Abstract:The soil structural feature was better under natural forests than that of plantation based on the analysis of soil structure in typical profiles under natural forests and plantation in upper reaches of the Yangtze River.The soil structural quality under plantation was much low than that of the natural forests after the assessment of structural quality by twelve indexes.Furthermore,the water conservation-antierodibility of the former was also low than the latter's based on the analysis and calculation of the soil water holding capacity and erosion rates under natural forests and plantation.The distributing area of plantation in upper reaches of Yangtze River are very big and facing many problems,which may relate to the soil structural quality under plantation,so the study on the protection and directive culture of the soil structural quality should be proposed.

Abstract:Based on experiments with the simulated rainfall method on soil and water loss in Huangyang small catchment,which features typical in the upper reaches of the Yangtze River,conserving efficiency of different vegetative communities were comparatively evaluated.Accordingly,optional strategy for vegetation type and distribution in the establishment of the small catchment ecosystem was formulated,and it might be a fundamental reference for more extensive applications.

Abstract:The purpose of the study is to explore the soil infiltration and runoff generation characteristics of small watershed in hilly semi-arid area of North China,Which can not only provide scientific basis for soil and water loss harness,but also for raising the rainwater use rate and rainwater use efficiency.Results showed that the runoff and sediment storage efficiency in the crops,forestry and grazing lands were increased 35.7%~91.0% and 46.2%~88.6% than that in barren land,and the effects of runoff and sediment storage were very significant.Meanwhile,Philip Infiltration theory and Stepwise Regression Analysis method were used in analyzing the infiltration and runoff results of the simulated rainfall and natural rainfall experiment,and the soil infiltration fitting equations and regression equations for the correlation between runoff amount and its correlative factors of small watershed were created.These equations showed that runoff generation coefficient had a good relationship with topographic slope,rainfall intensity,vegetation cover,soil moisture content before rainfall and soil porosity factors.

Abstract:坡面侵蚀是水流能量作用的结果．草本植被对坡面流能量的作用有重要影响．研究坡沟系统坡面草被不同盖度及空间配置下坡面流能量的变化过程与特征．对于揭示草被减蚀作用机理有重要意义。本文利用实验土槽和放水冲刷试验方法．研究了2种流量（3．2L／min和5．2L／min）．坡面5种草被盖度（0，30％，50％．70％和90％）及3种空间配置（坡上部、坡中部、坡下部）下，坡沟系统坡面径流能量的变化过程与特征。结果表明，有草断面比无草断面下的径流动能、势能普遍偏小．变化幅度也较平缓；各断面能耗时间上呈下降一稳定的变化趋势．空间上随着径流流程的增加呈显著增加趋势；坡面流能耗变化过程与径流含沙量变化过程基本一致，裸坡情况下二者关系更为密切。

Abstract:退耕还林还草是目前黄土高原整治生态环境和控制水土流失的主体政策。为使生态退耕政策得到有效落实,本文基于WIN-YIELD软件,以延安燕沟流域为例,利用19972002年延安站的逐日气象数据和燕沟流域地貌、土壤及土地利用等资料,模拟分析了不同地形高程、坡度和坡向条件下坡耕地种植不同作物可能产生的水土流失量及其地形分异特征。结果表明:地形坡度是影响径流和泥沙产生的重要因素,产生径流和泥沙的模拟值随地形坡度的增大而增大,地形坡度15°是坡耕地土壤侵蚀模数的相对质变点;地形高程和坡向对产生径流和泥沙的影响不大。

Abstract:The intermittent infiltration characteristics of sewage irrigation and surge fertigation under different fertilization rate were researched based on indoor experimental data, the mechanism of intermittent infiltration volume increased with solution concentration was analyzed. These research results have laid a foundation for further study of soil solute transfer theory and technology of sewage irrigation and surge irrigation fertilization.

Abstract:Studies on the canopy precipitation interception,litter layer water-holding capacity,soil physical property and water holding capacity of main types of artificial forests and waste grassland were made in Lianhua lake reservoir area.The results indicated that the canopy interception were 34.83%,13.05%,19.61%,the stem-flow were 6.79%,0.58%,4.01%,the throughfall were 58.37%,86.18%,77.66% of Pinus koraiensis,Larix gmelinii,weed trees,respectively.The canopy interception,stemflow and throughfall was positively correlated with precipitation amount,the experiential models between canopy interception,stemflow,throughfall and rainfall were given.The maximum water-holding capacity of the whole litter layer ranged from 12.0 to 24.0 t/hm~2,being in the declined order of Pinus koraiensis,Larix gmelinii,weed trees,waste grassland.The modified interception varied from 2.94 to 45.97 t/hm~2,in the declined order of Pinus koraiensis,Larix gmelinii,weed trees, waste grassland.The modified interception rate varied from 53.45% to 65.95%, in the declined order of Pinus koraiensis,weed trees,Larix gmelinii,and waste grassland.The maximum water storage in different forest type varied from 1 838.6~2 186.3 t/hm~2,and the order wasLarix gmelinii>weed trees>Pinus koraiensis>waste grassland;the water holding capacity of non-capillary porosity varied from 16.26~25.28 mm,being in the declined order of Larix gmelinii,Pinus koraiensis,weed trees,waste grassland.The soil infiltration rate in forest land is obviously higher than that in waste grassland.In the matter of soil layer thickness,it manifested a tendency of lowering in soil infiltration rate with the drop layer.In other words,the spatial characteristics of soil infiltration rate along the soil layer is upper layer>middle layer>lower layer. The important scientific proofs for the study of the water and soil conservation functions of the forests and further comprehensive evaluation of ecological function of forests were provided here.

