Abstract:Critical conditions for rill flow erosion on hillslopes are investigated using numerical simulation and laboratory data for large variation in slope gradients. Several factors have been considered in this study, i.e., slope length, gradient, projected length on a horizontal plane, etc. Shear velocity is used as the parameter for establishing a critical condition, and two cases have been considered,i.e.,(1) the critical shear velocity may change with slope gradient, or (2) it may not change. For given plot size, net rainfall intensity and original topography, the minimum slope gradient has been found out at which shear velocity of rill flow can achieve the critical value.

Abstract:Based on the quantitative analyzing of the similar topographical characteristics and classification of Caijiahuan watershed and its 6 branches by system clustering analyze of MATLAB in the Loess Plateau, the western Shanxi province, impacts of the forest coverage and land-use types on runoff in small watersheds that are similar topographical characteristics were researched in this paper. From the result of analyze, forests have the function of decreasing amount of rain season runoff. Amount and process of runoff in watershed were impacted by forest coverage. By favorable measure of soil preparing, artificial forests have evident function on adjusting runoff and decreasing amount of peak flow of rain season.

Abstract:根据直线和网格布点法布置的150个取样点的测定资料，应用经典统计分析方法．探讨了垦荒地土壤电导率和重量含水率的空间变异性，并给出了不同置信水平及精度要求下两者的合理取样数目。应用自相关和半方差分析方法进一步讨论了土壤电导率及土壤重量含水率的空间变异结构和半方差函数模型。结果表明，垦荒地土壤电导率和重量含水率的空间变异都是有结构的，土壤电导率的最大相关域为9m，土壤重量含水率的最大相关域为6．4m。两者的半方差函数可用有基台的线型模型拟合。

Abstract:Phosphorus, Cu and Zn concentrations in surface water are controlled by a complex reaction of soluble P, Cu,Zn with sediments. This study investigated P,Cu,Zn concentrations in solution when various sediments were mixed. In the system where two or three sediments were mixed, the measured soluble P, Cu, or Zn concentration were always lower than the predicted values caclulated based on the compositions of sediments, indicating the soluble P, Cu or Zn released by one sediment could be resorbed by another sediment. This resorption may result in lower than expected solution P, Cu,Zn concentrations in some surface water. Soluble P, Cu, and Zn concentrations in water where the sediments came from multi-sources were controlled mainly by the sediment that had strongest adsorption capacity to P, Cu,Zn, or strongest potential to release P, Cu,Zn.

Abstract:Pot experiment on red soil(garden soil) contaminated by heavy metal in Guixi city,Jiangxi province was conducted.The results indicated that using lime to tune soil pH to lightly alkalescence could improve net photosynthesis significantly,increase soil microbe C (especially for cellulose-decomposing bacterium),reduce the available content of heavy metal and reduce the harm to plants,so it's the viable amended measurment under the condition in existence.

Abstract:Huaihe river,one of the seven greatest water systems in China, was serious water environmental pollution makes water resources more rigorous, and seriously hampered the sustainable development of the Huaihe basin. The article puts great emphasis on the river basin analyzed water pollution of the environment present condition in Anhui segment, and then studied the main factors and reasons of the effects of the social economic development on the water environment in Huaihe river. Finally produced the measures to improve the water environment, including the adjustment of industrial structures, improvement of recycle utilization rate of water resources, construction of urban contaminated water plant, cleaning production and so on. Therefore, some effective countermeasures have to be taken, to combine two apparently contradictory objectives-wastewater concentration control and total amount control.

