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Acta Geochimica 2017年第3期36卷 572-576页

作者： Pin Lü guilin Han Qixin Wu School of Water resources and Environment China University of Geosciences (Beijing) Key laboratory of karst Environment and Geohazard Ministry of Land and Resources Guizhou University

The chemical composition of rainwater has been studied in a karst rural area from September 2012 to August 2013 in Guizhou Province,Southwest *** results indicated that the VWM value of p H was 5.4,varied from 4.6 to ***^(2+)and NH_4^+were the major cations,and SO_4^(2-)was the dominant *** factors show that the acid was mainly neutralized by Ca^(2+),NH_4^+and Mg^(2+).Investigations of correlation coefficients and enrichment factors revealed that Ca^(2+)and Mg^(2+)were mainly crust origins,and NH_4^+was from agriculture and livestock ***_4^(2-)and NO_3^-were mainly from anthropogenic sources.

关键词： Chemical composition Rainwater karst rural area Southwest china

NPP vulnerability of the potential vegetation of china to climate change in the past and future

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Journal of Geographical Sciences 2017年第2期27卷 131-142页

作者： YUAN Quanzhi WU Shaohong DAI Erfu ZHAO Dongsheng REN Ping ZHANG Xueru Key Lab of land resources Evaluation and Monitoring in Southwest Ministry of Education Sichuan NormalUniversity Chengdu 610068 China Institute of Geography and resources Science Sichuan Normal University Chengdu 610101 China Institute of Geographic Sciences and Natural resources Research CAS Beijing 100101 China Key laboratory of land Surface Pattern and Simulation CAS Beijing 100104 China Chongqing Jiaotong University Chongqing 400074 China

Using the Integrated Biosphere Simulator, a dynamic vegetation model, this study initially simulated the net primary productivity（NPP） dynamics of china＇s potential vegetation in the past 55 years（1961–2015） and in the future 35 years（2016–2050）. Then, taking the NPP of the potential vegetation in average climate conditions during 1986–2005 as the basis for evaluation, this study examined whether the potential vegetation adapts to climate change or not. Meanwhile, the degree of inadaptability was evaluated. Finally, the NPP vulnerability of the potential vegetation was evaluated by synthesizing the frequency and degrees of inadaptability to climate change. In the past 55 years, the NPP of desert ecosystems in the south of the Tianshan Mountains and grassland ecosystems in the north of china and in western Tibetan Plateau was prone to the effect of climate change. The NPP of most forest ecosystems was not prone to the influence of climate change. The low NPP vulnerability to climate change of the evergreen broad-leaved and coniferous forests was observed. Furthermore, the NPP of the desert ecosystems in the north of the Tianshan Mountains and grassland ecosystems in the central and eastern Tibetan Plateau also had low vulnerability to climate change. In the next 35 years, the NPP vulnerability to climate change would reduce the forest–steppe in the Songliao Plain, the deciduous broad-leaved forests in the warm temperate zone, and the alpine steppe in the central and western Tibetan Plateau. The NPP vulnerability would significantly increase of the temperate desert in the Junggar Basin and the alpine desert in the Kunlun Mountains. The NPP vulnerability of the subtropical evergreen broad-leaved forests would also increase. The area of the regions with increased vulnerability would account for 27.5% of china.

关键词： climate change vulnerability potential vegetation net primary productivity IBIS china

Vortex genesis over the Bay of Bengal in spring and its role in the onset of the Asian Summer Monsoon

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Science china Earth Sciences 2011年第1期54卷 1-9页

作者： WU GuoXiong1, GUAN Yue1,2, WANG TongMei3, LIU YiMin1, YAN JingHui4 & MAO JiangYu1 1 State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid dynamics (LASG), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2Graduate University of Chinese Academy of Sciences, Beijing 100049, china 3Department of Atmospheric Science, Sun Yat-Sen University, Guangzhou 510275, china 4National Climate Center, china Meteorological Administration, Beijing 100080, china State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China Department of Atmospheric Science Sun Yat-Sen University Guangzhou China National Climate Center China Meteorological Administration Beijing China

