Abstract:Quantifying topographic feature of watershed synthetically and scientifically is one of key problems forwatershed soil erosion prediction model that is used everywhere.Fractal theory has provided new solution for study on quantifying topographic feature of watershed.Based on fractal theory and the general model of small watershed quantitative coupling relationship between topographic fractal feature and sediment yield was studied by simulation rainfall experiment,high precise photogrammetry and GIS technology.The results showed that the process of soil erosion and sediment yield of watershed model took on phase characteristic with early phase,active phase and stable phase according to relative sediment transport rate,which avoided the influence of rainfall characteristic on soil erosion and sediment yield process of watershed model.During the different phase,the variation trend of fractal information dimension (D_i) of watershed model topographic feature was similar to that of relative sediment transport rate(S_r) of watershed model,which took on rising firstly,then falling down and becoming stable.Relative sediment transport rate (S_r) of watershed model and the fractal information dimension(D_i) presented positive correlation with power function.The correlation exponent r~2 was 0.742 3.Fractal information dimension(D_i) of topographic feature of watershed model has perfectly described the influence of topographic feature on soil erosion and sediment yield process of watershed model,and it can be as the integrated index of quantifying topographic feature for soil erosion and sediment yield prediction of watershed model.

Abstract:Soil and water loss in expressway is representative type of man-made accelerated erosion.The type,situation and intensity of soil and water loss have direct relation to the construction of principal part of the expressway.The eroded environment is composed of erosive forces system,eroded object and eroded unit.Soil and water loss showed discrete distribution along the expressway in space and have great identities with the construction of principal part in time.Based on it,the eroded units and soil and water loss characteristics in the scope of duty on prevention of soil and water loss were studied on classification by surveying different expressways in which some have been completed,some are under the construction and some are planned to be built in Chongqing.Besides the features of harmful geology structure stability along expressway and the key dominant factor were discussed on classification.At last the environmental sensitive area in expressway also was discussed to provide theoretical support for prediction of soil and water loss,arrangement of soil and water conservation measurement and monitor of soil and water loss.

Abstract:Erosion characteristics of two kinds of typical aeolian soils in Horqin Sandy Land were studied using portable wind tunnel. Results show that soil loss rates of flowing sand and farmland samples increase in power function with increasing of wind velocity. The threshold wind velocity of air-dried farmland sample is about 3.7 m/s, while the velocity of flowing sand is about 4.3 m/s. The soil loss rate of farmland sample is larger than flowing sand sample in a range of a lower wind velocity, but soil loss rate of flowing sand sample is larger than that of farmland sample when wind velocity is more than 5.7 m/s. In addition, the difference between the soil loss rates increases with increasing of wind velocity. Soil loss rate decreases in power function with increasing of soil water moisture. Anyway, loss rate of flowing sandy sample decreases more rapidly than that of farmland sample. Threshold wind velocity of flowing sand sample linearly increases with increasing of soil water moisture, while the velocity of farmland sample increases in quadratic equation with increasing of soil moisture. The difference of wind erosion characteristics of the soils is attributed to different properties of the soils. Increasing of soil water moisture can efficiently decrease wind erosion in the region in erosion duration.

Abstract:对毛乌素沙地南缘半流动沙地、新垫土改良地和改良4年的麻黄地土壤理化性质的研究结果表明：垫土对沙地土壤有明显的改良作用，细粒物质增加，持水能力提高，0～20cm平均粒径由0．24～0．28mm降到0．14～0．18mm。土壤中有机质平均含量为0．107％、全氮为0．0113％，速效氮为11．522mg／kg，分别是半流动沙地的1．67．1．67，2．75倍。改良后通过4年种植的麻黄地土壤得到进一步发育，20～40cm层粉沙含量占到10．38％～18．38％，是新改良地的7．98～14．94倍。有机质平均含量为0．208％，全氮为0．0183％．速效氮为17．658mg／kg，分别是半流动沙地的3．25，2．71．4．21倍，且有机质和全氮含量在30～40cm深处出现峰值。

Abstract:在云南19.5°红壤坡耕地上设置水土流失综合治理试验样方,观测水土流失控制效果。结果表明,各观测样方的地表径流量、土壤流失和养分流失按照裸地(CK1)>传统单作玉米区(CK2)>植物篱玉米秸秆覆盖区>植物篱麻袋覆盖区>植物篱牧草活覆盖区依次降低。2004年较2003年降雨和径流明显增加,各处理土壤养分流失的增幅显著低于土壤流失的增幅;土壤养分流失与施肥量显著正相关;植物篱 覆盖区的养分利用率比传统单作玉米区极显著提高,养分利用率与施肥量负相关。植物篱麻袋覆盖区和植物篱牧草活覆盖区,地表径流减少22.7%~34.0%,土壤流失减少27.1%~67.6%,养分流失减少36.8%~77.8%,养分利用率提高27.9%~45.2%;保持水、土、肥和提高养分利用率的效果都优于植物篱秸秆覆盖区。

