Abstract:In order to study effects of different tillage methods on soil and water conservation(SWC) and soil carbon stock in red-soil slope land in Southern China,field experiments were carried out in the representative area named Jiangxi Eco-science Park of SWC to investigate the surface runoff,sediment,total organic carbon(TOC) and carbon pool index(CPI) of soils in contour strip intercropping,downslope strip intercropping and clean tillage in orchards with the data of five-year agriculture measurement.The results indicated as follows:(1) Compared with the control(CK),runoff reduction rates of the three measures varied between 21.16% and 75.32%,and sediment reduction rates of them varied between 38.08% and 80.57%.It showed that these agricultural measures have great effects on reduction of runoff and sediment with a descendant order of contour strip intercropping,downslope strip intercropping and clean tillage.(2) Compared with CK,soil TOCs and CPIs of contour strip intercropping,downslope strip intercropping and clean tillage increased by 37.24% to 6.34% and 35.23% to 55.34%,respectively.The results also showed that these agriculture tillage measures have increased soil C and followed a descendant order of downslope strip intercropping,contour strip intercropping and clean tillage.(3) These results indicated that strip intercropping has better benefits than clean tillage and can be applied widely in red-soil hilly region.

Abstract:The paper focused on soil infiltration rate and soil moisture content under 12 different land uses in semiarid region of loess.The results showed that soil moisture content was about twice under the same land uses in the farmland-sloping,which was significant difference.The gap was about 35.23% in the drought terrace,5.84% in the hillsides,no obvious difference was found in the ditch platform.Artificial vegetation played an obvious role in improving soil moisture content.When infiltration continued 180 minutes,contrast to unculivated land the soil moisture content of Poplar plantation,enclosed grassland,Caragana plantation,Seabuckthorn plantation,Plnus plantation,mixed plantation was 108.19%,173.43%,157.76%,192.28%,93.64%,129.67% respectively.Soil moisture content in the artificial shrub lands,such as seabuckthorn forests,caragana lin,was larger than artificial arboreal lands.The way of plough in hillsides was an effective measure in soil and water conservation.Soil bulk density acted as an active index affected soil moisture content,which soil bulk density was bigger,soil moisture content was smaller.Soil infiltration rate was 9.60%~19.02%,which would not affect soil moisture content.

Abstract:Grain size characteristics of aeolian sediments can provide lots of information about sedimentary environment and process,sediment transporting forces.This paper selected the semi-fixed and fixed dunes at Minqin County as research objects,and studied the sediment samples systematically using the grain size analysis method.The results indicated that fine sand is dominant in the semi-fixed and fixed dunes surface sediments,and the very fine sand follows;the grain size compositions of semi-fixed and fixed dunes are similar,but difference in contents of components can be detected.The mean diameters of semi-fixed and fixed dunes are 2.69 Φ and 2.66 Φ respectively with similar sorting and skewness features,showing nearly symmetrical distribution patterns when moderately sorted.The analysis of the grain size parameters showed that a quadratic polynomial relationship(R²=0.404 1) exists between the mean diameter and skewness,but insignificant linear correlation can be found among kurtosis and the mean diameter,the sorting feature,kewness show(0.550,0.496,0.356),and the sorting feature and the mean diameter,skewness are uncorrelated.

Abstract:Sedimentary transport of Xiaojiang River was analyzed by a case study of debris flow in Jiangjia gully on August 4,2009.The entrance of debris flow into the river greatly changed the characteristics of suspended sediment transport,in comparison with the observation data during the rainy season.The sediment concentration increased from 4.00 kg/m³ to 25.78 kg/m³ after the confluence of debris flow,yet the grain composition remained almost the same.Furthermore,granular analysis was conducted on the slurry of debris flow and the suspended sediment at the Xiaojiang bridge and Xintian dam,the results showed that the suspended sediment at Xintian Dam mostly came from the debris flow,resulting in the smaller average grain-size parameters(the maximum value decreased from 7.460 μm to 7.097 μm),but the sorting of them had been enhanced and fell into the medium-sorting.Simultaneously,we noticed that there was still a clear distinction between the sediment slurry of water and debris flow.

Abstract:Different typical water samples were collected from July 22 to July 28 in 2005 in Lijiang Basin of the Hengduan Mountainous Region for chemical characteristics study.Principal component analysis(PCA) and correlation analysis were used for data analysis,the results showed that the dominant cations were Ca²⁺ and Mg²⁺,whereas SO₄^-2 were major anions.The analytical results suggested that the orders of water concentration,from high to low,were the glacial lake water,melt water runoff,lake water,surface runoff and groundwater.PCA results showed the lithological characters definitively influenced the ion content of water in the Lijiang basin,which also were effected by human activities.Correlation analysis showed that the concentration of Na⁺,K⁺,Mg²⁺,Ca²⁺ highly correlated with the lithology,whereas Cl^-,and NO^-3 concentration had a positive correlation with human activities.High correlation between Ca²⁺ and Mg²⁺ suggested their strong common source.Further analysis shows that H₂SO₄ participating in and accelerating the carbonate and sulfate mineral dissolution related to the above.Cl^-and NO^-3 with strong correlation were closely related to human activities indicating Cl^-and NO^-3 have similar sources of which most come from human activities.

