Abstract:我国北方传统耕作模式的犁耕、耙磨及磨平整地措施对农田近地表风沙活动影响显著。通过对春季半干旱沙区农田风沙活动的观测,本文对犁耕、耙磨磨平两种处理下近地表0~60 cm内输沙率和风沙流结构随田块长度的变化规律进行了研究。结果表明,耙磨磨平处理破坏了犁耕在农田地表形成的非可蚀性土块结构,使近地表0~60 cm内输沙率增大,在强沙尘事件中增加幅度可达数10倍。犁耕地表上输沙率随田块长度的增加呈指数关系递增,而耙磨磨平后风沙流发育的饱和路径长度减小,在强沙尘事件中近地表输沙率随田块长度的增加而递减。此外,上风向处犁耕地表低层输沙比例(Q0-10/Q0-60)小于耙磨磨平地表,且随田块长度的增加逐渐增大,而耙磨磨平后风沙流结构随田块长度的变化不大。

Abstract:在山东省夏津县黄河故道冲积沙地建立土壤风蚀试验区,采用标尺法对3种网格的农田防护林和对照地的土壤风蚀量进行观测,测定结果表明:农田防护林网可明显减少风蚀损失,其中,130m×300m林网相对于对照减少土壤风蚀量81%,260m×300m林网相对于对照减少78%,300m×400m林网相对于对照减少75%,即随着网格面积的增加对风蚀量的影响越来越小。同时,土壤风蚀程度与测定期间日平均风速>4 m/s的出现频率有密切关系,土壤风蚀量与风速之间的最佳拟合关系为幂函数关系,二者之间呈正相关关系,相关系数在0.95以上。黄河故道冲积沙地农田防护林网对5.0~5.9 m/s范围内的风速引起的土壤风蚀防治效果最好。

Abstract:Effects of soil surface characteristics and gradient on runoff and sediment production were analyzed by comparable experiments. It showed that soil crust and gradient both have effects on runoff by reducing infiltration; the contribution of soil crust is decreasing with gradient, whereas the contribution of gradient is increasing with gradient. On each gradient, the effects of soil crust are decreasing with rainfall time. Once soil crust formed, the increment of erosive force is larger than that of anti-erosive force, and so induces the improvement of sediment yield. It is still high of runoff and sediment yield for broken crust soil, and so it is impossible to eliminate the effects of soil crust completely only disturbing the soil surface.

Abstract:风蚀是我国干旱、半干旱地区土壤退化的主要影响因素。本实验采用室内风洞实验,研究了不同PAM处理对土壤的风蚀控制效果。实验土壤分别是黏粒含量为28.0%的壤土和黏粒含量为15.2%的砂壤土,实验条件为固定风速14 m/s、固定吹角5°。研究表明,对土壤表层覆盖PAM可以增加土壤的抗风蚀能力,有效地减少土壤风蚀,增加PAM使用量可以进一步增加土壤的抗风蚀能力,即4 g/m2PAM用量的效果要好于2 g/m2PAM的用量;前期累积在土壤中的PAM不能明显增加土壤抗风蚀的能力;在水分和PAM的共同作用下,黏粒含量高的土壤的抗风蚀能力要强于黏粒含量低的土壤。

Abstract:In this paper,soil water erosion of lucerne-spring wheat rotation soil in Dingxi under has been studied.The results showed that Pounding time of lucerne field with till(T1) is the longest.Runoff time of lucerne field with no till(T2) was the longest,which was significantly higher than three treatments.In the whole process of rainfall simulation,the runoff velocity of no till was lower than that of tilled.In four treatments,the runoff velocity of lucerne field with no till(T2) was the lowest,but between two tilled treatments had not significant difference.The infiltration velocity of lucerne field with no till(T2) was higher than that of other three treatments.Straw covering could decreased cumulated runoff and sediment and increased infiltration in the same time.In the different treatments,the result of resist water erosion of lucerne field with no till(T2) and 100% straw cover was obvious.

Abstract:当前核素示踪技术和侵蚀产沙模型联合应用于侵蚀空间分异规律研究甚少且主要集中在流域尺度上。本研究利用WEPP模型和137Cs核素示踪技术估算了川中丘陵区简阳县贾家村附近两块坡耕地的侵蚀速率,进而对两种方法估算的侵蚀速率在坡面上的空间分布规律进行了分析。研究表明用137Cs核素示踪法测算的两块坡耕地的侵蚀速率随坡长增加而呈波动变化特征,用WEPP模型估算的坡耕地和坡耕地的土壤侵蚀速率随坡长增加而增大。坡耕地I顶部极高的137Cs计算的侵蚀速率和极低的WEPP模型计算的侵蚀速率表明人工刨地耕作逐渐把该坡耕地顶部的耕作土迁移至下部并将坡顶变成该坡耕地内最贫瘠的部分。用WEPP模型模拟的侵蚀速率与用137Cs计算的侵蚀速率在量上和空间分布上都有较大的不同,这说明在川中丘陵区用WEPP模型来估算传统耕作方式下坡耕地的侵蚀速率存在一定的局限性。

Abstract:The characteristics of soil anti-scourability and its primary influence factor in different land use types of Purple soil hilly region were studied.(1)The results showed that the sediment concentration had a decreasing trend during the process of scouring,but the traditional farmland's had a increasing trend from 7 to 10 minute.The sediment concentration were traditional farmland(0.81 g/L)>tree-crop intercropping land(0.73 g/L)> orchard(0.69 g/L)>bamboo forest land(0.58 g/L);(2)During the scouring process,the index of soil anti-scourability increased gradually along with the time,and the order of soil anti-scourability is that the maximal is bamboo forest land,orchard and tree-crop intercropping land were secondary,and the minimal is traditional farmland;(3)The index of soil anti-scourability were bamboo forest land(1.37 min/g)> orchard(0.99 min/g)> tree-crop intercropping land(0.92 min/g)> traditional farmland(0.70 min/g),and the index of soil anti-scourability of bamboo forest land,orchard and tree-crop intercropping land is respective 1.96,1.41 and 1.31 times as traditional farmland;(4)Root system had obvious enhancement effects on Purple soil antiscourability,and the intensified values of soil anti-scourability by root system were bamboo forest land> orchard> tree-crop intercropping land> traditional farmland.