Abstract:以黄土高原中部泾河及其7个子流域为研究对象，选取了流域内8个水文站33年的径流量和输沙量以及30年的降水量数据，同时对2002年的MODIS数据进行分类处理，分析了不同流域的水沙变化差异及其地表覆被类型特征。结果表明：泾河流域近50年来的输沙量略有下降，而径流量减少比较显著；泾河及其7个子流域的水沙变化和9种地表覆盖类型空间格局的差异显著；地表植被类型较好的流域，径流量相对较大而输沙量相对较小，且径流量与输沙量的起伏波动较小，反之则流域的径流量相对较小而输沙量相对较大，且径流量与输沙量的变化明显。

Abstract:Based on statistical and hydrometric data,a study has been made of the check dam construction and its sediment-trapping effects.The area(Ac) of the land created by the sediment trapped by check dams is used as an index for soil and water conservation beneficial of check dam measures.It has been found that the rate at which Ac increases attained the maximum in the 1970s,and then decreased in the 1980s,and further decreased in the 1990s.The sediment reduction beneficial by check dams has been estimated using hydrological approach.The results show that sediment reduction beneficial increased rapidly in the 1970s,attaining the maximum in the late 1970s and early 1980s,and then declined.The yearly increment of Ac increased from the mid-1960s,attaining the maximum in the early 1970s,and then declined.Since the construction of check dams failed to be continued,the yearly increment of Ac showed a greatly decrease in the late 1970s and in the 1980s,and the sediment reduction beneficial of check dams declined due to the filling-up of most existing check dams.As a result,following a significant decrease in the 1970s and 1980s,the sediment yield of the Wudinghe River showed an increasing trend from 1986 to 1996,mainly because the check dam construction failed to be continued after the old ones were filled up.Hence,it is suggested that the construction of check dams should be strengthened for a sustainable sediment reduction beneficial,so that the reduction of sediment to the Yellow River could be sustained.

Abstract:The concept and significance of the soil loss tolerance has been reviewed firstly, and then the shortcoming of the loss tolerance criteria being used in the black soil region of northeast China has been pointed out. In referencing to the experience in the world, the soil-forming process, the type and intension of soil loss and the depth of soil are the primary factors to constitute the loss tolerance criteria in the black soil region of northeast China, and especially, the high-point of soil loss control at present and a period of time in the future has been used as a most important factor for loss tolerance criteria constitution. Comprehensive analyzing the investigation result of soil and water conservation practice at 72 small watersheds in the black soil region of northeast China, the criteria of soil loss tolerance and soil loss control has been constituted for the primary soil erosion typical areas.

Abstract:选取黄土区大型排土场不同复垦年限的植被为研究对象,分析了陡坡地(36~°42°)3种典型乔灌草植被根系的剖面分布特征及不同复垦年限(1~14年)不同复垦模式植被根系对土壤抗蚀抗冲性的影响。结果表明,与原地貌土壤剖面根系分布不同的是,排土场乔灌草的根系分布(Φ≤1 mm)从10 cm土层开始,随着土层深度的增加,呈现出幂函数减少的趋势;干土层出现的深度依次为刺槐林地>草地>柠条林地;不同复垦年限不同复垦模式(1~14年)55个样点的统计分析表明,土壤的抗蚀性指标和抗冲性指标都与根系密度在极显著水平上呈直线关系。

Abstract:Hole-ephemeral gully is a media process between ephemeral gully and gully.It has very important significance for us to understand in advance the laws of gully erosion.However,little research on hole-ephemeral gullies in prior literatures has been done.A small catchment on the Inner-Mongolian Plateau is regarded as a case study and Global Position System(GPS) is used to measure the morphology parameters of hole-ephemeral gullies and topography of the study area.It discusses relative characteristics of hole-ephemeral gullies and analyzes the relationship(S-A)between slope gradient(S)at gully head and upslope drainage area(A)for hole-ephemeral gullies and the relationship(V-L)between lengths(L) and erosion volumes(V)for hole-ephemeral gullies in order to promote the studies on hole-ephemeral gullies.

Abstract:In order to filtrate the feasible tillage technology in sloping farmland of Yuxi dryland area,four tillages including reduce tillage,no-till,subsoiling tillage and conventional tillage were studied on the content of soil water and soil nutrient and its utilization and run off complexion.The results showed as following:with subsoiling tillage and no-till,the soil water storage were increased and the content of the soil organic quality,N,P and K content were evidently higher than conventional tillage,especially the effects of the whole N and alkali solution N in upper soil layer and the available P and soon effect K in deeper soil layer were more obvious,and the times and content of water run-off were reduced effectively,and soil nutrient run-off were reduced too.Therefore,the use efficiency of soil water and the production efficiency of soil nutrient can be improved after with subsoiling tillage and no-till.Compared with conventional tillage,the water use efficiency,the N,P,K production efficiency,the yield of winter wheat and the economic benefit increased by 16.37%,17.40%,19.80%, 19.44%,23.22% and 29.36% respectively after with subsoiling tillage and those items also improved by 10.62%,10.27%,12.54%,12.19%,15.38% and 21.13% after with no-till.