Abstract:A systematically monitoring has been carried of soil percolating water in karst stony desertification area.The result showed that higher the degree of stony desertification is,the higher the concentrations of HCO^-3,Ca²⁺ and the value of calcite saturation index(SI_C) in the percolating water from rendzina area are.The concentrations of Mg²⁺ in water samples from yellow soil area showed the same trend.It maybe result from related soil and vegetation degradation.When vegetation degradation starts earlier than soil,the concentrations of HCO^-3,Ca²⁺ will decrease with the development of stony desertification due to the stronger reactions between water and soil.On the contrary,when soil degradation starts earlier than vegetation,the concentrations of HCO^-3,Ca²⁺ will increase with the development of stony desertification due to more time requirement for reactions between water and soil.

Abstract:This experiment was focused on the effect of organic fertilizer and planting density(60,75 and 90 thousand plants/hm²) on root growth and function of maize in field condition.The result showed that basal organic fertilizer reduced root length and surface area in 30-100 cm soil layer at pre-tasselling stage,but had no significant influence on root dry weight.The rate of root/shoot was significantly decreased because organic fertilizer dramatically increased the biomass of shoot.The influence of planting density on root growth was not significant.At waxen maturity stage,basal organic fertilizer restricted the distribution of root in 30-100 cm soil layer and at the position of 1/4 row space,1/2 row space,under plastic mulch,but had no significant influence on root/shoot.The trends of root length,root surface area and root dry weight were decreased as planting density increasing,especially in 0-30 cm soil layer and at planting position.The increase of planting density also decreased the rate of root/shoot,but increased the root function.Organic fertilizer also didn't show the significant effect on deferring senescence and had no significant difference in hydraulic conductivity of root system compared with the treatments without basal organic fertilizer.Root showed some flexibility by increasing water uptake function per surface area as planting density increasing.

Abstract:A case study on the quantity of aeolian sand erosion and deposition of fences with different height was carried out in the observation station of Chinese Academy of Sciences at southeast of Tengger Desert.The fences with different heights were deployed in the field.Combining the observed weather data and the data of aeolian sand erosion and deposition of barrier-free flat desert over the same period,it is concluded that the sand prevention effect of the fences with the height between 50 and 90 cm is better than others.And the fences with the height between 60 and 70 cm have the best effect.However,the quantity of sand deposition is different in the up and down wind.The quantity of sand deposition is with the fences of 70 cm in the upward wind while there was more sand with the fence of 60 cm in the downward wind.In the upward wind,sand is accumulated.In the downward wind,the intensity of aeolian sand erosion and deposition change with the height of fences.In practice,we must consider the properties of protection object.Only in this way can we achieve better sand protection effect.Besides,according to the pattern of cross section,the quantity and the intense of aeolian sand erosion and deposition,the sector of the front and rear of fences was divided into sand accumulation area,wind erosion area and balance area

Abstract:The dynamics of sap flow rates in apricot and related environmental factors in ecotone of agriculture and animal husbandry were observed using TDP sap flow measuring meter from May to September in 2009 in Wuqi County.The results showed that:(1) Abroad peak curve of diurnal sap flow change was occurred in apricot forest with the beginning of sap flow at 7:40 and the peak value at 12:00-14:00 and the quick declining at 18:30.And obvious stopping sign of the sap flow did not exist even at night.Moreover the sap flux from 8:00 to 18:30,which accounted for 60% of the sap flux of whole day,was the major part of sap flux.(2) The significant difference in the change of sap flow was detected in typical sunny and rainy day with a higher daily sap flow rate in sunny day than in rainy day.(3) The value of sap flow increased first and then decreased with time.And the highest value occurred in July with a mean value of 64.247 g/h,followed in June whose mean value was 58.139 g/h,while the lowest value of 49.156 g/h appeared in September.(4) The variation trend of sap flow in bough was similar to that in lateral branch.But compared to lateral branch,the bough had a higher sap flow velocity.The lateral branch was more sensitive to the variation of environmental factors than the bough and the response of bough to sap flow was slower than lateral branch and showed an obvious lag efffect.(5) There was significant difference in the sap flow rate of apricot among different positions.The sap flow rate in the upper side is higher than that in the middle part which is higher than lower part.(6) Environmental factors influenced the sap flow variances of apricot.The order of intensity of influence was as follows: air temperaturesaturation vapor pressurerelative humiditysolar radiationwind speedsoil temperature.

Abstract:Soil salinization has limited crop growth,development and production which is one of the most serious abiotic stress.Cultivation of salt-resistance crops is to solve a good way of the salinity problem.Through field experiments,salt-resistance capacity of rice grass-maize and its improvement effects on saline soil were studied.The results showed that fine rice grass-maize inbred line of adaptive saline soil have strong growth potential and salt-resistance,salt-resistance capacity is 11.76 g/kg.Based on good,strong,extra strong of growth potential,soil salt content were 15.7%,22.9%,34.5%,respectively.Therefore,after cultivating rice grass-maize,not only fine varieties have salt-resistance capacity,but also improved saline soil has a certain effect.

Abstract:The study on changes of soil fertilities was conducted in Michelia macclurei stands with different slope positions in 2004 and 2007.Compared with those in 2004,no significant changes in the soil density,capillary porosity,non-capillary porosity,total porosity and capillary moisture were observed in the upper-slope,middle-slope and lower-slope,whereas the natural water significantly increased in 2007.The pH value of the three positions decreased slightly,the contents of soil organic matter,total N and total K significantly increased,whereas total P content decreased in the three positions.The contents of soil hydrolyzable N and available P in the three positions and available K of the middle-slope and lower-slope significantly increased,and K of the upper-slope increased slightly.Soil physical properties changed with a non-regular pattern.The pH value and available P content of the three slopes were close to each other,the contents of soil organic matter,total N and total P were lower-slopemiddle-slopeupper-slope in 2004 and 2007.The content of soil hydrolyzable N of middle-slope and lower-slope was greater than that of upper-slope,and available K content of the upper-slope,middle-slope was smaller than that of the lower-slope in 2004,whereas it was lower-slopemiddle-slopeupper-slope in 2007.