Abstract:Soil erosion and agricultural non-point source pollution is one of the key eco-environment problems for uplands agriculture in the Three Gorges Region.Biological methods,characterized by little cost,easy for operation,and effective quickly,should be suggested to alleviate the eco-environment problem.Substitute crop of perennial alfalfa and Contour Hedgerow Technology were tested in this research on the effect of reducing soil,nitrogen and phosphorus losses from upland of purple soil.Five treatment plots were set up,and the runoff,sediment,nitrogen and phosphorus losses through sediment by each rainfall event were monitored for each plot from January 19,2002 to November 27,2004.The treatments are perennial alfalfa,ryegrass rotates with soybean,wheat rotates with peanut and Toona sinensis Roem contour hedgerow,wheat rotates with peanut and alfalfa contour hedgerow,and wheat rotates with peanut.The research showed that annually 68.00%~81.80% of the regional precipitation distributed from April to September,and most of the soil erosion,nitrogen and phosphorus losses occured at this period.Substitute perennial alfalfa and contour hedgerow technology are effective in reducing soil erosion and sedimentary nitrogen and phosphorus losses.

Abstract:This study was conducted in Shanghai to investigate the ecological slope protection techniques of rivers. In Spring of 2004, the demonstration projects of ecological riverbank protection were implemented in Airport Town, Pudong New District, including soil bioengineering, all-series vegetated protection, and combined biostabilization. In order to assess the soil and water conservation benefit of the protection projects, continuous ecological monitoring has been conducted from 2004 to 2006 after the projects were finished. The results indicated that the pioneer species such as Salisc suchowensis, Salisc babylonica, Zoysia sinica , are growing very well with strong root system and flourished branches, which help control soil erosion effectively and make stable habitats for other plants. In recent three years, the native plants have covered the whole ecological riverbanks and get significant soil and water conservation effects. The results of the soil strength testing indicated that soil anti-erodibility of ecoriverbanks is going up. The surface soil strength of all-series vegetated protection, live stakes and live fascines are increasing sharply. For brush mattress, the subsurface soil strength with a mean deepness of 15 cm is much higher than other eco-riverbanks and the un-covered control slopes. Soil erosion never occurred distinctly after the riverbank protecting projects were finished.

Abstract:大气核爆产物137Cs能够强烈地被土壤颗粒所吸附,是一种示踪土壤运移的良好示踪剂。通过对紫色丘陵区响水滩小流域不同地貌部位和不同土地利用类型下土壤剖面中137Cs含量的测定与分析,计算了流域各地貌部位、土地利用类型的侵蚀强度。研究得出该流域137Cs含量的背景值是1870 Bq/m2;流域内坡耕地、林地的年均侵蚀强度分别是4468 t/(km2.a)和1759 t/(km2.a);丘顶、丘坡和鞍部的年平均侵蚀强度分别是2125,4676 t/(km2.a)和3625 t/(km2.a),槽土和水田则是沉积区。分析结果表明地貌部位和土地利用类型对土壤侵蚀影响巨大,坡耕地是该小流域泥沙的主要来源。

Abstract:Process of watershed topography variation by rain erosion was studied with indoor simulating experiment. The result shows that watershed surface area, channel projected area and watershed volume per precipitation varies regularly. Channel projected area and watershed volume increase firstly, and decrease after reached definite degree. But surface area increases firstly, then fluctuant state after reaches definite degree.

Abstract:It studied the relationship between the dam and reservoir control area ratio to the total area,the dam and reservoir capacity unit area(DRCA),the critical DRCA and sediment reduction effect in the northwest of Shanxi and north of Shaanxi in the Hekouzhen-Longmen area of middle reaches of the Yellow River.The results show that:(1) In the northwest of Shanxi,without the dam and reservoir engineering,the control measure of the slopeland accounted for 14% in sediment reduction.The sediment reduction effect increases with the increase of the dam and reservoir control area,reservoir capacity and DRCA: the increase of 100 km2 in dam and reservoir control area can increase 2% in sediment reduction effect;the increase of 4 000 000 m3 in the reservoir capacity can increase 1%;and the increase of 10 000 m3/km2 in the DRCA can increase 10%.(2)In the north of Shaanxi,the sediment reduction is mainly attributed to the dam and reservoir engineering,the DRCA of 50 000 m3/km2 can increase 10% in trap efficiency;the DRCA should be more than 60 000 m3/km2 if the sediment reduction effect of the comprehensive watershed control of soil and water conservation achieves 20%.(3)In the areas with high and coarse sediment yield of middle reaches of Yellow River,if the sediment reduction effect reaches 40%,the DRCA should excess 160 000 m3/km2.

