Abstract:Based on analytical soil data in Tibet, which include 150 profiles of 17 soil types, the spatial change and affecting factors of soil CEC were discussed by statistical method. The result showed that soil CEC had obvious horizon characterics on the vast pleatu. Soil CEC decreased distinctly from southeast to northweast or from the Alpine meadow type, the Alpine steep type to the Alpine desert type. It was in southeast region in Tibet that ver- tical change of soil CEC was also obvious. Soil CEC of mountain wet-forest type soil increased upward from yellow earth in base band, and reached the highest valuable in Dark-brown earth and Podzolic soil. However, above the forest line, soil CEC decreased again form Dark-felty soil, Felty soil to Frigid soil. The spatial change of soil CEC in Tibet was mainly determined by the difference of the accumulation of organic matter. When organic matter content was low, soil CEC was greatly influenced by the clay content. Meanwhile, meadow-form soil in alpine zone was still influenced by silt content. Soil available potassium content had significant positive correlation with CEC, which indicated that soil CEC had important ability to keep potassium.

Abstract:The influences of soil factors on arbuscualr mycorrhizal fungi (AMF) were investigated in central Tibet altiplano pasture. The results showed that there were no corelation between the spore density which was defined as spore number per gram soil with mycorrhizal colonization; the effect of soil texture on AMF spore density is greatly larger than that of soil type. Mycorrhizal colonization in loam or silt were higher than that in sandy sandy soil. Soil pH showed significant correlationship with spore density, while soil organic matter content showed sig- nificant negative correlation. Mycorrhizal colonization was increased with increasing of soil oaganic matter con- tent, but decreased with increasing of soil Olsen-P content. It was also noticed that AMF well colonized cyper- aceae plants, such as Kobresia humilis and Cyperus compressus.

Abstract:The distribution laws of soil enzymes of Talimu Desert Highway Shelter-forest and the effects of soil or- ganic matter on them were studied. The results show that the activities of soil enzymes increased sharply, the dis- tribution of soil enzymes had distinct laws with time elapse and variation of space,and soil structure and nutrient status were improved with greenbelt set up under condition of irrigating by saline water. By analysis of path coef- ficient, soil proteinase had the largest direct effect on soil organic matter, neutral phosphatase, uraease, invertase, alkline phosphatase and catalase ranked in order. The interactions between pairs of neutral phosphatase-alkline phosphatase, alkline phosphatase-neutral phosphatase, uraease-neutral phosphatase, proteinase-neutral phos- phatase had larger effects on soil organic matter.

Abstract:The absorption and desorption of selenium in three kinds of soil (peat soil, bog soil and aeolian sandy soil) were studied using an isothermal adsorption approach in order to explore the effect of wetland soil properties on Se availability in Ruoergai Plateau. The results showed that SeO~2_3-Se adsorbing capacity of the reduced soil was more than that of the oxic soil, the desorbing capacity of water selenium (W-Se) and exchangeable selenium (E-Se) was higher in oxidation state than that in reduction state, but on the contrary the desorbing capacity of la- tent available selenium (LA-Se) in three kinds of soil. Soil oxidation state was helpful to improve the availability of soil Se. With the raising of pH value, SeO~2_3-Se adsorbing capacity decreased, the desorbing capacity of W-Se increased and that of E-Se decreased, but the desorbing capacity change of LA-Se was not obvious in peat soil. Soil organic matter adsorbed Se in large quantities and weakened the availability of soil Se, SeO~2_3-Se adsorbing capacity of peat soil reduced greatly, the amount of W-Se and E-Se enhanced and that of LA-Se diminished obvi- ously after getting rid of soil organic matters.

Abstract:Incubation experiment tested to the effect of nickel (Ni) applied on soil microbial activities and popula- tions constitution in yellow soils. The results showed that lower concentration of nickel helps the microbial activi- ties, but higher concentration or more than 100 mg/kg caused the activities to decrease. Studies suggest that soil microbial biomass carban, nitrogen and soil basal respiration decreased apparently with the increasing of concentra- tion of nickel. The number of decrease of microbial activity is lower in yello soil which is planted Hyperaccumu- lator plant than non-hyperaccumulator one. Moreover, the experiment revealed that soil microbial populations constitution have changed to some extent under stress pollution by nickel. The number of soil bacterial, acttino- mycetes and fungus decrease greatly compared with non-polluted soil samples. The soil acctinomycetes is the best sensitive for heavy mental pollution. Hyperaccumulator plant caused the lesser variety of soil microbial populations constitution and contribute to resume soil ecology.

