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NUMERICAL MODELING OF COMPOUND CHANNEL FLOWS

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Journal of Hydrodynamics 2002年第4期14卷 106-109页

作者： Wang De-guan, Cheng Li college of Water resources and environmental Engineering, Hohai{3., nanjing 210098, China college of Water resources and environmental Engineering Hohai University Nanjing 210098 China

A numerical model capable of predicting flow characteristics in a compound channel was established with the 3.D steady continuity and momentum equations along with the transport equations for turbulence kinetic energy and dissipation rate. Closure was achieved with the aid of algebraic relations for turbulent shear stresses. The above equations were discretized with implicit difference approach and solved with a step method along the flow direction. The computational results showing the lateral distribution of vertical average velocities and the latio of total flow in the compound channel agree well with the available experimental data.

关键词： compound channel flow discharge ratio of channel and floodplain turbulence

Study on Water Consumption Coefficient of People's Living and Its Regional Disparity in the North of China

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Chinese Journal of Population,resources and Environment 2005年第2期3卷 20-26页

作者： Wang Jing’ai 1-3. Mao Rui 3.4, Yang Mingchuan 3.4 & Zhou Junju 11 college of Geography & Remote Sensing 2 Key Laboratory of Regional Geography of Beijing Normal university 3.Key Laboratory of environmental Change and Natural Disaster of Ministry of Education of China 4 college of resources science & Technology, Beijing Normal university, Beijing 100875, China college of Geography and Remote Sensing Beijing 100048 China Key Laboratory of environmental Change and Natural Disaster of Ministry of Education of China Beijing 100048 China college of resources science and Technology Beijing Normal University Beijing 100875 China

By employing the information-reshufflingmethod that integrates census data, precipitation dataand inquiry data of water consumption, this paperdiscusses 5 (water consumption coefficient of people’sliving) in allusion to different precipitation zones anddifferent periods of time. The study shows that 5-(water consumption coefficient of urban people’sliving), 5. (water consumption coefficient of ruralpeople’s living) and increase with time passing, andthe increasing extent of 5 is 1.84, 2.62, 2.84 and 2.68times respectively from the west to the east, whichresults from the total quantity of water resources andthe speed of urbanization. 5- and 5. of eachprecipitation zone increased with 5- increasing morequickly than 5., and the difference between the twoalso increased when time passed. In the past fifty years(1950-2000), the increasing extent of 5- was 1.71,2.96, 2.41 and 2.3. times respectively from the westto the east, in which 200-400mm precipitation zoneincreased more than others. Meanwhile the increasingextent of 5. is 1.55, 1.60, 1.53.and 1.64 timesrespectively from the west to the east with eachprecipitation zone increasing similarly. The change of5-is due to the speed of urbanization and the stabilityof water resources. This study provides basis forcalculating the water demand of people’s living andrevealing the impact of water demand of people’s livingon ecological drought in different zones.

关键词： The north of China precipitation zone water consumption coefficient of people’s living

Land Use and Soil Organic Carbon in China’s Village Landscapes

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Pedosphere 2010年第1期20卷 1-14页

作者： JIAO Jia-Guo YANG Lin-Zhang WU Jun-Xi WANG Hong-Qing LI Hui-Xin E. C. ELLIS Department of resources and environmental sciences Nanjing Agricultural University Nanjing210095 （China） Institute of Soil science Chinese Academy of Sciences Nanjing 210008 （China） Department of Agronomy and Agroecology China Agricultural University Beijing 100094 （China） Department of Geography ＆ environmental Systems University of Maryland Baltimore County Baltimore 21250 （USA） Center for Louisiana Inland Water Studies University of Louisiana at Lafayette Lafayette Louisiana （USA）

Village landscapes, which integrate small-scMe agriculture with housing, forestry, and a host of other land use practices, cover more than 2 million square kilometers across China. Village lands tend to be managed at very fine spatial scales （≤ 3. m）, with managers both adapting their practices to existing variation in soils and terrain （e.g., fertile plains vs. infertile slopes） and also altering soil fertility and even terrain by terracing, irrigation, fertilizing, and other land use practices. Relationships between fine-scale land management patterns and soil organic carbon （SOC） in the top 3. cm of village soils were studied by sampling soils within fine-scale landscape features using a regionally weighted landscape sampling design across five environmentally distinct sites in China. SOC stocks across China＇s village regions （5 Pg C in the top 3. cm of 2 ×10^6 km^2） represent roughly 4% of the total SOC stocks in global croplands. Although macroclimate varied from temperate to tropical in this study, SOC density did not vary significantly with climate, though it was negatively correlated with regional mean elevation. The highest SOC densities within landscapes were found in agricultural lands, especially paddy, the lowest SOC densities were found in nonproductive lands, and forest lands tended toward moderate SOC densities. Bue to the high SOC densities of agricultural lands and their predominance in village landscapes, most village SOC was found in agricultural land, except in the tropical hilly region, where forestry accounted for about 45% of the SOC stocks. A surprisingly large portion of village SOC was associated with built structures and with the disturbed lands surrounding these structures, ranging from 〉 18% in the North China Plain to about 9% in the tropical hilly region. These results confirmed that local land use practices, combined with local and regional variation in terrain, were associated with most of the SOC variation within and across China＇s