Abstract:Static absorption and soil column leaching methods were used to study ammonia volatilization and N leaching characteristics from six controlled/slow-release fertilizers. The results showed that all the controlled/ slow-release fertilizers decreased ammonia volatilization and N leaching in varying degrees. Total ammonia volatilization of six controlled-release fertilizers decreased by 16.62%, 23. 78%, 32. 15%, 0. 11%, 16.59% and 37.78% than common urea respectively,and N leaching amount of the fertilizers decreased by 15.84%, 38.27%, 68. 87%, 46.17%, 52.51% and 62.01% than common urea respectively. The results also indicated that ammonia volatilization from controlled/slow-release fertilizers was closely related to soil urease activity and pH value.

Abstract:With soil-resin-core equipment, correlation between sheep manure application and nitrate leaching amount under grassland-farming system in three gorges region was studied. Results showed that there had nitrate accumulation of organic fertilizer in soil. Nitrate accumulation and total soil nitrogen content increased with increasing manure application. Nitrate content in soil changed seasonally because of changing precipitation, temperature and grass growth and highest content was found in January. Total soil nitrogen content and nitrate content significantly influenced nitrate leaching amount from 20 cm depth soil, they had significant positive correlation. Manure application significantly increased grass yields while surplus application decreased yields and increased nitrate leaching possibility. Under certain grass yields, carrying capacity of sheep manure by pasture was higher than the manure produced from sheep breed on certain area of pasture. With manure returned to pasture, it is feasible to develop confinement rearing in three gorges region based on resources and environment.

Abstract:Effects of applying different nitrogen fertilizer on yield,quality and nitrate leaching in soil layer were studied during the cucumber growth period in greenhouse.The result showed that N uptake was not significant difference between conventional nitrogen treatment and optimum treatment.RE,PE and AE of conventional nitrogen treatment were lower than optimum treatment and 91.65% of applied N was lost by the kind of ways.Nitrate leaching loss was the dominant factor.It is also found that nitrogen applying with conventional treatment inhibited the absorption of other nutrients.In the term of yield and quality of cucumber,optimum treatment(N2) were not different from the conventional fertilizer treatment,but it could increase Vc content and active acidity(pH).

Abstract:In order to understand dynamics of soil water-stable aggregates along chronosequences and relationship with soil physico-chemical properties on abandoned arable land in eroded hilly loess plateau,11 arable old land with different ages after being abandoned in Zhifanggou catchment were studied systematically through the approach of substituting the temporal serial with spatial serial.In addition,the correlation between soil water-stable aggregates and physico-chemical properties were examined.The results showed that the contents of soil water-stable aggregates increased promptly in early abandoned stage,and increased slowly with the extension of being abandoned,then kept a relatively stable content in the follow years.The contents increased by the percentage of 253.45% in the first 10 years of being abandoned,but by only of 16.42% in the follow 40 years.The significant correlations were observed between >0.25 mm aggregate and soil organic carbon,total nitrogen,available P,CaCO3,CEC and microbial biomass C,N,P,but not with available K.It is necessary to close and manage hillsides as well as keep soil organic carbon in a good balance in order to improve soil structure on abandoned arable land in eroded hilly loess plateau.

Abstract:采用PAM、β-环糊精、沃特保水剂、腐殖酸等4种土壤结构改良剂，通过室内土柱培养，以研究其对风沙土有效的改良效果，并探讨其作用机理和合理的施用浓度。结果表明，4种改良剂均可促进〉0．25mm水稳性团聚体的形成，在低浓度（0．05％～0．1％）下其趋势为：沃特保水剂〉β-环糊精〉PAM〉腐殖酸，在高浓度（0．2％～0．4％）下趋势为：PAM〉β-环糊精〉沃特保水剂〉腐殖酸。4种改良剂在浓度为0．05％～0．4％时，均可有效地降低风沙土团聚体的分形维数，改善风沙土结构，尤其沃特保水剂改良效果最明显。在低浓度下，4种改良剂均可有效地降低土壤容重。回归分析和方差分析表明，沃特保水剂主要作用于5～1mm粒径的团聚体，其适宜浓度为0．05％左右。

Abstract:It sampl the 0~100 cm section of windblown soil and new silt land and silted tilth in the flood irrigation area of Gongwusu,and mensurated the soil nutrient content and grain size constitute,in order to analyze distribution characteristic of nutrient and grain size of the soil after silting up using the flood with high sand.As a result,available P content in the new silt land is 4.2 times than the original shape wind-blown soil,the same available K is 2.5 times,alkali-hydrolysable N is 2.4 times,whole N is 2.7 times,whole P is 1.3 times,organic matter is 3.3 times,and available K content comes to very high grade in the whole country soil census for the second time nutrient standard,available P comes to abundant grade.Through Leading the flood with high sand into the basin of the desert for silting up many times,when alluvium thickness exceed plow,the desert can becomes the high quantity farmland.It is a very valid approach to use the flood with high sand controlling sand and silting land for reducing the yellow river bed silted and controlling desert and developing farmland.

Abstract:By combining conventional statistics and and GIS spatial analysis, this paper quantitatively explored the main related factors for spatial distribution of soil organic matter, total N, available P and available K in Dehui County, a typical agricultural county in Northeast Plain. Results showed that, there were no significant differences for soil nutrients under different elevation group. There exist significant differences between slope degrees for soil organic matter and total N. Lower values of soil organic matter and total N concentrations were associated with larger gradient because of soil erosion. Slope factor have no significant effects on soil available P and available K. Soil type and land use type affected the spatial variability of soil nutrients obviously. Spatial distribution map of soil nutrients revealed that, after being divided into two parts along the Yinma River, for soil organic matter, total N and available K, samples in the eastern part have statistically lower values than those in the western part. However, there was no obvious changing trend for available P.

