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The Early Triassic Helongshan Formation in Anhui,China:Record of the Triassic Biotic Recovery in the Lower Yangtze Region

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地学前缘 2009年第S1期16卷 254-254页

作者： Liwei Zhang~(1,2),Zhihai Jia~3,Fumei Yang~1,Jinlong Xu~1 1.School of resources and environmental Engineering,Hefei University of Technology,Hefei 230009,China. 2.institute of resources and environment,Henan Polytechnic University,Jiaozuo 454000,China 3.School of Chemical and Biomolecular Engineering,University of Sydney,Sydney NSW2006,Australia

The Lower Triassic is well outcropped in central and southern Anhui Province,East China,and it consists of the Yinkong,Helongshan and Nanlinghu Formations in an ascending *** Helongshan Formation belonging to the Smithian has been well studied in this project because of the typical sedimentary features and different fossil types which are not similar to the lower Yinkeng Formation or

关键词： sedimentary characteristics biotic recovery Early Triassic Helongshan Formation

Ecological Footprint and Ecological Security Evaluation in the Upper Min River Basin

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Wuhan University Journal of Natural Sciences 2005年第4期10卷 641-646页

作者： TU Jian-jun 1, 2 1. School of resources and environment Science, Southwest China Normal University, Chongqing 400715, China 2. institute of Mountain Hazards and environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China Southwest China Normal University School of Resources and Environment Science Chongqing China (GRID:grid.263906.8) Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***)

On the basis of the ecological footprint (EF) model, this paper studied theecological security in the Upper Min River Basin ecosystem. The result shows that with 2. 038 2 hm^2per capita ecological capacity (0. 422 2 hm^2 higher than per capita EF) ,and 165 825 hm^2 ecologysurplus , the ecosystem in Upper Min River is generally secure at present. But the arable land isoverweighed and omens an eco-security crisis. Meanwhile, problems such as low forest coverage rate,severe loss of water and soil,enlargement of arid-valley area, frequent occurrence of mountainhazards and degradation of pastures have been major threats to the eco-security of this region. Thecalculation result of ten-thousand-yuan ( RMB) GDP shows that the use of natural resources isextensive, and there will be a rapid increase tendency of EF in the future. In order to maintain thepresent eco-security, the ways of use natural resources must be improved in the Upper Min RiverBasin.

关键词： ecological security ecological footprint ecological capacity quantitativeevaluation the Upper Min River Basin

Endolithic fungi:A possible killer for the mass extinction of Cretaceous dinosaurs

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Science China Earth Sciences 2008年第6期51卷 801-807页

作者： GONG YiMing1,2, XU Ran1 & HU Bi2 1 Key Laboratory of Biogeology and environmental Geology of Ministry of Education, State Key Laboratory of Geological Processes and Mineral resources, China University of Geosciences, Wuhan 430074, China 2.institute of resources and environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province, Henan Polytechnic University, Jiaozuo 454003, China 1. Key Laboratory of Biogeology and environmental Geology of Ministry of Education State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. institute of resources and environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province Henan Polytechnic University Jiaozuo 454003 China

Mycelium-like structures found under ESEM within radial sections of fragmental dinosaur eggshells would be the endolithic fungi coexistent with dinosaur eggs in the upper part of the Late Cretaceous Hugang Formation from the Wenjiaping section of Wenxian, Danjiangkou, northwestern Hubei, Central China. The endolithic fungi selectively occurred in the bad biomineral zone within the columnar layer of the eggshells, where the crowded endolithic fungi penetrated the columnar layer at near-vertical or near-horizontal angles. The endolithic fungi are needle-like, ribbon-like and silk-like, and 5–18 μm long, 0.3–0.5 μm wide at their base, with pointed tip, and are unbranched. The hyphae are mainly composed of oxygen, carbon and calcium, and are with minor sodium, potassium, chlorine and sulfur. The endolithic fungi and host have the same characters in lithification, fracture and main chemical composition. We suggested that the episode endolithic fungi invading dinosaur eggs may have taken place in the interval between after formation of dinosaur eggshells and before their petrification and that dinosaur eggs invaded by endolithic fungi would not be normally incubated or would only be incubated into venerable and pathologic baby dinosaurs to be easily to aborted and contributed to the mass extinction of the dinosaurs at the end of Cretaceous.

