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Optimization Design of Warping Dam in Wangjiagou, Shanxi Province

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Wuhan University Journal of Natural sciences 2003年第3B期8卷 1007-1011页

作者： zhang Yu, Cui Peng, Li Fa-bin, Wang Qing{1. of mountain {3. and environment. chinese academy of sciences, chengdu 61004., sichuan, china institute of {1. hazards and {3. Chinese Academy of Sciences Chengdu 610041 SichuanChina

This paper introduces the simulating design of warping dam in the Loess Plateau, western Shanxi province. On the basis of collected data, the digital elevation model in the studied area has been created. Utilizing GIS (geographical information system) technology, this paper achieves some environmental based results with the simulation method. Also based on the parameter model of precipitation, the tendency of warping sand has been calculated, aiming at providing academic basis for optimization design in the small watershed.

关键词： small watershed protective engineering GIS technology optimization

Mathematical Analyses for the influence of Soil Conditions and Nntrient Interactions on Cotton Yields

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Pedosphere 1994年第3期4卷 255-263页

作者： zhang JIANHUI TANG SHIJIA LUO YOUFANG HU CHANGQING and YANGXIAO(Department of Soil Science, {1. of mountain {3. and environment, chinese academy of sciencesand Ministcy of Water Conseruancy, chengdu 61.O41.(china))(Cotton {1., Si

he influence of soil chemical properties and soil nutrition on cotton yields was studied by means ofestablishing mathematical models. The nultivariate quadratic regression equations developed by a stepwiseregression method not only presented the single effect of soil factors but also displayed the interaction (syn-ergistic or antagonistic) of soil nutrients. The effect of individual factor and the way of nutrient interactionwere further analysed by the path analysis method. The results showed that among major factors affectingcotton yields, there existed the interactions between macronutrients(available P × available K), and betweenmacronutrients and microelements (N×Zn, P×Mo, P×Cu, P × Zn, K×Mo) besides the single effect of soilpH, total P, available Cu and available Zn.

关键词： combined effect cotton yield multivariate quadratic regression path analysis soil nutrient

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生化标记和分子标记在蕈菌研究中的应用现状

天然产物研究与开发 2004年第6期16卷 590-596页

作者：张丹郑有良四川农业大学

本文介绍了目前在蕈菌研究中的酯酶同工酶标记 ,RAPD标记 ,RFLP标记 ,AFLP标记 ,简单重复序列标记和电泳核型等分子标记和生化标记在蕈菌遗传育种、菌株鉴定、遗传多样性研究、亲缘关系和基因定位等方面的研究、应用现状 ,包括原理、应... 详细信息

本文介绍了目前在蕈菌研究中的酯酶同工酶标记 ,RAPD标记 ,RFLP标记 ,AFLP标记 ,简单重复序列标记和电泳核型等分子标记和生化标记在蕈菌遗传育种、菌株鉴定、遗传多样性研究、亲缘关系和基因定位等方面的研究、应用现状 ,包括原理、应用领域及最新研究进展。

关键词：蕈菌分子标记生化标记 RFLP标记 AFLP标记 RAPD标记遗传育种菌株鉴定研究电泳核型

Antecedent snowmelt and orographic precipitation contributions to water supply of Pakistan disastrous floods,2022

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Advances in Climate Change Research 2024年第3期15卷 419-430页

作者： Yan WANG Peng CUI Chen-Di zhang Guo-Tao zhang Jian-Sheng HAO Xu yuan Yao-Zhi JIANG Lu WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of mountain {1. and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China Polar and Marine Research institute College of Harbor and Coastal EngineeringJimei UniversityXiamen 361021China School of Resources and environment University of Electronic Science and Technology of ChinaChengdu 610054China Hebei Province Tangshan Caofeidian Meteorological Bureau Tangshan 063000China

In 2022,the Pakistan witnessed the hottest spring and wettest summer in *** devastating floods inundated a large portion of Pakistan and caused enormous ***,the primary water source and its contributions to these unprecedented floods remain *** on the reservoir inflow measurements,Multi-Source Weighted-Ensemble Precipitation(MSWEP),the fifth generation ECMWF atmospheric reanalysis(ERA5)products,this study quantified the contributions of monsoon precipitation,antecedent snow-melts,and orographic precipitation enhancement to floods in *** found that the Indus experienced at least four inflow up-rushes,which was mainly supplied by precipitation and snowmelt;In upper Indus,abnormally high temperature continued to influence the whole summer and lead to large amounts of snowmelts which not only was a key water supply to the flood but also provided favorable soil moisture conditions for the latter *** July,the snowmelt has higher contributions than the precipitation to the streamflow of Indus River,with contribution value of more than 60%.Moreover,the snowmelt could still supply 20%-40%water to the lower Indus in July and August;The leading driver of 2022 mega-floods over the southern Pakistan in July and August was dominated by the precipitation,where terrain disturbance induced precipitation account to approximately 3.%over the southern *** results help to understand the mechanisms of flood formation,and to better predict future flood risks over complex terrain regions.