Abstract:研究了次降雨过程中红壤小流域5种不同土地利用方式土壤N,P养分流失特征。结果表明,在降雨后,花生地、花-橘间作、橘园、板栗园和水田5种利用方式表层土壤N,P养分含量均有不同程度下降,其中花生地N,P含量下降最为明显,水田N,P含量降幅则最小;不同形态养分平均降幅依次为有效氮(5.49%)、有效磷(5.25%)、全氮(1.45%)、全磷(0.59%)。各样地地表径流中水溶态N,P养分含量花生地明显高于其他样地,而泥沙中N,P养分含量则以水田最高;各样地侵蚀泥沙中N,P养分有明显的富集现象,板栗园和橘园N,P养分富集率高于其他样地,水田N,P养分富集率最低。不同形态养分富集率也不同,全氮平均富集率为1.30,有效氮1.18,全磷1.11,有效磷1.38。侵蚀径流中N,P养分与表层土壤相同形态养分之间呈显著正相关。

Abstract:通过坡面人工径流小区的定位观测,对几种牧草地与农耕地和裸地的产流产沙特征以及各种牧草的全年生物量进行测定、分析与比较,结果表明:(1)牧草的覆盖度对水土流失有至关重要的影响。覆盖度较好的小区的径流深及产沙量较低,在降雨集中的季节保持较高的牧草覆盖度是减少水土流失的重要途径之一。(2)扁穗牛鞭草小区在全年和次降雨中的产流产沙量均为最少,小区全年径流深237.6 mm,为裸地的66.4%,为农耕地的58.1%;全年侵蚀模数为121.44 t/(km2.a),仅为裸地的15.7%,为农耕地的31.8%。在对7月24日次降雨的观测表明扁穗牛鞭草小区径流量为1 992 L,为裸地的57.5%,为农耕地的77.7%;产沙量为1.04 kg,为裸地的16.6%,为农耕地的50.1%。(3)在7月25日次降雨中扁穗牛鞭草小区的径流量、泥沙量及地表径流中的N,P,K含量较低,且受降雨强度的影响最小。(4)扁穗牛鞭草全年生物量为71 760 kg/hm2,明显高于其它各草种。

Abstract:于20012002年进行了“不同草带对坡耕地土壤侵蚀的影响”研究,试验设高羊茅(A)单作、高羊茅与红三叶混作(B)、非洲狗尾草与红三叶混作(C)和一个无草带种植(对照D)4个处理,坡地在13.2°14°。在每个处理上部等高种植玉米,基部种0.5 m宽的草带,底部设径流收集池,主要收集510月玉米生长期间的水土流失量。结果表明:①草带可显著减少径流量和侵蚀量,3种草带处理2年的总径流量和总侵蚀量均极显著(P<0.01)小于对照D,其中非洲狗尾草与红三叶混作的水土保持效果最好,高羊茅与红三叶混作次之,高羊茅单作为第三。②试验地水土流失主要发生在68三个月,这3个月的径流量和侵蚀量分别占总量的96.8%,99.9%,特别是6月径流量和侵蚀量分别占总量的63.2%,80.3%,草带在此期间水土保持效果最显著。所以,在坡耕地上结合农作物等高种植多年生草带是一项简单有效的水土保持技术。

Abstract:基于无石灰性潮土长期定位试验,研究长期施肥对土壤磷素状况的影响的结果表明,在无石灰性潮土上长期单施有机肥、有机—无机肥配施、氮磷钾配施能提高土壤Ca-P,Fe-P,Al-P的含量,降低O-P的含量。单施氮肥能提高土壤O-P、降低Ca-P含量。单施有机肥及其配施无机化肥比单施无机化肥有机磷增加了15.60%~11.21%,无机磷减少了11.21%~15.60%。土壤有效磷与Fe-P无相关性,与土壤全磷、无机磷、有机磷呈极显著正相关,与Ca-P,Al-P呈显著正相关,与O-P呈极显著负相关。对有效磷贡献(直接通径系数)的相对重要性依次为:O-P(72.6940)>Ca-P(69.9052)>全磷(39.6186)>有机磷(-32.8527)>无机磷(-20.9515)>Fe-P(17.2542)>Al-P(6.4832)。由逐步回归得出土壤无机磷中的O-P,Ca-P以及有机磷是土壤有效磷主要磷源。

Abstract:Cultivated layer soil samples were collected in 21 plots from main soil types in 4 cotton production areas in Xinjiang province and the soil analysis,soil adsorbing trials and pot experiments were conducted in 1996~2002 to study soil nutrient element status,the adsorbing ability of soil to nutrient elements and the bio-availability of nutrient elements by systematic approach systematically in main cotton soil types,the main results are as follows:the order of nutrient elements deficiency was N>P>Zn>K>Cu>S in Irrigated soil in Hetian area,N>P>Zn>K>Mn>Fe>Cu in Damp soil and Irrigated soil in Akesu area,N>P>Zn>Cu>Fe in Damp soil in Kashi area and N>P>Zn>S>Fe>Cu>Mn in irrigated gray desert soil in Shihezi area.