Abstract:通过室内培养实验,应用δ~(13)C方法研究了玉米秸秆分解期间,土壤固有及新形成有机质的分解转化规律。结果表明:玉米秸秆分解期间,土壤固有及新形成的有机质都逐渐分解,但前者的分解速度较慢。第360 d时,玉米秸秆和土壤固有有机质的残留率分别为30.0％和92.2％;720 d时分别为25.3％和78.8％。培养初期,富里酸的形成速度大于胡敏酸,而后富里酸转化为胡敏酸或相互转化;与新形成有机质相比,固有有机质中胡敏酸、富里酸的转化速度相对较慢。

Abstract:用传统统计和地统计方法相结合，对甘肃省武威及张掖灌漠土耕层土壤有效B，Cu，Fe，Mn及Zn等微量元素的空间变异特征进行了研究。结果表明：武威土壤有效Zn和Fe普遍缺乏，张掖土壤除Zn较缺乏外，其余元素均较充足。描述性统计结果显示不同土壤微量元素的变异程度各不相同。地统计分析结果表明，武威和张掖土壤微量元素空间分布的最大相关距分别在192～477m及141～206m之间；武威土壤中除有效B含量具有中等的空间自相关性外，其余微量元素及张掖土壤所有微量元素均具有强烈的空间自相关性。武威和张掖土壤微量元素分布的分形维数变化范围分别为1．804～1．947及1．945～1．987，其中武威土壤有效B的最低，并具有中等变异程度，其空间变异主要由施肥、作物、管理水平等人为因素引起。其余微量元素及张掖灌漠土微量元素含量的空间分布强烈自相关，其变异主要由土壤母质、地形、气候等非人为因素引起。且张掖土壤中微量元素的空间自相关性比武威的强烈，即包括人为活动在内的表生作用对该土壤微量元素分布的影响较弱。

Abstract:The effects of various kinds of inorganic acids on the content,cation exchange capacity and optics nature of humic acid in brown coal were studied. The content and the optics nature were not affected by phosphoric acid and hydrochloric acid treatment,but can be increased the exchange capacity to some extent. The content of humic acid can be increased by 25 per by suitable for intensity nitric acid, The cation exchange capacity can be greatly in- creased and the optics characteristic was greatly changed. The best condition would be different to different brown coal.

Abstract:With soil-resin-core equipment, the difference of NO~-_3-N leaching in soil and its correlation with four aspects including the content of NO~-_3-N, the content of available N, rainfall and temperature were studied. The results were shown as follows: The NO~-_3-N leaching in acid purple soil was the highest, while it was lower in yellow soil and alkaline purple soil. Both the content of NO~-_3-N and available N were correlated positively with NO~-_3-N leaching in acid purple soil. The content of NO~-_3-N and available N were not interrelated with the NO~-_3-N leaching in yellow soil and alkaline purple soil. Rainfall and temperature were also primary factors which affected NO~-_3-N leaching. Fertilization rates, fertilization times, rainfall and temperature could result in together groundwater pollution. To control fertilizer rates, to reduce manure application and to avoid fertilizing in heavy rainfall were the effective ways to control nitrate nitrogen leaching.

Abstract:The rainfall, runoff, soil content in water on the hilly area of the central Sichuan basin have been stud- ied in paper, debited the mathematic mode forecasting the sand and soil eroding. There has been analyzed connec- tion to the differing forests types with by the numbers and synthetically. What's more, parallel synthesis the law of the loss about the sand and soil. It is studying the sand and soil loss that make protect the sand and soil on the hilly area of the central Sichuan basin, so the law can help farmers to change the protect forests in the future.

Abstract:通过采集39个样本,调查研究了重庆市1998～2002年化肥使用与残留的分布特征。重庆市化肥全年使用水平为317.08 km/hm~2,高于全国平均水平。都市发达圈水平最高达758.24 km/hm~2,是渝西走廊的2倍。按施肥量水平则分为高施肥量区、中施肥量区、低施肥量区。施肥量水平与粮食产出、种植业经济产出呈明显的负相关性,施肥量越高,其投入效率越低,呈现出明显的报酬递减规律。化肥当季使用水平(x)与粮食产量(y)之间的关系为一抛物线方程。化肥平均利用率为35.72％,其中高施肥量区域最低,只有32.33％,低施肥量区域则达到49.12％。化肥使用总体上基本平衡,但过量使用、基本平衡和可增加使用的区县分别有9,13,17个。都市发达圈为化肥过量使用,渝西走廊与三峡库区为基本平衡。化肥残留总量最高的是三峡库区,每年进入三峡库区重庆段的氮肥约为10.31×10~3t/a,磷肥13.60×10~3t/a,严重影响了三峡水库水质。直辖后化肥当季使用水平和全年使用水平分别减少18.83％,43.28％,单位化肥的粮食产出减少28.35％,化肥利用率减少31.78％,但单位化肥的种植业经济产出增加80.93％。

Abstract:China has carried out the strategy of western region exploitation since 1997. More and more organiza- tions and people started to care of the eco-environmental issues in western China again. The plan aimed at moni- toring the eco-environmental change in western region with remote sensing over the period of 1990 to 2000 and supplied scientific decision-making for national strategy of western region exploitation. The study selected 7 typi- cal sites in western region in first stage, adopted the methodology of integrated remote sensing and GIS technolo- gy, laid a guide to eco-environment monitoring with remote sensing to dynamic monitoring eco-environment change in these regions from 1990 to 2000 according to 8 uniform rules. The results show the land for agriculture and city construction increased with occupying the land for natural and semi natural vegetation. And the regions are subject to the developing trend of eco-environment degradation.