Abstract:This studied the effect of fertilization on NO~-_3-N leaching of field ecosystem of dark soil utilizing D-statured optimum design, it indicates that after fertilization NO~-_3-N concentration and NO~-_3-N quantity in the leaching liquid in corn field ecosystem dominated by the quantity of nitrogen fertilizer of application. The application of nitrogen fertilizer reduces the quantity of leaching liquid, but the concentration of NO~-_3-N and the total quantity of NO~-_3-N increase. The reason of increase of total quantity of NO~-_3-N is that the increase of total quantity of NO~-_3-N leaching liquid. The application of phosphate fertilizer increases the quantity of leaching liquid, but the concentration of NO~-_3-N and the total quantity of leaching liquid reduce. The reasons of reduce of total quantity of NO~-_3-N leaching liquid is that it reduces the content of NO~-_3-N in leaching liquid. The application of incorporated nitrogen and phosphate fertilizer reduces the content of NO~-_3-N and the total quantity of NO~-_3-N leaching liquid .The reduced quantity of leaching NO~-_3-N is just the increased section after applying nitrogen fertilizer. Organic fertilizer reduces the quantity of leaching liquid, so the total quantity of leaching liquid reduces, but the content of NO~-_3-N in the leaching liquid increases.

Abstract:Taking Huangfuchuan Basin of the sand-laden and coarse sand areas in the loess plateau as an example mainly, the effect of flood retention and sediment reduction with different allocation system of water-soil conservation measures has been analyzed according to field observed data. The concept of "Measure allocation ratio" and "Basin harnessing effect related to typical allocation scheme of water-soil conservation harnessing measures" has been pointed out. The research result shows that if the allocation ratio of single measure is different, the effect of flood retention and sediment reduction of measure system will be different in the water-soil conservation harnessing measures system; when the allocation ratio of desilting dam is lower 2%, the benefit of sediment reduction of basin harnessing is small; if the controlling area of dam-reservoir is about 10% smaller than the total area of the basin, the controlling effect of basin harnessing measure system is not still obvious, though the harnessing degree of other measures is up to 45% or so, the mean precipitation of surface is larger than the storm flood with 35 mm and the maximum daily precipitation is larger than the storm flood with 50 mm.

Abstract:Use GIS and RS, analysis the TM images in 1994 and 1998 about Minqin County. The result show: somewhere in Minqin county desertification has been controlled, the same time somewhere been exacerbated. Around the Minqin oasis desert control is successes, the area of shrub become bigger. But beyond the oasis, the area of sandy grassland and salt grassland have been reduced 13.8% and 0.3%, the flow dune increased 0.3%. The reason of desertification is irrationality use water resource, overly graze on the grassland and overly bring under cultivation around the oasis. In the model area, Xishawo of Minqin, locates the tile of badanjiling desert and before Minqin oasis, after some years control, the land, and the forest are stable increased, the desertification in model area has been reversed. In the future, along with the fall of ground water, the degeneration of vegetation should be the major exhibition of desertification in Minqin County. We provide some advice for the control of desertification in Minqin County.

Abstract:采用多时相陆地卫星TM数据,以分类后比较法和历史土地利用专题图支持下的目视检测方法进行黄河口耕地变化动态监测.建立了基于TM数字图像的耕地变化及其相关自然和人为因素变化的指标,对与耕地变化相关的自然环境要素变化及人为影响进行了分析.结果表明从1987～1998年,垦利县耕地增减变化较大,面积减少了5 321.8 hm2,平均每年减少483.8 hrn2.耕地的变化反映出该区土壤盐渍化的加重和水源的匮乏,以及人为不良活动的影响.在此基础上提出了该区生态环境安全的对策措施.

Abstract:Using digital satellite remote sensing TM data, the monitoring of cultivated land changes in the region of Yellow River mouth were carried out by methods of classification results overlay and land use map supported visual change detection. Indices of cultivated land change as well as its related natural and human-related factors were derived from TM data. Correspondent natural environment factors and human influences were analyzed accordingly. Results show that obvious change in cultivated land occurred in Kenli County, which decreased by (5 321.8) hm~2 from 1987 to 1998, i.e. 483.8 hm~2 every year. These changes indicated the aggravation of soil salinization, and the influence of adverse human activities. The countermeasures of ecological environment security of the study area were proposed.