Abstract:Through the experiment of Leucaena leucocephal forest litter water-holding characteristics in Jinsha river hot and dry valley, the litter water retaining capacity was studied . The results showed that the annual litter fall was 7.03 t/hm^2 and the monthly average of litter fall was 0. 59 t/hm^2 ,the litter thickness was 2.1-4.5 cm. The maximum of monthly litter fall occurred in December. The monthly mean of water content was 25. 27%, the maximum of monthly occurred in August, water content and amount of precipitation in this area varied in the same pattern, but it expressed lag effect. Speed of water content rapidly increased within 0. 5 hour, it reached the maximum of water-holding capacity after 4- 8 hours. The water-holding capacity equal to 1.2 mm precipitation within 0. 5 hour, the forest region will not occurred surface runoff if the amount of precipitation under 11.72 mm. Saturation content rate of litter varied from 66.94%-182.86%, the maximum of water-holding content was over two times than itself weight. The relation of water content and saturation content rate varied in the same pattern in the dry season, but it was not obvious in the rainy season.

Abstract:The observations of the economic and ecological benefits of 6 types of natural vegetation management measures for three years on red soil erosion in hilly orchards showed that:(1) water-soil losses: as compared with the check of "clean tillage",the surface runoff of treatments of sod culture,paraquat,glyphosate,G-G-P(glyphosate-glyphosate-paraquat),P-P-G(paraquat-paraquat-glyphosate) could be reduced by 38.8%,42.5%,18.7%,28.7% and 37.5%,respectively,then to reduce the soil-water losses by 55.5%,51.7%,39.9%,46.8% and 50.0%,respectively,as well as to decrease the N,P,K nutrients losses by 60.3%,50.2%,37.0%,41.8% and 45.4%.(2) Weed regeneration ratios: the weed regeneration ratios with the treatments of tillage without herbicide,paraquat,glyphosate,G-G-P,P-P-G and were reduced by 55.1%,67.2%,30.3%,36.8%,51.2%,respectively,as compared with the sod culture.(3) Soil fertility: the five treatments of sod culture,paraquat,glyphosate,G-G-P and P-P-G could enhance the annual soil nutrients(N P K OM) by 7.1%,6.9%,5.3%,6.2% and 6.6%,respectively,while the tillage without herbicide reduced by 4.4 %,as compared with the original soil.(4)Yield and quality of citrus: the yields of the treatments of paraquat,glyphosate,G-G-P and P-P-G all to be increased by 7%~10%,except of the treatment of sod culture;and the contents of soluble solid,total sugar,total acidity,sugar/acid ratio and single fruit weight of citrus all to be exceeded the difference significant levels among the treatments.The treatment of paraquat showed better effect on the control of weeds,so suggested to extend it as the available natural vegetation management measure on hilly red soil citrus orchard for maintaining the water-soil and enhancing the soil fertility.

Abstract:坡地氮素淋溶是导致坡地土壤质量退化和农业非点源污染的重要原因之一。为了深入理解坡地氮素淋溶特征,采用了人工模拟降雨和天然降雨观测方法,对黄土坡地氮素淋溶特征进行了试验研究。结果表明:从坡底到坡顶土壤NO3--N含量呈不断衰减的波浪形状变化,坡底有明显NO3--N累积,其累积含量占全坡面37%~52%;坡地土壤NO3--N淋溶是二维迁移,即随着入渗水既向土体深层迁移,又向坡底迁移;降雨量分别与NO3--N淋溶深度和淋失量均呈正相关,大约每4 mm降雨量可使NO3--N下渗1 cm。本研究为建立坡地养分运移模拟模型提供了初步设想。

Abstract:Field runoff plots experiments were performed to monitor runoff,sediment yield and nitrogen loss in slope cropland of purple soil.Results showed that,Fertilization could reduce runoff and sediment yield of slope cropland.Application of manure with chemical fertilizer could reduce 68.2%,67.3% of runoff and sediment yield.Straw returned with chemical fertilizer could reduce 80.3%,92.6%.Particle nitrogen transport following runoff is the main pathway in slope cropland of purple soil because yield of particle nitrogen was above of 60.0% of total nitrogen.Balanced fertilization can reduce the nitrogen loss significantly through runoff in slope cropland.Application of N with P and K fertilizer could reduce 41.0% and 46.1% of total N compared with single N fertilizer application.Single chemical fertilizer could reduce 36.5% of total nitrogen.And manure with chemical fertilizer could reduce 69.0% of total nitrogen.Straw returned with chemical fertilizer could reduce 90.5% of total nitrogen.So that rational fertilization system could reduce the nitrogen loss from slope cropland.And straw returning has the best effect.