关键词： agriculture land cover change land use change soil carbon sequestration spatial heterogeneity

Commelina communis L.: Copper Hyperaccumulator Found in Anhui Province of China

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Pedosphere 1997年第3期7卷 207-210页

作者： TANG SHIRONG HUANG CHANGYONG and ZHU ZUXIANG (Department of Soil science, college of environmental sciences and Natural resources, Zhejiang agricultural university, Hangzhou 3.0029 China) Department of Soil science College of Environmental Sciences and Natural Resources Zhejiang Agricultural University Hangzhou 310029 China

Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, China, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (443.±243.) mg kg-1, 3.9-83. (73.±142) mg kg-1, and 429-587 (547±57) mg kg-1, respectively, in the roots, stems, and leaves. The soils supporting the growth of the species had a copper concentration ranging from 4620 to 5020 mg kg-1 and averaging 483.±262 mg kg-1, suggesting that the species could not only grow on heavily copper-contaminated soils but also accumulate extraordinarily high concentration of copper. Thus, it shows great potential in the phytoremediation of copper-contaminated soils,the restoration of mined land, geochemical prospecting, and the study of environmental pollution changes.

关键词： Anhui Province Commelina communis L. copper hyperaccumulator

Heterogeneous reaction of NO_2 with sea salt particles

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science China Chemistry 2010年第12期53卷 2652-2656页

作者： YE ChunXiang 1,LI HongJun 1,ZHU Tong 1,SHANG Jing 1,ZHANG ZeFeng 1,2 & ZHAO DeFeng 1 1 State Key Joint Laboratory of environmental Simulation and Pollution Control college of environmental{3.s and Engineering,Peking university,Beijing 100871,China 2 college of Atmospheric Physics,nanjing university of Information{3. and Technology,nanjing 210044,China 1. State Key Joint Laboratory of environmental Simulation and Pollution Control college of environmental sciences and Engineering Peking University Beijing 100871 China2. College of Atmospheric Physics Nanjing University of Information Science and Technology Nanjing 210044 China

To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015 mol/*** results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (3.%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.

关键词： sea salt particles diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) hydrated water absorbed water reactive uptake coefficient

Relationship Between Vegetation Restoration and Soil Microbial Characteristics in Degraded Karst Regions: A Case Study

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Pedosphere 2011年第1期21卷 132-138页

作者： WEI Yuan YU Li-Fei ZHANG Jin-Chi YU Yuan-Chun D. L. DEANGELIS School of resources and environmental Management Guizhou College of Finance and Economics Guiyang 550004 (China) college of Forestry Guizhou University Guiyang 550025 (China) college of Forest and Environment Nanjing Forestry University Nanjing 210037 (China) Department of Biology University of Maimi P. O. Box 249118 Coral Gables FL 33124 (USA)

The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last *** an attempt to preferably interpret the soil microbiological characteristic variation associated with vegetation restoration and further to explore the role of soil microbiology in vegetation restoration mechanism of degraded karst regions,we measured microbial biomass C and basal respiration in soils during vegetation restoration in Zhenfeng County of southwestern Guizhou Province,*** community level physiological profiles(CLPP) of the soil microbial community to were estimated determine if vegetation changes were accompanied by changes in functioning of soil microbial *** results showed that soil microbial biomass C and microbial quotient(microbial biomass C/organic C) tended to increase with vegetation restoration,being in the order arboreal community stage > shrubby community stage > herbaceous community stage > bare land *** trend was found in the change of basal respiration(BR).The metabolic quotient(the ratio of basal respiration to microbial biomass,qCO 2) decreased with vegetation restoration,and remained at a constantly low level in the arboreal community *** of the CLPP data indicated that vegetation restoration tended to result in higher average well color development,substrate richness,and functional *** utilization of specific substrate guilds was highest in the arboreal community *** component analysis of the CLPP data further indicated that the arboreal community stage was distinctly different from the other three *** conclusion,vegetation restoration improved soil microbial biomass C,respiration,and utilization of carbon sources,and decreased qCO 2,thus creating better soil conditions,which in turn could promote the restoration of vegetation on degraded karst regions.