Abstract:Nutrients sourced vegetable greenhouse soil from Linfen city in Shanxi province were investigated.The nutrient indexes included soil organic matter,available nitrogen,NO-3-N,readily available P,available K and the changes of soil electrical conductivity,dissolvable salt and pH.The results showed that compared with the open field soil the greenhouse soil electrical conductivity and the salt content increased and pH decreased gradually.The content of soil salt in greenhouse of planting 8 a had accumulated to the cucumber's critical point of which obstacles the growth.The soil nutrients accumulated in distinct degrees,especially the readily available P and NO-3-N accumulated heavy.The main reasons caused the accumulation of soil salt and nutrients are the special environment condition of greenhouse and the surfeit use of fertilizer.

Abstract:采用地统计学的变异函数分析方法，定量研究了14年生水曲柳人工林表层土壤（0～10cm）养分的空间异质性特征。结果表明：（1）土壤有效磷、全钾和速效钾变异函数曲线的理论模型符合指数模型，土壤pH值符合球状模型，土壤全氮、水解氮和全磷的理论模型符合指数模型或球状模型；（2）土壤养分各项指标的空间变异主要是由结构性因素引起，且空间自相关程度均属中等以上（空间结构比均在25％以上）；（3）土壤pH值的空间自相关范围最大（2．27～4．46m），土壤全磷的自相关范围（0.73～0．97m）小于全钾和全氮（分别为1．02～1．05m和0．90～1．18m），土壤有效磷的自相关范围（0.90～1．20m）小于速效钾（0.95～2．86m）和水解氮（1．41～4．25m），速效养分的自相关范围均大于或近似等于相应养分的全量养分。（4）土壤pH值、氮、磷和钾素的空间格局明显，土壤pH值、全氮、水解氮、全磷、有效磷、全钾、速效钾的分数维分别为1．789～1．862，1．217～1．952，1．838～1．927．1．878～1．935，1．899～1．944，1．936～1．965，1．907～1．963。

Abstract:基于15年石灰性潮土长期定位施肥试验，用水浸提法、Olsen法、Mehlich3法研究土壤磷素有效性。结果表明：长期不施磷的处理，土壤磷素有效性常年维持在本底的极低水平；施磷均能增加水溶性磷、Olsen—P、Mehlich3-P的含量，但磷钾配施及大量施用有机肥的效果最明显，其次是有机肥与NPK配施，只施无机肥（NPK，NP）增加的幅度相对较小；然而，在当前的施磷水平下，土壤“不缺磷”，但不能建立较大的有效磷库，并且以Olsen—P、Mehlich3-P的临界点为标准，土壤磷素流失的风险不大；水溶性磷、Olsen—P、Mehlich3-P的比值约为1：10：25，用幂函数、指数方程、对数方程能较好地模拟3种浸提磷之间的转化关系；水溶性磷、Olsen—P、Mehlich3-P与作物地上部吸磷量均达到极显著正相关，相关系数分别为0．563，0．854和0．930，表明用水浸提法、Olsen法、Mehlich3法研究长期定位试验中土壤磷素的有效性均可行。

Abstract:The changes of soil organic carbon storage in different land use systems are analyzed here.The results are as follows:(1) Among the different land use systems,the different is clear in the amount of soil organic carbon,and the general trend is,economic forest(Castanea mollissima Blume)> soil and water conservation forests> farmland.(2) Among the various land use systems,the content of soil organic carbon(SOC) and soil carbon density decreased with the increase of soil depth,but the extent of decreasing is different due to different land use systems.The change of the amount of soil organic carbon in farmland soil depth is not obvious.(3) The total carbon storage is 41 573.67 t in the study area,and the contribution rate of economic forest of Castanea mollissima Blume is 46.02%,highest among all land use systems;the soil and water conservation forests soil is secondary,and the contribution rate of farmland is only 5.43%.It is concluded that the land use systems have distinct impacts on terrestrial ecosystem carbon storage;the carbon storage of soil ecosystem can be increased through adjusting the land use systems;although the economic forests is always under intense disturbances by people,the soil carbon storage can keep high level because of the large investing from humankind.

Abstract:The Tuojiang River, running through Sichuan Basin as a key tributary to the Yangtze River, characterizes dominant in purple soil distributions. However, over-population and irrational land uses result in serious degradation of purple soil. So as to evaluate the tensity of degradation and scavenge for productivity improvement, this study focused on surveying the soil organic carbon storage and distribution within different land uses in the Tuojiang River basin. The results showed that significant differences can be analyzed among soil organic carbon contents of forestland, orchard, vegetable garden, maize field and grass slope, which were measured as 13. 876, 9. 655, 9,261, 6. 134 g/kg and 7. 968 g/kg, respectively. The dissolved organic soil carbon content also embodies the same changing trend. In different sections of the Tuojiang River basin, soil carbon content is significantly higher than those in the lower reaches, but complicate changes can be investigated between the middle and the lower reaches. A general tendency is that organic soil carbon content in the upper reaches is higher than those in the lower reaches, and that those in the middle reaches is the lowest in amount.