Abstract:Organic matter and cation exchangeable capacity of sandy soils tended to decline following the conversion of forestland to agricultural uses. Nitrogen and potassium induced by fertilization were not significantly accumulated in the topsoils, they could be rapidly transported to groundwater or runoff to surface waters. However, phosphorus could be significantly accumulated in sandy soils as extractable forms that were active and could be gradually released into groundwater and surface waters. Long-term application of fertilizers to the sandy soils influenced significantly groundwater with increased concentrations of P and N. As compared with other soils, nutrients in the sandy soils could be easily transported with water. Significant runoff of N and P was often noted in the fertilized fields during heavy rainfall. It was recommended that application of high rate of fertilizers should be avoided, and any fertilizers should be avoided to apply in the sandy soils before the rain.

Abstract:Grassland soil samples were collected respectively in the areas without obvious rocky desertification,the moderate rocky desertification region and the intensive rocky desertification region of the western Karst district,Guizhou province.The contents of soil organic matter(SOM) and different forms nitrogen were analysed.The variety range of SOM and different forms nitrogen is the widest in the intensive rocky desertification region and it is the narrowest in the areas without obvious rocky desertification.Analysis of variance indicated that hydrolysable and anmio-acid N content was significant between the moderate rocky desertification region and the areas without obvious rocky desertification,SOM and the other form nitrogen content wasn't significant in different regions.Based on the problems which were encountered in the research process,it put forward some subjects which would be studied in the research of rocky desertification immediately.

Abstract:Nitrogen non-point sources pollution researches from purple soil cropland were carried out in Yanting agro-ecological station(CAS) watershed.Nitrogen output and transportation observation was conducted in surface runoff plots of different purple soil farmlands.Nitrogen concentrations and forms of runoff were monitored twice a month with two replicates.Nitrogen pollution load was calculated based on above observed and investigated data.Impact of non-point sources pollution of nitrogen on the environment was discussed here.Results showed,In the upland runoff,particle nitrogen contributes 35% to total nitrogen(TN).Average concentration of total nitrogen in farmland runoff was in following sequence: SNTRCS(seasonal no-tillage ridge cropping system)

Abstract:以一东北黑土区典型漫岗坡耕地为研究对象，测定不同侵蚀程度地形部位的活性碳组分，以分析土壤侵蚀对活性碳组分的影响以及沉积区侵蚀碳的归宿。研究结果表明：各地形部位表层黑土（0～20cm）水溶性有机碳（WSOC）含量介于14．6～20．0mg／kg之间，低于总SOC含量的0．15％WSOC在沿坡迁移的同时，向下淋溶也很显著。MBC含量为121．5～583．6mg／kg，占总SOC的1．0%～4．7％。Min—C变化范围为52．8～115．3mg／kg，土壤Min-C差异主要集中在表层。土壤侵蚀显著降低侵蚀部位表层土壤Min-C、WSOC和MBC含量，沉积区土壤MBC、Min—C含量及其商值较高，而WSOC却无显著累积。相关关系表明，表层土壤Min—C、WSOC和MBC均于总SOC含量呈显著正相关。初步的研究结果认为侵蚀物质的输入增加沉积区表层土壤微生物活性和土壤碳的矿化潜力，常年处于氧化环境中的侵蚀碳可能被矿化而难以累积。

Abstract:A field trial was carried out to study the effect of different K supply on the grain yield,K acquisition and utilization of eight rice cultivars.Results showed that there were significantly genotypic variations in rice grain yield,K utilization efficiency and shoot K accumulation at different growth stage under two different K supply.Compared with normal K supply, rice grain yield and shoot K accumulation were decreased,and K utilization efficiency was increased under low K supply.Correlation analysis showed that under low K supply rice grain yield was positively correlated with K utilization efficiency,shoot K accumulation of both growth early stage and growth mid-stage(p<0.05),and under normal K supply rice grain yield was positively correlated with K utilization efficiency and shoot K accumulation of growth early stage(p<0.05).Therefore,screening and breeding rice genotypes with higher K utilization efficiency and higher ability to accumulate K at growth early stage would probably be one of alternatives to alleviate the K deficiency of paddy soil in south of China.

Abstract:Continuous soil nutrient data is the basic data of soil information system, soil nutrient spatial interpolation study becomes very important because it can affect the data reliability of soil nutrient data straightly. In this study, soil available kalium data, Zhouzhi county, Shaanxi province, is sampled and got the interpolation map of available kalium with OK, IDW,Spline and TSA according to interpolating sampling points. The cross validation results showed that OK is the best which used spherical model in these methods; although Spline and IDW could also produce fair and reasonable results, both of them were sensitive to sampling density, interpolation result appeared large prediction errors in those regions which had exiguous sampling points,

Abstract:Soil nutrients is one of the important signs and indicates of soil fertility,land evaluation and land management.In based on spatial statistical analysis and GIS in the farming-pastoral zone,the spatial features of soil nutrients were analyzed.Spatial autocorrelation showed that the Moran's I of soil organic matter is sensitive to the scale,but total nitrogen(TN),P and K is not sensitive to the scale.The space of organic matter,TN and P is positive at 0~60 km and negative out of 60 km.The effective range of K(33 000 m)was larger than TN(11 000 m),and P(3 000 m).The effective range of soil nutrients is negative to the fractal dimension.soil organic matter and K were fitted by exponential model,or spherical model was better for TN and P.