Abstract:Due to erosion and other reasons,loess slope is uneven and a variety of micro-topographies formed,which result in differences in soil physical properties in different spatial positions in Northern Shaanxi Province.This paper investigated and analyzed the soil physical properties of the micro-topographies in loess hilly-gully region.The comparison of five types of micro-topography with undisturbed slope showed that the soil physical properties of collapse,gully,ephemeral gully and platform increased to a certain degree,but decreased in scarp.This usually occurred in 0-20 cm soil layer.Soil bulk density of the 0-20 cm soil layer changed in the following order: undisturbed slopeplatformscarpephemeral gullygullycollapse.Soil water content,maximum moisture capacity,field capacity and capillary moisture capacity showed relatively similar trend,higher values being recorded in collapse,platform,gully and ephemeral gully than undisturbed slope and scarp.The change of soil total porosity,capillary porosity and non-capillary porosity coincide with soil water retention.The analysis of grey correlation between the five types of micro-topography and the soil physical properties indicated that grey correlation followed an order of collapse,gully,ephemeral gully,platform,scarp,undisturbed slope.

Abstract:After the "5·12" Wenchuan Earthquake,plenty of loose soil materials accumulated in Jianping Basin of Longxi River,which is the main source material for debris flows initiation.Three large-scale debris flows occurred in Jianping Gully in 2009 and 2010.In contrast with the pro-earthquake conditions,the terrain and rainfall have not changed a lot and are appropriate for the initiation of debris flow,so loose materials can be regarded as the most significant impact factor for the debris flow characteristics and its development trend.The results based on the analysis of loose materials and its consolidation impact shows that debris flows in Jianping Gully will occur frequently in 5 years.The possibility of catastrophic debris flow will be high.In the next 5~10 years,the frequency and scale of debris flows in Jianping Gully will decline if there is no significant change for the rainfall and no strong earthquake,while large-scale debris flows can also occur under extremely rainfall with low frequency.

Abstract:With climate change,temperature increase may affect soil moisture movement and content.Take the typical paddy soil(Wushan soil) as a study case,the water characteristics curves and soil reservoir capacity of Wushan soil were studied.The results were as follows:(1) Main factors affecting the water characteristics curves were bulk density and clay content.Soil water content decreased in following order: plough layer,plowpan,waterlogging-hydromorphic layer,and gley layer under saturated condition and water suction as 1.50×106 Pa(wilting point).(2) Available water content had significant negative correlation with bulk density and clay content.But it had significant positive correlation with porosity.(3) Bulk density and total porosity were the main factors impacting the saturate hydraulic conductivity while the capillary porosity and pH were the second factors.(4) Total reservoir capacity of Wushan soil in plough layer was 91.48 mm.Available water reservoir capacity was 22.02 mm,and the flood detention reservoir capacity was 20.50 mm.Therefore,this soil had good water status which not only guaranteed high and stable soil productivity,but also had a regulatory function of water storage.

Abstract:In order to research the water-salt dynamic of platform fields by different isolation measures in coastal argillaceous saline land of Tangshan City,the salt content and water content of platform field by different isolation measures in 2009 are analyzed.Results showed that,water-salt dynamic of platform can be divided into three stages which were salt accumulated,desalinization and resalinization.There was a negative linear correlation between the water content and salt content,from April to October,the soil salt content showed a trend of "up-down",but the water content showed the opposite trend.The fact that the soil conductivity and water content of platform field which used isolation layer were lower than comparison platform field indicates that the isolation layer has obvious effect of salt resisting and draining.The best salt resisting isolation layer is that paved in the pattern of "double-section and a bar",and with slag,it should be widely used for its low cost.

Abstract:Soil samples from soil layers of 0-10 cm,10-20 cm and 20-40 cm in Picea crassifolia forest were collected,and the soil physical properties,soil moisture content and soil nutrient was analyzed and determined for these soil samples.The results showed that the soil bulk density values from different soil layer were all below 1.00 g/cm³,but increased with the depth;Soil porosity showed the same trend,and the soil porosity of different soil layers were above 63% percent,indicating a good ventilation.With the depth,the soil water content decreased,with a lowest value of 18.7%.Soil organic matter and soil total nitrogen content have reached extremely high levels,soil nutrient level was marked as grade 1;Total potassium level belonged to level 2;The total phosphorus was deficiency and belong to level 4 or 5;Mean soil pH is 7.5.Suggestions were made to strengthen the effective protection and management of Picea crassifolia forest ecological system in the eastern Qilian Mountains.

Abstract:Fish-scale pit is one of the soil and water control measures in the slope,and it is also a kind of slope afforestation site preparation methods.Due to its simple construction,storing surface runoff,the effect of maintaining soil and water,and promoting the growth of trees is relatively remarkable,it is widely application.In order to study soil moisture of fish-scale pits of different specifications by using fixed-point monitoring methods,soil moisture of fish-scale pits of four specifications in the Loess Plateau region of Northern Shaanxi Province was studied.Results showed that different specifications had a significant impact on soil moisture content.In terms of soil water on semi-sunny steep slope and extremely steep slope,specifications may be ranked in the descendant order of middle,large,small,smaller and contrast,in terms of soil water on semi-shady gentle slope and shady gentle slope,in the descendant order of large,middle,small,smaller and contrast.