关键词： Extreme heavy rainfall Snowmelt Orographic precipitation Floods Pakistan

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山区花卉的生态旅游价值

山地学报 2008年第S1期26卷 93-96页

作者：马培张丹中国科学院水利部成都山地灾害与环境研究所中国科学院研究生院

作为绿色消费的生态旅游已经迅速普及到全球,我国的生态旅游业也迅速发展起来,但在其开发中面临如何丰富、深化其内涵的问题。针对山区丰富的花卉资源花色斑斓、千姿百态、四季花开不断等特点,对其在发展生态旅游中的造景功能、审美价... 详细信息

作为绿色消费的生态旅游已经迅速普及到全球,我国的生态旅游业也迅速发展起来,但在其开发中面临如何丰富、深化其内涵的问题。针对山区丰富的花卉资源花色斑斓、千姿百态、四季花开不断等特点,对其在发展生态旅游中的造景功能、审美价值、历史文化价值、生态价值以及旅游品牌开发价值等方面进行了讨论。

关键词：花卉山区旅游价值

The Analysis of CO2 Influence Factors in Tianquan Cave of Xingwen World Geopark

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四川地质学报 2009年第S1期 113-119页

作者： SHUI Wei 1 HU Yi 2 zhang Bing 3.SU Zheng-an 4 WANG Chen-yi 2 REN De-you 3.XU Xue-yi 1 CHENG Jin-ping 2(1.Department of Eco-agriculture and Rural Development,{3. Agricultural University,Ya'an 625014,{3. 2.College of Resources and environment,{3. Agricultural University,Ya'an 625014,{3. 3.School of Land and Resources,china West Normal University,Nanchong 63.002,{3. 4.institute of mountain hazards and environment,chinese academy of sciences and Ministry of Water Conservancy,chengdu 61004.,{3.)

A Vaisala CARBOCAP Hand-Held Carbon Dioxide Meter GM70 was used to measure CO 2 concentration in Tianquan cave of Xingwen world *** study was done in Tianquan cave during July and August,*** sources include the influence factors of distribution of CO 2:elevation,tourists,cross section and depth of the *** indicated tourists have strong impacts on the CO 2 concentration,while no significant differences could be found among different ***,significant correlation could be found among the depth of cave,the small cross section,the tourist's construction and the CO 2 *** results indicate that the CO 2 concentration in Tianquan cave has no threat to the health of *** results and the data provide a scientific basis for the protection of people's health and the exploitation of cave tourism.

关键词： Xingwen world Geopark Tianquan cave CO 2 concentration Influence factors

Nutrient enrichment driven by canopy rainfall redistribution:Mechanism,quantification,and pattern

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Science china Earth {1. 2024年第5期67卷 1529-1544页

作者： Chuan yuan Xiaoping YUE Yafeng {1. Yu {1. Yanting HU Qiang TANG Li GUO Shuai WANG Xingwu DUAN Wenhua XIANG Xiaohua WEI Xiaoyan LI College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China Chongqing Jinfo mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geographical sciences Hebei Normal UniversityShijiazhuang 050024China Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of Hydraulics and mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China Department of Earth Environmental and Geographic SciencesUniversity of British Columbia(Okanagan)KelownaBritish Columbia V1V 1V7Canada