Abstract:From the aspects of physics and chemistry,the process and characteristics of soil quality degradation in Guizhou karst area were discussed.Results showed that in the rocky desertifcation process of soil,a series of physical and chemical properties worsened associated with losses of soil fine particle materials,including bulk density raised,total porosity reduced,aeration and non-capillary porosity increased,water-holding capacity relented,soil organic matter,total N and P contents decreased.the majority of silt and clay contents(<0.05 mm) were removed,could result in the decreases of soil organic matter and total N contents.Dusiturbances induced by farmers(i.e.irrational land cultivation and vegetaion was destroied) was the main force of soil quality evolvement.The models of soil quality degaradation process was gradual degradation course and leap degradation course.

Abstract:The indoor soil column simulated experiments was adopted to study the effects of reclaimed water irrigation on soil physicochemical properties.The results showed that soil water diffusivity and saturated hydraulic conductivity was influenced by reclaimed water irrigation frequency,soil water diffusivity and saturated hydraulic conductivity reduced in short period,but with increasing of irrigation frequency,the two parameters would increase.With increasing of irrigation frequency,pH decreased,organic content and total dissolved solid increased,ion concentration in soil solution changed obviously.After irrigation 5 times,the total dissolved solid of 0~10 cm soil layer was 0.107%,and others was below the limit of 0.1%;in the 0~10,10~20,30~40 cm soil layers,ESP was in the range of 5%~10%,in the 20~30 cm soil layer,ESP did not changed.The effect of reclaimed water irrigation on soil secondary salinization and sodicilization was not significant.

Abstract:对合川市紫色土区7种农林复合经营模式的土壤理化性状进行了试验研究，结果表明；与纯林相比，农林复合生态系统能够有效地改善土壤养分在垂直空间上的分布，对不同深度土壤的理化性状均有所改善，特别是20～40am土层；不同复合年限的系统对土壤的改良效果不同．复合4年的枇杷一西瓜复合系统效果明显好于复合2年的系统．前者0～20cm土层的全N含量比后者高41．67％，20～40cm土层的有机质含量比后者高43．23％，40～60cm土层的全K含量高23．41％；不同复合品种的系统同样也有不同的效果，柚子—苋菜系统对土壤物理性质的改良效果最好．该系统土壤中的N素和P素含量高于柚子—粉葛系统，K素含量则低于柚子—粉葛系统，而柚子—玉米复合系统对土壤的改良效果总体上不如前两个系统。

Abstract:Through field investigation and experiment analysis, the effects of four management types of Pinus koraiensis forest on soil properties around Tangwang river were studied. It is show that the soil properties of Betula platyphylla - Pinus koraiensis mixed forest are better than that of artificial Pinus koraiensis pure forest. These properties include pH, soil organic matter,soil nutrient and soil physical charactors. Betula platyphylla-Pinus koraeinsis mixed forest can maintain higher soil fertility and water capacity than that of artificial Pinus koreaiensis pure forest. And ability of artificial Pinus koraiensis pure forest for maintaining fertility and holding water is weaker than that of virgin Pinus koraiensis forest and Betula platyphylla-pinus koraiensis mixed forest. Study results provide a scientific way for recovery and rebuilding forest ecosystem around Tangwang river.

Abstract:Pot experiment was conducted to study effects of Cd-Cu-Ni compound pollution on six kinds of soil enzyme activities(urease,invertase,protease,phosphatase,catalase,dehydrogenase).The results showed that six kinds of soil enzyme activities had a significant(p<0.05) or very significant(p<0.01) correlation with Cd-Cu-Ni compound pollution and the influence of Cd-Cu-Ni compound pollution on six kinds of soil enzyme activities was very different.The inhibiting effect of the three heavy metals on six kinds of soil enzymes had a toxicity order form top to bottom: Cd,Cu,Ni.Under combination of Cd-Cu-Ni,Cd and Cu mainly exhibited inhibiting effect,while Ni exhibited stimulating effect mainly.The three heavy metals all exhibited stimulating effect to some extent on phosphatase.There is highly significant negative correlation between Cd-Cu-Ni compound pollution and urease as well as dehydrogenase,so it is feasible to use soil urease or dehydrogenase activities as primary biochemical index to evaluate Cd-Cu-Ni compound pollution.

Abstract:The content of soil heavy metals,Cu,Zn,Pb,Ni,Cd,Cr,Hg,As and part physical and chemical properties of the soil were determined and analyzed in the area in Liupanshui city of Guizhou province,then the appraisal for heavy metals pollution was made.The result is showed as follows: the content of Cu,Cr,Hg in the mireral slag is low,with their pollution indices lower than 1,while that of Zn,Pb,Ni,Cd,As is much higher,which single pollution index is 2.95,45.14,1.00,10.67,50.41 respectively,and the comperhensive pollution index is as high as 36.98,attributed to the string pollution resource.At the same time,the comprehensive pollution index for the soil is between 0.77 and 1.99,among which the samples with the index lower than 1 account for 50%,while proportion with the index between 1 and 2 is 50%.That result indicates that only part soil is polluted by heavy metal in low grade in the area.Therefore,proper technology of reclamation and improvement and utilizition way should be taken to ensure the soil to restore its ability to producting in argriculture in this area.