Abstract:针对黑土利用现状，在吉林农业大学黑土区选择不同利用方式的玉米地、休闲地、果园、草地，并在玉米区进行了不同数量的施肥。通过野外试验，采集2002年度5～10月历次自然降雨（共7次）产流及泥沙样品，同时采集降雨前后的耕层土壤样品，研究了黑土区地表径流对氮素养分特征及肥力退化的影响。结果表明：侵蚀泥沙的粒级分布特征表现为（1～0．05mm与0．05～0．01mm）2个粒级接近80％。土壤TN流失随植被覆盖度增加而减少；径流矿质氮流失随植被覆盖度增大并无减少，即植被覆盖度并不能减少土壤矿质氮流失；不同的植被类型，NH46^＋—N流失相差较大，NO3^-—N相差较小。在土壤养分含量差异不明显时．施肥量对黑土径流氮素养分流失的影响表现为泥沙TN、径流TN浓度均随氮用量增加而增加；当氮肥施用量为N2（98kg／hm^2），磷肥（44kg／hm^2）施用量为P2时，泥沙和径流氮素流失相对较小。

Abstract:Soil organic carbon and total nitrogen concentrations,soil texture,and carbon and nitrogen densities in different stages of desertification process(Potential,Light,Medium,Severe,and Most severe desertification) in Horqin sandy land were studied.The results showed that along the spectrum from potential desertification to most severe desertification,soil organic carbon and nitrogen concentrations decreased by 91.6% and 85.8%,respectively,to a depth of 100 cm,versus decreases of 95.7% for the fine particle size fractions(<0.1 mm).Carbon density decreased from 4 877.9 to 481.8(C) g/m~2 during deserification process,whereas nitrogen density decreased from 518.0 to 89.4(N) g/m~2.Regression analysis revealed significant positive relationships amongthe soil carbon concentration,soil nitrogen concentration,and soil fine particle size fractions(<0.1 mm) content for all five stages.Soil carbon and nitrogen were lost more rapidly during the initial stages of desertification than the later stages.The soil C/N ratio decreased from 9.385 to 5.541 along the desertification developing.There was a greater proportional decline in soil carbon than in nitrogen.

Abstract:In order to investigate the relationship between soil enzyme activities and soil fertility with controlled release coated urea application, soil samples from protected vegetable field grown with cucumber, tomato and pepper were taken, and soil enzyme acitivities as well as nutrient content were determined. Results showed that application of coated urea significantly improved soil organic matter, total N, alkali soluble N, nitrate, ammonium, available potash, and decreased available P content in comparison to urea. Coated urea application increased the activities of polyphenol oxidase, phosphatase, and urease, which were significantly correlated with soil nutrient factors. However, coated urea application did not increased the activities of catalse and invertase, and no significant relationship was observed between catalse and invertase and soil nutrient factors, It is concluded that it is important to consider specific crop when studying the relationship between soil enzyme activities and soil nutrient.

Abstract:Five runoff plots,which different land use patterns was built.Studying the influnces of various factors on nutrients losses.The result of the content of <0.01mm granule in 0~15 cm soil layer has observable correlation to the content of total K and Olsen-K in runoff mud and sand;The content of <0.01 mm and <0.001 mm micro aggregates in 0~15 cm soil layer has observable correlation to the content of organism,Olsen-K and total N;The degree of <0.01 mm granule reunite in the same layer has observable correlation to the content of total N and Olsen-K,and the degree of <0.001 mm granule reunite has observable correlation to the content of total P,Olsen-p and Olsen-K.

Abstract:波尔多液营养保护剂(BNPP)是一种新型的传统波尔多液(BDM)替代产品,具有杀菌谱广,无抗药性,使用、运输及存储方便等优点。本文以美国铜基杀菌剂Kocide2000(KCD)在番茄植株上的年推荐使用量为依据,模拟BNPP 10,50,100年的施用量,1次性施入盆栽番茄土壤中,研究其对土壤某些生化性质的影响,并与BDM及KCD相比较。结果表明,BDM,BNPP高浓度处理使微生物生物量碳分别降低38%,27.2%,BDM处理下pH值较对照升高0.360.46个单位,KCD,BNPP和BDM处理下的有效铁、有效锌含量减少,而有效铜含量分别提高436.4,2.624.08,8.552.06倍;施用BNPP和BDM的处理,脲酶活性分别降低2.4.5%,9.8!.95%,而KCD对脲酶的影响却不显著。3种铜制剂中BNPP对土壤某些生化性状的影响与KCD相当,而小于BDM。

Abstract:经过9150～10650mm的模拟酸雨淋溶以后，与对照相比，pH4．5的酸雨使红壤Cr累积释放量增加4．02％～88．54％，Co增加-2．35%～56．14％．Ni增加5．82％～79．53％．Cu增加-3．45％～82．23％．Cd增加4．87％～83．14％．Pb增加10．64％～99．19％；pH3．5的酸雨使Cr累积释放量增加6．72％～308．42％，Co增加14．17％～134．81％，Ni增加10．06％～140．32％，Cu增加-3．11％～258．89％．Cd增加8．44％～630．84％，Pb增加17．02％～483．15％。几种重金属元素释放对酸雨的敏感性依次是：Pb和Cd释放对酸雨较敏感．其次为Cr和Cu，而Ni和Co的释放对酸雨较不敏感。红壤中Cr，Co．Ni，Cu．Cd，Pb累积释放量差别较大，但不同土壤之间其分布表现出基本一致的特点，释放量大小依次是：Pb〉Co〉Ni〉Cu〉Cr〉Cd。红壤中Cr，Co，Ni，Cu，Cd．Pb的累积释放量（Q）随淋溶量（H）的变化符合二次模型。