关键词： basal respiratory community level physiological profile functional diversity metabolic quotient microbial biomass C

Ultrahigh pressure (>7 GPa) gneissic K-feldspar (-bearing) garnet clinopyroxenite in the Altyn Tagh, NW China: Evi- dence from clinopyroxene exsolution in garnet

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science China Earth sciences 2005年第7期48卷 1000-1010页

作者： LIU Liang1,3. CHEN Danling1, ZHANG Anda1, SUN Yong1, WANG Yan1, YANG Jiaxi1,2 & LUO Jinhai1 1. Key Laboratory of Continental Dynamics of the Ministry of Education of China, Northwest university, Xi’an 710069, China 2. college of Earth science and Land{3., Chang’an university, Xi’an 710054, China 3. The Laboratory of Orogen and Basin of the Ministry of Education, Peking university, Beijing 100871, China Key Laboratory of Continental Dynamics Ministry of Education of China Northwest University Xi'an 710069 China Laboratory of Orogen and Basin Ministry of Education Peking University Beijing 100871 China college of Earth science and Land resources Chang'an University Xi'an 710054 China

The exsolution of clinopyroxene and rutile in coarse-grain garnet is found in the gneissic K-feldspar(-bearing) garnet clinopyroxenite from Yinggelisayi in the Altyn Tagh, NW China. The maximum content of the exsolved clinopyroxene in the garnet is up to >5% by volume. The reconstructed precursor garnet (Grt1) before exsolution has a maximum Si content of 3.061 per formula uint, being of supersilicic or majoritic garnet. The peak-stage metamorphic pressure of >7 GPa is estimated using the geobarometer for volume percentage of exsolved pyroxene in garnet and the Si-(Al+Cr) geobarometer for majoritic garnet, and the temperature of about 1000℃ using the ternary alkali-feldspar geothermometer and the experimental data of ilmen- ite-magnetite solid solution. The protoliths of the rocks are intra-plate basic and intermediate ig- neous rocks, of which the geochemical features indicate that they are probably the products of the evolution of basic magma deriving from the continental lithosphere mantle. The rocks are in outcrops associated with ultrahigh pressure garnet-bearing lherzolite and ultrahigh pressure garnet granitoid gneiss. All of these data suggest that the ultrahigh pressure metamorphic rocks in the Altyn Tagh are the products of deep-subduction of the continental crust, and such deep- subduction probably reaches to >200 km in depth. This may provide new evidence for further discussion of the dynamic mechanism of the formation and evolvement of the Altyn Tagh and the other collision orogenic belts in western China.

关键词： Altyn Tagh gneissic K-feldspar (-bearing) garnet clinopyroxenite clinopyroxene exsolution in garnet ultra-high pressure metamorphism.

Effect of Perched Water Tables on Aluminosilicate Stability and Soil Genesis

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Pedosphere 2000年第3期10卷 247-256页

作者： ZHANG MIN , GONG ZITONG and A. D. KARATHANASIS college of resources and Environment, Shandong agricultural{3., Tai’an 271018 (China) Institute of Soil science, the Chinese Academy of sciences, nanjing 210008 (China) college of Agriculture, U asteur.ivic.ve

The mineral stability and solute activities of soil solution extracted from selected horizons of seven studied pedons of Alfisols in Kentucky, USA, and the relationship between distribution of iron-manganese concretions and the restrictive layers were investigated. The results showed that the genesis and development of these soils and mineral weathering trends were strongly influenced by the depth of bedrock and the presence of perched water tables at lithic (limestone) interfaces due to the dissolution and buffering effect of limestone bedrock. The extractable Mg/Ca ratio as depth function and soil depth above bedrock could be used as indices of weathering and degree of soil development. Maximum iron-manganese concretion accumulation was found to occur in the horizon overlying clay horizon (>40% clay) with a sharp increase in clay content (>10%), which suggested that zones of Fe-Mn concretion accumulation in soils of the Inner Bluegrass Region appeared to be a sensitive genetic indicator of argillic horizons with restrictive permeability.

关键词： iron-manganese concretion perched water table soil environment soil genesD

Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

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Chinese Journal of Population,resources and Environment 2005年第4期3卷 20-25页

作者： Wang Geng 1,2 , Nie Baochi 3. Wang Lin 1 & Wu Wei 1 1. School of environmental and Biological science and Technology, Dalian university of Technology, Dalian 116024, China 2. Urban and environmental School, Liaoning Normal university, Dalian 116029, China 3. Shenyang Buraue of Water resources, Shenyang 110013. China. School of environmental and Biological science and Technology Oalian University of Technology Oalian 116024 China Urban and environmental School Uaoning Nonnal University Oalian 116029 China Shenyang Buraue of Water resources Shenyang 110013 China

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.

关键词： the middle and lower reaches of the Liaohe River ecological security assessment indicators system GIS spatial differences