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Change of surface cover greenness in China between 2000 and 2010

Chinese science Bulletin 2012年第22期57卷 2835-2845页

作者： LIU Shuang1,4& GONG Peng1,2,31State Key Laboratory of Remote Sensing science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of sciences,and Beijing Normal university, Beijing 100101, China 2Institute for Global Change Studies & Center for Earth System science, Tsinghua university, Beijing 100084, China 3.epartment of environmental science, policy and management, university of california, berkeley, ca94720, usa 4Graduate university of Chinese Academy of sciences, Beijing 100049, China State Key Laboratory of Remote Sensing science Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate university of Chinese Academy of sciences Beijing China Institute for Global Change Studies & Center for Earth System science Tsinghua University Beijing China Department of environmental science Policy and Management University of California Berkeley USA

Surface greenness reflects the situation of vegetation *** index calculated from the Red and Near Infrared bands of remote sensing images,whose values indicate the level of photosynthetic activity,is monotonically related to surface greenness when vegetation canopy does not fully cover the background *** for desert regions,vegetation index is positively correlated with vegetation ***,vegetation index can be used to study the change in greenness of desert *** study collected MODIS Normalized Difference Vegetation Index (NDVI) data from 2000 to 2010 and analyzed their change over China in this *** results showed that an increasing trend of NDVI occurred over 66.84% (OLS fitting) or 64.27% (LAD fitting) of China,indicating that China's greenness is increasing ***,desertification of China *** showing large increase in greenness are found in Shaanxi,Shanxi,Ningxia,Henan,Shandong,Qinghai,and Gansu while regions with large decrease in greenness are found in Northeast Inner Mongolia,South Tibet,Jiangsu,and *** of Qinghai,Gansu,Xinjiang and South Tibet could probably be driven by climate *** of greenness in Northeast Inner Mongolia was related to agricultural *** of greenness in Jiangsu and Shanghai was related to rapid *** factors did not exhibit obvious correspondence to the large increase in greenness in Shaanxi,Shanxi,Ningxia and Gansu,indicating that the changes might have been caused by human *** reduction of desert areas in China could probably have been caused by human management and protection at the national scale.

关键词：中国地表覆盖归一化植被指数植被覆盖度沙漠地区 NDVI 西藏南部气候因素

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Macroscopic relationship for preferential flow in the vadose zone:Theory and validation

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science China(Technological sciences) 2009年第11期52卷 3264-3269页

作者： LIU HuiHai1 & ZHANG RenDuo2 1 Earth science Division, Lawrence berkeley National Laboratory, berkeley, ca 947200, usa 2 School of environmental science and Engineering, Sun Yat-sen university, Guangzhou 510275, China Earth science Division Lawrence Berkeley National Laboratory Berkeley CA 947200 USA School of environmental science and Engineering Sun Yat-sen University Guangzhou 510275 China

Preferential flow commonly observed in unsaturated soils allows rapid movement of solute from the ground surface or vadose zone to the groundwater, bypassing a significant volume of unsaturated soil and increasing the risk of groundwater contamination. A variety of evidence indicates that complex preferential flow patterns observed from fields are fractals. This paper discusses a macroscopic relationship for modeling preferential flow in the vadose zone. Conceptually, the flow domain can be divided into active and inactive regions. Flow occurs preferentially in the active region (characterized by fractals), and inactive region is simply bypassed. The portion of the active region was found to be a power function of saturation. The validity of this macroscopic relationship is demonstrated by its consistency with field observations and the related numerical experiments.

关键词： preferential flow constitutive relations vadose zone hydrology

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Principle of small target detection for hyperspectral imagery

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science China Earth sciences 2007年第8期50卷 1225-1231页

作者： GENG XiuRui1,2,3 & ZHAO YongChao2,3,4 1 Research Center for Remote Sensing and GIS, Department of Geography, Beijing Normal university, Beijing 100875, China 2 State Key Laboratory of Remote Sensing science, Chinese Academy of sciences, Beijing 100101, China 3 Institute of Erectronics, Chinese Academy of sciences, Beijing 100080, China 4 Center for for Assessment and Monitoring of Forest and environmental Resources and Division of Ecosystem sciences university of california berkeley, ca 94720-3114, usa 1. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing science Chinese Academy of Sciences Beijing 100101 China 3. Institute of Erectronics Chinese Academy of Sciences Beijing 100080 China 4. Center for for Assessment and Monitoring of Forest and environmental Resources and Division of Ecosystem sciences University of California Berkeley CA 94720-3114 USA

This paper generalizes the progress of algorithms in small target detection for hyperspectral imaging, and finds that whitening the image is the key point of many methods in small target detection. An al-gorithm is presented to detect desired targets by converting large targets into small ones based on the weighted sample autocorrelation matrix.