Abstract:取白洋淀底泥制成3种不同厚度的基质种植芦苇，另外设置不含底泥的麦地土壤和旱地芦苇土壤，定期对基质采样，测定底泥中重金属Cu，Cd，Pb，Zn浓度并进行比较分析。试验表明，底泥和供试麦地土壤和芦苇土壤已受到重金属Cu，Cd，Pb，Zn不同程度污染；Cd浓度均已超过全国土壤质量三级标准，分别为1．35～1．59mg／kg和1．078～1．16mg／kg，污染程度严重。其次为Pb和Zn，Cu为轻微污染。随着芦苇的生长，底泥和麦地及芦苇土壤中大部分重金属浓度呈不同程度下降趋势，表明芦苇对有害重金属有一定抗性和富集作用，旨在为底泥污染治理提供科学依据。

Abstract:通过分析不同林地类型土壤特性及林地枯落物水文特性,对缙云山4种类型(针阔混交林、常绿阔叶林、楠竹林和灌木林)林地涵养水源功能进行了研究。结果表明,灌木林表土层有机质含量为楠竹林的3.75倍,针阔混交林有机质含量为楠竹林的2.22倍,常绿阔叶林有机质含量为楠竹林的1.53倍。枯落物蓄积量为16.21~32.42t/hm2,枯落物最大持水率次序为针阔混交林>灌木林>常绿阔叶林>楠竹林,最大持水量为灌木林>针阔混交林>常绿阔叶林>楠竹林。土壤非毛管持水量由大到小依次是灌木林(66.2 mm)>针阔混交林(57.52 mm)>常绿阔叶林(47.99 mm)>楠竹林(46.98 mm)。灌木林土壤饱和蓄水量最好,为266.48 mm;针阔混交林较好,为190.4 mm;常绿阔叶林次之,为186.8 mm;楠竹林最差,为1 74.8 mm。灌木林和针阔混交林较楠竹林有更好的涵养水源功能。在今后的森林经营中,应考虑营造灌木林和混交林。

Abstract:Based on fixed observation on the sloping land in red soil region during 2002~2004,spatio-temporal dynamic change of soil water with various land use types were analyzed.The results showed that the dynamic change of soil water content was affected by precipitation and vegetation primarily,and its seasonal change had three stages: relative stabilization,consumption and supplement stage.Soil water content(0~90 cm) increased with the increase of soil depth.Based on the standard deviation and variation coefficient of soil water content,the soil profile could be divided into three layers generally: the active,the sub-active and the relatively steady layer.The variation coefficients decreased with increasing precipitation and soil depth,but increased with the increasing vegetable roots.The large differences on soil water between deep-root and shallow-root plant plots could be seen in the surface layer(0~30 cm) in rainy year, but under 30 cm depth in average year.The variation ranges of soil water in the deep-root plant plots were wider than those of shallow-root plant plots.

Abstract:在桂西北喀斯特洼地90m×40m地块范围内,用经典统计和地统计分析方法探讨了表层土壤(0~5,5~10,10~20,20~30 cm)水分的空间变异结构及其分布格局,并给出了不同置信水平和精度条件下的合理取样数。结果表明:表层土壤水分总体上具有良好的半方差结构,呈明显的斑块状分布格局。0~5 cm层具有中等的空间相关性,其余各层具有强烈的空间相关性,而且变异程度具有明显层次性;除20~30 cm层土壤水分用球状模型拟合外,其余各层均符合指数模型,且拟合效果较好。等值线图结合半方差分析可以看出,地形、微地貌、降雨和植被等是研究区土壤水分空间变异的重要影响因素。在确定合理取样数的过程中,除考虑土壤水分的统计特征外还要考虑其空间结构性。

Abstract:From May to October of 2004,based on the measurements of the diurnal and monthly transpiration rate,the evapotranspiration of a 17-year old Picea asperata Mast.and Larix gmeini Rupr mixed stand can be calculated through the transpiration area of trees in Datong County Qinghai Province.The water consumption of trees in the growing seasons can be reckoned through the evapotranspiration of plants,and the forestland evapotranspiration and water balance can be computed.The main results are as follows: Firstly,the total evapotranspiration of Picea asperata Mast.and Larix gmeini Rupr mixed stand in the growing seasons was 251.80 mm,the evapotranspiration of trees to the total field evapotranspiration and rainfall at the same period accounted for 80% and 58%.Secondly,the evapotranspiration of shrub and herb to the total field evapotranspiration accounted for 13%.Thirdly,the soil evaporation was 25.71 mm,accounting for 7% of the total evapotranspiration.

