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Evolutionof Sustainable Carbon Cycling Processes in china

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chinese Journal of Population,Resources and Environment 2004年第2期2卷 4-10页

作者： Zhuang Yahui, Zhang Hongxun,Wang Xiaoke & Fang Jinyunresearch center for {2.-environmental sciences(RCEES),chinese academy of sciences,PO Box 2.71,Beijing 100085,chinadepartment of Urban ecology,Peking University ,Beijing 100871,china research center for {2.-environmental sciences (RCEBS) Chinese Academy of Sciences PO Box 2871 Beijing 100085 China department of Urban ecology Peking University Beijing 100871 China

This report summarizes the surveys on carbon inventories and initiatives on sustainable carbon cycling taken by RCEES. The first part of this report deals with the concept of sustainable carbon cycling, the historical evolution of carbon cycling processes in china, carbon pool enhancement, value addition, carbon sequestration and carbon balance. The second part covers the modeling of carbon dynamics, emission inventories of various carbon containing greenhouse gases and their potential abatement measures.

关键词： sustainable development carbon cycle carbon pool carbon sequestration

Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW china

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Journal of Mountain science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Urban and Regional ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Centre for Hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern china. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.

关键词： Vertical distribution of land cover Anthropogenic activity Vegetation activity environmental variability china

Mineral Coated Fertilizer Effect on Nitrogen-Use Efficiency and Yield of Wheat

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Pedosphere 2005年第4期15卷 526-531页

作者： LI Jian-Yun HUA Quan-Xian TAN Jin-Fang ZHOU Jian-Min HOU Yan-Lin L department of Soil environmental {2. Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 （China）. State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the chinese academy of sciences Beijing 100039 （China） College of Agriculture Henan Agricultural University Zhengzhou 450002 （China）

A field experiment with winter wheat （Triticum aestivurn L.） was conducted on a silt loam calcaric endorusti-ustic Cambosols derived from the Yellow River alluvial deposits in Henan, china, from 2.01 to 2.02.to evaluate N recovery and agronomic performance of different mineral coated fertilizers （MiCFs） compared to normal urea used in wheat cropping {2. under field conditions. Five treatments, including CK （check, no N fertilizer）, urea and three different MiCFs at an equivalent N application rate were established in a randomized complete block design. N release from MiCFs in soil was more synchronous with the N requirement of wheat throughout the growth stages than that from urea, with grain yield of the MiCF treatments significantly higher （P 〈 0.05） than that of the treatment urea. Correspondingly, the N recovery rate was greater for all MiCFs compared to urea, increasing from 32.8% up to 50.1%. Due to its high recovery and low cost, use of the mineral coated N fertilizers was recommended instead of the polymer coated N fertilizers.

关键词： mineral coated fertilizer N recovery urea winter wheat

CONGRATULATIONS TO ACADEMICIAN JUNZHI CUI ON HIS 70^(th) BIRTHDAY

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Journal of Computational Mathematics 2008年第3期26卷 259-260页

作者： Institute of Computational Mathematics and Scientific/Engineering Computing academy of Mathematics and systems {2. chinese academy of sciences Institute of Computational Mathematics and Scientific/Engineering Computing academy of Mathematics and systems {2. chinese academy of sciences

Professor Junzhi Cui was born on June 15, 1938 in Xinxiang, Henan Province in china. He graduated from the department of Mathematics and Mechanics, Northwestern Polytechnic University in 1962. Since then, he has been ... 详细信息

关键词： BIRTHDAY CONGRATULATIONS TO ACADEMICIAN JUNZHI CUI ON HIS 70 th HIS

Carbon Dioxide Fluxes and Concentrations in a Cotton Field in Northwestern china:Effects of Plastic Mulching and Drip Irrigation

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Pedosphere 2011年第2期21卷 178-185页

作者： LI Zhi-Guo Key Laboratory of Oasis ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy ofSciences Urumqi 830011 (China) Graduate University of chinese academy of sciences Beijing 100049 (China) Institute of Soil science Chinese Academy of Sciences Nanjing 210008 (China) Earth System science Interdisciplinary center University of Maryland College Park MD 20740 (USA)

In northwestern china, there has been a change from traditional cultivation system （TC） with no mulching and flood irrigation to a more modern cultivation system （MC） using plastic film mulching with drip irrigation. A field study was conducted to compare soil ＇C02.concentrations and soil surface COs fluxes between TC and MC systems during a cotton growing season. CO2.concentrations in the soil profile were higher in the MC system （3107-92.2.L L-1） than in the TC system （1 2.5-8994 μL L-1） but the rate of CO2.flux was lower in the MC system. Possible reasons for this included decreased gas diffusion and higher soil moisture due to the mulching cover in the MC system, and the consumption of soil CO2.by weathering reactions. Over the whole cotton growing season, accumulated rates of CO2.flux were 300 and 394 g C m-2.for the MC and TC systems, respectively. When agricultural practices were converted from traditional cultivation to a plastic film mulching system, soil CO2.emissions could be reduced by approximately 100 g C m-2.year-1 in agricultural lands in arid and/or semi-arid areas of northern and northwestern china.