Physical processes associated with onset of the 1998 Asian summer monsoon were examined in detail using multi-source datasets. We demonstrated that strong ocean-atmosphere-land interaction in the northern Indian Ocean and tropical Asian area during spring is a fundamental factor that induces the genesis and development of a monsoon onset vortex over the Bay of Bengal (BOB), with the vortex in turn triggering onset of the Asian summer monsoon. In spring, strong surface sensible heating over India and the Indochina Peninsula is transferred to the atmosphere, forming prominent in situ cyclonic circulation, with anticyclonic circulations over the Arabian Sea and northern BOB where the ocean receives abundant solar radiation. The corresponding surface winds along the North Indian Ocean coastal areas cause the ocean to produce the in situ offshore currents and upwelling, resulting in sea surface temperature (SST) cooling. With precipitation on the Indochina Peninsula increasing from late April to early May, the offshore current disappears in the eastern BOB or develops into an onshore current, leading to SST increasing. A southwest-northeast oriented spring BOB warm pool with SST >31°C forms in a band from the southeastern Arabian Sea to the eastern BOB. In early May, the Somali cross-equatorial flow forms due to the meridional SST gradient between the two hemispheres, and surface sensible heat over the African land surface. The Somali flow overlaps in phase with the anticyclone over the northern Arabian Sea in the course of its inertial fluctuation along the equator. The convergent cold northerlies on the eastern side of the anticyclone cause the westerly in the inertial trough to increase rapidly, so that enhanced sensible heat is released from the sea surface into the atmosphere. The cyclonic vorticity forced by such sensible heating is superimposed on the inertial trough, leading to its further increase in vorticity strength. Since atmospheric inertial motion is destr

关键词： air-sea interaction spring BOB warm pool monsoon onset vortex inertial oscillation Asian summer monsoon onset

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岩溶坡地土壤侵蚀强度的137Cs法研究

山地学报 2007年第3期25卷 302-308页

作者：张治伟傅瓦利张洪夏凯生西南大学地理科学学院西南大学地理科学学院重庆400715 国土资源部岩溶动力学重点实验室广西桂林541004

在重庆南部南川市境内,按不同侵蚀强度取137Cs样品,用于研究岩溶坡地不同侵蚀程度的土壤侵蚀强度与特征。结果表明,林草地侵蚀速率变化范围49.3 t/(km2.a)~230.5 t/(km2.a),平均侵蚀速率112.5 t/(km2.a);缓坡耕地侵蚀速率变化范围190.3~... 详细信息

在重庆南部南川市境内,按不同侵蚀强度取137Cs样品,用于研究岩溶坡地不同侵蚀程度的土壤侵蚀强度与特征。结果表明,林草地侵蚀速率变化范围49.3 t/(km2.a)~230.5 t/(km2.a),平均侵蚀速率112.5 t/(km2.a);缓坡耕地侵蚀速率变化范围190.3~1 138.4 t/(km2.a),平均565.5 t/(km2.a);陡坡耕地的侵蚀速率变化范围为452.0~3 759.4 t/(km2.a),平均2 264.8 t/(km2.a)。与黄土高原和紫色土区相比,岩溶区侵蚀速率较小。

关键词：岩溶区不同侵蚀强度 137Cs法研究

3D visualization model and key techniques for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 748-752页

作者： JIN Bao-xuan1,FANG Yuan-min2,SONG Wei-wei2 1. Yunnan Provincial Geomatics Centre, Kunming 650034, china 2. Faculty of land Resource Engineering, Kunming University of Science and Technology, Kunming 650093, china Yunnan Provincial Geomatics Centre Kunming 650034 China Faculty of land Resource Engineering Kunming University of Science and Technology Kunming 650093 China

Digital mine is the inevitable outcome of the information processing, and is also a complicated system engineering. Firstly, for the 3D visualization application of the digital mine, the ground and underground integrative visualization framework model was proposed based on the mine entity database. So, the visualization problem was availably resolved, as well as the professional analytical ability was improved. Secondly, aiming at the irregularities, non-uniformity, dynamics of mine entities, mix modeling method based on the entity character was put forward, in which 3D expression of mine entities was realized. Lastly, the 3D visualization project for a copper mine was experimentally studied. Satisfactory results were acquired, and the rationality of visualization model and feasibility of 3D modeling were validated.