关键词： hyperspectral whiten target detection

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Measurement of Thermal Expansion Coefficients with Holographic Technique

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Journal of Thermal science 1995年第1期4卷 67-74页

作者： Zhifeng Zhang(Department of Mechanical and environmental Engineering, university of california at Santa Barbara, ca93106, usa) Department of Mechanical and environmental Engineering University of California at Santa Barbara USA

A simplified mathematical model was created for measurement of thermal expansion coefficients of thinsheet materials with holographic technique. Experimental set-ups corresponding to the mathematicalmodel were designed and built for both tests above room temperature and at low temperatures. Afringe control technique was introduced for low temperature measurements to compensate rigid bodymovement. Thin sheet specimens of silicon and aluminum alloy (7075) were tested with the developedtechnique. The tested results are in good agreement with reported data and thus verify the validityof the developed technique. The thermal expansion coefficients of the tested materials ranged from2.5×10-6C-1 to 23.6×0-60C-1.

关键词： thermal expansion holographic measurement low temperature tests deformation tests.

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A Spectral Index for Estimating Soil Salinity in the Yellow River Delta Region of China Using EO-1 Hyperion Data

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Pedosphere 2010年第3期20卷 378-388页

作者： WENG Yong-Ling GONG Peng ZHU Zhi-Liang Department of Surveying and Mapping Engineering College of Transportation Southeast University Nanjing 210096(China) State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications of the Chinese Academy ofSciences and Beijing Normal University Beijing 100101 (China) Department of Environment science Policy and Management University of California Berkeley CA 94720 (USA) EROS Data Center U.S. Geological Survey Sioux Falls SD 57198 (USA)

Soil salinization is one of the most common land degradation processes. In this study, spectral measurements of saline soil samples collected from the Yellow River Delta region of China were conducted in laboratory and hyperspectral data were acquired from an EO-1 Hyperion sensor to quantitatively map soil salinity in the region. A soil salinity spectral index (SSI) was constructed from continuum-removed reflectance (CR-reflectance) at 2052 and 2203 nm, to analyze the spectral absorption features of the salt-affected soils. There existed a strong correlation (r = 0.91) between the SSI and soil salt content (SSC). Then, a model for estimation of SSC with SSI was established using univariate regression and validation of the model yielded a root mean square error (RMSE) of 0.986 and an R2 of 0.873. The model was applied to a Hyperion reflectance image on a pixel-by-pixel basis and the resulting quantitative salinity map was validated successfully with RMSE = 1.921 and R2 = 0.627. These suggested that the satellite hyperspectral data had the potential for predicting SSC in a large area.

关键词： hyperspectral reflectance soil salt content spectral absorption features

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Characteristics of Phosphorus in Some Eastern Australian Acid Sulfate Soils

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Pedosphere 2002年第3期12卷 229-234页

作者： C. LINSchool of environmental science and management, Southern Cross university, Lismore, NSW (Australia) Schoolofenvironmentalscienceandmanagement SouthernCrossUniversityLismoreNSW(Australia)

Forty-five acid sulfatc topsoil samples (depth < 0.5 m) from 15 soil coreswere collected from 11 locations along the New South Wales coast, Australia. There was an overalltrend for the concentration of the HCl-extract... 详细信息

Forty-five acid sulfatc topsoil samples (depth cations along the New South Wales coast, Australia. There was an overalltrend for the concentration of the HCl-extractable P to increase along with increasing amounts oforganic C and the HCl-extractable trivalent metals in the topsoils of some less-disturbed acidsulfate soils (pH cal cycling and was retained by complexation with trivalent metals or their oxides andhydroxides. While there was no clear correlation between pH and the water-extractable P, theconcentration of the water-extractable P tended to increase with increasing amounts of theHCl-extractable P. This disagrees with some established models which suggest that the concentrationof solution P in acid soils is independent of total P and decreases with increasing acidity. Thehigh concentration of sulfate present in acid sulfate soils appeared to affect the chemical behaviorof P in these soil systems. Comparison was made between a less disturbed wetland acid sulfate soiland a more intensively disturbed sugarcane acid sulfate soil. The results show that reclamation ofwetland acid sulfate soils for sugarcane production caused a significant decrease in theHCl-extractable P in the topsoil layer as a result of the reduced bio-cycling of phosphorusfollowing sugarcane farming. Simulation experiment shows that addition of hydrated lime had noeffects on the immobilization of retained P in an acid sulfate soil sample within a pH range3.5～4.6. When the pH was raised to above 4.6, soluble P in the soil extracts had a tendency toincrease with increasing pH until the 15th extraction (pH 5.13). This, in combination with the poorpH-soluble P relationship observed from the less-disturbed acid sulfate soils, suggests that solubleP was not clearly pH-dependent in acid sulfate soils with pH < 4.5.