Abstract:It was carried out to examine the characteristic of soil properties and their spatial heterogeneity on the comprehensive observation field of Iinze farmland ecosystem network using methods of classical statistics and geostatistics. The results showed that the variance coefficients of soil organic C, total N, available N, available P, available K, pH and electrical conductivity were more than 20% except pH. The range of soil organic C and total N were 13.8 m and 12.6 m, which indicated the high degree of spatial variability. The kriged soil properties distribution maps showed the same result. Taken 10% as a relative error, collecting 124 soil samples only could reach the significance level of 95 %. As long-term observation field, sampling subarea and field uniformization could be taken on. A more precise sampling scheme could be made based on spatial distribution pattern of test soil properties.

Abstract:An experiment was conducted to investigate the effects of earthworm activities on soil microbial biomass,activity(basal respiration) and community composition(sole-source carbon utilization,SCU) in a six years rice-wheat rotation system.Five treatments were included: control(CK),straw mulching(M),straw incorporation(I),straw mulching and earthworm inoculation(ME),straw incorporation and earthworm inoculation(IE).The presence of earthworms had significant effects on soil microbial biomass,microbial activity and the ability of carbon source utilization by microbe.Microbial biomass increased in the presence of earthworms irrespective of the way of straw application.Soil microbial activity,richness and biodiversity all decreased in the presence of earthworms under straw mulching method,and the reverse was true under straw incorporation method.It was indicated that soil microbial community composition changed significantly under straw application and earthworm activities using BIOLOG carbon utilization analysis.

Abstract:The dynamic changes of soil enzyme activity in rhizosphere of two spike-type winter wheat cultivars with different planting densities were studied under field experiments. The results indicated that the activities of protease, catalase and urease of two spike-type winter wheat cultivars presented a single-peaked curve along with growth stage. There appeared the higher values in jointing and heading stage, and the lower values in reviving and anthesis stage. There were different trends of soil enzyme activities in rhizosphere of two spike-type winter wheat cuhivars. To the Yumai 49--198,the activities of protease and urease increased at low planting densities but decreased with the increase in planting density , but change of catalase was not obvious. But to the lankaoaizao 8 all the three soil enzyme activity of decreased at low planting densities but enhanced with the increase in planting density. In addition, the variance analysis showed that the activities of protease and urease reached significant level among different treatments.

Abstract:以冈优22、Ⅱ优162和K优047为材料，通过大田试验研究了不同种植方式对土壤肥力、根系特征、根系伤流液和地上部干物质积累的影响。结果表明：免耕高留茬抛秧处理促进了土壤肥力提高，水稻成熟期其有机质含量、全氮含量、全钾均高于常耕插秧、常耕抛秧和移栽前的基础肥力，同时速效氮、钾含量也有明显提高。免耕高留茬抛秧前期根系和地上部的生长量均较低，拔节期总根长和根数均大大低于常耕插秧，也低于常耕抛秧。但免耕高留茬抛秧延缓了后期根系和地上部衰老，抽穗后30d根系伤流液强度显著或极显著高于常耕抛秧和插秧。

Abstract:With the way of runoff plots, effects of the different ways of sod in the eroded slope orchard on soil erosion, soil fertility, fruit tree growth, the output and quality of fruit were studied. The result showed that three different sod ways of strip covering and mulching, covering in the whole orchard, and strip covering could controlled soil erosion effectively and improved soil fertility. The way of covering in the whole orchard affected fruit tree growth badly, and had the lowest output and worst quality of fruit. Although the orchard with the way of cleaning tillage had the best fruit tree growth, the largest output and the better quality fruit, soil loss in the orchard was severely. The comprehensive analysis showed that the way of strip covering and mulching was the best way in the eroded slope orchard and it was worth popularized.

Abstract:Based on experiments, the movement of soil water from drip irrigation was studied in clay-loam, loam, and in sandy soil under the different dripper discharge and drop water. It was found in these experiments that the effects of dripper discharge, drop water and soil types to the shape of wetted body were analyzed. The horizontal and vertical movement distance of soil wetted front were good line functional relation with infiltration time on the intersection side of drip irrigation. With intersection time increasing, the horizontal and vertical advance rate of wetted front was increase. With the distance of apart from drip increasing, the soil moisture of Wetted volume from drip irrigation was in reduce, the soil moisture of wetted front on intersection side was bigger than the soil moisture of similar wetted depth. The result of study has certain guidance functions to the systematic design theory of drip irrigation.

Abstract:The water resource is short,and rational utilization of water resource,especially soil water resource is imperative on the Loess Plateau.The canopy interception,runoff,soil water and plant growth was measured and soil water supply and soil water consumption was analysed in the perennial artificial Caragana shrub land in the Shangshong eco-experiment station of Loess Plateau.The results showed that canopies' interception increase with rainfall.The runoff relation of rainfall outside forest is linear.The first factor influencing soil water is precipitation,second is canopy interception.The relationship between rainfall and soil water supply is linear.The impact of rainfall on soil water was reduced with depth decrease.The largest depth of wetting by rainfall is 170 cm in 270 cm in 2004.Along with Caragana forest start to bud and fall into fast growth period,soil water consumption was increased gradually,and soil drying was intensitied in light drought year.The soil supply increase fast and soil water storage increased,but the soil water would be used by plant by the next year in rainy year.