关键词： digital mine three dimension visualization framework model spatial data modeling

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冲锤处流体阻力对高能射流式液动锤性能影响

振动．测试与诊断 2016年第5期36卷 998-1002页

作者：张鑫鑫彭枧明杨冬冬吴冬宇孙强吉林大学建设工程学院/国土资源部复杂条件钻采技术重点实验室长春130026

应用计算流体动力学(computational fluid dynamics,简称CFD)动态分析技术,对SC-86H型高能射流式液动锤试验样机流场特性进行了研究,计算得出了相关性能参数,并通过实验装置对液动锤不同输入流量下的冲击频率进行了测试。将液动锤冲击... 详细信息

应用计算流体动力学(computational fluid dynamics,简称CFD)动态分析技术,对SC-86H型高能射流式液动锤试验样机流场特性进行了研究,计算得出了相关性能参数,并通过实验装置对液动锤不同输入流量下的冲击频率进行了测试。将液动锤冲击频率的模拟计算结果与实测结果进行了对比,结果表明:若不考虑冲锤处流体阻力的影响,液动锤冲击频率计算值与实测值相比明显偏大,最小相对误差达18.9%;而将冲锤处流体阻力的作用考虑在内,冲击频率的计算值与实测值比较接近,最大相对误差为8.0%,大幅提高了数值计算结果与实测值之间的吻合程度。这说明冲锤高速运动产生的轴向流体阻力不容忽略,设法减小冲锤处流体阻力的大小,有望成为提高高能射流式液动锤冲击功和能量利用率的重要途径。

关键词：计算流体动力学射流式液动锤冲锤流体阻力冲击频率

Ecological-sedimentary zonations and carbonate deposition,Xiaodonghai Reef Flat,Sanya,Hainan Island,china

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Science china Earth Sciences 2011年第3期54卷 359-371页

作者： WANG Yue1,2, SHEN JianWei1 & LONG JiangPing3 1 Department of Marine Geology, South china Sea Institute of Oceanology CAS Key laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, china 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, china 3 The Second Institution of Oceanography, State Oceanic Administration, Hangzhou 310012, china Department of Marine Geology South China Sea Institute of Oceanology Guangzhou China Graduate University of Chinese Academy of Sciences Beijing China CAS Key laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China The Second Institution of Oceanography State Oceanic Administration Hangzhou China

Modern fringing reefs are developed on the intertidal to subtidal area of Xiaodonghai bay, Sanya, Hainan Island. The reef flat extends several dozen meters toward the sea. Various ecological and sedimentary zonations can be distinguished, including, from land to sea, beachrocks, large massive corals, inner reef flat, outer reef flat, and fore-reef slope. The carbonate sediments and constituent hermatypic coral communities are different in these zones. The beachrocks are composed mainly of biological sands, including coral skeletons, algae, gastropods, bivalves, and benthic foraminifera. Quartz sands are less common in this zone. Carbonate diagenesis in beachrocks is characterized by early cementation. The fringing reef flat is progradationally developed toward the sea. Large massive corals grew in the zone next to the beachrocks. These corals are large, flat-toped, and autochthonous in the production of bioclastic grains and lime mud. Large and massive coral skeletons are surrounded by coral skeletal grains, bioclasts, and lime-mud sediments. The inner reef flat consists mainly of skeletons of branching corals that are covered by bioclasts and lime mud, and living corals are mostly massive in form. Statistical analysis of coral-community dynamics shows that the outer reef flat with strong waves is the most suitable place for hermatypic corals to flourish. There, the living corals are most densely distributed. Both massive corals and branching corals (e.g., Acropora corymbosa) are exceptionally healthy in this zone. Bioclasts and lime mud are washed out due to strong wave action. Microbial carbonates generally are deposited within cavities of the beachrocks and coral skeletal cavities and on the surfaces of bioclastic grains. The latter two types, however, are more common. Ecological-sedimentary zonations across the Xiaodonghai reef flat from beachrocks to outer reef flat are controlled by variations in wave strength and water energy. Microbial carbonates rarely deve