关键词： acid sulfate soil acidity phosphorus

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Analytical Methods for environmental Risk Assessment of Acid Sulfate Soils: A Review

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Pedosphere 2001年第4期11卷 301-310页

作者： C. LIN School of environmental science and management, Southern Cross university, Lismore, NSW (Australia) Southern Cross university 澳大利亚

Assessment of acid sulfate soil risk is an important step for acid sulfate soil management and its reliability depends very much on the suitability and accuracy of various analytical methods for estimating sulfide-derived potential acidity, actual acidity and acid-neutralizing capacity in acid sulfate soils. This paper critically reviews various analytical methods that are currently used for determination of the above parameters, as well as their implications for environmental risk assessment of acid sulfate soi1s.

关键词： acid risk assessment acid sulfate soils analytical methods

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Scenario simulation and forecast of land use/cover in northern China

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3 & HE ChunYang 3 1 College of Geographical science, Chongqing Normal university, Chongqing 400047, China 2 College of Resources and environmental science, Chongqing university, Chongqing 400044, China 3 College of Resources science & Technology, Beijing Normal university, Beijing 100875, China College of Geographical science Chongqing Normal University Chongqing 400047 China College of Resources and environmental science Chongqing University Chongqing 400044 China College of Resources science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (ca) model is developed with land use/cover scenario changes in northern China in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-ca model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and ca. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in ca model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern China.

关键词：土地利用中国北方细胞自动机系统动力学

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A Lipidomic Study of the Effects of N-methyl-N′-nitro-N-nitrosoguanidine on Sphingomyelin Metabolism

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Acta Biochimica et Biophysica Sinica 2005年第8期37卷 515-524页

作者： Yun HUANG~(&#) Jing SHEN~# Ting WANG Yan-Ke YU Fanqing E CHEN~1 Jun YANG~* Department of Pathology and Pathophysiology,Center for environmental Genomics Zhejiang university School of Medicine,Hangzhou 310031,China ~1 Molecular Biology Branch.Life science Division,Lawrence berkeley National Laboratory,university of california at berkeley,berkeley,ca 94720,usa Department of Chemistry,Georgia State university.Atlanta,GA 30303.usa DepartmentofPathologyandPathophysiology CenterforEnvironmentalGenomicsZheJiangUniversitySchoolofMedicineHang

Systems biology is a new and rapidly developing research area in which,by quantitativelydescribing the interaction among all the individual components of a cell,a systems-level understanding of abiological response can be ***,it requires high-throughput measurement technologies forbiological molecules,such as genomic and proteomic approaches for DNA/RNA and protein,***,a new concept,lipidomics,which utilizes the mass spectrometry(MS)method for lipid analysis,has been *** this lipidomic approach,the effects of N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)on sphingomyelin metabolism,a major class of sphingolipids,were *** moleculeswere extracted from cells and analyzed by matrix-assisted laser desorption ionization-time of flight *** found that MNNG induced profound changes in sphingomyelin metabolism,including the appearance ofsome new sphingomyelin species and the disappearance of some others,and the concentrations of severalsphmgomyelin species also *** was accompanied by the redistribution of acid sphingomyelinase(ASM),a key player in sphingomyelin *** the other hand,imipramine,an inhibitor of ASM,caused the accumulation of *** also prevented some of the effects of MNNG,as well as theredistribution of *** together,these data suggested that the lipidomic approach is highly effectivefor the systematic analysis of cellular lipids metabolism.

关键词： lipidomics mass spectrometry ceramide sphingomyelin acid sphingomyelinase

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Interaction mechanisms of organic contaminants with burned straw ash charcoal

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Journal of environmental sciences 2010年第10期22卷 1586-1594页

作者： Wenhai Huang,Baoliang Chen Department of environmental science,Zhejiang university,Hangzhou 310028,China [a] Department of environmental science Zhejiang University Hangzhou 310028 China

Black carbons （e.g., charcoal） have a great impact on the transport of organic contaminants in soil and water because of its strong affinity and ubiquity in the environment. To further elucidate their interaction mechanism, sorption of polar （p-nitrotoluene, m-dinitrobenzene and nitrobenzene） and nonpolar （naphthalene） aromatic contaminants to burned straw ash charcoal under different de-ashed treatments were investigated. The sorption isotherms fitted well with Freundlich equation, and the Freundlich N values were all around 0.31-0.38, being independent of the sorbate properties and sorbent types. After sequential removal of ashes by acid treatments （HCl and HCl-HF）, both adsorption and partition were enhanced due to the enrichment of charcoal component. The separated contribution of adsorption and partition to total sorption were quantified. The effective carbon content in ash charcoal functioned as adsorption sites, partition phases, and hybrid regions with adsorption and partition were conceptualized and calculated. The hybrid regions increased obviously after de-ashed treatment. The linear relationships of Freundlich N values with the charring-temperature of charcoal or biochar （the charred byproduct in biomass pyrolysis） were observed based on the current study and the cited publications which included 15 different temperatures （100-850℃）, 10 kinds of precursors of charcoal/biochar, and 10 organic sorbates.

关键词： ash charcoal organic pollutant adsorption partition effective carbon

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