Abstract:通过具有壤中流测定功能的紫色土坡地径流小区的定位观测，结合物质平衡方法研究紫色土坡耕地水量的季节变异特征与平衡问题。结果发现，坡耕地玉米生长期水量的主要支出项为农田蒸散量、壤中流，分别为278．07，187．32mm，农田蒸散率与壤中流径流系数分别为50．51％，34．03％，而地表径流系数、农田蓄水率模拟值分别为7．59％，7．94％；坡耕地生长期支出总量为229．08mm，总径流系数为41．61％；坡耕地生长期径流支出具有季节变异特征，地表径流是玉米播种-拔节初期径流的唯一支出方式，其径流系数为9．32％，而壤中流则是拔节初期-收割近100天径流的主要支出方式，尤以灌浆成熟-收割前的近两月为甚；期间，壤中流径流系数最低为10．82％，最高至65，61％。

Abstract:In order to explore the resource of rain-fall under rain-fed regions of wheat-summer corn planting system,it is useful measures to combine bed-planting and strew mulching for improving water use efficiency(WUE).The experiment showed the summer corn cultivation of combinating bed-planting with strew mulching markedly increased the amount of soil water storage from 0~40 cm deep soil profile,especially in the scope of 5~10 cm,in contrast with the flatting cropping system.But the effects gradually decreased as soil profile extended deeply.The average value of free vaporizing on the top of corn population was 12.8%,7.6%,13.2% for the treatments of sole cropping with mulching,bed-planting,combinating bed-planting with mulching,respectively,in comparison with the treatment of sole cropping,but the average value of ground vaporizing 48.6%,29.9%,54.3%,respectively.The system of bed-planting and mulching improved WUE by 24.32%,and the rate of leaf losing water was the lowest among the four treatments.The results implicate that the pattern of bed-planting and mulching can effectively storage rain fall,and translate the soil water resource into plant water available at most.

Abstract:Vegetation restoration is main path of rebuilding regressive ecosystem,and species diversity of vegetation in restoration reflects level of vegetation restoration.Relation of species diversity characteristic in vegetation restoration in Taihang mountain gneissose area and soil water content were studied through investigating different closed communities.The results showed the index of the species diversity of natural shrub communities>that of artificial arbor communities.Index value is in 20 years>in 10 years>in 5 years of artificial arbor communities and natural shrub communities.Soil water content in six communities is low,but its added litter with closing and that of natural shrub communities is high than that of artificial arbor communities.Soil water content and evenness index is positive correlation,and diversity and Soil water content is positive correlation in earlier stage,but is negative correlation in closing 20 years.Elements of natural communities of shrub were recovery during short closed time from diversities of communities.Closing and stopping human disturbances and reasonable tending method are the effective measure for vegetation recovery in Taihang mountain gneissose region.

Abstract:A field experiment was carried out to study the effects of three chemical agents(including water-retaining agent,FA Handilong and mixture of CaCl2 and GA) on soil moisture content of plough player and water relation of winter wheat under different irrigational conditions at later growth stage in subhumid zone.The results showed that water-retaining agent and FA Handilong had better effects on increasing the soil moisture content of plough player,flag leaf water potential and leaf WUE,especially the water-retaining agent.In contrast to CK,the average value of soil moisture content and leaf water potential under water-retaining treatment after flower stage was increased by 9.7% and 10.8% individually under irrigating twice,while it was increased by 5.3% and 7.4% individually under no irrigation in the experiment.The mixture of CaCl2 and GA could significantly decrease rangeability of daily change of leaf water potential and WUE.By regression analysis,soil water potential determined the leaf water potential,meanwhile there was a positive correlation relationship between leaf water potential and leaf WUE.The results also showed that all these three chemical agents had different way to improve yield of winter wheat,but water was the critical factor on yield in this experiment.Under the same irrigational condition,there was no variance in yield or ears number among four treatments,but under the different irrigational conditions,the variance of yield was dramatic.

Abstract:在大田条件下，以强筋小麦豫麦34为供试材料，在330kg／hm^2（高氮）、240kg／hm^2（中氮）2个供氮水平下施用纯硫0，20，60，100／hm^2，研究了不同供氮条件下施硫对小麦光合特性及产量的影响。结果表明：在适宜的供氮水平下施硫对小麦氮同化的关键酶硝酸还原酶（NR）活性、叶绿素SPAD值、叶片可溶性蛋白、旗叶光合速率均有促进的影响，高氮条件下有随施硫量的增加NR活性、叶片中可溶性蛋白含量以及旗叶光合速率有减少的趋势。在2个供氮水平下施硫均对干物质积累量和籽粒产量影响效果明显，在N330水平下，各施硫处理的产量高低依次为S100〉S60〉S20〉S0；与S0相比，施硫处理籽粒产量分别提高了28．6％，12．6％和1．9％，S100与S20和S0相比达显著水平，S100和S60间差异不显著。在N240水平下，施硫肥处理籽粒产量分别提高了25．7％，25．3％和12．2％，S100，S60和S20差异不显著，但均显著大于S0。

Abstract:For building the ecological engineering to purify the eutrophic water, six economic plants,which are Cress,Ipomoea aqutica,leek,Chinese chives,Celery and Hemerocallis respectively,were selected,and the purification ability and the bio-ecological character of them were studied.Results show that each species has great ability to removal total nitrogen(TN) and total phosphorous(TP),especial Cress and Ipomoea aqutica,during the 20 d experiment period,the removal percentage to TN and TP is 89.5% and 98.2%,respectively;TN concentration in water declined in negative exponent form with the time continuing.The changes of Chla,BOD5 and COD were observed?during the treatment.It was found that in high nitrogen eutrophic water,except Cress and Ipomoea aqutica,the Chla,BOD5 and COD decreased with time continuing,but the acrid smell in the water aggravated during leek and Chinese chives treatment.The integrated analysis of all indices indicate that in different nitrogen eutrophic water,the purification effect of Ipomaces aquatica was the best,Cress take second place,Hemerocallis and Celery place in the center,leek was worst.