关键词： microbial carbonates ecological-sedimentary zonation cementation reef flat Hainan Island

Large-diameter trees and deadwood correspond with belowground ectomycorrhizal fungal richness

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Ecological Processes 2023年第1期12卷 31-45页

作者： Joseph D.Birch James A.Lutz Soren Struckman Jessica R.Miesel Justine karst Department of Plant Soil and Microbial SciencesMichigan State University1066 Bogue StreetEast LansingMI 48824USA Department of Wildland resources and the Ecology Center Utah State University5230 Old Main HillLoganUT 84322-5230USA Department of Renewable resources University of Alberta751 General Services BuildingEdmontonAB T6G 2H1Canada

Background: Large-diameter trees have an outsized influence on aboveground forest dynamics, composition, and structure. Although their influence on aboveground processes is well studied, their role in shaping belowground fungal communities is largely unknown. We sought to test if (i) fungal community spatial structure matched aboveground forest structure;(ii) fungal functional guilds exhibited differential associations to aboveground trees, snags, and deadwood;and (iii) that large-diameter trees and snags have a larger influence on fungal community richness than smaller-diameter trees. We used MiSeq sequencing of fungal communities collected from soils in a spatially intensive survey in a portion of Cedar Breaks National Monument, Utah, USA. We used random forest models to explore the spatial structure of fungal communities as they relate to explicitly mapped trees and deadwood distributed across 1.15 ha of a 15.32-ha mapped subalpine forest. Results: We found 6,177 fungal amplicon sequence variants across 117 sequenced samples. Tree diameter, dead-wood presence, and tree species identity explained more than twice as much variation (38.7% vs. 10.4%) for ectomy-corrhizal composition and diversity than for the total or saprotrophic fungal communities. Species identity and dis-tance to the nearest large-diameter tree (≥ 40.2 cm) were better predictors of fungal richness than were the identity and distance to the nearest tree. Soil nutrients, topography, and tree species differentially influenced the composition and diversity of each fungal guild. Locally rare tree species had an outsized influence on fungal community richness. Conclusions: These results highlight that fungal guilds are differentially associated with the location, size, and species of aboveground trees. Large-diameter trees are implicated as drivers of belowground fungal diversity, particularly for ectomycorrhizal fungi.

关键词： Belowground ecology Ectomycorrhizal fungi Pinus flexilis Pinus longaeva Saprotrophic fungi Smithsonian ForestGEO Spatial dynamics Utah Forest dynamics Plot

长江三峡地区一级阶地堆积物地球化学特征——以江津油溪剖面为例

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山地学报 2010年第5期28卷 519-525页

作者：夏凯生何多兴谢世友袁道先西南大学地理科学学院西南大学三峡库区教育部重点实验室中国地质科学院岩溶地质研究所、国土资源部岩溶动力学重点实验室

采用14C法对江津油溪剖面长江三峡一级阶地上部砾岩层胶结年代进行测定以及填隙物的Fe2O3、FeO、CaO、MgO及Fe2O3/FeO等变化特征进行了分析,下部松散砾石层填隙物氧化物特征为:Fe2O3含量及Fe2O3/FeO比值较高,FeO、CaO、MgO含量较低;胶... 详细信息

采用14C法对江津油溪剖面长江三峡一级阶地上部砾岩层胶结年代进行测定以及填隙物的Fe2O3、FeO、CaO、MgO及Fe2O3/FeO等变化特征进行了分析,下部松散砾石层填隙物氧化物特征为:Fe2O3含量及Fe2O3/FeO比值较高,FeO、CaO、MgO含量较低;胶结砾岩填隙物的氧化物特征则相反。研究结果表明,本阶地的形成年代为距今13.4～40ka;晚更新世晚期的气候变化可能是剖面氧化物变化特征的原因。

关键词： 14C 胶结年代填隙物氧化物一级阶地长江三峡地区