关键词： agricultural practice carbon cycle greenhouse gas emission soil respiration weathering reaction

pH effect of· OH radical induced oxidation of phosphoryl- methionine in aqueous solution

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chinese science Bulletin 1997年第4期42卷 296-301页

作者： CHUGaosheng, YAO Side, ZHANG Zhicheng, ZHANG Manwei and WANG Wenfeng1.department of Applied Chemistry, University of science and Technology of{2., Hefei 2.002.,{2. 2.Shanghai Institute of Nuclear research, chinese academy of sciences, Shanghai 2.1800,{2. department of Applied Chemistry University of Science and Technology of China Hefei China Shanghai Institute of Nudear research Chinese Academy of Sciences Shanghai China

STUDIES of radiation chemistry on methionine (Met) were very active in previous years because of its actions of radioprotection to biological systems by quenching·OH radicals. On the other hand, people have paid more and more attention to the researches on the phosphorylation of the biological polymolecules. It is wall known that phosphate ester is regarded as the deposi-

关键词： pulse radiolysis NDM a-amino radical pH effect.

A virtual reference satellite differential method for relative correction of satellite ephemeris errors

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science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2300-2306页

作者： CAI ChengLin 1,3 , LI XiaoHui 2.3 & WU HaiTao 2.3 1 Gulin University of Electronic Technology, 541004, china 2.National Time Service center,{2., Lintong 710600, china 3 Key Laboratory of Precision Navigation and Timing Technology, National Time Service center,{2., Lintong 710600, china 1. Gulin University of Electronic Technology Gulin 541004 China3. Key Laboratory of Precision Navigation and Timing Technology National Time Service Center Chinese Academy of Sciences Lintong 710600 China2. National Time Service Center Chinese Academy of Sciences Lintong 710600 China

In order to solve the problems that the novel wide area differential method on the satellite clock and ephemeris relative correction (CERC) in the non-geostationary orbit satellite constellation, a virtual reference satellite (VRS) differential principle using relative correction of satellite ephemeris errors is proposed. It is referred to be as the VRS differential principle, and the elaboration is focused on the construction of pseudo-range errors of VRS. Through qualitative analysis, it can be found that the impact of the satellite’s clock and ephemeris errors on positioning can basically be removed and the users’ positioning errors are near zero. Through simulation analysis of the differential performance, it is verified that the differential method is universal in all kinds of satellite navigation systems with geostationary orbit (GEO) constellation, Medium orbit (MEO) constellation or hybrid orbit constellation, and it has insensitivity to abnormal aspects of a satellite ephemeris and clock. Moreover, the real time positioning accuracy of differential users can be maintained within several decimeters after the pseudo-range measurement noise is effectively weakened or eliminated.

关键词： wide area differential method virtual reference satellite (VRS) satellite ephemeris errors satellite clock errors constellation

Integrating landscape ecological principles and land evaluation for sustainable land use

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Journal of environmental sciences 1999年第2期11卷 9-13页

作者： Fu Bo jie, Chen Li ding research Centre for eco {2. sciences, chinese academy of sciences, Beijing 100085, china He Chan sheng department of Geography, Western Michigan University, Kalamazoo, MI 49008, USA

Many existing methods for appraisal of agricultural areas and farming systems are short of dynamics and spatial analysis. The main objective of this paper is to merge approaches in classical land evaluation, largely based on soil science, and newer approaches in landscape {2., which are rather based on the relationships between spatial patterns (physiography, land use and farming system design, vegetation etc.) and processes (farming activities, scale changes, geomorphological processes, bio ecological processes). Rapid changes in rural areas have an impact on both processes and patterns. Planning for sustainable use of these areas should include the assessment of the interrelations between these patterns and processes.

关键词： landscape pattern ecological process land evaluation land sustainable use.

Applications of stable isotopes to study plant-animal relationships in terrestrial ecosystems

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chinese science Bulletin 2004年第22期49卷 2339-2347页

作者： WANG Jianzhu1,LIN Guanghui1,2.HUANG Jianhui1 & HAN Xingguo1 1.Key Laboratory of Quantitative Vegetation sciences and research {2. for Plant ecology and Biodiversity Conservation,Institute of Botany,chinese academy of sciences,Beijing 100093,china 2.department of Global ecology,Carnegie Institution of Washington,Stanford,CA 94305,USA Key Laboratory of Quantitative Vegetation sciences and research {2. for Plant ecology and Biodiversity Conservation Institute of Botany Chinese Academy of Sciences Beijing 100093 China department of Global ecology Carnegie Institution of Washington Stanford CA 94305 USA

As natural tracers, stable isotopes have been extensively used in plant physiological, ecological and envi- ronmental research. Recently, animal physiological ecologists have also applied stable isotope techniques to study plant- animal relationships. The isotopic compositions of animal body generally reflect and integrate their diets over a time period ranging from hours to years to the lifetime of an indi- vidual. When animal living habitat changes or animals move to a new environment, the animal isotopic compositions will shift accordingly. Thus, stable isotope signatures of an ani- mal can truly reflect its food sources, habitat, distribution and movement patterns during a given time period. More- over, by analyzing animal-tissue isotopic compositions at different temporal scales, we can improve our understanding of animal adaptation to environmental changes. Stable iso- tope technique also provides an ideal tool to study animal foodweb relationship and community structure because of isotopic fractionation during the processes of nutrient as- similation by animals. Stable isotope technique can continu- ously measure animal trophic position in a foodweb, which can eventually reveal the predator-prey relationship and its role in determining matter balance and energy flow in the entire ecosystem. Stable isotope technique has been one of the most important and efficient tools in studying plant-animal relationship. In this paper, we first review recent advances in the application of stable isotope techniques to plant-animal relationship research then evaluate their advantages and disadvantages, and finally discuss some future directions associated with stable isotope applications to plant-animal relationship research.

关键词：稳定同位素植物-动物关联性食物来源营养水平动物迁移