Abstract:Through investigation on the impact of environmental factors(including dissolved oxygen,pH value,temperature and disturbance) and submerged plant on phosphate release from sediment,the impact factors of environmental factors affecting phosphate release,and submerged plant affecting phosphate release under different environmental factors have been analyzed.It can be concluded that dissolved oxygen,pH value,temperature and disturbance can affect phosphate release from the sediment,among which,both dissolved oxygen and pH value are the more important environmental factors;phosphate in lakes especially the shallow ones plays an important role in water eutrophication;and submerged plant play a key part in preventing the sediment from being stirred by environmental factors such as water pervasion,winds and so on;moreover,in the shallow lakes,it is of practical value to revive submerged plant like Myriophyllum spicatum L.in the sediment under the conditions with the greater disturbances in lake,for the control of phosphate release from the sediment.

Abstract:Here,the distribution characteristics of mercury,lead,zinc in the sediment of three rivers of Huludao City,China contaminated by different pollution sources were investigated by enrichments factors using Fe as a normalizer,the ratio of enrichment factors(R) which was used firstly and correlation matrices.The Hg,Pb,Zn average contents in sediment of Wuli River which was contaminated by chlor-alkali were 663,3.21,5.51 times as high as the regional sediment background value,respectively.Those of Cishan River which was contaminated by zinc smelting plant were 1 889,64.89,124 times as high as the regional sediment background value,respectively.Those of Lianshan River which was contaminated by contaminated soil were 11.43,3.50,3.88 times as high as the regional sediment background value,respectively.The source of Hg in sediment of Wuli River is different from Pb,Zn,and the source of Hg,Pb,Zn in sediment of Cishan River is the same one.

Abstract:DOM is one of the most active chemical components in environment.It has great influence on transport and transformation of heavy metals in soil.An investigation on the effects of different DOMs,which were extracted from pig manure(DOMpm) and rice straw(DOMrs),respectively,on adsorption of Cd in the typical vegetable garden soils in Chongqing were carried out using isothermal adsorption and kinetic experiment.The results of experiment showed that the adsorption behavior of Cd was different in different soil and application DOM.In purple soil,DOMrs reduced the Cd adsorption obviously while DOMpm reduced the Cd adsorption in lower concentration but enhanced in higher one.In yellow soil,DOMrs also reduced the Cd adsorption.However,DOMpm can obviously enhance Cd adsorption by soil.

Abstract:Field experiments were conducted to study the impact of rejuvenated water irrigation on the quality of tomato, the heavy metal element in fruit and soil. The results showed that, the protein, vitamin C and organic acid contents of tomato are highest under the QG treatment,followed by HG, and are lowest under the ZG, the differences are notable. It is also discovered that the Cr, Cd and Pb contents in the fruit increased with the advance of the irrigation volume of the rejuvenated water, the differences are not distinct. The accumulation of the heavy mental element in the fruit was not founded with the use of rejuvenated water and the data received in the test were far less than the Chinese National Standard. The difference of the heavy mental element contents in the soil was also not distinct and the data were far less than Chinese National soil quality standard either. The rejuvenated water was used in the experiments. The conclusion is that the short-term irrigation using this water only reduced part of the tomato qualities; heavy mental element was cumulated in neither tomato nor soil.

Abstract:研究了深圳市1991～2004年的酸雨时空分布、降雨化学组成及其成因分析。结果表明，深圳市酸雨14年间pH平均值为4．98，酸雨频率为44．2％；降雨中SO4^2-与NO3^-比值是3．78：1，低于全国平均值6.4；酸雨夏秋两季较为严重，主要集中在3～9月份，而冬春两季降雨酸度和酸雨频率均较小；酸雨强度由西向东依次减弱；降雨中离子来源主要是工业和交通排放的酸性污染物，但陆地源和海洋源对降雨酸度的影响也较大。

Abstract:Miyun reservoir,the mere surface water source of drinking water in Beijing,is facing with serious threat of eutrophication in recent years.Non-point source pollution has become the primary factor resulting in water quality deterioration when point source pollution was gradually controlled in the Miyun reservoir.Nonpoint source pollution has remarkable variation on spatial distribution and the pollutant coming from specific landscape units usually accounts for the majority of the pollutant load in watershed.These landscape units are the critical nonpoint pollution areas.Measures should be taken on them in order to control nonpoint source pollution with limited resources.As a simple model developed in past years,the USLE(Universal Soil Loss Equation) is still one of the most widely used soil erosion models through continuing revisions and modifications presently.Because the parameters of USLE are relatively simple and easy to obtain,this model integrated with GIS may be used in soil erosion investigation in large regions.Based on the widely used GIS platform,the USLE is used for raster calculation to create the distribution map of critical nonpoint source pollution areas in the Miyun reservoir watershed.The distribution map produced in this study may provide helpful reference for the further investigation on the identification of critical areas for the nonpoint source pollution.

