is studied using structural quantitative analysis methods of landscape ecology. It is found that the diversity and evenness of landuse show an upward trend and the dominance shows a downward trend. The drive mechanisms of the evolution of landuse pattern are studied by means of canonical correlation analysis of NOSA and the trend of evolution of landuse pattern is predicted using GKSIM model.Results show that by 2020,the areas of cultivated land，garden land，grass land,water surface,and unutilized land will decrease,but forest land，ho using,industrial and mineral land,as well as land for traffic will increase;and the rate of landuse change will decrease. The study is significant for the optimization of land resource allocation and the rational use of land resources and gives references for landuse plan and landuse policy making.

Abstract:It is important and necessary to make further studies on comprehensive fertility estimation in urban forest soil which plays an important role in the sustainable development of urban forest and ecosystem. In this paper，modified Nemoro Index(Q) was used to assess the fertility quality of urban forest soil with the 6 indicators of soil bulk density,texture,pH,organic matter,available potassium，and cellulase activities in Nanjing City. Results showed that the range of Q of urban forest soil was 0. 85-1.51,the mean value was 1 .19±0.17,and the percentage of soil samples in the middle level of 1.0≤Q<1.5 was 90. 91>.Soil fertility Q in suburban forest and mixed forest of tree，shrub,and grass were comparatively high，while that in road green belt and lawn was just the opposite. It is concluded that the fertility of urban forest soil in Nanjing City is in middle-low level and needs to be restored immediately,and the lawn is not the ideal material for soil fertility restoration.

Abstract:Based on in situ investigation，observation，and test,green plant,slope soil physical and chemical properties,and plant community composition on the Huangling --Yan'an Highway are studied. Through analyses,plant species in the central reserve,platform and slope,and the advanced allocation model are summarized and the reasons of soil nutrient pool and improving measures are analyzed. Accordingly，several relevant conclusions are made. Soil fertility and plant restoration is complement and soil fertility is gradually restored with time after artificial vegetation construction. The number and proportion of species have a great change with the passage of time,which is beneficial to plant community of slope to reach structural stability.

Abstract:The theory of energy analysis was applied to select a typical representative village Dazuizi Village located in the desert oasis borderland as a research object.The composition of energy inputted and outputted，energy indices were calculated. Net energy yield ratio was 3.1;energy investment ratio,17.38;environmental loading ratio，0.82;energy sustainable index，3.77;and selfsystem feedback ratio,0.39. Compared withJiangsu，Harman，and Cransu Province,results showed that the system which is irrigatedfrom the Yellow River achievedfavorable ecological and economic benefits and strengthened the potentiality of sustainable develop ment.Production feature was a lot of energy inputted and the combination between planting and livestock breeding.The production mode was typical in arid area,but some problems were still existed. Accordingly,countermeasures and suggestions were presented.

Abstract:By taking Baiji City of Shaanxi Province as a research object,land sensibility and its spatial distribution are studied in views of the sensitivities to soil erosion，bio-diversity protection,and geology disaster under support of GIS technologies.Single and comprehensive element sensitivity assessment is used in the study. Results show that regional differences of land eco-environmental sensitivity in the city are comparatively obvious. The proportion of slightly sensitive area to the total area is 62.1>;the moderately sensitive area acco unt s for 37>;and highly sensitive area shares the smallest proportion,only accounting for 0. 9>.By combining with the result of ecoenvironmental sensitivity assessment,countermeasures for ecoenvironmental construction and protection of each of the areas are proposed and a basis for government making land policy is provided.

Abstract:By taking the Yuzhong area as an example,thematic raster layers of each evaluation factor are established based on DEM,survey data, remote sensing images,and 3S technologies.From the humanistic and natural point of view,vigor,organization,load,resilience,ecosystems maintenance,external input,and human health are chosen as the assessing elements based on the method of AHP.T he assessing result is classified into five classes: very healthy state,healthy state,sub healthy state,nor-healthy state,and morbidity state. In the end, the following conclusion is drawn: the area of nor-healthy state makes up 40>-50> of Yuzhong County,which indicates that the ecosystem healthy state declined from 1991 to 2006.

Abstract:Combined with the method of Analytic Hierarchy Process,a reusable pressure Mate response (PRS) model is set up to evaluate the sustainable land utilization for the Enping City in the Pearl River region. The transformation process and mechanism of land quality are analyzed and the man wand relationship of sustainable land utilization is revealed. The coordination degree of pressure,state,response,and the comprehensive coordination degree of Enping are calculated. The study shows that the PSR model can be applied in practice and it should be used in the area which has all kinds of data. The strategies of population growth co ntrolling,intensive and save land utilization,land consolidation and reclamation,and appropriate urbanization process should be taken in order to achieve the sustainable land use for Enping City.

