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Simulating Carbon Sequestration and GHGs Emissions in Abies fabric Forest on the Gongga mountains Using a Biogeochemical Process Model Forest-DNDC

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Journal of mountain Science 2008年第3期5卷 249-256页

作者： LU Xuyang CHENG Genwei XIAO Feipeng HUO Changfu institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of the chinese academy of sciences Beijing 100049 China

The process-oriented model Forest-DNDC describing biogeochemical cycling of C and N and GHGs （greenhouse gases） fluxes （CO2. NO and N2.） in forest ecosystems was applied to simulate carbon sequestration and GHGs emissions in Abies fabric forest of the Gongga mountains at southeastern edge of the Tibetan Plateau. The results indicated that the simulated gross primary production （GPP） of Abies fabric forest was strongly affected by temperature. The annual total GPP was 2.,2.5.3 kg C ha^-1 yr^-1 for 2.05 and 2.,318.8 kg C ha^-1 yr^-1 for 2.06, respectively. The annual total net primary production （NPP） was 5,935.5 and 4,882.2.kg C ha^-1 yr^-1 for 2.05 and 2.06, and the annual total net ecosystem production （NEP） was 4,815.4 and 3,512.8 kg C ha^-1 yr^-1 for 2.05 and 2.06, respectively. The simulated seasonal variation in CO2.emissions generally followed the seasonal variations in temperature and precipitation. The annual total CO2.emissions were 3,109.0 and 4,82..0 kg C ha^-1 yr^-1 for 2.05 and 2.06, the simulated annual total N2. emissions from forest soil were 1.47 and 1.36 kg N ha^-1 yr^-1 for 2.05 and 2.06, and the annual total NO emissions were 0.09 and o.12.kg N ha^-1 yr^-1 for 2.05 and 2.06, respectively.

关键词： Carbon sequestration Forest-DNDC GHGs Abiesfabric forest Gongga mountains

Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the sichuan Basin, china

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Journal of mountain Science 2008年第3期5卷 241-248页

作者： J.H. ZHANG Z.A. SU G.C. LIU Key Laboratory of mountain hazards and Earth Surface Processes Chinese Academy of Sciences 610041 China institute of mountain {2. and environment Chinese Academy of Sciences ＆Ministry of Water Conservancy Chengdu 610041 China The Graduate School of the chinese academy of sciences Beijing 100049 China

Soil erosion in hilly areas of the sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3-year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in Jianyang County, sichuan Province, Southwestern{2.. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2. is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3) regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 2..5～41.0 % and 2..5～69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (34.41～331.67 % and 37.06～403.44 % for Plot 1 and Plot 2. respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3-year experiments.

关键词： Agroforestry sediment transport runoff sloping terrace soil and water conservation

A study on water film in saturated sand

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International Journal of Sediment Research 2010年第3期25卷 221-232页

作者： LU X. B.1 and CUI P.2.1 Dr., Laboratory for Hydraulic and Ocean Engineering, institute of Mechanics, chinese academy of sciences, Beijing 100190,{2., 2.Prof., Key Laboratory for mountain Hazard and Earth Surface Process, institute of mountain Hazard and environment, chinese academy of sciences, chengdu 61004.,{2., Dr. Laboratory for Hydraulic and Ocean Engineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China Prof. Key Laboratory for Mountain Hazard and Earth Surface Process Institute of Mountain Hazard and Environment Chinese Academy of Sciences Chengdu 610041 China

Water film can serve as a sliding surface and cause landslides on gentle slopes. The development of "water film" in saturated sand is analyzed numerically and theoretically based on a quasi-three-phase model. It is shown that stable water films initiate and grow if the choking state (where the fluid velocity decreases to near zero) remains steady in a liquefied sand column. Discontinuity can occur in pore water velocity, grain velocity and pore pressure after the initiation of a water film. However, the discontinuity and water film can disappear once the choking state is changed. The key to the formation of water film is the choking in the sand column caused by eroded fine grains.