Abstract:The 11 types of soils were selected from all of 17 types of soils in Shaanxi according to the distributing area and the representative. We have gather about 159 soil samples from all the province. The result of analysis showed that the average content of available silicon in soils in Shaanxi Province is about 390. 99 mg/kg, the high- est 980. 32 mg/kg, The lowest 74. 5 mg/kg. The variational tendency of content of available silicon in soils in- creases from the north to the south and decreases from the east to the west. The content of available silicon is di- rect correlation to organic matter, total nitrogen,total phosphorus in soil, is irrelevant to total potassium in soil in the south of Shaanxi.

Abstract:Besed on the investigation and sampling analysis of runoff and nutrient under six land utilization forms, resu1ts showed that the majority of soil nutrients was removed with runoff and sediment. The runoff quantities and nutrient loss quantities under different land utilization forms had obvious imparity. Two kinds intercropping or- chard-pasturage increased antierodibility so as to raise the soil productivity. The sediment concentrated the lost nu- trient of runoff.

Abstract:Since the 20th century , research on forest and slope-runoff yield has achieved a great progress, especial- ly in China are deeper and wider. Observation experiments are still the absolute predominance. Runoff plot experi- ments are adopted widely. Forest has influence on the slope-runoff yieldmechanism, slope runoff flow pattern, runoff yield amount, yield process, yield rainfall critical value, surface runoff and underground runoff division, and the impacts of litters on slope-runoff yield. In addition, slope-runoff model has been applied in forest hydrolo- gy.

Abstract:以研究植物根系密度、根量及根层土壤剖面特征为基础,以退耕自然生草地和农耕地(横坡玉米 红薯)为对照,对两种果草模式根系提高土壤抗蚀性进行了定量研究。结果表明:土壤的抗蚀性与土体中根系含量密切相关,两种果草模式的根系总长度、根系表面积和根系总生物量都要明显高于自然生草地,而且这些根系指标与土壤抗蚀性呈正相关变化,这与水稳性团聚体和有机质含量与土壤抗蚀性呈正相关变化的趋势一致;果草模式土壤抗分散的能力得到了相当程度的改善,颗粒间团聚程度有了明显提高,土壤团粒结构得到了一定程度的改良;在南沱镇紫色土坡地发展的果草示范模式,其根系明显地提高了土壤的抗蚀性,可以在三峡库区范围内推广。

Abstract:Field Scouring Experiment on the residues of shenfu dongdheng coalfield during exploitation was con- ducted with the method of simulate overland flow. Results showed that the shorter deposits time of the residues characterized the larger erodibility due to the gradually stable compaction after 4 to 7 years natural deposit process. Sediment load decreased with the order of residues of 1997 , residues of 1994, coal and gangue under the same overland flow. Moreover, linear relation lies in runoff, sediment and overland flow. Sediment concentration in mining-site residues kept a high level and turned irregularly with time, which revealed high erosion potential in these sites. It decreased and approached to a constant in the last. In addition , debris flow goes with the runoff and sediment processes.

Abstract:The efficiency of rainwater harvesting utilization plays an importantrole in a small rain-fed agricultural valley. With the Ankou Valley in Shandong Province as a study area, firstly, the influence of the soil infiltration on the rainwater collecting in a certain area was elucidated, rainwater harvesting efficiency was estimated by runoff coefficient method in hydrology. The experiment shows that the soil stabilization infiltration is less than normal, but the average runoff coefficient is 0. 46, higher than in Loess Plateau. So in such valley, it is much more advantage to develop rain-fed agriculture using the natural valley runoff area to collect rainwater.

Abstract:Integrated Geographical Information System(GIS) with Universal Soil Loss Equation(USLE),soil loss was predicted and risk areas of soil erosion were identified in Jiulong river watershed. Reasonable methods were adopted to obtain R, LS , K , C, P factors value. Results showed annual average soil erosion amount was 2 730. 3 t/ km~2 and it was in the category of middle degree erosion. The serious eroded area(sediment yield is higher than 5 000 t/km~2) only occupied 14. 28% of area, but contributed 41. 74 % of sediments in the watershed , while no or slightly eroded area(sediment yield is lower than 5 000 t/km~2) was 85. 72% of area, but contributed 58. 26% of sediments. The annual average soil erosion was higher in Chuanchang river, Huashan river, and Yanshi river sub- watersheds. The annual average soil erosion was lower in Longhai and Punan segment in North river sub-water- sheds.