Abstract:Based on the vegetation community survey of a 1 hectare plot in Forest Farm of Mulanweichang,and by using the mingling degree,neighborhood comparison and uniform angle index,the spatial structure characteristics of nature secondary forest in rocky mountain area of Northern China were analyzed.The results showed that Betula platyphlla was the dominant and constructive species of the tree layer,its mingling degree was low,but the mingling degrees of sub-dominant and associated trees were big.The mainly mixed forms of the stand were none-mixed or less-mixed,the average mingling degree was 0.400.The order of tree species neighborhood comparison was as follow: Larix principis-rupprechtii,Sorbus pohuashanensis,Quercus mongolica,Betula dahurica,B.platyphlla,Picea wilsonii,Populus davidiana,Pinus tabulaeformis and Acer truncatum.In the vegetation community,most of the trees were in the random distribution,but the average uniform angle index of the stand was 0.562,so the distribution pattern of the overall stand was aggregative distribution.According to the spatial structure characteristics of nature secondary forest,the tendency of community succession and some management advices were proposed.

Abstract:Real-time data sharing is a critical problem for land use data management under current network environment.Just as the XML is the standard criterion of information expression and data interchange for internet,GML,which is based on XML and developed by OGC,is the factual standard of the exchange,sharing and interoperability of spatial data in internet.Based on the national standard of GML 3.2.1,a GML application schema was designed for elements of land-use through the analysis of these elements and the relations among them.Based on GML and combined with C#,DOM and XPath,a inquiry system for land-use data has been developed.Under this system,many fundamental functions can be achieved such as the inquiry,displaying,browsing and publishing of land use data.The results and practice showed that GML can express land-use data better and facilitate the realization of land use data sharing.

Abstract:This paper introduced the basic principles of laser scanning technology(LIDAR),and specified the method of application the LIDAR to dynamically monitor gully erosion processes,which included measuring preparation,scanning survey process,point cloud preprocessing,coordinate transformation,TINs generation and soil loss estimation.Taking the experimental study on the gully erosion processes by simulating rainfall as a study case,dynamic monitoring method of gully erosion process using LIDAR was described in detail,which comprised field data collection,point cloud analysis,and mesh modeling.Comparison of the measured soil loss and the estimated soil loss showed that LIDAR technology has high accuracy to monitor soil erosion,and the estimating accuracy reaches to 96.85%.It suggests that the LIDAR should be combined with GPS technology to monitor gully erosion in field experiment.

Abstract:Two erosive soils,red soil and purple soil in Yangtze River basin,was selected as research objects,and K value was taken as indices of soil anti-erodibility,this paper calculated the soil anti-erodibility of red soil and purple soil under rainfall simulation experiments using universal soil loss equation(USLE).The results showed that the K values were 0.325 2 and 0.276 3 respectively for red and purple soil.Meanwhile,the K values were also calculated for red and purple soil using EPIC model,they were 0.313 8 and 0.266 8 respectively.Bases on the comparison of K values with two methods,the correction coefficient of EPIC model was obtained,the value was 1.04.

Abstract:An experiment about 4 kinds of absorbent polymers,they were conducted to study water absorbency and retention,relationship between water absorbency and particle size,and refrigeration effect on water absorbency and retention.The results showed that all these absorbent polymers had powerful water absorbency,but the water absorbing ability depended on the kind of absorbent polymers.Functional absorbent polymer(L) with maximum water absorption rate had a clear water absorbent peak in distilled water,while Hanbaobei(B) and nutrition(N) absorbent polymer with no obvious peak required more time to reach to the saturation point and water absorption rate of plant absorbent polymer(D) was greater than the one of B and N absorbent polymer during the initial stage,and became lower after that.The water absorbency was distilled waterwell watersoil solution,and no obvious difference in the later two,while L had the largest water absorbent rate,then B and N,D was the lowest,when they were in the same solution.At the same water absorption,the 4 kinds existed significant and insignificant differences periods,while the greater the water absorbency is,the longer time is required for complete dehydration,if they absorb water adequately.Besides,water absorbency was not only influenced by solution but also particle size.Moreover,refrigeration treatments had little effect on both water absorbency and retention.

Abstract:Due to the complicated causes,the poor understanding to debris flow and difficulties in prediction,a Fisher discrimination analysis model for forecasting the debris flow was developed according to the theory of discrimination analysis.Its basic idea is that a series of factor data related to the debris flow occurrence was projected to some direction and the data projected can be grouped as far as possible.The discriminant function was determined according to the univariate variance analysis,which requires smaller intraclass variance and larger interclass variance.And then new samples were sorted into some class according to this criterion.The proposed model is simple and run fast,and can predict the condition of debris flow in time.The case study showed that Fisher discrimination analysis model can improve the prediction accuracy of debris flow.

Abstract:The reasons and characters of soil and water loss that caused by 500 kV overhead power transmission lines(OPTL) construction were analyzed.On the basis of the analysis and combined the project example,a practical soil and water conservation system were presented according to the ecological environment in earth-rocky mountainous area of southwest.And in accordance with the problems that existed in soil and water conservation scheme process of 500 kV OPTL,some related advices were proposed.The research results will be helpful for supplement the soil and water conservation system in 500 kV OPTL in earth-rocky mountainous area of Southwestern China,and meanwhile,provided a reference for the similar project construction in the area.

