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Biomass estimation and uncertainty analysis based on CBERS-02.CCD camera data and field measurement

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Science China(Technological sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2. GAO Yanhua1,3. CHENG Yu1,3. WEI Zheng1,3. XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 100101, China 2. {3.graphy and Environment {2., Jiangxi Normal university, Nanchang 3.002., China 3. Graduate university of Chinese Academy of sciences, Beijing 10003., China 4. Beijing Research Institute of Uranium {3.logy, Beijing 100875, China 5. Institute of {3.graphic sciences and Natural resources Research, Chinese Academy of sciences, Beijing 100101, China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China geography and Environment college Jiangxi Normal University Nanchang 330027 China Graduate university Chinese Academy of Sciences Beijing 100039 China Beijing Research Institute of Uranium geology Beijing 100875 China Institute of geographic sciences and Natural {2. Research Chinese Academy of Sciences Beijing 100101 China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02.satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02.CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02.CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

Growth of Carbon Encapsulated Long Nickel Nanorods on Bulk Nickel Substrate

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Journal of Wuhan university of Technology(Materials Science) 2011年第1期26卷 28-32页

作者：宾晓蓓 college of resources & Environment Engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 3. nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3. LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of geographic sciences and Natural {2. Re-search, Chinese Academy of sciences, Beijing 100101, China 2. Institute of Forestry, Chinese Academy of Forestry sciences, Beijing 100091, China 3. Department of Civil Engineering, university of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of sciences, Beijing 100085, China 5. college of {2. and Environment, Southwest Agricultural university, Chongqing 400716, China Correspondence should be addressed to Chen Hao Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Forestry Chinese Academy of Forestry Sciences Beijing China Department of Civil Engineering University of Hong Kong Hong Kong China Eco-environmental Research Center Chinese Academy of Sciences Beijing China college of resources and Environment Southwest Agricultural University Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 53. mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 3.%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel

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Science China(Technological sciences) 2004年第4期47卷 488-504页

作者： LIU Yan1,3. LIU Zhilin1, ZHANG Chengwei1,2.& ZHOU Yingchun1 1. Liaoning Institute of Technology, Jinzhou 12.001, China 2. China National Oil and Gas Exploration and Development Corporation, Beijing 100011, China 3. {3. of Science, Northeastern university, Shengyang 110006, China Liaoning Institute of Technology Jinzhou China college of Science Northeastern University Shengyang China China National Oil and Gas Exploration and Development Corporation Beijing China

This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond n A with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference απ Using n A, S, απ we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.

关键词： valence electron structure, sulfide, hot brittleness, and rare earth.

South China's Gondwana connection in the Paleozoic:Paleomagnetic evidence

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Progress in Natural Science:Materials International 2004年第1期14卷 86-91页

作者： ZHANG Shihong*(School of earth sciences and {2., China {3. of geosciences, Beijing 100083. China) China Univ geosci Sch Earth Sci & Resources Beijing 100083 Peoples R China

The reconstruction in which the South China Block (SCB) lies along the Great India Australia region of Gondwana margin is tested by using existing Paleozoic paleomagnetic data. Under the proposed reconstruction, all six high quality paleopoles from the SCB between the Early Cambrian and late Early Devonian (～400 Ma) are in good agreement with coeval paleopoles from Gondwana. Thereafter, the apparent polar wander paths for the SCB and Gondwana diverge markedly. This indicates that the SCB had been part of Gondwana and the connection was intact from at least Early Cambrian until late Early Devonian, but they began to separate by late Middle Devonian (～3.5 Ma).

关键词： South China block Gondwana paleomagnetism reconstruction

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science China earth sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. LI Xiubin2.& ZHANG Ming2.1. Institute of Remote Sensing & GIS, Peking {3., Beijing 100871, China 2. Institute of geographical {2. and Natural resources Research, Chinese Academy of {2., Beijing 100101, China Institute of Remote Sensing & GIS Peking University Beijing China Institute of geographical sciences and Natural {2. Research Chinese Academy of Sciences Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

Relationship between surface subsidence factor and mining depth of strip pillar mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 594-598页

作者： GUO Wen-bing1, 2. HOU Quan-lin 1, ZOU You-feng2.1. college of {3. Science, Graduate {2. of Chinese Academy of sciences, Beijing 100049, China 2. School of Energy Science and Engineering, Henan Polytechnic {2., Jiaozuo 454000, China college of earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Energy Science and Engineering Henan Polytechnic University Jiaozuo 454000 China

Strip pillar mining is one of the most important technical measures to control mining subsidence in China. Mining depth is one of the most important factors that can affect the mining subsidence in strip pillar mining. Six numerical simulation models were set up to simulate the surface subsidence of strip pillar mining in different mining depths. The mining depth in these six models ranges from 3.0 to 800 m. The simulated results were compared and analyzed. The formula was established based on the simulated results. It demonstrated that the subsidence of strip pillar mining method is related to mining depth. While the other conditions are the same, the subsidence of strip pillar mining increases with the increase of mining depth by logarithmic relationship.

关键词： subsidence factor strip pillar mining mining depth numerical simulation

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science China earth sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2. XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4 1. Faculty of earth Science and State Key Laboratory of geological Processes and Mineral {2., China university of geosciences, Wuhan 43.074, China 2. Institute of {2. & Environments, Henan Polytechnic university, Jiaozuo 454003. China 3. Department of Computer Science, South-Central university for Nationalities, Wuhan 43.074, China 4. Laboratory of Marine geology, Tongji university, Shanghai 2.0092. China China university of geo{2. Henan Polytechnic university South-Central university for Nationalities Tongji university

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?2..3. (‰ V-PDB) to ?2..14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2.3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02. to 0.2.%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.2. to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South China, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2. climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South China.

Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit,Southeastern Hubei Province

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矿物学报 2009年第S1期29卷 314-316页

作者： LI Jian-wei 1,2.DENG Xiao-dong1,2.ZHOU Mei-fu3.LIU Yong-sheng1(1. State Key Laboratory of geological Processes and Mineral {3.,China {2. of geosciences,Wuhan 43.074,China 2. Faculty of earth {3.,China {2. of geosciences,Wuhan 43.074,China 3. Department of earth sciences,the {2. of Hong Kong,Hong Kong)

Titanite(CaTi2.iO5) is an important accessory mineral not only in magmatic and metamorphic rocks,but also commonly in hydrothermal mineral deposits. It incorporates appreciable amounts(usually 10×10-6 s to 100×10-6 s) of U and Th into its structure and has a closure temperature of Pb diffusion higher than 660～700 ℃(Scott and St-Onge,1995) ,making it an ideal U-Th-Pb geochronometer. The Daye metallogenic district is located in the west of the giant Middle-Lower Yangtze River(MLYR) Cu-Fe-Au province,eastern China and is well endowed with Fe,Cu,and polymetallic skarn deposits.

关键词： Pb Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit,Southeastern Hubei Province Th Fe ICP Cu MS