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Science china Earth sciences 2008年第6期51卷 862-870页

作者： ZHU YuanJun1,2 & SHAO MingAn1 1 institute of Soil and Water Conservation, chinese academy of sciences and Ministry of Water resources, Northwest Agriculture and Forestry University, Yangling 712100, china 2 institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china 1. institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Northwest Agriculture and Forestry University Yangling 712100 China 2. institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China

The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess Plateau. The results indicated that the maximal cover of rock fragment was pre-sented at mid-position in steep hillslope. Rock fragment presented a general decreasing-trend along the hillslope in gentle hillslope. Rock fragment cover was positively related to gradient, rock fragment size decreased generally along the hillslope, and the size reduced with the gradient. The mean size of rock fragment was at a range of 6―20 mm in the steep hillslope, rock fragment size > 50 mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment 2―50 mm accounted for 60% or more of the total area, dominating the distribution of rock fragment in the hillslopes.

关键词： wind-water erosion crisscross region of the Loess Plateau small catchment hillslope surface rock fragment cover and size

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science china Earth sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2, LI Xiubin2 & ZHANG Ming2 1. institute of Remote Sensing & GIS, Peking University, beijing 100871, china 2. institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china 1. institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. institute of geographical sciences and natural resources research Chinese Academy of Sciences 100101 Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 20%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

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Science china Earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2 1. institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking University, beijing 100871, china 1. institute of geographical sciences and natural resources research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium

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Science china Earth sciences 2005年第4期48卷 521-529页

作者： LIU Xiaohong1,2, QIN Dahe1, SHAO Xuemei , CHEN Tuo1 & REN Jiawen12 1. Cold and Arid Regions Environmental and Engineering research institute, chinese academy of sciences, Lanzhou 730000, china 2. institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china 1. Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences 730000 Lanzhou China 2. institute of geographical sciences and natural resources research Chinese Academy of Sciences 100101 Beijing China

Based on the cross-dated tree-ring samples collected from the middle Qilian Moun- tain, a standard ring-width chronology had been developed, which covered the period AD 1000 to 2000. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the “Little Ice Age” and the con- tinuous warming during the twentieth century. Comparison between the ring-width chronology and δ18O records from the Dunde ice core in the Qilian Mountain indicated that there was a con- sistent trend in both time series. A significant correlation existed between our ring-width chro- nology and the Northern Hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global cli- mate.

关键词： middle Qilian Mountain, tree-ring width chronology, temperature variations.

Floating Population Increase and Its Influence on the Urban Population Situation:A Case Study in beijing

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chinese Journal of Population,resources and Environment 2005年第1期3卷 27-35页

作者： Wu Peilin 1,2 & Lu Qi 2 1. Shandong University of Technology, Zibo Shandong 255049, china 2. institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china Shandong University of Technology Zibo Shandong 255049 China institute of geographical sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China

Floating population is a special population group in china resulting from the implementation of household registration system. This paper uses a set of floating population survey data, population censuses data and statistical data to analyze the increase and influence of floating population on the urban population situations in beijing. It is found that beijing has experienced a rapid increase of floating population since the 1990s and that the increase of this group has become the key factor of the current population expansion in the city. Its distribution in the urban regions intensified and extended the suburbanization process of the capital. In addition, the population structures of sex, age, education and employment in beijing have changed to some extent due to the influx of floating population.

关键词： Floating population Household registration system (Hukou) Population expansion Suburbanization Population structure beijing

基于地貌演进背景的流域自然与人为侵蚀定量评估——以鲁中南山地为例

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山地学报 2005年第4期23卷 4462-4468页

作者：姜鲁光赵慧霞张祖陆中国科学院地理科学与资源研究所山东师范大学人口.资源与环境学院北京100101 中国科学院研究生院北京100039 山东济南250014

在GIS软件的支持下,计算了鲁中南山地及其各流域的高程积分并判定了其地貌侵蚀阶段,对鲁中南山地第四纪平均侵蚀量作了初步估算。通过侵蚀指数、自然侵蚀指数、人为侵蚀指数等指标的构建,计算了鲁中南山地各流域水土流失的自然侵蚀背景... 详细信息

在GIS软件的支持下,计算了鲁中南山地及其各流域的高程积分并判定了其地貌侵蚀阶段,对鲁中南山地第四纪平均侵蚀量作了初步估算。通过侵蚀指数、自然侵蚀指数、人为侵蚀指数等指标的构建,计算了鲁中南山地各流域水土流失的自然侵蚀背景,进而得出人为侵蚀强度的流域差异。研究表明,鲁中南山地整体的自然侵蚀速率约为0.17 mm/a,大致相当于实际侵蚀的1/4,人为侵蚀强度较大;自然侵蚀强烈的流域主要分布在研究区北部,而人为侵蚀严重的流域主要分布在研究区东南部。提出了地貌演进背景下水土流失自然(地貌)侵蚀与人为侵蚀定量评估的技术方案,对鲁中南山地水土保持工作的政策措施提出了建议。

关键词：水土流失地貌发育自然侵蚀人为侵蚀鲁中南山地

TEMPORAL AND SPATIAL DYNAMICS OF DIFFERENT PARTICLE SIZE OF SUSPENDED SEDIMENT IN THE LIU RIVER CATCHMENTS, china

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International Journal of Sediment research 2006年第3期21卷 209-219页

作者： Haoming FAN1,2, Qiangguo CAI3, Chengjiu GUO4 and Tieliang WANG51 Lecturer, 3,4,5 Prof., College of Water Conservancy, Shen Yang Agriculture University, Shenyang 110161, china 2 Dr., institute of geographical sciences and natural resources research, chinese academy of sciences, beijing 100101, china College of Water Conservancy Shen Yang Agriculture University Shenyang 110161 China institute of geographical sciences and natural resources research Chinese Academy of SciencesBeijing 100101 China College of Water Conservancy Shen Yang Agriculture University Shenyang 110161 China

