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Soil carbon pool in china and its global significance

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Journal of environmental sciences 1996年第2期8卷 249-254页

作者： Fang Jingyun, Liu Guohua, Xu Songling(research center for eco-environmental Science, chineseacademy of sciences, beijing 100085, china) Res. Ctr. for eco-Environ. Science Chinese Academy of Sciences Beijing 100085 China

Soil organic carbon density and its related characteristics of 41 soil types all over china were analyzed by using data of 745 soil profiles , and size of soil carbon pool was estimated. As a result, area-weighted averages of these 41 soil types for bulk density, profile depth, organic carbon content and profile carbon were 1. 24 tC/m3, 86. 2 cm, 3. 04% and 19. 7 kg C/m2 respectively. Total size of soil carbon pool was 185. 68 × 1009tC, which is 29 times of that in terrestrial biomass of china and 12. 6% of global soil carbon pools. Because of its huge carbon pool, soil of china plays an important role in global carbon cycle.

关键词： china global climate change soil carbon content soil carbon pool soil type.

Characteristics of distribution of heavy metals insediment of Le An River

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Journal of environmental sciences 1995年第2期7卷 240-245页

作者： Li Qi (research center for eco - environmental sciences,chinese academy of sciences , beijing 100085 , china)Chen Shiming (Nanchang Institute of Aeronautical Technology . Nanchang 330034 , china) A. Yahya (Institute for Sedimentology, University of Heid Rsch Ctr for eco-Envmtl Sci Chinese Academy of Sciences Beijing China China

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关键词： Heavy metals sedirnent pollution.

Wavelet Analysis of the Schwabe Cycle Properties in Solar Activity

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chinese Journal of Astronomy and Astrophysics 2004年第6期4卷 578-582页

作者： Gui-Ming LeNational Astronomical Observatories, chinese academy of sciences, beijing 100012 center for Space Science and Applied research center, chinese academy of sciences, beijing 100080 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 []Center for Space Science and Applied Research Center Chinese Academy of Sciences Beijing 100080

Properties of the Schwabe cycles in solar activity are investigated by using wavelet transform. We study the main range of the Schwabe cycles of the solar activity recorded by relative sunspot numbers, and find that the main range of the Schwabe cycles is the periodic span from 8-year to 14-year. We make the comparison of 11-year’s phase between relative sunspot numbers and sunspot group numbers. The results show that there is some difference between two phases for the interval from 1710 to 1810, while the two phases are almost the same for the interval from 1810 to 1990.

关键词： sun sunspot sun activity method data analysis

Toxicokinetics and the related metabolites in rainbow trout(Oncorhynchus mykiss) after exposure to decabromodiphenyl ether

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Science china Chemistry 2010年第11期53卷 2379-2386页

作者： FENG ChengLian,XU YiPing,ZHA JinMiao,LUO Qian,SHAN XiaoQuan & WANG ZiJian State Key Laboratory of environmental Aquatic Chemistry research center for eco-environmental sciences,chinese academy of sciences,beijing 100085,china 1. State Key Laboratory of environmental Aquatic Chemistry research center for eco-environmental sciences Chinese Academy of Sciences Beijing 100085 China

Decabromodiphenyl ether(BDE209) is poorly absorbed by mammals,and little information is available on the toxicokinetics of BDE209 and its metabolites in *** the present study,rainbow trout(Oncorhynchus mykiss) were administered to 100 ng/g and 500 ng/g body wet weight of BDE209 via a single intraperitoneal injection and parent BDE209 and its metabolites were sequentially monitored for 28 *** results showed that toxicokinetic profiles of BDE209 could be described by the one-compartment *** the higher dose group(500 ng/g wet weight),the calculated half-life(t1/2) and elimination rate(ke) were 17.7 d and 0.039/d in the liver,and 100.3 d and 0.007/d in the muscle,*** major methoxylated brominated diphenyl ethers(MeO-BDEs) were detected with 2,2',4,4'-tetrabromo-5-methoxydiphenyl ether(5-MeO-BDE47) being detected in all tissue *** was no significant temporal change of 5-MeO-BDE47 concentration in the muscle,whereas an exponential increase was observed in the ***,the metabolism rate of BDE209 depended on the administered ***209 was hardly accumulated in the muscle of rainbow trout,while the liver was a primary metabolic ***-BDEs were formed via metabolism of BDE209,which probably played a significant role in fish toxicology as a potential indicator.