Abstract:Using the theory of restoration ecology, and regarding the sustainable development of region as the main object, combineing with the present condition of withdrawing from farming to afforesting and grass planting in the middle and lower reaches of Tarim river, this put forward the evaluation index system and evaluation model of compositive ecological benefit of ecological project of withdrawing from farming to afforesting and grass planting in the middle and lower reaches of Tarim river. The evaluation index system includes 11 indices relating to biologi- cal benefit, soil benefit, small climate benefit and hydrological benefit. Applying analytic hierarchy process (AHP) evaluated ecological benefit of ecological forest, economic forest and herbage grassland and also compared with farmland ecosystem. The result indicated that compositive ecological benefit index of ecological forest 9 eco- nomic forest and herbage grassland ecosystem larger than farmland ecosystem and the order of ecological benefit is economic forest>ecological forest>herbage grassland>farmland ecosystem. Therefore the paper proposes some scientific suggestion of planning, overall arrangement, sort of tree and grass of ecological project withdrawing from farming to afforesting and grass planting in the middle and lower reaches of Tarim River.

Abstract:通过对15°红壤坡地11个利用模式10年土壤侵蚀研究,认为红壤坡地土地利用模式中林作系统水土保持效果优于农作系统。林作系统中水土保持效果以常绿阔叶林最好,次为混交林,毛竹林和针叶林。农作系统中顺坡植物篱种植、等高梯化种植、顺坡水平沟种植水土保持效果较好。研究认为红壤坡地土地利用模式应以林作为主,尽可能发展高效的经济林。而如发展农业种植,则以顺坡植物篱种植模式最佳,次为等高梯化种植模式。

Abstract:The text summarizes the study on functions of water and soil conservation for 3 control models and the contrast in heavily corroded region in Shuicheng County, locating in west part of Guizhou. The result showed that the rank of function on water and soil conservation among 3 control models was pattern 3>pattern 2>pattern 1; their soil weights per unit reduced by 37. 6%, 21% and 26. 6% respectively comparing to the contrast; their amounts of holding water increased by 82 %, 43. 5 % and 61. 7% respectively comparing to the contrast; their ventilation degrees were 2. 26, 1. 44 and 1. 16 times of the contrast;s respectively; and the strengths of anti-ero- sion were 3. 16, 2. 67 and 2. 06 times of the contrastts respectively. Pattern 3 showed the best permeability of soil, the initial rate of infiltration and the stable rate of infiltration were 1. 87 and 2. 10 times of the contrast's re- spectively, were 1. 05 and 1. 34 times of pattern 2's and 1. 45 and 1. 62 times of pattern 1's. In terms of the ability of holding water of doddered branches and leaves, pattern 3 had the strongest ability and the amount of holing water per hectare was 11. 07 tons, which was 1. 26 times of pattern 2's and 1. 98 times of pattern 1's respectively.

Abstract:Gully erosion holds an important position in soil erosion, and monitoring the gully erosion is the major part of the study of gully erosion. Photogrammetry is mostly used in the study of monitoring gully erosion cur- rently, however, the method has limitations to some extent. This article the study of gully erosion using GPS was discussed by surveying the gully at different time, constructing the DEMs, and comparing the DEMs, the changes of the gully can be obtained. At the last part of the article, a case study of a gully at Fengchan Catch- ment, Heilongjiang Province is presented, the DEMs with resolution of 0. 4 m were constructed, and the dynamic changes of the gully between October 2002 and October 2003 were obtained, it shows that the gully retreated 13. 78 m, the erosion area expanded 711 m~2, and the erosion volume was 2 377 m~3. The case study exposes the ad- vantages of GPS survey in monitoring the gully erosion, and provides an alternative approach to monitoring the gully erosion.

Abstract:The ecological environment of dry-hot valley in Jinsha River, where landslide and debris flow mountain hazards have frequently occurred, and with heavy soil and water loss, is very fragile. In this paper, the vegetation rehabilitation techniques and ecological effects in the Xiaojiang Basin are studied. Based on different site conditions and plants biological characteristics, seven rehabilitation measures are set up in the dry-hot valley. The results of ecological effects, which are studied by artificial rainfall and contrasting method, indicated that: the vegetation e- cological effects are very good in staying water and soil and improving soil infiltration function. In bare land, bare trees and herbs land, shrubs and herbs land, the time of bringing surface runoff is 31, 34, 75 min after artificial rainfall respectively, and the time of stable surface runoff ratio is 61, 79, 150 min respectively. The ration of stable runoff is 6. 20, 3. 04, 0. 64 L/ min respectively. The average ratio of sediment is 6. 8, 4. 2, 2. 0 g/L respectively.