Abstract:采集了太湖地区3种主要水稻土（白土、黄泥土和乌栅土）的原状土柱为供试土样，利用CT扫描技术，在不破坏土体结构的前提下，准确地得出了不同深度土壤剖面上各种大孔隙的数量、面积以及分布状况。结果表明，3种水稻土均以表层的大孔隙度最大，在30～40cm处达到一个最低点，再往下又呈波浪形变化。土柱各截面上大孔隙面积的变异系数随着深度的变化与大孔隙度相似，大孔隙度大的层次其变异系数也较大。等效直径越大的孔隙（〉5mm）在土壤不同深度下数量的变化也越大。表层上大直径（〉5mm）的大孔隙较多，在土壤剖面30～40cm以下其数量急剧减少；而直径较小孔隙（〈1mm）的数量在土壤剖面不同深度下相差不大。

Abstract:The agricultural ecological and economic security of watershed means that a sort of situation which satisfy sustainable development of ecological economy of the watershed,containing 3 levels of contents and 3 important characters.According to the current status of the watershed in the loess hilly and gully region,the situation of agricultural ecological and economic security of the watershed can be divided into 4 grades: security,sub-security, insecurity,extreme insecurity,a majority of the watershed has been under the state of sub-safety or insecurity;Take Zhifanggou valley as an example,the author analyses the practical performance of the system in sub-safety situation.Researching on the main problem caused by the system in the situation of sub-safety or insecurity,the author put forward the countermeasures and suggestions: Developing ecological agriculture with commodity economy,and consolidating the coupled relation between industry and resources;Adjusting industrial structure and advancing industrial optimize and upgrade;Building up early-warming system of agricultural ecological and economic security of the watershed,and adjusting input of matter and energy outside the system in time.

Abstract:Taking the lower reaches of Huolin River, which is in arid and semi-arid regions of China, as study area, the land-use spatial data was built on the basis of topographic maps in year of 1954 and 1964, and remote sensing data of 1986, 1996 and 2000. With the spatial analysis model and cumulative transition probability being introduced in the analysis of land use dynamic changes and transition procession during study periods, the land use variations along the lower reaches of Huolin river in the last 50 yeas were discussed. Results showed that the infield and grassland, followed by salinized land took the leading place, the proportion of wetland, woodland, residential land and sand land was relatively low. All the time, the infield and grassland were changing in opposite directions, which indicated close inter-conversion relationship between them two, while the residential land and salinized land varied in opposite directions all the way, from which we could conclude that human disturbance activity was the main factor for the expanding of salinized land. The fastest transition speed of sand land indicated that there was a relatively larger space for amending the sandy condition. The substrate function of infield could be seen from its lowest transition speed. The area of grass land dropped from the order of second to third for its relatively fast transition speed. The transition changes among different land-use types varied significantly. As to lands of identical use type, the types of transition inputs and outputs, as well as the transition magnitude, showed obvious differences and had tendency to varying with time. The dynamic changes of various land-use types in different intervals were controlled by the reduce function of transition outputs overlaying with the increase function of transition inputs.

Abstract:The desertification of agriculture and pasturage interlaced zone of northern Shaanxi of China from 1986 to 2000 was monitored through three sets of the multi-temporal remotely sensed data of TM,acquired in August 1986,July 1993,and August 2000.Based on the RS and GIS,this research attempted to monitor on the desertification landscape structure process.The results showed that the extent of desertification has spread while the overall severity of land degradation,and it's patches congregated and expanded,while the landscape of sandy desertification becoming more fragmented.Fortunately,the degree of the sandy desertification had manifested declining,because the severe desertification area had decreased 121 474.5 hm2 and the moderate desertification was taken in the leading position rather than severe desertification.But slight and moderate desertification had to faced potential danger that may convert to severe desertification due to human activities and droughty climate.The spatial centroid of desertification landscape patches expanded to the southwest and northeast from 1986 to 2000.Furthermore,the sandy desertification extent is continuously to the southeast and northeast loess gully and hilly areas with catenaries,the whole situation of sandy desertification becomes serious and serious.

Abstract:Basing on the sketch date of land use in the year of 2000,using the more explicit landscape metrics we quantify and analyze the landscape spatial pattern in Horqin sandy land and in term of regions and banners to reflect the affect of landscape pattern on regional eco-environmental.The result shows:(1)Grassland landscape is the biggest in area,the most extensive in distribution,and the strongest in consecution substrate landscape in Horqin sandy land.Its area proportion is 47.6%,patch number proportion 29.8%,average patch area higher than 3.25 km2/per,patch dispersion index only 0.40.The area proportion of farmland and woodland is also great by 26.3% and 10.2%.The area proportion of mobile sandland which is 5.8% and alkaline land which is 3.1% is small.(2)The Banners,counties on the alluvial plain on both side of the downstream and bayou of western Liaohe River.The landscape pattern on the regional reflects the feature of mosaic of substrate landscapes of farmland,mobile sandland and grassland.(3)The correlation analysis shows,there is a remarkable positive correlation between the eco-environmental index and the average patch area of the landscape,and that there is a negative correlation between the fragmentation index of landscape and the eco-environmental index.

Abstract:By using thermal dissipation probe,sap flow of Pinus elliottii was measured with the circumstance factors recorded by radiation,temperature and humidity sensors.There was a high correlation between sapwood area of P.elliottii and diameter at breast height by quadratic function.Regressional analysis on the sap flow of P.elliottii in different growing periods and sapwood area showed that daily cumulative sap flow correlated linearly with sapwood area with all correlation factors higher than 0.95.Significant correlations also existed between daily cumulative sap flow per sapwood(qs)and three separate ambient environmental factors including canopy temperature(CT),canopy relative humidity(CRH) and photosynthetically active radiation(PAR).Multiple linear models of qs and environmental factors were developed at significant level,of which the sequence of correlated degrees was as follows: CRH>PAR>CT.