Abstract:Based on the basic fractal theory and GIS technique, the topographical fractal character of Chabagou watershed, which lies on loess plateau, is studied, the model and method that are used to calculate the fractal information dimension of the topographical fractal character of the watershed is put forward, and the fractal information dimension of the topography of Chabagou watershed is worked out. The results show that the fractal information dimension of the topography of Chabagou watershed is less than 1, and the relationship of positive correlation presents between the watershed area and the fractal information dimension of the topography. The fractal information dimension shows the quantitative character of the complex essence of watershed topography, and has provided with new solution for quantifying the macro-topography, which is one of the very important indices of the small watershed soil erosion prediction model on loess plateau.

Abstract:Aiming at issues of natural vegetation cover area continuous reduction and eco-environment deterioration, the present situation of natural vegetative cover and its existing problem was detected clearly first adopting jointly methods of field investigation and current research results collection. Analysis results for vegetation cover degeneration reasons deduce that protection measures should include the following: to enlarge drylot feeding scale, control livestock number according to bearing capacity of grassland, increase water supply and enlarge irrigation area, develop reforestation, construct small scale artificial biosphere, and so on.

Abstract:The serious soil erosion, natural-ties, environment pollution, land degeneration in Sichuan province is resulted by natural and social environment: the former including a vast territory, complicated environment and distinct area difference, the latter including lack of agriculture ecological environment protection consciousness, becouse of attention on short-term economic benefit, and increasing of man-land contradiction. Therefore, in order to restore and reconstruct agriculture ecological environment, People in Sichuan province must intensify consciousness of preserving agriculture ecological environment, strengthen macroscopical government instruction, change economic pattern, enlarge technology popularization, develop ecological agriculture, adjust industrial structure, spread paid utilization policy of resources, and carry out soil and water conservation and environment pollution measures.

Abstract:A case study from "Huangxin" immigrant high efficiency ecological agriculture exploiture area in Wuqiao, Wanzhou borough of Chongqing, based on the structure and fuction and benefit of orchard ecosystem of Three Gorges Reservoir,the problems of why they are not in reason are found. The strategies,including how to use such a great opportunity to optimize orchard ecosystem and develop fruit industry coming from Three Gorges Project,is put forward by investigating and experimenting in Three Gorges Reservoir in two years.

Abstract:The shortage of water make it necessary to collect the rainfall. Cellars are used widely for their advantage of less area,less material,lower fee and better quality water. The necessary of main types, construction and the relevant present problems of the cellar are deeply analyzed. Some advisements are put forward and the prospective is predicted. The purpose direct what we should research on the point in the future.

Abstract:Through the long-term plot study on the litter and its decomposition in the evergreen broad-leaved forest in Hangzhou for more than two years, it was resulted that the annual litter production was 5.85 t/hm~2, most of which was the fallen leave (79.5 percent) and the withered branches and fruits were far less (7.1 and 13.4 percent respectively). The dynamics of the fallen litter was shown as a curve of two-peak pattern which appeared in April and September each year. The half-life of the litter was 1.59 a. The decay rate of the litter attenuated as an exponential function. The annual amount of the nutrient returned to the ground through the litter was as large 223.69 kg/hm~2. The total current amount of the litter on the ground was 7.47 t/hm~2 .The decay rate in the first half of a year was 45.18%. The stand remained in the stage of litter increasing with time.

Abstract:分析了黑土腐殖质、黑土母质、黑土区气候、地貌、植被及人类开垦等活动与黑土侵蚀之间的关系，指出了黑土区农业开垦与耕作是导致黑土流失的主要原因，同时，在人类干预条件下，某些自然因素对黑土加速侵蚀的影响就会明显地凸现出来。实际上，黑土区独特的自然环境与人类活动方式已经使其成为目前中国土壤侵蚀潜在危险性最大的地区之一。目前，黑土流失速度相当快．不少地区已经出现了成土母质露于地表的现象，土壤侵蚀严重。如果我们现在还不能正确认识黑土地治理的紧迫性，黑土区很快就将变为名副其实的“不毛之地”了。

Abstract:The anti-scouring feature of soil in Xiaojiang River basin is studied by experiment. The result is that the paddy soil is the biggest in anti-scouring, the brown earth is less than paddy soil in anti-scouring, and more than the others in anti-scouring; the grassland is the biggest in anti-scouring, the farmland and scrublands is less than grassland in anti-scouring, and more than the bare slope in anti-scouring; the anti-scouring ability of soil in Xiaojiang River basin is relative to the contents of grain in >2 mm and<0.002 mm.