Abstract:Through making field investigation and using the results of 2000 TM images classified, the distribution patterns and development trend of land sandy desertification as well as its causing negative affection were analyzed in this paper. In the view of the spatial distribution and temporal variation of climatic factors and the relation be- tween mankind and earth, the driven factors of occurrence and development of land sandy desertification was ex- plored. The results showed that the spatial distribution of land desertification was different with the scope of the wind erosion climatic factor in spring; that the development rate of land sandy desertification disagreed with the variation of three main climatie factors. The final conclusion drew is that the main reason of land sandy desertifica- tion in study area in the last 50 years isn't the temporal and spatial variation of climatic factors. The real reasons are the serious unbalance between the pressure coming from man and livestock and the environmental capacity; the worse management on the relation between human and land; the unenlightened and extensive produetion and living styles.

Abstract:湘北红壤坡地土壤持水力强,有效水含量低(10％左右),含水量呈季节性变化(年变化可分为饱和、亏缺和补充3个时期);土壤结构性差,养分贫乏,原始生产力低,易产生降雨土壤侵蚀。湘北红壤坡地雨水自然资源化程度为降雨量的(46±2)％,农业利用中必须强化雨水资源化过程。坡地典型农业利用系统(旱季)地表/大气界面的水分传输表现为:植被构成是影响传输通量的第一要素;气温和界面水势是影响土/气界面水分传输的主导环境气象因子;辐射和空气饱和水气压差是影响叶/气界面水分传输的主导环境气象因子;在一定的土壤含水量范围内,土/气界面水分传输通量受表层土壤含水量控制。土壤水分变化影响能量平衡,土壤蒸发量与土壤表层水分含量之间有线性正相关;土壤水分除通过影响能量分配来影响植物蒸腾外,土壤水分还能通过影响叶片气孔导度来影响植物蒸腾速率。

Abstract:对2003年6～10月羊草草地和大豆地的盐渍化特征(含水量、pH值和含盐量)的动态变化进行分析，并对比2种土地覆被类型之间的变化差异，结果发现：羊草草地和大豆地含水量变化与采样区降雨量的变化有相同趋势，但在采样初期和末期，大豆地含水量要大于羊草草地；对于pH值和含盐量，在土壤剖面0～60cm，两种覆被类型不同层次动态变化一致，大豆地变化的一致性可达到更深层次，但是其峰值要比羊草草地滞后20天左右出现，同时2种土地覆被类型pH值和含盐量的峰值均滞后于含水量的峰值。单因素方差分析表明采样期内2种土地覆被含水量在剖面40～80cm差异显著，而pH值则是在整个剖面都有显著差异，含盐量在20～60cm剖面深度差异显著。2种覆被类型各个剖面深度10月17日的pH值、含水量比6月7日有所上升，含盐量则刚好相反。

Abstract:通过将沙棘与小黑杨和欧美杨64号的人工林分别按株混和行混2种方式进行混交实验,研究了固氮植物沙棘对辽宁西部杨树人工林土壤水分动态变化的影响。研究结果表明:(1)在0～20 cm的表层土壤中,混交林的含水量均显著高于各自纯林的含水量(p<0.01),20～120 cm的深层土壤中,混交林的土壤含水量整体趋势表现为显著低于各自纯林中的土壤含水量,只有8月处理Ⅰ纯林和混交林的土壤含水量没有显著差别;(2)2000年6,8,9月,同一人工林两两月份间的土壤含水量均有明显差别,土壤含水量大小顺序都是8月>9月>6月,不同月份间土壤含水量的差异大小随土壤深度、杨树品种、混交方式的变化而变化;(3)杨树人工林不同土层含水量与天然降水之间有明显的相关性(r~2>0.90),天然降水是杨树与沙棘混交林及杨树纯林土壤水分的主要来源。

Abstract:为了评价人工林下凋落物与土壤截留降水的能力,定位监测和分析了岷江上游23年生人工油松纯林下凋落物层和土壤层对65次降水事件的截留与分配过程。结果表明,65次林外降水总量为400.9 mm,其中208.726mm以穿透雨、33.388 mm以树干茎流进入林地,凋落物层、土壤层分别截留25.695,214.375 mm,截留率分别是6.41％,53.47％。但林外降水量<0.3 mm时,不产生林内降水,凋落物与土壤层不能截留降水。在0.3～10 mm降水范围内,土壤截留量随着降水增大呈增加趋势,而凋落物层截留率先增后减,但降水量>10 mm后,土壤截留率逐渐趋于稳定,呈较小波动(63.46％～73.58％),而凋落物截留率趋于稳定,并略有下降趋势;土壤截留量与林内外降水量、土壤截留量与茎流量均呈显著线性相关关系。综合分析表明,人工油松林凋落物层和土壤层对降水均有一定的拦蓄截留效应,其中:土壤层>凋落物层,土壤层的截留量达同期林外降水量的1/2以上。