This paper presents information on the particle size characteristics of suspended sediment transported by the Liu River, which has the most serious erosion and sedimentation problems in the northeast of china. The median (d50) particle size for the individual stations on the Liu River ranged from 0.0343 to 0.0588 mm. Particles 0.05 mm of ranged from 24.3 to 53.7%. Spatial and temporal variations were noticeable in the particle size composition of suspended sediment within the study basins. At different locations the sediment particles size varies as a result of differences in catchment characteristics. The preferential deposition of the coarser size fractions has resulted in downstream fining of the suspended sediment load. In the flood season the suspended sediment particle size was finer than that in low flow season. The relations among water discharge, suspended sediment concentration, and sediment particle size are complicated. At small water discharge or suspended sediment concentration, with the increase of water discharge or sediment concentration the particle size of suspended sediment decreases to a minimum. However, when the water discharge or sediment concentration exceed certain threshold values (turning points) the particle size increases or remains constant with the increase of water discharge or sediment concentration. The tuning points are different in different rivers. Thus, their relations are double-valued. The negative relation between suspended sediment particle size and flow discharge reflects the importance of supply conditions and the positive relation reflects that the flow and hydraulics take a greater role in sediment transportation. On the whole, variation of the sediment particle size is subject to many factors such as the hydraulic conditions, the type and extent of erosion, human activities, vegetation coverage, hydraulic projects, and sediment supply. The findings reported in this paper have imp

关键词： Suspended sediment Temporal and spatial variation Particle size Liu River Catchment

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东北黑土区土壤侵蚀研究进展

水土保持研究 2007年第5期14卷 28-32页

作者：崔明蔡强国范昊明中国科学院陆地水循环与地表过程重点实验室中国科学院地理科学与资源研究所中国科学院研究生院北京100101 沈阳农业大学水利学院沈阳110161

东北黑土区是我国重要的商品粮基地,其粮食生产能力及可持续性关系到国家的粮食安全战略。近年来,日趋剧烈的水土流失,引起黑土功能的严重退化,引起了社会的广泛关注,各种调查和防治工作正在火热开展,所以我们需要对已有的工作进行全面... 详细信息

东北黑土区是我国重要的商品粮基地,其粮食生产能力及可持续性关系到国家的粮食安全战略。近年来,日趋剧烈的水土流失,引起黑土功能的严重退化,引起了社会的广泛关注,各种调查和防治工作正在火热开展,所以我们需要对已有的工作进行全面的总结,为以后的工作提供科学的依据。作者主要从黑土区土壤侵蚀的危害、影响因素以及侵蚀机理三个大的方面分别进行总结论述,希望对黑土区今后的土壤侵蚀研究工作提供一定的参考。

关键词：东北黑土区土壤侵蚀小流域侵蚀机理

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不同植被和土壤类型下土壤水分剖面的分异

水土保持研究 2011年第6期18卷 12-17页

作者：邹俊亮邵明安龚时慧西北农林科技大学资源环境学院陕西杨陵712100 中国科学院地理科学与资源研究所北京100101 中国科学院水土保持与生态环境研究中心黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨陵712100

为研究不同土壤类型下土壤水分的垂直分布特征及变异情况,在位于黄土高原水蚀风湿交错带的六道沟小流域选取坝淤土、黄绵土和风沙土3种土壤类型为研究对象,测定了0-600cm土壤水分含量,利用经典统计学方法进行分析。结果表明:坝淤土土壤... 详细信息

为研究不同土壤类型下土壤水分的垂直分布特征及变异情况,在位于黄土高原水蚀风湿交错带的六道沟小流域选取坝淤土、黄绵土和风沙土3种土壤类型为研究对象,测定了0-600cm土壤水分含量,利用经典统计学方法进行分析。结果表明:坝淤土土壤水分剖面呈有规律的波动型变化,黄绵土剖面土壤水分基本呈微弱的波动型变化,风沙土土壤水分剖面变化类型属于降低型;植被覆盖为柠条或小叶杨时,不同土壤类型对0-100cm间土壤水分含量影响不明显,而对100-600cm土壤水分含量影响显著(P坝淤土>风沙土,小叶杨覆盖下0-600cm平均土壤水分均呈现:风沙土>坝淤土>黄绵土;对3种土壤类型而言,同一土壤类型下植被类型的不同主要对深层土壤水分的垂直分布产生影响,总体上,农地和草地下的土壤水分状况好于灌木和乔木。这对于指导干旱区农业生产以及植被恢复中水分的合理调控具有积极的意义。

关键词：土壤类型土壤水分植被类型

Relationship between Environmental Pollution of Coal Mine and Spectral Characteristics of Nearby Plants

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Journal of University of Science and Technology beijing 2001年第1期8卷 10-14页

作者： Liqing Lei institute of Geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

Remote sensing technology, as the most advanced method for collecting data, along with the common ways often used in the past on research of environmental science, was integrated to study the relationship between environmental pollution of coal mine and spectral characteristics of nearby plants. With compositive index and mean reflectivity at near infrared, a regression equation was established, and a conclusion was made that spectral reflectivity can be used to distinguish regions with different pollution degree. Through testing with real status of the research region, it is verified that this kind of integration and conclusion not only are helpful for human being in controlling the movement law of pollutants and the corresponding change of coal mine environmental quality but also bring a new way for the research of environment problems of coal mine.

关键词： remote sensing spectral characteristics reflectivity pollution index compositive index atmospheric pollution