Abstract:Reflectance characteristics of canopy and salinity parameters of soil were studied to investigate the relationship of reflectance of above-vegetation and salinity information of soil.The results showed that the maximum of canopy NDVI value presented at booting of rice.Throughout the whole growth stages,the canopy NDVI increased with the decrease of the whole salt,EC of surface soil,especially at booting stage.The NDVI of rice canopy was inversely related to soil Na⁺+K⁺ at jointing,booting and filling stages,except for the regreening stage.The NDVI of rice canopy did not presented significant differences with the increase of soil HCO₃^-,Cl^-,SO₂^4-,Ca²⁺ and Mg>²⁺ at the whole stages.Therefore,the total salt,EC and Na⁺+K⁺ of alkali-saline soil could be accurately predicted through measuring the canopy reflectance of rice from tillering to filling stage.

Abstract:Horizon slope is strata towards the slope strike vertical which is a good overall stability slope under natural state,In large-scale earthquake disaster areas of Wenchun County,it could found that instability model of horizontal slope under intensive earthquake are tension-crushing by large landslide survey.Instability mode is tension-trushing slippery under intensive earthquake.Based on Xinping village,Pingwu County landslide as an example,slope edge at the interface between tensile stress appears under the intensive earthquake,and the cracks apper unceasingly deepened,lower slope body appears stretch shear destruction because of the vertical and horizontal vibration,thus forming a uniform sliding surface,the crushing slippery slope body then cracks and slides down as "granular mixture" which rushes to slope bottom margin of peasant caused 9 villagers deaths,and it enters Zhengjia ditch blocked by the opposite mountain,then it moves like post-concussion and forms a barrier lake.These achievements are update in a certain sense to the traditional concept of stability evaluation of the horizontal slope.

Abstract:Based on the flood season(from June to September) precipitation data from 19 climatic stations within the Fenhe River Basin from 1959 to 2007,and using wavelet transform method,Mann-Kendall and other statistical methods,a time series analysis was made on the precipitation.The results showed that the precipitation in flood season in the Fenhe River basin showed a declining from 1959 to 2007,with an average velocity of-9.79 mm/10 a.However,the precipitation in June increased with a rate of 2.79 mm/10 a,while it decreased with a rate of-6.54,-2.69,-3.36 mm /10 a respectively in July,August and September.This indicated that the precipitation decreased in July and September was the main source of precipitation reduction in flood season.An abrupt change in the flood season precipitation appeared after 1978 when the basin underwent a period of little rain.From 1959 to 2007,there existed 8 to 15 years and 3 to 7 years cycles of precipitation series in flood season and the significant time-scale change were 2,5,10 and 12 year.But the 5 year scale was the main cycle because its oscillation was most strongly.According to the trend of the wavelet transform result,it can be estimated that there will more precipitation in flood season in the near future in the Fenhe River basin.

Abstract:Using biodegradable films are an efficient approach to reduce the white pollution by traditional plastic film which could remain in soils for hundred years.The degradation characteristics of biodegradable mulch films and its effect on the growth of maize were analyzed and tested.The results indicated that:(1) The degradation percentage of biodegradable mulch films was 1.26% within 60 days and 1.91% within 100 days respectively,and the remained film degraded greatly afterward.(2) No obvious difference has been detected between biodegradable and the common plastic films in the effect on the increase of the soil temperature.(3) The biodegradable mulch film could increase the leave area evidently,and 10.83%,9.38% and 7.94% increase has been observed above,at and below the corncob respectively,which would improve the growth.(4) The yield with degradable film mulching was about 18.7% higher than that without film mulching,but there are no obvious difference between it and the plastic film.

Abstract:In order to research the impact of lessive soil erosion under the freeze-thaw condition in spring thaw period,freeze-thaw temperature,freeze-thaw cycles,initial water content,snowmelt water flow,thaw depth were selected to study the effects of these five factors on soil erosion by using indoor artificial simulated snowmelt experiment.The results showed that the primary factor was snowmelt water flow.The erosion was mainly happened in the first 15 freeze-thaw cycles in spring thaw period,even though the cycles increase after that,the erosion wasn′t increase at all.There was not a significant linear relationship between soil moisture and erosion,but the erosion of relatively small initial soil moisture was greater than the larger amount of initial soil moisture.During the process of scouring runoff,the size of snowmelt water and the existence of soil frozen layer,which both affect the relations between the thaw depth and erosion.When the snowmelt water flow was smaller,the less depth of soil was thawed,the more amount of soil will be eroded,that appear a negative correlation between the two;however,when the snowmelt water flow was greater,that appeared a positive correlation.

Abstract:According to Guide of Carbon Sequestration Measurement and Monitoring of Afforestation Project of Green Carbon Fund in China.Carbon sequestration amount of Xanthoceras sorbiforlia forest planted was researched in Erdos City of Inner Mongolia.The results showed that Xanthoceras sorbifolia carbon content of every organs as follows.Carbon content of leaf,root,bark is 54.72%,45.26% and 54.58% respectively.After 20 years plantation of Xanthoceras sorbiforlia forest,the carbon reserve would be 81 911.53 t totally.In the process of plantation and tending,as a result of transport of seedling and fruit,water,fertilizer and other activities,carbon emission would be 834.60 t,and the net carbon sequestration would be 81 077 t.

Abstract:Soil erosion quantity and soil anti-erodibility can be reflected by the amount of surface residual particles with wind erosion.It is of great importance to precisely extract particles content on earth surface.Based on digital image processing technology,the extraction of soil particles on wind erosion surface in northern foot of Yinshan Mountain has been done.The result showed that the particles area processed by ERDAS IMAGINE 9.0 was smaller than that processed by ArcGIS 9.2,but there was a remarkable linear relation between them.We can use this relation to compensate particles deficiency area.The fractal dimension obtained by means of particles equivalent area and equivalent perimeter was 1.418 4.The soil particles condition reflected by this fractal dimension on research region was in accordance with that real condition.With image processing software,we can extract accurate surface particle information.It can provide a foundation for future desertification monitoring,also,it was greatly meaningful for us to swiftly and exactly valuate the degree of soil wind-erosion and land desertification.