Abstract:The vegetation restoration and construction on the Loess Plateau is a key ecological engineering in Chi- na. It is extremely important for the improvement of local ecological environments and economy. There are many problems in vegetation restoration and construction on the Loess Plateau, although we have practiced this over fifty years. In order to get obvious efficiency from the vegetation restoration and construction, the theory and techniques are discussed in detail in this work. We hope that these theory and techniques can be applied to the practice of vegetation restoration and construction, and obviously improve its results.

Abstract:The changes in land use patterns of Zhifanggou Catchment located in loess hilly region on the Loess plateau were studied using land use maps (1: 7000) derived from the aerial photos and field survey data. The re- sults showed that changes in land use pattern are closely related to human activities. The expansion of agricultural land use was the main reason for the destruction of vegetation and land use pattern change. From 1938 to 1958, the dominance index of vegetation decreased from 55. 94% to 0. 44% while the dominance index of slopping farm- land increased from 12. 65 % to 56. 05 %. After 1958, the vegetation restoration had seen a very slow period (from 1958 to 1973) and a rapid period (after 1973 ) with the changes in agricultural land uses. During this pro- cess, there are two critical points, 1958 and 1995, marked fundamental change of the landscape matrix as well as ecological environment. The study also showed that the landscape shape index was closely related to the intensity of human disturbance; the landscape diversity index was similar in 1938 and 1958, and increased gradually from l975 , and reached the highest level in 1995, then decreased again due to the conversion of slopping farmland to forest and grass. The land use pattern dominated by one land use type has been changed to a new one dominated by several land use types, mainly resulted from comprehensive management carried out in this catchment since 1973.

Abstract:Using the Landsat TM data in the years of 1997 and 2002, the land cover map has been made respec- tively in sample areas locating in Zhangjiakou, Yulin and Dngxi, and then analyzed the effect of National Key Project of Ecological Environment Construction and the changed characteristics of land cover landscape according to the transformed acreage of land cover types and landscape indices. The results showed that a serious of con- struction measures in practicing, such as, returning farmland to forestland or grassland, have an effect on the amelioration of ecological environment. As the difference of climatic and economic conditions in different sample areas, it is easier to carry out the Project and to achieve more successful result in Zhangjiakou sample area than in Yulin and Dngxi's. The land cover change of all sample areas characterized by farmland decreasing, natural or semi-natural vegetation increasing, and the reducing of irregularity of patch shape of them. On the landscape scale, the complexity of patch shape and the variety of landscape all has decreased.

Abstract:As a fragile factor of karst ecosystem, karst underground water system is highly sensitive to landuse change. Taking Houzhai subterranean stream basin, Puding County, Guizhou Province as an example. The im- pacts of intensity of agriculture activities, landuse change and irrigation system change upon underground water were analyzed based on more than 20 years' hydrochemical data. The results showed that both intensification of a- griculture activities, landuse change and irrigation system change can bring spatial and temporal change of under- ground water quality. Some are beneficial, such as co-irrigation of ground and underground reservoirs, vegetation planting(from farmland to forest); others are disbeneficial, such as urbanization, direct discharge of waste, and overuse of pesticide and fertilizer. Accordingly, underground water vulnerability should be considered during the landuse planning, thus help the harmonious development between human activities and resources and environ- ment.

Abstract:The typical natural landscapes and temporal-spatial regulation of land use change and their ecological ef- fects at Hailun County were conducted and analyzed, based on the translated data from remote sensing images in 1986 and 2000 using GIS and landscape ecological theory. The results indicated the area of arable land, paddy field and city land increased 7 786. 39, 3 391. 18 hm~2 and 120. 84 hm~2 while the area of forestry, grassland and marsh decreased 3 184. 88, 1 625. 8 hm~2 and 3 994. 85 hm~2 respectively during 14 years. Dry land is a main land- scape in this area. These changes made the environmental quality worse gradually, such as land degradation, soil erosion and water and soil losses, and temperature getting warmer. This study is very important for the local eco- logical environment protection and agricultural sustainability and land resources sustainable using.

Abstract:The physical property of karst mountain desertification soil under different land use in Chongqing Beipei karst mountain was studied. The result shows that when the nature forest land is replaced by grass land,artificial land, vegetable land and plantation gradually, the land is becoming more arenaceous and the soil bulk density in- creases, and the total percentage of pore, especial the percentage of non-pore increase greatly. Although the ag- gregate structure measured by dry sieve are quiet similar under different land use, the water-stable aggregate structure got by dump sieve is quite different. The destroy of aggregate structure is high. With the vegetable land and plantation changed into deserted land, all physical standards are improved. On the basis of those studies, the author briefly analyzed the correlation between the degrading soil physical feature and the desertification, and pos- sibility of reducing the soil erosion by deserting land.