Abstract:从大气降水-土壤水循环系统出发,于2001～2002年在江西省余江县刘垦农场内桔园地用定位法对土壤水分与径流的坡位差异进行了研究。结果表明,由于上坡、下坡土壤的质地分异,雨季上坡水势值总体上高于下坡,而旱季上坡水势值基本上低于下坡,相对应的土壤水分150cm贮水量及收支平衡也有明显的差异;用径流小区法测定的径流表明,旱季10mm降雨上坡、下坡径流深度为0.596,0.585mm,但雨季上坡、下坡10mm降雨径流深度为0.429,0.488mm。为土壤水分适时调控、节水定量灌溉及分析养分迁移提供依据。

Abstract:The dispersion coefficients of electrolyte solute in flow of different slope and sediment concentration are calculated using the mathematical model of electrolyte pulse transferring in laminar flow. The dispersion coefficient is liner related to the velocity of flow when the sediment concentration is relatively low; The sediment concentration is high, it affects intensively the dispersion coefficient, and make their liner relationship bad. These results shows that the relation between dispersion coefficient and sediment concentration and velocity deserves to more discuss.

Abstract:Dianchi Lake has been listed the focus of national river bodies' harnessing, which attracts special attention in the conservation of Yunnan's nine major plateau lakes. Slice pollution is regarded as the primary cause of pollution of Dianchi Lake, and soil erosion, which accounts to 80% of the pollution amount, is the source of slice pollution. Soil erosion is the fundamental element contributing to environmental determination of Dianchi Lake, and the prevention of soil erosion is central to the harnessing. Based on the analysis on TM data in the year of 1987 and 2002 with RS and GIS, and changes of soil erosion distribution, alterations of area and intensity the result that soil erosion become slow are obtained; while the analysis on data about the dynamic change of forest coverage and land use indicates that the increase of forest coverage is the major contribution of soil erosion change. In conclusion, suggestions concerning water and soil conversation are put forward, such as speeding up shelter-belt system, developing ecological agriculture and strengthening legal education.

Abstract:According to statistical material and analytic data of soil related, the farmland nutrients balance and the dynamic changing tendency of the main soil nutrients from 1985 to 1999 in hilly areas in the middle basin of Sichuan were discussed through Zitong, Zizhong and Qianwei counties. The results showed that after 1990, the nitrogen in farmland was changing from equilibrium to surplus, it was surplus over 35 percent; the phosphorus was surplus over 40 percent; the potassium was deficient all along with high proportion, it was deficient nearly 50 percent. Meanwhile, comparing the content of soil nutrients between 2000 and the second soil investigation, the effect of farmland nutrients balance on soil nutrients level was discussed also, thus the regulating ways relevant was given for sustainable farmland development.

Abstract:Based on the background of water distribution of Heihe River, it analyzes the urgent situation of water shortage and the effects of the land use structure on it in the middle reaches of Heihe river after water distribution. Because of the close correlation of the rational application of water and land resources in the arid area, reasonable land use structure can make water more effectively used. Due to the above reasons, it argues that the water shortage restriction should be solved by reasonable optimization of land use structure; in addition, it also puts forward the main direction of land use optimization.