关键词： Saturated sand Water film Liquefaction

Response of Biomass Spatial Pattern of Alpine Vegetation to Climate Change in Permafrost Region of the Qinghai-Tibet Plateau,china

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Journal of mountain Science 2010年第4期7卷 301-314页

作者： ZHANG Yu WANG Genxu WANG Yibo College of Resources & environment Lanzhou UniversityLanzhou 730000China institute of mountain {2. and environment Chinese Academy of SciencesChengdu 610041China

Alpine ecosystems in permafrost region are extremely sensitive to climate *** determine spatial pattern variations in alpine meadow and alpine steppe biomass dynamics in the permafrost region of the Qinghai-Tibet Plateau,china,calibrated with historical datasets of above-ground biomass production within the permafrost region's two main ecosystems,an ecosystem-biomass model was developed by employing empirical spatialdistribution models of the study region's precipitation,air temperature and soil *** model was then successfully used to simulate the spatio-temporal variations in annual alpine ecosystem biomass production under climate *** a 0.44°C decade-1 rise in air temperature,the model predicted that the biomasses of alpine meadow and alpine steppe remained roughly the same if annual precipitation increased by 8 mm per decade-1,but the biomasses were decreased by 2.7% and 2.4%,respectively if precipitation was *** a 2.2.C decade-1 rise in air temperature coupled with a 12.mm decade-1 rise in precipitation,the model predicted that the biomass of alpine meadow was unchanged or slightly increased,while that of alpine steppe was increased by 5.2..However,in the absence of any rise in precipitation,the model predicted 6.8% and 4.6% declines in alpine meadow and alpine steppe biomasses,*** response of alpine steppe biomass to the rising air temperatures and precipitation was significantly lesser and greater,respectively than that of alpine meadow biomass.A better understanding of the difference in alpine ecosystem biomass production under climate change is greatly significant with respect to the influence of climate change on the carbon and water cycles in the permafrost regions of the Qinghai-Tibet Plateau.

关键词： Permafrost change Qinghai-TibetanPlateau Alpine ecosystem Grassland biomass Climate change Response model

Preliminary Study on Biological Characteristics of Degraded Soil Ecosystems in Dry Hot Valley of the Jinsha River

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Pedosphere 2002年第4期12卷 365-372页

作者： HEYURONG YANGWANQIN WANGKAIYUN SONGGUANGYU chengduinstituteofBiology theChineseAcademyofSciencesChengdu610041（China） CollegeofResourcesandenvironment SouthwestAgriculturalUniversityChongqing400716（China） instituteofmountain{2.andenvironment theChineseAcademyofSciencesandMinistryofWaterConservancyChengdu610041（China）

Distribution characteristics of soil animals, microorganisms and enzymatic activity were studied in the dry red soil and Vertisol ecosystems with different degradation degrees in the Yuanmou dry hot valley of the Jinsha River, china. Results showed that Hymenoptera, Araneae and Collembola were the dominant groups of soil animals in the plots studied. The numbers of groups and individuals and density of soil animals in the dry red soil series were higher than those in the Vertisol series, and the numbers of individuals and density of soil animals decreased with the degree of soil degradation. Bacteria dominated microbiocoenosis not only in the dry red soils but also in the Vertisols. Microbial numbers of the dry red soil series were higher than those of Vertisol series, and decreased with the degree of soil degradation. The activities of catalase, invertase, urease and alkaline phosphatase declined with the degradation degree and showed a significant decline with depth in the profiles of both the dry red soils and the Vertisols, but activities of polyphenol oxidase and acid and neutral phosphatase showed the same tendencies only in the Vertisols. It was concluded that the characteristics of soil animals, microorganisms and enzymatic activity could be used as the bio-indicators to show the degradation degree of the dry red soils and Vertisols. Correlation among these soil bio-indicators was highly significant.

关键词： degraded soil ecosystem soil enzyme soil fauna soil microbes

Adaptation Management of mountain Tourism Service: The Case of the Source Regions of the Yangtze and Yellow River

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Journal of mountain Science 2009年第3期6卷 299-310页

作者： FANG Yiping QIN Dahe DING Yongjian YANG Jianping institute of mountain {2. & environment Chinese Academy of Sciences 610041 Chengdu China Cold and Arid Regions environmental and Engineering Research institute Chinese Academy of Sciences 730000 Lanzhou China

mountain areas are often rich in ecological diversity and recreational opportunities. mountain tourism is thought to be an effective and important means for maintaining and expanding rural economies and, thus, improving the living conditions of rural societies. As mountain tourism service research is a professional field with several disciplines involved, a multi-disciplinary management pIatform is needed and it facilitates participation in sustainable mountain development by diverse stakeholders. With the source regions of the Yangtze and the Yellow River as a case study, this paper presents a conceptual framework for an adaptation management of mountain tourism services according to technical, policy, social and economic dimensions. The framework is based on a vulnerability assessment of mountain ecosystems, and can serve as a reference for the development of tourism service in other mountain areas.