Abstract:通过20012004年的田间试验研究了免耕秸秆覆盖旱作农田的土壤水分效应。结果表明,免耕秸秆覆盖对表层土壤水分含量影响较大,在作物播种期可以减少表层水分蒸发,显著增加表层土壤含水量,但随着生育进程的推进,秸秆覆盖的抑蒸效果逐渐减弱。免耕秸秆覆盖对各个时期0200 cm土壤剖面上水分总量的影响不大,但年际间变化较大。采用免耕秸秆覆盖可以提高小麦-豌豆轮作系统作物产量以及水分利用效率、促进农田生态系统的良性循环,持续提高土壤肥力。

Abstract:采用与回归模型相结合的普通克里格方法（OKR）．研究了沈阳市南郊17．6hm^2农田耕层土壤有机碳（SOC）的空间分布特征。以72个上层（0～10cm）SOC数据为辅助变量，分别以36个及24个下层（10～20cm）SOC数据为目标变量，分别进行普通克里格（OK）、协同克里格（CK）及OKR插值分析。结果表明．OKR估值的精度显著高于缺省样本条件下的OK及CK。OKR交互检验的决定系数尺。相对较高，平均误差ME的绝对值及标准化平均误差MSE接近于0、平均标准误差ASE与均方根误差RMSE较小、标准化均方根误差RMSSE接近于1．其交互检验的参数与利用全部72个样点进行的OK估值最接近。基于OKR估值的SOC空间分布图与基于全部72个样点进行的OK估值的结果具有高度的相似性。说明在目标变量数据有限的条件下，借助辅助变量，采用OKR是进行SOC分布调查的一套有效的地统计学分析方法。

Abstract:Spatial patterns of soil property at plough horizon of farm land by irrigating using Yellow river in arid desert region were studied by means of geo-statistics.The results showed that soil nutrient content of organic matter,total nitrogen,available N,available P and K could be well expressed by linear model;pH and electric conductivity was exponential and spherical model,respectively.The all of the null/sill of soil nutrient properties was equal 1.These results mean that weak spatial auto-relation existed.The spatial heterogeneity was mostly control by stochastic factors such as fertilizer application,irrigation and crop rotation et al.The spatial variability of soil pH was made of stochastic and structure factors.The stochastic and structure factors accounted for 50%,respectively.However,the structure factors of 67% and the stochastic factors of 33% constituted the spatial heterogeneity of electric conductivity.Fractal dimension and Moran's I coefficient also proved soil properties were weak spatial auto-relation and dependence.From another point of view,these results tested that the spatial variability of soil properties of shifting sand by improvement on the relative homogeneous matrix matrices were dominating made of stochastic factors.So,soil properties of cultural improvement soil in arid desert region undergone artificialness effects such as fertilizer application,irrigation and crop rotation et al.Farmers should pay more attention to these for preventing soil properties from in-homogeneity,and more resulted in lower efficiency for fertilizer.

Abstract:The Loess Plateau with degenerated soil and land use mosaics reveals a highly modified state controlled by human disturbance and topographical fluctuation.surface soil characteristics in this region are particularly sensitive to site variables and land use change.Taking Hengshan County as a case,the relationships of land types,soil properties and topography were analyzed at two different scales using CCA method.CCA showed that slope was a dominant factor influencing soil properties at both scales.Elevation and aspect was the second important features at county and catchment scale,respectively.ANOVA analysis showed that there existed significant differences in SOM,TN,TP,AN, AP and clay % between land uses.Further study using linear correlation compared the differences of effect of environmental variables on soil properties at two scales.The study indicated that soil variations are a result of comprehensive external effect of topography and land use,Also the effects exhibit different at various scales.

Abstract:According to analysis six tillage methods how to effect Dingxi semi-arid area spring wheat soil water annual change and vertical change and water use efficiency.Result shown no-tillage and traditional tillage treatments had little water storage but higher water use efficiency.No-tillage with out mulch and no-tillage mulch treatments had more water storage but lower water use efficiency.From the effects of different tillage methods to soil water storage,TW_6>TW_3>TW_1>TW_5>TW_2>TW_4,water use efficiency TW_2>TW_4>TW_1>TW_5>TW_3>TW_6.

Abstract:To decide the process and factors affected runoff and the characteristic of water erosion of large dump which produced during construction of railway engineering,study of natural rainfall for Hezhuang Dump in Beitongpu railway rebuilding project is made during raining season.The runoff and sediment yield is affected by the process of rainfall and the function of water and soil conservation measurement.The characteristic of top soil will changed by splash erosion and surface erosion,accordingly to alert the route of runoff and seepage and work to unconsistenty of soil erosion.The region of flow produce is loose embankment and the flat roof,the gully erosion chain is the main cause of the sediment yield increase.