Abstract:The resource and environmental quality evaluation is carried out in the Houhu farm enterprise of Jianghan Plain based on Arc/Info and the press-state-response model(PSR) which selects the soil integrated pollution index as a pressure index. The evaluation results can provide gist for reasonable land-utilization programming and environmental protection. To begin with, the factors affecting resource and environmental quality are decided by Delphi and PSR model and the weight of corresponding factors is calculated by AHP method. Then Arc/Info is used to establish spatial database by digitizing relational layers and developing buffer analysis. Furthermore, according to membership function of evaluation factors, original data of the specimens and the synthetic index method, environmental quality indexes of assessment units for cropland are calculated and the quality grades are divided by frequency distribution of synthetic index values. Finally, the map and data set of results in the Houhu farm enterprise are obtained automatically with Arc/Info. Results indicate that the environmental quality in this area is in medium and high side, the percentage of area in level 2 and 3 amounts to 47.27% and 35.83% respectively. By analyzing correlation between the soil contaminated status and environmental quality of cropland, the prominent plus correlation exists between both.

Abstract:系统研究了济南市南部山区不同林分类型在保育土壤方面的生态功能,采用机会成本法、市场价值法、影子工程法等对4.59万hm2的山区森林在保育土壤价值方面进行了经济核算,结果表明,单位面积上每年减少土壤侵蚀量的大小为乔灌混交林＞阔叶林＞灌木混交林＞针阔混交林＞灌木林＞针叶林;不同林分单位面积培育土壤肥力的大小为针阔混交林＞乔灌混交林＞灌木林＞阔叶林＞灌木混交林＞针叶林.合计每年森林保育土壤的总价值为9 734.59万元,其中森林减少土壤流失,防止土地废弃的价值为97.74万元,减少土壤肥力损失价值为5 925.79万元,减少泥沙淤积滞留的损失价值为372.80万元,培育土壤的价值为3 338.26万元.

Abstract:This paper with the Weining county Guizhou province as a case study. The advantages in pastoral animal husbandry development and some problems of development were discussed through analysis of the natural resources and ecological economic condition in Weining. Put forward an ecological protection and pastoral animal husbandly ecological economic development pattern in according with the quantity of heat and altitude divided, which contains sheep and goats system of high mountain pastoral areas, beef cattle system of middle mountain agricultural and pastoral areas, dairy cattle system of valley agricultural areas,and act according to the principles and take policy in Guizhou karst mountain region. It is sustainable development pattern that bring about a combines pastoral development with ecological protection and social results.

Abstract:Based on Zhangbei's special climate and topical environment, different models were put forward for effective utilizing resources of water and land, and the techniques that matched agro-saving water were summarized, according to the requirement of the food production and eco-environment improvment. All the measures were aimed to improve the production efficiency of water and land resources, construct high effective agriculture and stock raising, increase income and eco-environment for local residents, and form a "green gate" and defend barrier for Beijing and Tianjin, by decreasing the area of cropland, stopping excessive farming or grazing, regulating agricultural structure and developing agro-saving water techniques.

Abstract:Poyang Lake is the largest fresh-water lake in China, which is formed by the swallowing and spiting of Yangtze River water, and so is called the natural regulator of Yangtze River water level. As a special wetland ecosystem, Poyang Lake is rich with various wetland effects. The main ecological functions of Poyang Lake include storing water; regulating river level; adjusting climate; purifying water, soil and air; fixing C and releasing O_2; controlling erosion; protecting soil; nutrition circling; being habitats. The direct products include supplying water, producing plant, animal and energy; water transporting; being research and education site; the lake is directly the entertainment/tourism place. Poyang Lake wetland ecosystem has biodiversity and social importance.

Abstract:Alley cropping (or contour hedgerow intercropping) has been developed and promoted in the tropics since early 1970s. Alley cropping has been regarded as a promising agroforestry technology for conserving farming and sustainable use of sloping lands in the humid and sub-humid tropics of Africa, America and southeastern Asia. It was introduced to China in the beginning of 1990s. Satisfactory progress has been achieved in research and demonstration in dry valley of the upper Yangtze River and in Three Gorges Region by integrating local needs with natural resources. Achievements of studies and extension of contour hedgerow intercropping in China during the past decade are reviewed, which shows hedgerow intercropping is suitable for soil and water conservation, soil fertility amelioration, land productivity improvement, and bio-terrace formation in mountains, and increased options for income generation based on local resources. Some misunderstandings of the system in China are cleared and some suggestions for further research are also presented.