Abstract:2004年夏在山西方山北京林业大学试验基地,采用L I-1600稳态气孔仪,对不同土壤水分条件下盆栽刺槐的生理指标进行了观测。比较分析了不同水势梯度下、不同时间段刺槐蒸腾耗水速率的变化规律,结果表明:刺槐的蒸腾速率tη(μg/(s.cm2))与生理辐射强度I(μm ol/(s.m2))成幂函数关系;蒸腾速率tη(μg/s.cm2))、气孔阻力Rs/(s.cm2)和土壤体积含水量(W%)之间存在着密切的关系;蒸腾速率一般随光强的增强和土壤水分的提高而增大,刺槐蒸腾速率与土壤水分含量的相关系数平均可达0.882 5。通过研究不同土壤水分条件下刺槐蒸腾速率的差异,提出了刺槐水分利用效率的合理供水范围在10%~15%之间,为干旱半干旱地区提高林木的水分利用效率提供了理论依据。

Abstract:通过抗早节水剂FA早地龙在辣椒应用中的温室小区试验，分析抗早节水剂对土壤含水率、辣椒产量、辣椒品质的影响。试验设置5个处理区，早地龙喷施浓度分别为250和350倍液，早地龙随水浇灌量为30kg／hm^2和60kg／hm^2。结果表明：早地龙起到了蓄水保墒的作用，随着早地龙喷施浓度增加，土壤含水率提高0．38％～2．12％，土壤含水量变化幅度减小；施用早地龙的辣椒产量明显增加，产量增幅为5．0％～11．7％，同时叶面喷施FA早地龙能明显优化辣椒单果性状，平均单果质量增加7．6％～24．3％；辣椒的Vc和辣椒寨含量均随施用早地龙的浓度增大而增加，果实品质得到显著改善。早地龙对提高土壤含水率及辣椒的品质和产量起着积极作用。

Abstract:With the support of remote sensing and ecological function analysis, effects of wetlands changes on ecoenvironmental water requirement in Liaohe delta were calculated. The result showed that the change of gross ecoenvironmental water requirement did not exceed 3% that of 1988. At the same time, the changes of water requirement of various wetlands were very obviously which caused by area changes of all kinds of wetlands. The sort order of water requirement of per square kilometer is river-canal, lake-pond-reservoir, fishery land, paddy field, bulrush and supra-tidal zone. The research of this article not only can offers effective basis for calculating eco-environmental water requirement in water resource programming which are relative to protection of wetlands and adjustment of regional agricultural structure, but also can use for reference by other region.

Abstract:Using GIS and such models as dynamic degree model,spatial differences model,change of land use degree model,analyzed the land use spatio-temporal changes in Yuyang during 1988 and 2001.Moreover,we at large analysed the driving force of land use change.The conclusions were drawn as follows:(1) During 1988 and 2001,land use changed observably.Forest land,garden land,farmland,rural residential land and city and town land,traffic land increased.Meantime,unused land,grassland and waters land decreased.The synthetic dynamic degree of land use in Yuyang per year is 0.45%,which was larger than Yulin City.(2) The spatial differences of land-use change in Yuyang is obvious.(3) The change ratio of land use degree showed that in the last 13 years the land use type was during regulation.(4) In the during of land use in Yuyang,the effects of natural factors are low.Among the driving factors,the social-economic factors,such as the population,gross production value of industry,the quantity of villages and towns corporation,urbanization level,are dominant.

Abstract:Based on RS and GIS,land use changes and its driving factors in Baotou from1987 to 2002 have been analysed.The findings can be explained as following:(1) From 1987 to 2002,the areas of forestlands,grasslands and waters are reduced,whereas the areas of other land use types are enlarged.Parts of forestlands,grasslands and waters had becomed farmlands and about 31.5% of the changed grasslands transferred to unused lands.The newly-increased farmlands mainly came from grasslands and unused lands,and the former account for 36.34% while the latter 27.61%.The newly-increased lands for construction mainly came from grasslands and farmlands,and the propotion of them are 49.86% and 34.28% respectively.(2)The general quality of regional eco-environment has deteriorated from 1987 to 2002,and the land degradation,specially the lawn degeneration,and the developing the cultivated land are the main factors which the region ecological environment worsens,the ecological contribution ratio of them respectively is 51.84%(41.04%),23.63%.(3)The tendency of land use changes and its eco-environmental effects displayed spatial heterogeneity.The general quality of regional eco-environment in every district has deteriorated during the last 16 years,and the fastest is Damao County,and the slowest is Tuyou County.The degradation of meadow plays a decisive role in the deterioration of Damao's general ecological environment,and its ecological contribution rate is up to 96.61%.However,the ecological contribution ratio of the meadow degradationg,afforestation and conceding the cultivated land to forest and grass in Tuyou County are 44.23%,18.21% and 10.36% respectively.This indicates that afforestation and conceding the cultivated land to forest and grass play a certain role in the improvement of Tuyou's general ecological environment.

Abstract:Area in Qinling is the natural boundary of the Chinese between south and north. It is the important forming constituent of our country natural environment character. By the help of RS and GIS, it analyzed the quantities, inner structure, types and spatial distribution features of the dynamic changes of Qinling area in last twenty years. Furthermore,the driving forces of the LUCC were analyzed in detail. The conclusions were. The woodland, grassland and construction land area were decreased. The cultivated land, water and no-use land were increased. The woodland area change was more steady, increased only by 0. 70%, but the area of change was greater ; The cultivated land area were decreased greatly, decreased by 158 838. 02 hm^2, which changed mainly into woodland, grassland and construction and had the high quality. The construction land area was increased greatly,increased by 47.46%, which came mainly from the cultivated land. The grassland area was increased too,increased by 10.99%, which came mainly from the woodland and cultivated land;The driving forces of the LUCC in Qinling were the economic development, the pressure of the increase of population and adjustment of the macro policy.