Abstract:A super absorbent resin based on acrylic acid has been successfully prepared by Ultraviolet Photo-initiated(UV) using polyvinyl alcohol as a crosslinlcing agent.The magnicide absorption amount of the resin for distilled water reached 4 100 g/ g and for sodium chloride solution in concentration of 0.9%，reached 405 g/g. The polymer was characterized by FTIR and TG. The effects of the quantity of water,time,pH,temperat ure,and fertilizer on the liquid absorbency of polyacrylate sodium in sandy soil and solution were then studied by indoor simulation experiment and the effects of polyacrylate sodium on the resistance water and germinating capacity were also investigated. Results showed that(1) the liquid absorbency rate in sandy soil was less than that in solution and the time of absorption saturation was longer than that in solution;(2) the effects of pH (4-10)，temperature (200-700)，and the nonelectrolytes fertilizer on liquid absorbency were rather small;(3) the liquid absorbency was heavily influenced by the electrolytes fertilizer;(4) the result of potted plant experiment showed that the poly (acrylate sodium) greatly improved exaltating seedling rate and soil water holding capacity.

Abstract:The technique of whole plasticfilm mulching in corn planting with double ridges and furrows on dryland before sowing has been failed to conserve sufficient soil moisture and use the autumn rain in the next spring. Field plot experiments were conducted for three years to test the techniques in three different film mulching times:autumn，early spring,and the time before sowing. Results showed that compared with the conventional film mulching cultivation(full mulching before sowing),the autumn whole mulching of double ridges and the early spring whole mulching of double ridges increased the water content in 0-100 cm soil layer by 2.7%and 1.5%,respectively,and increased water storage in 1 m soil layer by 245-501 and 138-317 m3 / hm²,respectively. The techniques increased the average field rainfall use rate of 8.5%and 5.6%,respectively,and the corn water use efficiency of 5.54 and 2.88 kg/ (mm·hm²),respectively. The techniques of the autumn and early spring whole mulching of double ridges are technical modes of high-efficiency rainwater use of corn in the arid and semiarid agricultural areas with elevation of below 2 300 m and annual precipitation of 350-500 mm. The best covering time is before the soil is frozen in late autumn (generally from the last or the middle ten days of October and the beginning of November) and when soil is melted in daytime and is frozen at night (generally in the early-middle of March).

Abstract:By using remote sensing(RS) and geographic information system(GIS),the landlorm pattern and the change of residential area of the 8 counties belonging to Weinan City are analyzed based on the TM data in 2000 and CBERS data in 2007. Results show that land form patterns are complex and diversiform with mountain,plain,valley,sandy-land,channel,etcin which the flatland above plain and the valley in the north bank of Weihe River occupy over 20% of the total land area. T he total area of residential sites in all counties increased by 6 044.1 hm² during the 7 years, in which the biggest is 2 718.6 hm² in Linwei District,the seeond is 1 057.8 hm² in Dali County,and the least change is 123. 1 hm² in Tongguan County.T he d ynam is degree of overall region studied is 2.03%,in which the most one is 3.75%in Linwei District and the least one is 0.85% in Chengcheng County.

Abstract:Quantitatively study on land use change and ecosystem service value in fast developing areas will be a scientific basis for reasonable pricing,effective compensation of ecological resources,and coordinated development of natural ecosystem and socioeconomic system. Analysis of the changes of land use in Guangzhou City adopeted the single land use dynamic degree model,land use degree comprehensive index,and land use degree change rate. The coefficient of ecosystem service value proposed by Costanza and Xie Gaodi was used to Quantitatively study on land use ecosystem service value and its influence mechanism in Guangzhou City. The relationship between ecosystem service value and its major factors of social economy was explored by correlation analysis and sensitivity analysis. The results showed that total value of ecosystem service of land use in Guangzhou City decreases year by year，and ecosystem service values of forestland,water and garden land account for a higher percentage. The changes of land use structure and the area of different types of land cause a fluctuation in ecological service value. There is a negative correlation between ecosystem service value and population,GDP and urbanization degree，which indicates that the economy development is the cost of the loss of ecosystem service value. The change of ecosystem service value lacks elasticity with population,P and urbanization degree，comparatively speaking,it is sensitive with the population changes,then is urbanization degree，and with no sensitive with GDP.

Abstract:According to vegetation succession stage and plant growth form in the ecological restoration process in the hilly-gullied Loess Plateau,erosion-resistant species may be divided into annual herb plant,perennial rhizome grass plant,perennial rootshoot herb and subshrub plant，shrub plant,and arbor plant.The changes of the erosion-resistant species in the ecological restoration process show that annual herb plant and perennial rhizome grass plant have higher ability to adapt soil erosion environment and a certain extent of effect to prevent soil erosion，while shrub plant and arbor plant have weaker ability to adapt soil erosion environment but very strong effect to prevent soil erosion. The ability of perennial root-shoot herb and subshrub plant to adapt soil erosion environment is in the middle，with their ability to prevent soil erosion is superior to annual herb and perennial rhizome grass plant,but inferior to shrub and arbor plant.The recommendadons on the practice of afforestation based on the restoration of natural herb vegetation are put forwarded.