Abstract:Based on the field experiment,the effects of cultivation technique of water collection by mulching upon the soil water content,yield of flue-cured tobacco field and WUE were studied.Research results showed that: with conventional cultivation as contract,under the treatment which planting tobacco in furrow with ridge mulched by film and furrow mulched by straw,the water content in 100 cm of soil profile and the soil moisture within different layers in different periods increased,the tobacco field evapotranspiration decreased,the yield,the ratio of the superior class leaves and the WUE of flue-cured tobacco yield increased too.The treatment was the cultivation technique of water collection fitting for the flue-cured tobacco planting in arid region.

Abstract:Based on the observation datum of typical field,experiment study on the spatial and temporal variability of infiltration have been performed on a surface irrigation field during the growing period of winter wheat,the distribution characteristic of spatial and temporal variability of infiltration parameters were described,and the correlation between different parameters were analyzed.Results showed that the spatial variability of soil infiltration parameters continually decreased during the growing period of winter wheat,the temporal variability gradually weakened and became stable.The difference of infiltration capacity was not obvious after pre-irrigation,so the effect of temporal variability can be neglected in the field irrigation design and management,or surface irrigation simulation.Because of the strong correlation and similar spatial and temporal variability between f_0 and Z_(180),the distribution characteristic of spatial and temporal variability of f_0 can be used to describe the soil infiltration characteristic and weigh the soil infiltration capacity.

Abstract:To make clear the groundwater of the main replenishment resources and that rely for existence of desert plant;According to the data analysis of the groundwater experiment field in Yulin,and mechanism analysis of the condensation in the desert pool of the North Area of Shaanxi.The characteristic of the precipitation intercepted by groundwater are studied;and the formula of the calculation condensation is to deduce out,and pass to experiment to proceeds to that formula the verification;it is to the leading meaning that development of groundwater and to have got the importance with the water and soil conservation in that regions.

Abstract:根据延安地区的水土流失特点，在对全区已建淤地坝进行综合调查分析的基础上。从侵蚀控制和拦泥减沙需要的两个方面对淤地坝建设规模进行了分析，依此确定延安地区黄土高原淤地坝的建设规模，淤地坝建坝总数27705座。其中骨干坝2847座，中型坝6804座，小型坝18054座，为延安地区的淤地坝建设提供理论依据。

Abstract:Much attention has been paid to river health assessment and restoration.Ecological degradation of Yellow river has been serious,thus the study on its health assessment and restoration is of great significance in theory and practice.Based on the analysis of Yellow river health connotation, the health assessment system of Yellow river,including the mainstream and branch health,river headstream,upstream,middle stream,downstream and river mouth health,watershed socio-economy and natural system health,are framed,and the performance indicator system of Yellow river health,consisting of five components as water quality,water quantity,aquatic life,physical form and riparian zone,is established.Moreover,the restoration activities of macro,middle and micro level of Yellow river are put forward,and the priority areas of restoration are identified.

Abstract:南水北调西线一期工程从雅砻江支流鲜水河的达曲、泥曲和大渡河支流的色曲、杜柯河、玛柯河和阿柯河等6条河流通过“六坝七洞一渠”,将40亿m3/a水调到黄河的支流贾曲。这一水量约占引水坝址河川径流的65%~70%,剩余30%~35%的水量能否满足河道内的生态需水,需要进一步研究。本文通过分析该调水区河道内的生态需水主要是满足水生生物栖息地的需水要求,讨论了水生生物产量与水体水量之间的关系,利用河道内径流50%保证率的河道径流的30%作为最小生态径流量的方法,估算了达曲、泥曲、绰斯甲河、足木足河的水文站断面的最小生态径流量,并利用Tennant方法对估算结果进行了评价。结果表明:4~9月采用最小生态径流量可以使河道的流量状态处于中等水平,10~3月若河道内流淌着最小生态径流,可以使河道内水生生物及河道的正常功能处于非常好的状态,只要工程建成后采用计算的最小生态径流为河道内下泄流量,就可以保证同时满足调水河流的资源水和生态水。

Abstract:The definition of ecological water requirement is proposed from different point of view based on former research in this study. An integrated classification system for ecological water demand is suggested according to different criterions. Then give methods for calculating inner-river and off-stream ecological water requirement. After that, take Yanan city for example to calculate two kinds of ecological water requirement in the year of 2000.

Abstract:The landscape pattern and its dynamical change of the 13 provinces in the North China during 1989~1999 have been analyzed in the paper by using RS,GIS and FRAGSTATS,which are based on the 1 km NDVI images in 1989 and 1999.The results show that grasslands,unable land and forests are the main landscape types in the research areas.During 1989~1999,the landscape pattern become diversification and evenness.As a whole,the fragmentation of arable land,forests and cities and residential areas are bigger than other landscape types.Human seriously disturbs forests,grasslands and water areas.Grasslands become more and more fragmentized,the fragmentation of grassland increases from 19.23% to 41.69%.The transition between the landscape types is mainly the changes between forests,grasslands and arable land and grasslands changing to unable land.The ecological environment in the area is obviously degenerated due to the human activities.