Abstract:The forest carbon storage estimation methods based on the forest inventory data(FID) are important in assessing forest carbon budget in terms of landscape,regional,and national scales,and play an important role in studying terrestrial ecosystem carbon cycle and global changes.The vegetation carbon storage in forest ecological system is usually calculated by multiplying forest biomass of the forest ecological system with its biomass carbon content,and in the world,the coefficient commonly is 0.45~0.55.There are basically four methods for forest biomass estimation based on FID: IPCC method,a constant BEF of biomass expansion factor method,biomass expansion factor continuous function method and biomass experience(regression) model method.The quantitative methods of forest carbon storage estimation based on FID of forest vegetation were reviewed.The problems related to the methods were pointed out,and improvement proposals were put forwards for future forest carbon storage estimation methods.In forest carbon storage estimation,remote sensing techniques need to be stressed,the carbon flux in the forest inventory need to be increasingly employed and the inversion models fitted to the actual situation in China need to be developed in the future.

Abstract:SRTM and ASTER GDEM are public DEMs(digital elevation models),which are used widely in terrain analysis.Elevation is the base information for DEM,and slope is one of the most important DEM terrain representation factors.Based on the actual measurement data of elevation and slope,we measured the error of the DEM and slope using the methods of correlation analysis,accuracy analysis,slope spectrum analysis and regression analysis in the Northern Tibet Plateau.The results showed as follows:(1) There was some small errors in the elevation data derived from SRTM and GDEM.The Pearson correlation coefficient between elevation data and the actual measurement is 0.975 and 0.994,the root mean square error(RMSE) 57.381 and 31.106,the accuracy ratio(AR) 2.089 and 1.976,and the relative mean error(R_ME) 1.1% and 0.7%.(2) There is more error with the slope data derived from SRTM than from ASTER GDEM.Compared with the actual measurement,their Pearson correlation coefficient is 0.878 and 0.946,the root mean square error(RMSE) 4.014 and 2.395,the accuracy ratio(AR) 1.238 and 1.034,and the relative mean error(R_ME) 21.5% and 5.5%.(3) The slope spectrum is a new way in terrain analysis,and we found that the accumulative frequency slope spectrum can visually indicate errors in slope derived from DEM.

Abstract:The simulating test was conducted to analysis how waste fiber felt mulches with different surface density affected moisture evaporation from soil surface.The test was using waste fiber felts with the density of 100,200,300,400 and 500 g/m²,compared with bare surface as contrast.The result indicated that the waste fiber felt mulches would inhibit soil moisture evaporation efficiently.Inhibitory effect of the evaporation was related with the surface density obviously.The more surface density resulted to a better inhibitory.The inhibitory effect would keep to a stable level when surface density of waste fiber felt mulches reached a certain value(400 g/m²).

Abstract:The assessment model of rocky desertification was built using remote sensing technique,geographic information system technique and principal component analysis method,which was used to assess the present situation of rocky desertification in typical karst mountain area of North Guangdong Province based on TM images of 2004.The results showed that rocky desertification was still severe in study area,the area of most severe,severe and moderate grades of rocky desertification took up 74.03% of the total rocky desertification land,and these rocky desertificated lands mainly distributed in the middle part of Yangshan County and the north west part of Ruyuan County.The assessment results showed little difference with the data of field survey,which indicated that it was a feasible method to assess rocky desertification with the information of rocky desertification landscape extracting from RS images using principal component analysis method with ArcGIS software.

Abstract:To build China national sustainable communities(CNSCs) is an important action in the sustainable development strategy carried on in China.The general situation of the development of CNSC and thecalculating method of sustainable development level are summaried.Taking 14 prefectural-level cities for example,choosing 19 assessment indices from four aspects of economic,social,resource and environment,this paper calculated the developing indexes about every subsystem,the degree of coordination and the sustainable development level.According to the degree of coordination and sustainable development level of every city,three different sustainable development types are distinguished by adopting the method of clustering analysis,those are:(1) the degree of coordination and sustainable development levels are all higher than others(C_hS_h);(2) the levels are all lower than others(C_LS_L);(3) the levels are in the middle of C_hS_h and C_LS_L(C_mS_m).The CmSm is further divided into two subtypes by the economic and social development level,the one is very prominent,the other is almost balanced.The geographical distribution of the different patterns is also illustrated and the leading direction of future development is suggested at last about different types of CNSCs.

Abstract:An assessment on the economic value of ecological forests in controlling flood,producing surface runoff,soil and water conservation and fertility improvement was carried out in Guangdong Province.The results showed that the total economic value of eco-forests to soil and water conservation and water resources improvement was 16 445.36 millions RMB in Guangdong Province in 2010,of which the economic value in producing runoff during dry period,fertility conservation,controlling flood and soil conservation were 6 205.60,5 343.17,3 034.59 and 1 861.99 millions RMB respectively,which accounted for 38%,32%,18%,12% of the total value of ecological forests.The total economic value of the eco-forest in soil and water conservation in Shaoguan City,Heyuan City,Qingyuan City and Meizhou City accounted for 55% of that in Guangdong Province.

Abstract:With the development of research on eco-environment field,the relationship between soil and water loss and regional economic development has become the new academic focus.The environmental Kuznets curves and regression analysis model are adopted to study areas of soil and water loss and GDP per-capita in Fujian Province from 1995 to 2008.The results showed that the relationship between soil and water loss and economic development possessed the characteristic of environmental Kuznets curves.The current stage of economic development could decrease the soil and water loss and had positive effects on soil and water conservation.