Abstract:Taking the Liudaogou watershed which is located in Shenmu County, Shaanxi Province as the exam- ple, based on the landscape quantitative calculating method and the Markov transforming matrix, the spatio-tem- poral change of landuse/cover at the different period was discussed. The steps were following: first of all, to digi- tize the three landuse maps and unified the coordinate of these maps; secondly, to chose the suitable landscape quantitative indicators and next, calculated them under the statistic software, at last, to analyze the trend of spa- tio-temporal change from different landuse/covers. The results would provide the scientific support for rational us- es of soil resources, land use plan and soil and water controlling in Loess wind-water erosion crisscross region.

Abstract:Based on the TM image of Wuwei and Minqin oases in middle and lower reaches of Shiyang rivver in 1986 and 2000. Using GIS technique and landscape structure analysis program FRAGSTATES. It calculated and analyzed the landscape metrics and their changes of studying regiong at class metrics level and landscape metrics level respectively. And also the changes of land use patterns in two oases were compared by caculatin transforma- tion matrixes of landscape mosaics.

Abstract:Fractal dimension values of each landscape of the mosaic structure of land use and land cover are calcu- lated at Wenchuan county in Sichuan province. Properties of fractal dimension of each landscape and their changes are discussed. It is indicated that the mosaic structure of land use and land cover has statistical self-similarity and its fractal dimension value is a kind of random fractal geometry by the research. Bigger fractal dimension value in- dicates that the spatial configuration of a landscape is more complex, whereas its spatial configuration is simpler. The stability index of a landscape bigger than zero means that the stability of landscape spatial configuration under complex state. The bigger the value of SI is, the more stable.the spatial configuration of a landscape is vice verse. The stability index of a landscape smaller than zero means that the stability of landscape spatial configuration un- der simple state. The smaller the value of SI is, the more stable the spatial configuration of a landscape is; vice verse. The spatial configuration of a landscape gets more and more complex if the fractal dimension value increases with time, whereas its spatial configuration gets simpler and simpler. The quantity fractal dimension is a compre- hensive index to study landscape pattern of the mosaic structure of land use and land cover.

Abstract:采用Li—6200光合分析仪,对祁连园柏和青海云杉两种针叶树种的光合速率进行了日变化和季节变化测试,结果表明:祁连园柏和青海云杉两种针叶树种的光合速率日变化均呈单峰曲线,两种树种的光合速率日变化峰值均出现在1日之中的9:00时,其中青海云杉光合速率日变化峰值为9.06μmol/(m~2·s)祁连园柏光合速率日变化峰值是7.154μmol/(m~2·s)。两种树种光合速率在季节变化中青海云杉有两个峰值分别在5月和8月分别为3.124,3.497μmol/(m~2·s);而祁连园柏的光合速率在季节变化中只有一个高峰值在5月份,为2.96μmol/(m~2·s)。两种树种的光合速率及其内外影响因子相关分析得出:青海云杉Pn与RH、COND两因子之间呈极显著正相关关系(r=0.632 6与r=0.688 4);与CINT、RS因子呈极显著负相关关系(r=-0.4620与r=-0.5740)。祁连园柏Pn与RH因子呈极显著正相关关系(r=0.412 6);与其它因子呈不显著正或负相关关系。两种针叶树种的WUE在生长季节变换中,青海云杉WUE较高值在5月和8月分别为0.636 98和0.532 4,平均WUE是0.315 6;祁连园柏水分利用效率WUE较高值在5月和6月分别为0.263 1和0.280 5,平均WUE是0.132 8。

Abstract:应用环境经济学原理与方法研究了北京山区水利富民工程改善生态环境和促进社会发展的价值。研究结果表明,工程的生态环境价值为1148.5亿元,包括保护水资源的价值735.7亿元,保护土地资源的价值70.6亿元,保护环境的价值44.8亿元,生态旅游价值297.3亿元。其中,水利工程产生的价值是459.4亿元,占总价值的40％。社会效益价值体现在招商引资7.24亿元,农民人均纯收入增长了55.5％,北京山区教育事业费和中级以上科技人员总数分别增长了32.8％和4.5％。

Abstract:Based on the analysis of district soil and water loss influence factors, the index system of soil and water loss sensitivity evaluation was established. By means of the function of spatial analysis of GIS, the spatial dis- tribute of different grade on realistic sensitivity and potential sensitivity to soil and water loss in Shaanxi province were identified. The result of potential sensitivity indicates that tioy-less sensitive region took up 75. 77% of the total area of the province, the sensitive region 20. 41 %, and the more-most sensitive region 3. 82%. The district separate regulation of sensitivity is very obviously , and the affect factors were not same alike. The result of realistic sensitivity shows that tioy-less sensitive region took up 61. 65%,the sensitive region increased obviously, which cover 34. 15% of the total study area, more-most sensitive area also increased ) which cover 4. 2% of the total study area. The difference between realistic sensitivity and potential sensitivity was compared in this study, due to the nature factors was not easi1y control, increasing vegetation cover to control the soil and water loss has special important meaning.