Abstract:An analysis and study on the characteristics of cultivated land dynamic change is very important in protection,growth and utilization of cultivated land.Therefore,it tries to make an analysis on the characteristics of cultivated land dynamic change and its background characteristics as well as spatial distribution of cultivated land in Sichuan province from mid-1990s to 2000,employing GIS technology under the aid of spatial database platform.The research shows that the net decreased wet rice land are mainly turned into dry farming land,people's inhabitation and grassland and the net decreased dry farming land are turned into people's inhabitation and grassland,while most of net increased dry farming land are converted from wet rice land and forst land.The net increased cultivated land are found in slight and mild soil erosed areas as well as areas with slope degree as 4,3 and 5 and the net decreasing of cultivated land mainly happens in areas with slope degree as 1.The net decreased cultivated land are found in the plains,hills and mountains around Sichuan basin with Yaan city,Leshan city,Neijiang city and Chengdu city as the top four places,while the net increased cultivated land are often found on the the mountains of southwestern Sichuan and plateaus of northwestern Sichuan with Mianyang city,Deyang city,Aba Tibetain and Qiang Autonomous Prefecture and Liangshan Yi Autonomous Prefecture as the top four places.

Abstract:It discusses the pedodiversity and land use pattern diversity of different soil types based on a case study of Chongqing karst area. The result shows that yellow soil, limestone soil and yellow-brown soil are the major soil types in Chongqing karst area, the landscape diversity and spacial heterogeneity of different soil types are low, but the distribution of landscapes is uneven, the landscape mosaic patches present complicated geometry shape. The landscape of mountain meadow soil is dominated by forestland and grassland, the landscape of brown soil is dominated by forestland, the land use of agriculture and forestry plain a leading role in the other 9 kinds soil landscape. Owing to the difference of soil properties and soil distribution, there is a obvious difference of plantation and woodland distribution proportion in different soil types. The human activities make the number of plantation mosaic patch increase rapidly, and make the numbers of residential and industry-mine land, woodland and unused land increase also.

Abstract:Slope classification is an important precondition for slope mapping.It divides slope classification methods into three kinds: commonly subjective classification methods,critical classification methods and mode classification methods.It takes a gully and hill area of loess plateau as the test area and regards DEMs of 5 m resolution as the information source in the experiment.Slope gradient layer can be created the first.Then more works is done to make a comprehensive comparison on the characteristics,applicability and mapping effect of different classification methods.Study shows that commonly subjective classification methods are simple and flexible,but classification results have some randomicity and subjectivity,and often depend on users' professional level and experience.Critical classification methods can satisfy users' application aims well,but mapping effect are often ignored.Mode classification methods may discover the rule of real relief.The three kinds of slope classification methods have different characteristics and applicability,we should choose proper classification methods based on application aims and characteristics of slope data.The result in this research should be of significant values in directing correct and effective applications.

Abstract:The Niche-fitness theory is a further development of the classical niche theory and an extension of the related methods.It is important for human being to utilize environmental resource under sound and optimum state,to exert the most symbiotic domino effect for crop and environment and to layout or produce for industry and agriculture.Under the guidance of the theory of sustainable development for Chinese agriculture,taking Houhu Farm area in Jianghan plain as the example,and introducing the Niche-fitness Model(NFM) into the research of multi-suitability evaluation on cultivated land,this study develops quantitative analysis of niche fitness for rice,wheat,cotton and rape,which is obtained by adding weight and limiting factors models.The results indicate that the Niche-fitness value in this area is in medium and high side,the condition of zoology and environment can be able to meet basic requirement of crop in the total farm,and a part of plot should be improved in the area.At the same time,it is proved that CEC,soluble phosphorus and total nitrogen are the primary niche factors that restrict land productive potential in this area.These results can be used to supervise agricultural produce immediately,to promote reasonable utilization and scientific management of cultivated land resources.

Abstract:After the running of Three Gorges Reservoir, the riparian zone which the ecotone of water aquatic ecosystem and the terrestrial ecosystem will come into being. On the basis of investigating the type, distribution and area of riparian zone, studied the water and soil environment changed characteristic and analyzed the influence of the interactions of soil and water of riparian zone, some countermeasures such as buffers etc technologies have been proposed for the ecological environmental protection of the riparian zone.