关键词： decabromodiphenyl ether(BDE209) polybrominated diphenyl ethers(PBDEs) methoxylated brominated diphenyl ethers(MeO-BDEs) toxicokinetics rainbow trout

Decrease trend of dust event frequency over the past 200 years recorded in the Malan ice core from the northern Tibetan Plateau

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chinese Science Bulletin 2005年第24期50卷 2866-2871页

作者： WANG Ninglian Key Laboratory of Cryosphere and environment, Cold and Arid Regions environmental and Engineering research Institute, chinese academy of sciences, Lanzhou 73000, china Institute of Tibetan Plateau research, chinese academy of sciences, beijing 100085, china Key Laboratory of Cryosphere and environment Cold and And Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 73000 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

By analyses of the dust layers in the Malan ice core from the northern Tibetan Plateau, it was found that dirty ratio in this core might be a good proxy for dust event frequency. The variations in the dirty ratio displayed a de- crease trend over the past 200 years, which implies that dust events became less frequent during the study period. The decrease trend in the variations in dust event frequency might be caused mostly by the natural processes, including increasing precipitation and weakening westerly which might be related with global warming. Furthermore, significant negative correlation was found between the dirty ratio and δ 18O in the Malan ice core. This is highly important for studying the effect of atmospheric dust on climate change.

关键词：青藏高原马伦冰核气候变化扬尘事件发生频率

Heavy metal adsorption on the Le An River sediment —The adsorption model

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Journal of environmental sciences 1997年第1期9卷 59-70页

作者： Wen Xianghua Du Oing Tang Hongxiao research Centre for eco-environmental sciences,chinese academy of sciences.beijing 100085,china Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

In this study,the surface properties and adsorption properties of the Le An River sedi- ment were modelled via surface complexation *** model parameters were determined based on the data of our potentiometric titration experiments and the metal adsorption experiments with the Le An River sediment ***,the surface complexation models for the natural sediment,in our case the Le An River sediments,which can interpret the experimental data very well were successfully *** typical surface complexation models that is the con- stant capacitance model,the diffuse layer model and the triple layer model,were considered in this *** work indicated that the consistency and the interdependency among model parame- ters together with the selection of the surface adsorbed species should be emphasized.

关键词： surface complexation model Le An River sediment potentiometric titration adsorption.

Nitrogen, phosphorus and potassium recycling in an agroforestry ecosystem of Huanghuaihai Plain: with Paulownia elongata intercropped wheat and maize as an example

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Journal of environmental sciences 1998年第2期10卷 62-69页

作者： Wu Gang Department of Systems ecology,research center for eco environmental sciences, chinese academy of sciences,beijing 100085,china

The studies show that in the whole community, P is deficient, and N and K are basically balanced. N, P and K are accumulated in plant tissues and litters, but depleted in soil. N and P contents in surface soil(0—20 cm) are the main factors affecting crop growth, and P contents in 20 80 cm soil layer is the major affecting Paulownia elongata growth. The absorption coefficients of N, P and K in the communities are 0 078, 0 014 and 0 052 respectively, their utilization coefficients are 0 95, 0 90 and 0 94, and the recycling coefficients are 0 042, 0 05 and 0 063 respectively.

关键词： nitrogen phosphorus, potassium recycling agroforestry ecosystem.

Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science china(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied ecology, chinese academy of sciences, Shenyang 110016, china School of Forestry, Northeast Forestry University, Harbin 150040, china State Key Lab of Systems ecology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china Graduate University of chinese academy of sciences, beijing 100039, china 1. Institute of Applied ecology Chinese Academy of Sciences Shenyang 110016 China 2. School of Forestry Northeast Forestry University Harbin 150040 China 3. State Key Lab of Systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate University of chinese academy of sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2%, much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

From economic prosperity to ecological sustainability──A theoretical and practical concern of sustainable development in china

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Journal of environmental sciences 1994年第4期6卷 389-401页

作者： Wang Rusong, Hu DanReseareh center for eco-environmental sciences,chinese,chineseacademy of Seiences, beijing 100085.china

china. a country with more than 1. 2 billion people, is undergoing a rapid industrializationand urbanization. While brings wealth and hopes to people, the economic prosperity has to pay the priceof the ecological degradation. What kind of dynamics and cybernetics is needed to lead a sustainabledevelopment and ecological health? How to deal with the complicated relationships between social transi-tion , economic growth and environmental change? This article is to present some theoretical and practicalconcerns from the viewpoint of human system ecology with some cases of small towns in the coastal areaof china.

关键词： sustainable development economic prosperity ecological sustainability china