Abstract:According to the character of saline-land of desert area of Hexi Corridor, a control desertification model of integrated fixing, closing, defending was made up by method of fixed moving sand by sandy barrier, closed for raising vegetation, making up defending belt and establishing wind break belt. In saline land, an improving saline- land model of developing, cropping and bred was raised by physical improved method, cultivated saline-resistant plant and breeding livestock for fertilizing land. By above mentions, an ecological and economical benefit was obvi- ously taken on integrated developing saline land of desert zone.

Abstract:Eco-environment evaluation index system includes many indexes,and the result of evaluation should re- flect the spatial pattern of regional eco-environment. In order to analyze and evalute eco-environment in Hunan province,this research used the combination of geographical information system(GIS) with AHP. The mathemat- ical methodology for study on eco-environment was explored and developed. This research focused on the analysis of eco-environment in Hunan province. Firstly,this paper set up the eco-evironment indexes system based on the eco-evironmental characteristic of Hunan province. Secondly,calaculating the weight of each selected indexes and the value of each evluation cell by AHP. Finally,got the synthetic eco-environment evaluation result map of Hu- nan province by GIS. It found that eco-environmental quality of Hunan province decreases from east to west. With exception in a few areas, the spatial pattern of society economic and eco-environment is consistent with that of natural environment. It indicates that natural factors determine the spatial pattern of eco-environment of Hunan province. However,some other factors also affect the eco-environment and influence its spatial pattern in some cases,such disasters, pollution and society and economic.

Abstract:Land consolidation targets include many aspects and many levels. Especially, there is different target of land consolldation in different regions. Methods of documentation and induction are employed in this study. Based on analyzing the regional allocation of land consolidation target , according to the differences among three economy regions of Chongqing, target and keystone of land consolidation in different regions were suggested. In the city- developed circle serving food security and economy security, more attention should be paid to agricultural land con- solidation and non-agricultural land consolidation associated with the adjustment of agricultural structure. In the Yuxi economy corridor serving food security, resources security and ecological safety, in order to ameliorate yield- ing and ecological condition, it is necessary to strengthen integrative controls, constructing central rural settlement and reclaiming mining and project land. In the three Gorges ecology and economy circle severing resources security and ecological safety, land consolidation should not only emphasize return of cultivate land to woodland and grass- land as well as low-effect forest, garden and grassland reconstruction, but reclaim damage and waste land as well as middle-low yield soils, combining with control of watershed.

Abstract:The main performance of grassland degeneration was that the components of grassland became bad, its productivity decreased, the usable grassland reduced and its environment deteriorated in Two West Region. Be- cause of the climate change ) the special terrain in loess plateau, the pest ) disease and mouse in grassland degenera- tion, industry limitation, and management problem and the influence of different situation and micro-biology, the fragility of grassland environment, barren soil and low utilization rate were caused. The principles of managing the degraded grassland were the industrialization of ecological construction, the combination of adjusting measures to local conditions and systematic management, the heavy recovery-medium protection-light utilization and continuity of policy. While its goal was to build the mountain-oasis-desert coupling system in Hexi Region and participate in the construction of Loess Plateau Great Animal Husbandry Base in Dingxi Region respectively. Two regions could be integrated to the coupling system of the irrigated agricultural region and the rainfeed agricultural region.

Abstract:Water resources assessment is the base of water resources use. The research progress is summarized and some questions of water resources are brought forward. At last, the four important questions of water resources calculation in the main channel region, water quality and water quantity integrated assessment, influence of hu- man activities on water resources and ecological water needed are discussed. These shall improve water resources assessment.

Abstract:According to the investigation of resource status and exploitation condition of Qinghai Salt Lake, exist- ing problem was concluded and the index system of estimating sustainable development of Qinghai Salt Lake re- source was found out well. The level of exploitation of Qinghai Salt Lake resource was tentatively defined as that it is still in the preliminary stage of sustainable development.

Abstract:The Geodatabase model was introduceed, using the Object-Oriented method and UML designs non- point source pollution spatial database of the Three-Gorge Region based on Geodatabase. The result indicates that the Object-Oriented method can do well in designing the spatial database by using Geodatabase model.