Abstract:城郊农业生态系统是一个由社会、经济、自然等多种因素组成的复合生态经济系统,不仅提供经济产品,还以巨大的生物多样性提供多类型的生态服务功能,因此,必须合理地调整和分配土地资源,建立稳定可持续的城郊农业生态系统,实现城郊农业资源开发利用与城市生态环境建设的协调可持续发展。本文通过对兰州市城郊的农田、草地、林地和水体4种生态类型服务功能价值的分析,测算出兰州市城郊农业生态系统的年服务价值量为56.14×108元。从农业资源特征和城市生态安全要求出发,提出了适宜于兰州市城郊农业的耦合发展模式及产业化经营机制。

Abstract:利用遥感影像数据进行生态系统净初级生产力、植被覆盖度等生态参数的采集，同时间接用于土壤保持量和水土保持价值的计算，结合修改过的USLE模型，对云南省生态系统2001，2002，2003年水土保持价值进行了测算，利用NPP对估算结果进行调整．以考虑生态系统类型、结构与质量差异对水土保持价值的影响。结果表明：云南省生态系统2001，2002，2003年土壤保持量分别为131798．92，117845．5，104176．71万t，对应的价值量分别为：1933．351，1707．579，1566．783亿元。3年中林地（39．01％）、灌丛（23．02％）、草地（18．75％）3类生态系统平均土壤保持量占全省的80．77％，在水土保持中起着关键作用，因此一定要加强西部和南部的林地、灌丛和草地等生态系统的保护与管理。从水土保持价值的空间分布来看。基本保持西多东少。南多北少的格局．这与当地植被地带性分布基本一致。3年间云南省生态系统水土保持价值是逐年减少的，耕地和城市植被的水土保持价值主要受人为因素的影响，而林地、灌丛、草地的水土保持价值减少主要是由降水逐年减少造成的。

Abstract:As eco-tourism sight spot and fragile ecologic area as well, it is necessary to integrate soil and water conservation ecological tourism development, which is an important strategy for developing the local economy in Shan-Zhen-Zha region. Base on the analysis of relationship of soil/water conservation and eco-tourism development, the author suggest that, it is first step to protect soil and water resources in order to develop eco-tourism resourees and therefore to develop local socio-economies; and to support the conservation by ineome of eco-tourism development, and win the objectives of vigorously developing local economics, protecting environment, and sustainable developing of regional socio-economies.

Abstract:Ecological security is the needed state that different hierarchy or type of ecological systems to keep its normal configuration and function and gratify sustainable development for human in some period of time.It's the key part and base for agricultural sustainable development.The danger of environmental retrogression is kept on guard highly in China.The study of ecological security is becoming the major foreland and task in geography,ecology,and resource and environment science.Taking counties as basic unit,under the technique of AHP and GIS,based on the analyses of the compressive stress of the agricultural eco-security system and the set eco-security evaluation index system through pressure and quality of resource-environment and protection and renovation of resource-environment,integrative evaluating on the agricultural eco-security of counties in Dongting Lake area is made by "agricultural eco-insecurity exponent".The result indicates,agricultural eco-security of Dongting Lake area has been confronted with a series of problems and challenges,such as the descending of the accommodation function of the lake,the more and more serious of water loss and soil erosion and flood disaster,three wastes of small and medium sized cities,agriculture and heavy metals generating pollution and so on.And the regional heterogeneity of the security degree is distinct.The agricultural eco-insecurity exponent is getting smaller from near the lake to far away from it.The research achievements can be used as science-dependencies for maintaining the agricultural eco-security in Hunan province directly,and its research technique can be used for reference in regional agricultural eco-security evaluation.

Abstract:Agricultural losses result from not only the risk of hazards but also the vulnerability of flood-waterlogging disaster. It is critical to identify methods for minimizing the manifestation of flood-waterlogging flood-waterlogging condition and reducing agricultural vulnerability to flood-waterlogging. The vulnerability of land-based production systems to natural disasters is a function of the systems, underlying ecological integrity. Therefore, ecological improvement and reconstruction may reduce agricultural vulnerability to flood-waterlogging. The vulnerability of agriculture to flood-waterlogging in Hunan province is assessed based on eight factors such as precipitation, forest wreathe and income for every peasantry. The results of this assessment are used to determine optimal methods for ecological improvement and reconstruction to reduce agricultural vulnerability to flood-waterlogging.

Abstract:The basic components of the inner-gully land in Loess-Plateau-Information-Geomorphic TUPU is Loess-mao and Loess-liang, which was extracted and analyzed based on the remote sensing image. The main contents are consist of five parts, including pre-disposal of image, image recognization, model-graph operation, database management and attribute-database management. Standard parameters and model-graph of each kind of Geo-info TUPU was built through extracting the boundary of each geomorphic unit, then the unknown kind of geomorphic unit can be classified into the corresponding databases by comparing with the model-graph after the extraction of the parameters. At last the next procedures are put forward.

Abstract:On the one hand,land is the carrier of terrestrial eco-system,and it is also the base of all the human social-economic activities;on the other hand,human activities of land use must impact the eco-system,thus affect the value of eco-system service(VES for short).It studied the spatio-temporal distribution of the VES and the VES-GDP ratio in Xiaoshan district,Hangzhou.The result suggested: from 1999 to 2004,the VES presented an increasing trend,but the VES-GDP ratio presented a reversed trend at the same time;for spatial distribution,the VES-GDP ratio is higher in center area then the peripheral area's,and let the plot of which displayed like a hump.According as the spatio-temporal distribution of the VES,the whole Xiaoshan district can be divided into 4 land use areas: urban area,eastern area,southeastern area and southern area,and the suitable use of the land in each area was discussed.