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow,which transfer substantial amounts of elements into the soil,influencing soil microbial community,plant survival,and plant community *** advancements in ecohydrological research,the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely *** address this gap,we conducted a systematic review of 1.20 papers published between 2000 and 2022,gathering data on nutrient concentration and enrichment for critical ions(including K^(+),Na^(+),Ca^(2+),Mg^(2+),NH_(4)^(+),Cl^(-),NO_(3.^(-)and SO_(4)^(2-))from the Web of Science and {1. Knowledge Infrastructure *** aimed to synthesize the mechanisms,quantify the enrichments,and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones,and vegetation types and *** results of this study indicate that stemflow exhibits,on average,2.1.imes greater ion concentration(6.1.0}mg L^(-1.)compared to *** particular,among the investigated ions,SO_(4)^(2-)(1..45and 6.3. mg L^(-1.)for stemflow and throughfall,respectively,and Cl^(-)(9.21.and 4.81.mg L^(-1.)exhibit the highest concentrations in both rainfall redistribution components,while K^(+)(1.0}7 and 5.8)and Mg^(2+)(5.6 and 2.8)have the highest enrichment *** climate zones,throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid *** the temperature gradient,ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing *** addition,shrubs,conifers,mixed forests,and artificial ecosystems demonstrate enrichment factors 1.1.to 3.0 times greater than those of trees,broad-leaved plants,pure forests,and natural *** findings emphasize the need for increased attentions to artificial ecosystems,such as urban

关键词： Ecohydrology Rainfall redistribution Nutrients transport Enrichment characteristics Climate zones

Erosion and Sediment Production in Small Watershed in Purple Hilly Areas and Prevention Techniques

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Wuhan University Journal of Natural sciences 2003年第3B期8卷 1041-1046页

作者： zhang Bao-hua, He Yu-rong, Zhou Hong-yi, Zhu Bo{1. of mountain {3. and environment, chinese academy of sciences, chengdu 61004., sichuan, china Department of Geography, Liaocheng University, Liaocheng 252059, Shandong, china institute of {1. hazards and {3. Chinese Academy of Sciences Chengdu 610041 SichuanChina Department of Geography Liaocheng UniversityLiaocheng 252059 Shandong China institute of {1. hazards and {3. Chinese Academy of Sciences Chengdu 610041 SichuanChina

Purple Soil distributes extensively and mainly in china. Because of abundant easily weatherable parent rocks/ materials and unstable soil structure, and also influenced by parent materials, usage systems, and slope gradients, erosion and sediment production of purple soils are very severe with main fashions of water erosion and gravitational erosion. Basing on observed data in small watersheds, rainfall erosivity, vegetation coverage, previous soil water content, flow and relating factors such as climate, topograph of small watershed, land usage, and soil kinds are all the influence factors of erosion and erodibility of purple soil as well as sediment production and transport in small watershed of purple hilly areas. The effective technological countermeasures of ecosystem restoration, agricultural tillage for water conservation and erosion prevention, agriculture project, and soil changing for fertility and anti-erosion were provided.

关键词： purple soil characteristics of erosion and sediment production) influence factors prevention techniques

Dynamic response and failure process of horizontal-layered fractured structure rock slope under strong earthquake

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Journal of mountain Science 2024年第3期21卷 882-900页

作者： WANG Tong LIU Xianfeng HOU Zhaoxu XU Jiahang zhang Jun {1. Shengyang JIANG Guanlu HU Jinshan School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-Speed Railway Engineering of Ministry of Education Southwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Xinjiang Institute of EngineeringUrumqi 830023China china Railway First Survey and Design {1. Group Co.LTD Xi'an 710043China

Rock slope with horizontal-layered fractured structure(HLFS)has high stability in its natural ***,a strong earthquake can induce rock fissure expansion,ultimately leading to slope *** this study,the dynamic response,failure mode,and spectral characteristics of rock slope with HLFS under strong earthquake conditions were investigated based on the large-scale shaking table model *** this basis,multiple sets of numerical calculation models were further established by UDEC discrete element *** influencing factors were considered in the parametric study of numerical simulations,including slope height,slope angle,bedding-plane spacing and secondary joint spacing as well as bedrock dip *** results showed that the failure process of rock slope with HLFS under earthquake action is mainly divided into four phases,i.e.,the tensile crack of the slope shoulder joints and shear dislocation at the top bedding plane,the extension of vertical joint cracks and increase of shear displacement,the formation of step-through sliding surfaces and the instability,and finally collapse of fractured rock *** acceleration response of slopes exhibits elevation amplification effect and surface *** simulations indicate that the seismic stability of slopes with HLFS exhibits a negative correlation with slope height and angle,but a positive correlation with bedding-plane spacing,joint spacing,and bedrock dip *** results of this study can provide a reference for seismic stability evaluation of weathered rock slopes.

关键词： Seismic behavior Horizontal layered Weathered rock slope Shaking table test Failure mode