关键词： endolithic fungi dinosaur eggs mass extinction Cretaceous

Operation Performance of Central Solar Heating System with Seasonal Storage Water Tank in Harbin

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湖南大学学报（自然科学版） 2009年第S1期36卷 111-114页

作者： YE Ling1,JIANG Yi-qiang1,YAO Yang1,ZHANG Shi-cong2(1.institute of Heat Pump and Air Conditioning Technology,Harbin institute of Technology,Harbin,Heilongjiang 150090,China 2.institute of Built environment and Energy Efficiency,China Academy of Building Research,Beijing 100013,China) institute of Heat Pump and Air Conditioning Technology Harbin Institute of Technology Harbin 150090 China institute of Built environment and Energy Efficiency China Academy of Building Research Beijing 100013 China

This paper presented a preliminary research on the central solar heating system with seasonal storage(CSHSSS)used in cold climate in China.A mathematical model of the solar energy seasonal storage water tank used in the central solar heating system was firstly developed based on energy *** was followed by the simulation of the CSHSSS used in a two-floor villa in Harbin,and analysis of the impacts on storage water temperature of tank volume,solar collector area,tank burial depth,insulation thickness around the tank,*** results show there is a relatively economical tank volume to optimize the system efficiency,which decreases with increasing tank volume at the constant collector area,and increases with increasing collector area at the constant tank ***,the insulation thickness has obvious effect on avoiding heat loss,while the tank burial depth doesn'*** addition,the relationship between the solar collector efficiency and storage water temperature is also obtained,it decreases quickly with increasing storing water temperature,and then increases slowly after starting space heating *** may be helpful for relevant design and optimization in cold climates in China and all over the world.

关键词： central solar heating system with seasonal storage(CSHSSS) simulation system efficiency storage water tank villa

Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

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Science China Earth Sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1,2,LIN XueHui1,2,YAO De3,4 & GUO WeiDong5 1 Key Laboratory of Marine Oil and Gas resources and Marine environment,Ministry of Land and resources,Qingdao 266071,China 2 Qingdao institute of Marine Geology,China Geological Survey,Qingdao 266071,China 3 institute of resources and environment,Shandong University of Technology,Zibo 255049,China 4 institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China 5 Department of Oceanography,Xiamen University,Xiamen 361005,China 1. Key Laboratory of Marine Oil and Gas resources and Marine environment Ministry of Land and Resources Qingdao 266071 China2. Qingdao Institute of Marine Geology China Geological Survey Qingdao 266071 China3. Institute of Resources and Environment Shandong University of Technology Zibo 255049 China4. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China5. Department of Oceanography Xiamen University Xiamen 361005 China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2 combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4＋ by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

On Post-Shear-Instability in Saturated Soils

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地学前缘 2009年第S1期16卷 262-263页

作者： Xiaobin Lu~1,Xuhui Zhang~2 1.institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,China. 2.institute of Mountain Hazard and environment,Chinese Academy of Sciences,Chengdu China,

The study on the development of shear band is very import since it is the main reason of landslide. According to experimental results,there is only one shear band forming at last when the soil specimen beard shear loa... 详细信息

关键词： shear band landslide finite amplitude disturbances

Combining Ridge with No-Tillage in Lowland Rice-Based Cropping System: Long-Term Effect on Soil and Rice Yield

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Pedosphere 2009年第4期19卷 515-522页

作者： JIANG Xian-Jun2 and XIE De-Ti College of resources and environment, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716 (China) [a]College of resources and environment Southwest University 216 Tiansheng Road Beibei Chongqing 400716 (China)

A tillage method of combining ridge with no-tillage (RNT) was employed in lowland rice-based cropping system to study the long-term effects of RNT on soil profile pattern, soil water stable aggregate distribution, nutrients stratification and yields of rice and post-rice crops. After flooded paddy field (FPF) was practiced with RNT for a long time, soil profile changed from G to A-P-G, and horizon G was shifted to a deeper position in the profile. Also the proportion of macroaggregate (> 2 mm) increased, whereas the proportion of silt and clay (2003 and 2006 when serious drought occurred. RNT was proven to be a better tillage method for lowland rice-based cropping system.