Abstract:Relationship between normalized difference vegetation index(NDVI) and climate factors were analyzed in the south of Gurbantunggut Desert using the NASA/MODIS data(from 2000 to 2009) and meteorological data in Fukang City.The results showed that the annual average temperature,precipitation and NDVI has increased in the past 10 years.The monthly variation of NDVI showed a slight double-peak pattern,with the first maximum in May,the second maximum in August and the minimum in February.The rescaled range analysis of NDVI showed that yearly and seasonal temperature,precipitation NDVI will increase continuously in the future,and NDVI change will coincide with the change in temperature and precipitation.

Abstract:Take Tianjin City as a representative of cities in North China,an investigation is conducted on the wild flowers in urban areas from 2005 to 2010.The ecological habits,life forms and distribution of each species were carefully studied,and six different distribution patterns(single,linear,scattered,assembled,radial and climbing patterns) were detected.After the careful analysis on the characteristics of each distribution pattern,the possible use of these wild flowers in urban gardening was discussed,hopefully this can provide some guidance on wild flower use in urban gardening.

Abstract:The purpose of the paper is to set up a system of land use main function zoning,to provide basis for the regulation and to control the regional land use.Based on the conception model of combination of coordinate and attribute,this paper bring spatial coordinate,spatial relationship and attribute features into the unitive model of spatial computation.A system of main function zoning of regional land use is established and the 19 townships of Yubei District in Chongqing City are divided into 4 land use main functional zones.(1) Northern New District,Shuangfengqiao Street and Huixing Street belong to optimized development zone;(2) Longshan Street,Longxi Street,Longta Street,Yuelai Street and Shuanglonghu Street belong to important development zones;(3) Xinglong Town,Gulu Town,Dawan Town,Longxing Town,Yufeng-shan Town and Tongjing Town belong to moderate development zones;(4) Luoqi Town,Shichuan Town,Muer Town,Dasheng Town,Cizhu Town belong to control development zones.The result of spatial cluster analysis simultaneously reflected the characteristics of spatial location and attributes,meanwhile spatial cluster analysis could reflect the spatial proximity which can make the clustering results more objective.

Abstract:Surface pollution is the main threat to water quality of Danjiangkou Reservoir.In order to analyze the amount and form of surface pollution in Danjiang-Hanjiang watershed in Shaanxi Province,a study was carried out,and the amounts of the main surface pollutants transported into the rivers and their contribution rates were calculated using the methods of statistical investigation,parameter calculation and comparison analysis.The results indicated that the annual amounts of COD_cr,ammonia nitrogen,total-nitrogen,and total phosphorus transported into the two rivers were 103 053,19 851,213 453 and 39 838 t respectively.Domestic sewage,human excrement and urine are the main source of COD_cr pollution.Soil and water loss is the main source of nitrogen and phosphorus pollution.The amounts of surface pollutants transported into rivers are related to the factors such as pollution sources baseline,pollutant contents and pollutant scatter degree.It is suggested that more efforts should be invested in soil and water conservation,new countryside construction and extension of ecological and clean small watershed,etc.

Abstract:The heavy metal content in the sediment of Wangjiaya Reservoir in Baoji City were determined by using X-ray fluorescence spectrometry and their ecological risk were assessed by using the potential ecological risk index.The results indicate that the average contents of As,Co,Cr,Cu,Ni,Mn,Pb,V and Zn in the sediment were higher than the soil background values of Shaanxi Province.The accumulation coefficient of Cu was the highest among the studied heavy metals,while Zn was the lowest.The heavy metal element distribution in the sediment had the similar horizontal character,which was high content in the reservoir centre,low values in the reservoir up-reach.The results of potential ecological risk assessment showed that the ecological risk degree of the heavy metal pollutants was moderate,and the highest comprehensive ecological risk was in section 5(in the middle reach) and lowest was in section 8(in the upper reach).The order of individual potential ecological risk was AsCuNiCoPbVMnCrZn.As had the moderate ecological harm and other heavy metals have lower ecological risk.

Abstract:Distribution and characteristic of Cd,Cr,Cu,Hg,Pb,Zn,Ni of urban dust were analyzed on regional scale coming from forty-seven cities.The results showed that heavy metal concentrations were divided into five grades,and change from one to four times standard deviation.In space scale,they were high in western and southern,and low in eastern and northern,and reduced from southwest to northeast.The order of heavy metal content in each region was Southwest ChinaNorthwest ChinaSouth ChinaEast ChinaNorth ChinaCentral ChinaNortheast China.In addition,some elements,spatial distribution was consistent with the stepped topography of China.Soil background and human activity were important factors,the former mainly influenced North China,Central China and Northeast China,the latter played an important role in Northwest,Southwest and South China.The order of disturbance on heavy metal was CdHgZnPbCuNiCr.

Abstract:According to the distribution of grain for green program counties and investigators in Northwest China and Inner Mongolia Autonomous Region,793 rural households of six provinces are conducted a questionnaire survey.Main achievements and trends on grain for green policy are analyzed,and the evaluation of households to grain for green project is summarized.The conclusions of this survey and policy recommendations are proposed.The results show that grain for green project has significantly improved the ecological status of the study area,increased the eco-awareness of households and the levels of household livelihoods.Households support the policy of grain for green policy and will further carry on grain for green.Because farmers are highly dependent on subsidies,the tendency of deforestation and re-cultivation would be carried out in the case of lower subsidy policy to the program.Increasing subsidies,expanding the area of grain for green,providing technical support and developing the follow-up industry are the common aspiration to current farmers.