Abstract:Based on the theory of landscape ecology, it analyses the processes of wetland changes in middle-lower reaches of Taoer river between the year of 1986, 1996, 2000, and discusses the characteristic of wetland change in its quantity and wetland landscape pattern's dynamic, the driving forces also. It pointes that wetland represents apparently declining trend in quantity and scope in recently ten years over, with natural wetland's transformation to artificial. Hydrological factor is direct cause of wetland's change, and natural and artificial factors affect it by different intension and manner.

Abstract:Study of catchment LUCC is present focus of global change research. Based on the interpreted Landsat-TM image data and the support of ArcGIS software, this paper uses the conversion matrix of land-use types, synthetical land-use index and spatial centroid model to discuss the land-use change in Taoerhe catchment during the last 15 years. Results show farmland area increases and forest coverage decreases obviously. As the important hydrological and climatic adjustor in Taoerhe catchment, waters area also decreases a few. Forest coverage in the upper reaches decreases and most these disappeared forest land has been changed into grassland, and the spatial centroid of forest land moves southeastward of the Taoerhe catchment. Although most the disappeared forest land has been changed into the grassland, grassland area increases a little, because large area of grassland in the middle and lower reaches has been reclaimed into farmland, leading to northwestward moving of spatial centriods of grassland and farmland. The synthetical land-use index shows during the last 15 years land-use intensity in Taoerhe catchment also increases obviously. The overall trend of land-use change indicates a certain extent of degradation of eco-environment in Taoerhe catchment during the last 15 years.

Abstract:On basis of the interpreting of remote sensing data and overlaying of vector data, the distribution and change law of land use and cover with change of slope and aspect and the influences of the slope and aspect on the single dynamic change degree and comprehensive dynamic change degree were discussed by applying the function of GIS to manage the spatial and attribution data. The positive and negative effects of social driving force on the land use and cover dynamical changes were analyzed in this paper. The research results indicated that human activity, which is extending to terribly steep slope slowly, mainly centralized in the lower area. In Daninghe River watershed, steep and terribly steep slope farming land distributed too much and forest land distributed too little, which have a negative effect on environment.

Abstract:Gully erosion, doing much harm to land resources by encroaching upon cropland, is well developed in Yuanmou Basin. The impacts of LUCC on Gully Erosion of Yuanmou Basin, including the impacts of different land use and community structure in gully watershed on headward erosion and the impacts of vegetation coverage on gully floor on headward erosion, were analyzed with the field-surveyed data of 17 gully heads in 9 gullies of successive 3 years. Results show that LUCC make a great impact on gully erosion, which can be reflected by the following aspects: (1) Different land use in gully watershed has an obvious impact on the speed of gully headward erosion, the fastest in bare land and the slowest in woodland. (2) The gully headward erosion of bare land and grassland in watershed has a positive correlation with rainfall. (3) Shrub-grass or tree-shrub-grass structure with a high coverage rate can effectively inhibit gully headward erosion in gully watershed and the simplex structure of grass or shrub is of less use. (4) The higher the vegetation coverage rate is on gully floor, the slower the gully headward erosion is.

Abstract:Sustainable land use was an important basis of sustainable development strategy. Sustainable land use of Three-Gorge reservoir area in Chongqing was the condition to maintain ecology environment,ensure economy develop healthily at high speed. Immigrant settlement region of Three-Gorge reservoir area was an important region with the best active economy,the biggest land supporting capacity and the sensitive ecology. On the basis to analyse cheracteristics of land use, present situation of society in immigrant settlement region, comprehensive levels of sustainable land use were evaluated and limited factors and reasons for sustainable land use were expounded systematically. The main limited factors for sustainable land use in settlement regions included social and economic development level and industry structure disparity, optimal allocation level of land use, citified development level, resources and environment issues, support poverty population and extra labor diversion.