Abstract:土地利用／土地覆被变化不仅改变了地表景观结构及其物质循环和能量流动，而且对区域生物多样性和重要生态过程有着极其深刻的影响。通过对怒江流域1985，1995，2000年3个时期的土地利用／覆被空间数据的分析计算，得出近15年来，各土地覆被类型的动态变化信息，并借助景观生态学中的景观格局变化分析模型进一步研究了流域土地覆被变化产生的生态环境效应。研究表明：1985～2000年怒江流域各土地利用类型及景观格局指数均发生了重要变化。土地利用变化表现出城乡居民工矿用地、耕地、草地明显增加，而林地和未利用地呈减少趋势，反映出流域城镇化进程的加快和生态环境恶化的趋势；景观总体上表现异质性在减小，斑块类型趋于均匀分布的趋势，景观稳定性在降低。

Abstract:Based on the statistics data and groundwater information,we analyzed the land use change and its effect on groundwater,by geographic information systems(GIS) and the Cobb-Douglass production function.As a typical agricultural county in the salinity transforming region,the results showed that the speed of LUC was slow and the farm lands,which changed into rural resident lands and town lands,was the key change type of land use transfer. At the same time,the multiple cropping index,irrigation area,grain yield and the rate of irrigation had been improved increasingly.The high dependency of crop and vegetable yield on irrigation was the key cause of the change of groundwater embedded depth.The exploitation areas of shallow and deep groundwater were respectively the balance area and the moderate overdrawn area by the dividing criterion of groundwater overdrawn area.It is necessary to adjust the structure of crop production,reduce properly the intensity of land use,develop the saving water agriculture in order to realize the regional sustainable use and water in the salinity transforming region.

Abstract:Global-warming is one of the important environmental problems.Previous studies often interpreted the influence of land-use change to climate by studying the change of the earth surface's parameters.But the increase of greenhouse-gases,an important factor which influence the climate is neglected.By analyzing the data of fluxes of greenhouse-gases from various land-use types in Sanjiang plain,we compare the influence of different landuse to climate.The result expresses that the greenhouse effect of woodland>Calamagrostis angustifolia>Carex lasiocarpa>Carex pseudo-curaica>paddyfield>soybean are different.The magnitude of the influence can be soybean>Calamagrostis angustifolia>Carex lasiocarpa>woodland>paddyfield>Carex pseudo-curaica.So,if the wetlands will be changed into farm land,the rice paddy is more suitable than dry land.In the past years,for the land-use change in Sanjiang plain,total quantity of different greenhouse-gases has changed.Among them,the amount of CH_4 decreased,but that of CO_2,N_2O increased.The increase of GWP which is resulted by land-use change is one of important factors of region climate warming.

Abstract:Remote-sensing identification combined with the site visit was applied to find out the land use situation since 1950 in Hongqi gully watershed,and an analysis of the land use succession as well as land conversion situation was made,showing that land use was closely associated with the watershed treatment,construction of basic farming land and human disturbance.Land conversion was related to the proportion of forestation and fruit trees,and the proportion of land conversion was related to the development of basic farming land,especially proportion of dam field.

Abstract:Based on the investigating undergrowth vegetation in the forests with different densities in semi-arid region on the loess plateaus,the niche of undergrowth vegetation are described and analyzed,with different densities as the resource state and with the important value as the resource state descriptor of the niche.The results indicate that most of undergrowth vegetation have lower niche breadth values,but Heteropasppus altaicus and Arremisia sacrorum have higher niche breadth values,59.7% of the herbage species have niche overlaps,but which are lower.All the above reveal that the bad condition of undergrowth vegetations.

Abstract:The changing characteristics of species diversity of Caragana microphylla pasture during the process of sandy desertification in Keerqin Sandy Land were studied. The invasion and disappearance of plant species, the change of dominance and life form structure, and niche breadth of dominant populations were also analyzed, The species diversity indexes analysis showed that desertification was a process of bio-diversity loss. And most of original species were wiped out in this process especially from fixed sand dune to semi-fixed sand dune stage. Change in life-form spectra indicated that Hermicryptophytes were severe affected by desertification. The drift of niche breadths of 17 main plant populations in the process of desertification was measured using the formulas described by Levins. The results showed that the niche breadths of most original species decreased and those of psammophytic species increased accordingly in the process of desertification.

Abstract:Geo-STATer is a computer program for semivariogram analyst,geostatistical prediction and simulation.In addition to classical statistics,it provides basic geostatistical functions,including semivariogram analysis,cross-semivariogram analysis,fitting the theoretical semivariogram or cross-semivariogram model,ordinary kriging interpolation,cokriging interpolation and inverse distance weighted method interpolation.The paper presented the system design,function and realization of this software.Taking soil data as an example,the running results of Geo-STATer were compared with those using other two geostatistical software,such as GS~ and Geostatistical Analyst for ArcGIS.The results showed that Geo-STATer had acceptable accuracy and considerable efficiency.It can be not only used to study the spatial variability of soil properties,but also integrated with other professional models for developing the precise fertilization management system.