Abstract:In order to study the effects of slope on land use/land cover distribution and its dynamic change,taking Chang′an District of Xi′an City,Shaanxi Province as a case study area,classified the slope derived from the digital elevation model,and then a spatial overlay analysis has been done for slope map and land use map derived from remote sensing maps.The results showed that cultivated field,construction land,water mainly distributed in areas with slight slope,and woodland,grassland distribution on slope showed a normal distribution.The percentage of different land use types in same slope area was essentially same in different years while different land-use change existed in different slopes.The conversion of other land use types to construction land and the farmland mainly occurred in the slight slope area while the conversion to forest and grassland showed a normal distribution in the whole range of slope.The slope is an important factor to land use/land cover distribution and land use pattern.

Abstract:Based on investigation,greening structure on riparian zone of Xuzhou area is divided into five categories,and Shannon-Wiener diversity index of the riparian vegetation is quantified.The study shows that there are significant differences between urban area and rural area in the riparian structure.The riparian structures in urban area are dominated by the types of garden and high-grade wall,and plantation is the main type of riparian structure in rural area.The diversity of woody plants in rural area is similar to that in urban area.But in rural area,there is higher herb diversity than the one in urban area.The riparian structure types have remarkable effects on the riparian vegetation diversity.The diversity of trees varies slightly among different structure types.The type of high-grade wall is significantly higher than other types in shrub diversity,and the type of plantation takes highest grass diversity.The riparian width gives a significant impact on riparian structures.At last,some suggestions on the transformation of riparian zone in Xuzhou area were given.

Abstract:The article attempted to provide a preliminary draft of spatial functional planning for the mainstream region of Weihe River basin.Firstly,the study made a comprehensive view of the region from three aspects of social economy,resources and environment,including population,GDP,traffic,land use,water resource,environmental capacity,ecological fragility,natural disaster and ecological significance.Secondly,with county-level GIS data and the method of factor analysis,it evaluated both status quo and prospect of each unit′s development.And then,the study worked out a draft planning of integrated function zoning for the study region.Finally,according to the different types of development in Weihe River basin,some measures and policies are put forward for regional development from infrastructure,public product,ecological environment protection,etc.The draft is very conducive for the space governance in the mainstream region of Weihe River basin.

Abstract:Using the methods of remote sensing,geographical information system(GIS),landscape ecology and analytic hierarchy process(AHP),this paper analyzed the change of landuse pattern and its ecological and environmental effects in arid area of central Ningxia Hui Autonomous Region from 1978 to 2007 based on the MSS image in 1978 and Landsat TM/ETM images in 1987,1996,2007.The results showed that areas of farmland and construction areas increased in the past 30 years.The newly-increased farmlands mainly came from unused land and grassland,while the newly-increased lands for construction mainly came from farmland and unused lands.At the same time,the forest land and grassland decreased from 1978 to 1987,and increased from since 1987.The sources of increased area were primary farmland and unused land.These changes caused great changes in landscape such as landscape fragmenting and heterogeneity and declining of environmental quality from 1978 to 1987.The index of environmental effect was only 0.118 in 1987.After that,with implementation of the regulating and controlling measures,prohibiting graze policy and hydraulic engineering,more farmland and unused land have been converted to trees and grasses,the vegetation cover increased,and the landuse structure was adjusted.This led to the gradual improvement of environmental quality since the middle and late 1990s by environmetal strategies.

Abstract:Xixi National Wetland Parkin Hangzhou City is the only national wetland park which includes urban wetland,agricultural wetland and culture wetland.Not only does it have tourism and education functions,but also can protect the ecosystem and regulate climate.Compared with the natural reserves,Xixi National Wetland Park is more easily affected by human activities.This paper selected gate establishment,pool improvement,boat cruising and pedestrian as study objects,and an investigation is carried out to study their impact on water quality from March to December in 2009.The results showed that gate establishment and pool improvement could improve the water quality,and boat cruising and pedestrian has little impact on the water quality.

Abstract:Collection of water resources fees is of great importance to sustainable use and optimum configuration of water resources.Based on the analysis of current situation of water resources fees collection in Chongqing City,this essay disccussed the existing issues of fees collection and put forward the following suggestions on the methods of fees collection on water resources in Chongqing City:(1) To revise or release laws and regulations related to water resources fee collection and management;(2) To increase the standards of water resources fees,and adopt different collection standards for industrial water and domestic water;(3) To collect fee on geothermal water and mineral water resources.

Abstract:Taking a reclaimed ecosystem in dump of Pingshuo opencast coal mine for 20 years as the research object,the implementation effects of ecological rehabilitation technologies were analyzed including soil reconstruction,screening pioneer species,vegetation succession and changes of animal,microorganism and soil nutrient.Results showed that the particular reclamation technologies-dump surface were covered directly by loess parental material,then ripened by fertilizing,were developed in Pingshuo mine.Many vegetation configuration modes were screened with Caragana korshinsk×Robinia pseudoacacia×Pinustabulaeformis,Robinia pseudoacacia×Pinus tabulaeformis and Robinia pseudoacacia×Hippophae rhamnoides etc.With the increasing of reclamation years,wild species invaded,soil seed bank gradually formed and species diversity has increased.Moreover,vegetation communities tended to stability and animal,microbial and soil nutrient presented the increasing trend.All these changes indicated that the ecological system have entered a normal succession process.But duo to the influence of special habitat and natural objective conditions,some problems such as diseases and pests,intraspecific and interspecific moisture competition etc,have resulted in vegetation degeneration.So ecological management of plants succession needed to be study in detail.