Abstract:Spatial distributions of total nitrogen in soils are difficult to estimate because of their inherent spatial variability and because of lack of ample data.Based on 151 sample data, spatial distribution characteristic of total nitrogen was studied.Correlations between total nitrogen and topographic factors were analysed.Regression model was established through linear regression analysis.The result showed:mean content of total nitrogen was 1.06 g/kg in topsoil.Sandstone and shale showed the lowest average TN content (0.88 g/kg soil),phyllite showed the highest average TN content (1.35 g/kg soil) .TN content between 0.5 g/kg and 1.0 g/kg has the biggest area (1 583.7 km~2) from spatial distribution,TN content exceeding 2.0 g/kg has the smallest area (126.7 km~2).Aspect among topographic variables had an important influence on TN content.The correlations with TN content and parent rocks, elevation, aspect were positively significant (P<0.05),The correlation with slope and TN content was no significant.Spatial distribution of TN content could be forecasted by using linear regression model.

Abstract:A machine-learning approach to automated building of knowledge bases for soil mapping was presented. Classification tree algorithm was applied to generate knowledge from training data. With this method, building a knowledge base for automated soil mapping is easier than using the conventional knowledge acquisition approach. The knowledge base built by classification tree was used by the knowledge classifier to perform the soil type classification of Longyou area, Zhejiang Province, China using Landsat TM bi-temporal imageries and GIS data. To evaluate the performance of the resultant knowledge bases, the classification result was compared to existing soil map based on field survey. The accuracy assessment and analysis of the resultant soil maps suggest that the knowledge bases built by the machine-learning method was of good quality for mapping distribution model of soil classes over the study area.

Abstract:运用可拓学中的物元理论和优度评价法,构建了土地整理立项决策评估的综合评判物元模型,给出了基于关联函数的可拓评估方法,并以国土地资源部土地整理中心备选项目库的项目进行实例验证。模型输出的结果与项目实际可行性完全吻合,研究结果为土地整理立项决策提供了新的评估方法。

Abstract:Photosynthetic characteristics and energy value of H. rhamnoides were analyzed. The results show that: (1) photosynthesis of H. rhamnoides was limited by stomatal and non-stomatal factors under drought condition;(2) If water condition was improved, stomatal conduction would been normal, and stomatal conductance could not be impacted by drought during the early stage of growth season, but it was impossible that photosynthetic capacility was recovered; (3)Energy value analysis shows that energy accumulation could not be completed until the end of growth season under drought condition, so the growth in next year was impacted, furthermore, which led to death of the plant.

Abstract:The experiments of different mulching methods were conducted at the agrometeorological experimental base of Chinese Meteorology Administration. The objective was to investigate the effects of different mulching methods on the diurnal variation of photosynthetic rate and water use efficiency (WUE) for summer maize, and to investigate the physiological and ecological mechanism. The experimental results are as follow: The most notable difference of diurnal variation of photosynthesis rate was observed at the morning, The Pn of the mulch is higher than that of CK. The leaf WUE was more high than CK, especially, in afternoon. It shows that mulch improve the leaf WUE, and ultimately improve yield WUE.

Abstract:By means of artificial control four gradients of soil water content (SWC) were established under natural condition, transpiration rate(Tr) and net photosynthesis rate(Pn) and environmental factors of Oriental Arborvitae were measured in runoff forestry research station at Fangshan county of Shanxi province from April to October in 2002. The results show that Tr has a close relation with SWC. It significantly decreases with decline of SWC, and the severer soil water stress, the earlier time of peak of Pn. As the SWC do not induces soil water stress, the diurnal changes of Tr accord with the diurnal change of radiation intensity and temperature. Under the situation of this research, the water stress of Oriental Arborviate appeared as the SWC was below 5.79%, and it became smaller when the SWC approached to 6.50% in spring, while it was very severe below 6.94% SWC in summer, no water stress was observed in autumn but Tr still changed according to SWC. This result provides evidence for measurements of runoff forestry and its effective management on the soil moisture.