Abstract:表面电荷性质对于水体中粘性泥沙颗粒的稳定和聚沉起重要作用，因此本试验测定3种紫色土胶体的表面电荷性质，并讨论其随环境条件改变而变化对紫色土粘粒悬浮液稳定性的影响。结果表明：（1）3种紫色土胶体在2：1型电解质中的表面电位分别约-0．14～-0．192 V．1：1型电解质中约为其2倍，在2种离子体系中的絮凝值分别为0．72～1．12mol／m^3和11．7～17．8mol／m^3，胶体稳定性随其表面电位增加而增强；（2）1：1型电解质中粘粒悬浮液完全沉降时间分别达到40．6～47．0h，比在2：1型电解质中长12．4～14．6h，电解质浓度增加，粘粒悬浮液完全沉降时间下降．稳定性减弱。pH对完全沉降时间影响强烈，当pH=5时，2种电解质体系中的粘粒悬浮液完全沉降时间减少近1／2；pH=3时，60min左右悬浮液已经沉降完全。3种紫色土悬浮液稳定性是酸性紫色土〈中性紫色土〈石灰性紫色土。

Abstract:在不同CO2浓度下，测定了湿地松上年生针叶和当年生针叶净光合速率（Pn）、蒸腾速率（Tr）、胞间CO2浓度（Ci）、气孔导度（Cs）和叶面饱和水汽压亏缺（Vpdl）随光照强度的变化。结果表明；Ci和Vpdl随光照强度增强而减小；G5，Pn和Tr均随光照强度增强而增大．在达到光饱和点后G5和Pn随光照强度增强而逐渐减小；WUE随光照强度增强呈先增大，达到最大值后又逐渐减小。Ci，vpdl随CO2浓度升高而增大；Gs和Tr随CO2浓度升高而减小；Pn和WUE在CO2浓度为400～1200μmol／mol时随CO2浓度升高而增大，当CO2浓度升高至1600μmol／mol时．Pn和WUE减小；同时．随着CO2浓度升高，上年生针叶光饱和点提高。

Abstract:The experimental study was under the condition oI glasshouse on the aphcation of FA Handilong. Different use way and different use quantity were made in this research. The effects on soil moisture, vegetal rate, output and the quality of melon were studied. The data shows that FA Handilong could effectively improve the soil moisture, advance the growth of melon, increase the output and improve the quality of the melon. According the research this paper provides the reasonable use way and use quantity.

Abstract:Field experiment has been conducted to illuminate regulating effects of irrigation and nitrogen on paste traits of starch of two spike-type wheat cultivars.The results indicated that the correlation coefficients were highest between PV and other parameters,especially the correlation coefficients were more than 0.93 between PV and TV,FV,which showed that PV was a important index in weighing paste traits of starch.By comparison of two cultivars,BD of Yumai 49 was lower than that of Yumai66,the other parameters of Yumai49 were higher,which suggested that paste traits of starch of Yumai 49 was better.Strategy of irrigation and nitrogen had a strong effect on paste properties of starch of two spike-type wheat cultivars,and variation coefficients of Yumai 49 were higher,which was good to regulate to improve starch quality.In general,treatment with 300 kg/hm~2 N was better,irrigation treatment with one application was proper in management of water and nitrogen for Yumai66,but treatment with 150 kg/hm~2 N was best,irrigation treatment with two applications was effective for Yumai 49.Experiment also suggested that there was interaction between irrigation and nitrogen,paste traits of starch can be improved by applied nitrogen according to irrigation,the difference was significant between two spike-type wheat cultivars.

Abstract:By much field investigation and research, we find there are many different types of cracks and fissures in loess and they form cracks and fissures network. These cracks and fissures are structure planes of dividing loess, preponderance planes of tunnel erosion of soil, control planes of arising geological hazards and are seeping channels and storing room of groundwater. So to study on them is very important and useful. The cracks and fissures have been classified according to their size, character of mechanics, cause and time of formation. Affected by neotectonics, landform, groundwater and climate in Loess Plateau of China and by character, structure, component, granularity, age and depth of loess, characteristics and distribution of cracks and fissures of loess in Loess Plateau are different and are summed up here. We consider the commonly vertical joints in loess as to be growing up from some of the different original and secondary vertical cracks during sedimentation of loess.

Abstract:Soil contamination with copper consist mainly ot natural source and human activities source. The specific adsorption of copper to soil organic matter, Fe/Al oxide is the main factor affecting copper bioavailability in soil. Nowadays, the phytoremediation materials such as Elsholtzia splendens, Cornrnelina communis, Rumex acetosa Linn, and Elsholtzia argyi have been investigated widely in China for the phytoremediation of copper contaminated soil. Solution culture and pot experiment, field experiment have been done to investigate the physiological and biochemical response to copper toxicity, and the phytoremediation of copper from the contaminated soil by E. splendens. E. argyi also show the potential for the phytoremediation of heavy metal polluted soil. The disposal of remedial materials after removal of their heavy metals from contaminated soil for the fully utilization of phytoremediated plant materials is particularly important to implementate this innovative environmental biotechnology.