关键词： aggregate-size distribution conservative tillage flooded paddy field soil profile pattern

Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin

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Pedosphere 2005年第5期15卷 53-58页

作者： YUAN Fei 1,2, XIE Zheng-Hui1,* 2, LIU Qian1 and XIA Jun 3 1LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 (China). 2 College of Water resources and environment, Hohai University, Nanjing 210098 (China)3 institute of Geographical Science & Natural resources, Chinese Academy of Sciences, Beijing 100101 (China) institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 （China）. 2 College of Water resources and environment Hohai University Nanjing 210098 （China）3 institute of Geographical Science & Natural resources Beijing 100101 （China）

Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.25° × 0.25° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2 (1991-2100) and future climateB2 (1991-2100) with A2 and B2 being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2 and B2, theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 2031-2070. In addition,under future climate A2 and B2, an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin.

关键词： climate change regional climate modeling system runoff VIC-3L model

Assessing and regulating the impacts of climate change on water resources in the Heihe watershed on the Loess Plateau of China

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Science China Earth Sciences 2010年第5期53卷 710-720页

作者： LI Zhi1,2, LIU WenZhao2, ZHANG XunChang3 & ZHENG FenLi2 1 College of resources and environment, Northwest Agriculture & Forestry University, Yangling 712100, China 2.institute of Soil and Water Conservation, Chinese Academy of Sciences & Ministry of Water resources, Yangling 712100, China 3 USDA-ARS Grazinglands Research Laboratory, 73036, El Reno, Oklahoma, USA 1. College of resources and environment Northwest Agriculture & Forestry University Yangling 712100 China2. Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources Yangling 712100 China3. USDA-ARS Grazinglands Research Laboratory El Reno Oklahoma 73036 USA

Climate change can cause considerable changes in water resources and assessing the potential impacts can provide important information for regional sustainable development. The objectives were to evaluate the possible impacts of climate change during 2010-2039 on water resources (runoff, soil water content, and evapotranspiration) in the Heihe watershed on the Loess Plateau of China and to further explore adaptive measures to cope with the changes. Projections of four climate models (CCSR/NIES, CGCM2, CSIRO-Mk2, and HadCM3) under three emission scenarios (A2, B2, and GGa) were used to estimate future changes in precipitation, maximum and minimum temperature based on Change Factor method. The Soil and Water Assessment Tool (SWAT) was employed to simulate the hydrologic responses to climate changes. The CA-Markov model was used to develop land use scenarios. Compared with the present climate, the climate models predicted a -2.3% to 7.8% change in annual precipitation, 0.7 to 2.2°C rises in maximum temperature, and 1.2 to 2.8°C rises in minimum temperature. Without consideration of land use change, SWAT predicted a -19.8% to 37.0% change for runoff, -5.5% to 17.2% change for soil water content, and 0.1% to 5.9% increase for evapotranspiration during 2010–2039 under all climate scenarios. Though the change of hydrometeorolocial variables are complex, they would possibly increase with great probability, and the hydrological regime would be influenced such as a decrease in runoff in winter months. With land use changes, the projected land use of 2015 would increase soil water content by 4.0% and surface runoff by 5.7% while slightly decrease evapotranspiration by 0.6% compared with the 2000 land use. This result showed that adjustment of land use patterns was capable of regulating water resources and could be used to mitigate the adverse effects of climate change.

关键词： climate change water resources SWAT the Loess Plateau