关键词： adaptation management mountain tourism service (MTS) source regions of Yangtze and Yellow Rivers china

^(137)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-137(137 Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 137 Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 137 Cs redistribution in a karst area of Southwest *** results indicated that the 137 Cs inventories of the surface soil on the slope studied were much lower than that of the local 137 Cs reference inventory and the 137 Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 137 Cs inventories was characterized by considerable *** high 137 Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 137 Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 137 *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 137 Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^137Cs fallout, ^137Cs inventory karst area runoff

Study on ground temperature change and characteristic response of engineering geology of permafrost along Qinghai-Tibet Railway

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Science china(Technological sciences) 2003年第Z1期46卷 78-90页

作者： PAN Weidong, WANG Quancai, YU Shaoshui & ZHANG Xiaoyan Department of Mechanics, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, china institute of {2. hazards and environment, chinese academy of sciences and Ministry of Water Resources, chengdu 61004., china State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions environment and Engineering Research institute, chinese academy of sciences, Lanzhou 730000, china {12. Provincial Communications Department, chengdu 61004., china Lanzhou Univ Dept Mech Sch Phys Sci & Technol Lanzhou 730000 Peoples R China chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China chinese Acad Sci State Key Lab Frozen Soil Engn Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China sichuan Prov Commun Dept Chengdu 610041 Peoples R China

Along with the global warming in the recent scores of years, comparatively big changes have taken place in the weather and other environmental conditions of the permafrost area in the Qinghai-Tibet Plateau, and very big changes have also occurred in the engineering geological conditions of the permafrost area. Based on a large volume of field survey data, this paper discusses the regularities of horizontal and vertical distribution of permafrost, with its focus of analysis on the temperature change characteristics of the soil in different frozen-soil zones, as well as presents simulation analysis and research for the engineering geologic characteristic response changes that would occur in the future when the temperature of the frozen soil in different zones rises by 1 and 2.6℃ respectively, which will have a tremendous impact on the stability of constructional work.

关键词： Qinghai-Tibet Railway, permafrost, ground temperature, engineering geological characteristic.

Some open problems in granular matter mechanics

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Progress in Natural Science:Materials International 2009年第5期19卷 523-529页

作者： Qicheng Sun a, Guangqian Wanga, Kaiheng Hub a Department of Hydraulic Engineering, State Key Laboratory for Hydroscience and Engineering, Tsinghua University, Beijing 100084, china b institute of {2. hazards and environment, chinese academy of sciences, chengdu 61004., china Department of Hydraulic Engineering State Key Laboratory for Hydroscience and Engineering Tsinghua University Beijing 100084 China institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610041 China

Granular matter is a large assemblage of solid particles, which is fundamentally different from any other type of matters, such as solid and liquid. Most models presented for granular matter are phenomenological and are only suitable for solving engineering problems. Many fundamental mechanical problems remain open. By analyzing characteristics of internal state structure, we propose that granular matter is intrinsically multiscale, i.e. microscale of particle size, mesoscale of force chain, and macroscale of the bulk of granular matter. The correlations among difference scales would be crucial. The mesoscale force chain network is determined by both particle properties and macroscopic boundary conditions. The evolution of the force the chain network contributes to macroscopic mechanical properties of granular matter. In addition, we discuss the drawbacks in simplifying contact forces in the current models, and the difficulties in analyzing the interaction of interstitial fluid in wet granular matter. As an appropriate application of granular matter, debris flow can be studied with granular matter mechanics; meanwhile, debris flow brings more challenges which certainly motivate future studies on granular matter.

关键词： Granular matter Multiscale mechanics Force chain Contact mechanics Debris flow