Abstract:设计5种不同供水处理进行对夏玉米根系生长和底墒利用的影响试验。结果表明，有限供水对夏玉米根长的影响效应比根生物量显著，有限供水能促使夏玉米更多地利用土壤底墒，供水少，底墒利用率高，凸现出夏玉米对土壤缺水干旱的生理性适应机制和抗旱生态反应。5种供水处理以供水151．3mm，耗水190．1mm的夏玉米产量收获指数和水分利用效率最高。改变高水高产的传统耕作观念，推行有限供水，生育期内合理调配灌水量，提高水分利用效率，发挥土壤水库的调节作用，达到稳产又节水的生态农业目的。

Abstract:在水分胁迫条件下,以紫丁香、小叶锦鸡儿和乌苏里绣线菊2年生苗木为材料,叶面喷施不同浓度水杨酸。试验发现,水杨酸(SA)能有效降低水分胁迫条件下各树种叶片MDA含量,延缓可溶性蛋白质和叶绿素含量的下降。对各处理进行了抗旱性综合鉴定,证明了水杨酸预处理在灌木树种抵御干旱方面作用明显。7.0×10-5mol/L的SA既能显著提高丁香、小叶锦鸡儿和乌苏里绣线菊的水分利用效率,又能显著提高它们的抗旱能力。

Abstract:Based on the differences of response of dominant plant species in agriculture ecosystem, sandland ecosystem, grassland ecosystem and pine broadleaf forest ecosystem in Changbai mountain in northern region of China to CO_2 enrichment and soil drought, the possible change of different dominant plant species under CO_2 enrichment and soil drought were forecasted, and the measures to reply this change was put forward.

Abstract:It is an important method to estimate land surface evaporation of large region by using remote sensing data. With the development of remote sense and GIS technology, remote sensing evaporation model evolved from one-layer to two-layer model and four layer model. It introduces some remote sensing models of land surface evaporation such as surface energy balance system (SEBS), complementary Relationship (CR) and simplified surface energy balance index (S-SEBI), etc, and the retrial of land surface parameters is the model's main connotation from remote sensing data. The methods to derive land surface parameters such as impedance always need non-remote sensing data such as wind speed, temperature, so they restrict their application in water resources at large. Now the headway of remote sensing model is to derive land surface flux only by fully using remote sensing data.

Abstract:It introduced the research methods for plant root channels, and then discussed the research advance of effect of plant root channel on the movement of water flow and solute transport, on the sorption and diffusion in soil, and on the microbes in soil. In addition, some fields of plant root channel were suggested for the future.

Abstract:The studies on covering grass on the field of orchard shows that grass cover can keep warmth, moisture of the field, regulate soil structure, increase organic matter, and fertilize the land to improve apricot's yield and quality.

Abstract:By analyzing the properties of soil and water, the succession laws and the diversity of desert plant in agricultural development area of Kelamayi, it understands that growth and renewal of desert plant in this area rely on the precipitation. Some indexes of soil physical-chemical properties, the organic matter, total N, total K are stress factors that affected plant diversity. On the contrary, a certain increase of pH and grain-size is in favor of plant diversity. Additionally, total salts, total P and moisture in soil have potential impact on the plant community diversities.

Abstract:In order to account the finally score of quality of a slope vegetation,both the AHP judging matrix that help us to compute the scale of every evaluation targets and numerical value of some experts were used on making sure the scale of four times of the slope vegetation system.On the other hand,we also had set off the quality grade of slope re-vegetation by different scales of themselves.

Abstract:Ecological security is the core and base of sustainable land utilization. The concept and meaning of ecological security of sustainability utilization of land resources was discussed and the research contents and system was constructed here. Some assesses methods such as landscape indices and AHP were introduced. The construction of ecological security system should include changing traditional land utilization fashions, setting up land utilization alert system and strengthening maintenance and management of land ecological security etc.

Abstract:鄱阳湖国家级自然保护区位于中国第一大淡水湖———鄱阳湖西北角,是生物多样性非常丰富的国际重要湿地。保护区总面积22400hm2,栖息的鸟类有310种,数量多达数100000只。论述了鄱阳湖湿地的生物多样性,对其功能进行了综合概述和评价,针对其面临的主要生态问题,提出了相应的合理利用和保护对策。