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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. {3. 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 {2.s 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. 03. 2.hm^2.er capita ecological capacity (0. 42. 2.hm^2.higher than per capita EF) ,and 165 82. 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

Effect of Combined Heavy Metal Pollution on Nitrogen Mineralization Potential,Urease and Phosphatase Activities in a Typic Udic Ferrisol

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Pedosphere 1999年第3期9卷 251-258页

作者： ZHENG CHUNRONG TU CONG and CHEN HUAIMAN(Laboratory of Material Cycling in Pedosphere, institute of soil {2., the {3. academy of {2.s,nanjing 2.0008 (china))(Received April 2., 1999 revised June 2. 1999) 中科院南京土壤所江苏南京 210008 中科院南京土壤所江苏南京

Individual and combined effects of Cu, Pb, Zn and Cd on N mineralization, urease and phosphatase were examined in a Typic Udic Ferrisol in laboratory by employing an uniform design and a single factor *** pollution caused by heavy metals inhibited N mineralization (No value) and urease and phosphatase activities. The combined pollution of metals alleviated their toxicity to N mineralization to some extent,whereas aggravated the toxicity to urease and phosphatase. Phosphorous application could mitigate the toxic effect of heavy metals on phosphatase activities, while alleviating effect of N application on the toxicity of heavy metals to urease was inconsistent. However, the mitigating effect of the fertilizers was limited in heavily polluted soils.

关键词： heavy metal pollution N mineralization phosphatase urease

Monitoring the concentration of N_2. in the Fildes Peninsula, maritime Antarctica

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chinese science Bulletin 2000年第21期45卷 2000-2004页

作者： SUN Liguang, XIE Zhouqing, ZHAO Junlin, XING Guangxi, SHI Shulian & Du Lijuaninstitute of Polar Environment, University of science and Technology of{2., Hefei 2.3}02.,{2. institute of Environmental science, Beijing Normal University, Beijing 100875,{2. Laboratory of Material Cycling in Pedosphere, institute of soil science, chinese {12. of sciences, {13. 2.10008,{2. institute of Polar Environment University of Science and Technology of China Hefei China institute of Environmental science Beijing Normal University Beijing China Laboratory of Material Cycling in Pedosphere Institute of Soil Science Chinese Academy of Sciences Nanjing China

Gases in the marine boundary layer in Fildes Peninsula, maritime Antarctica were sampled and analyzed for the first time. Sampling sites included areas covered by moss and lichen growth, penguin colonies and an area where scientific research stations are located. A total of 2.1 samples were analyzed for N2. concentrations, with an average of (3.1.3.±3.07) nL/L. This is above the global average value of 3.4 nL/L. It is found that the N2. concentrations evidently increase during the summer months. Concentrations around the research stations are higher than at remote areas, indicating a potential source from human activities on the island. N2. concentrations at a large penguin colony on Barton Peninsula are the highest among the sampled areas. This may explain why N2. concentrations in Fildes Peninsula are higher than the global average. Our preliminary conclusions are that human activities and emissions from penguin dropping-amended soil and vegetation soil constitute the major sources of N2. in the

关键词： Antarctica Fildes Peninsula N2. soil penguin dropping.

The Suitability of Using Leaf Area Index to Quantify soil Loss under Vegetation Cover

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Journal of Mountain science 2011年第4期8卷 564-570页

作者： ZHANG Wentai YU Dongsheng SHI Xuezheng WANG Hongjie GU Zhujun ZHANG Xiangyan TAN Manzhi State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 21o0o8 China Graduate University of the chinese academy of {2.s Beijing 100039 China School of Bio-Chemical and Environmental Engineering Nanjing Xiaozhuang University Nanjing 211171 China

soil erosion by water under forest cover is a serious problem in southern china.A comparative study was carried out on the use of leaf area index(LAI) and vegetation fractional coverage(VFC) in quantifying soil loss under vegetation *** types of vegetation with varied LAI and VFC under field conditions were exposed to two rainfall rates(40 mm h-1 and 54 mm h-1) using a portable rainfall *** rate,sediment concentration and soil loss rate were measured at relatively runoff stable *** negative exponential relationship(p 2.= 0.83. and linear relationship(p 2.= 0.84) were obtained between LAI and sediment concentration,while no significant relationship existed between VFC and sediment *** mechanism by which vegetation canopy prevents soil loss was by reducing rainfall kinetic energy and sediment *** could better quantify such a role than ***,neither LAI nor VFC could explain runoff rate or soil loss *** must be taken when using LAI to quantify the role of certain vegetation in soil and water conservation.

关键词： Leaf area index(LAI) Runoff steady state Sediment concentration Simulated rainfall

Evaluation of N2.Fixing Capacities of Herbaceous and Shrub Legumes Under Field Condition

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Pedosphere 1998年第1期8卷 33-36页

作者： XING GUANGXI SHI SHULIAN CAO YACHENG DU LIJUAN SUN GUOQING and ZHOU KEYU(institute of soil {2., the {3. academy of {2.s, nanjing 2.0008 (china)) institute of soil {2. Chinese Academy of Sciences Nanjing 210008 China

Natural 15N abundance method was used in this study to investigate the N2.fixing capacities of several herbaceous and shrub legumes by a field experiment. For herbaceous legumes, the results were in consistent with those obtained by a pot experiment. Crotalaria mucronata Desv. had a higher N2.fixing capacity than Vigna sinensis (L.) Savi. For shrub legumes, N2.fixing capacity under field condition was slightly different from that in pot experiment. These results demonstrated that the natural 15N abundance method was applicable to evaluating N2.fixing capacities of herbaceous and shrub legumes, and that pot experiment was suitable for evaluating the N2.fixing capacities of not only herbaceous legumes but also shrub *** N2.fixing plants differed in response to phosphorus fertilization. Phosphorus fertilizer application greatly increased the percentage of nitrogen derived from air (% N dfa) and total amount of N2.fixed by Lespedeza formosa (Vog.) Koehne (Jiangxi). Phosphorus fertilizer showed no significant effect on the N2.fixing percentage of Cajanus cajan (L.) Millsp. but increased its total biomass, thus increasing the total amount of N2.fixed.

关键词： herbaceous legumes natural 15N abundance method N2.fixing capacity shrub legumes

Effect of Lanthanum on Major Microbial Populations in Red soil

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Pedosphere 2001年第1期11卷 73-76页

作者： CHU HAIYAN, WANG JUNHUA, XIE ZUBIN, ZHU JIANGUO, LI ZHENGAO and CAO ZHIHONG (institute of soil {2., the {3. academy of {2.s, nanjing 2.0008 (china)) 中科院南京土壤所江苏南京 210008

Pure culture and pot culture experiments were carried out to study the effect of lanthanum (La) on bacteria, actinomyces and fungus, and some microbial physiological groups , nitrifier, azotobacter and phos- phobacteria, in a red soil taken form the Ecological Experimental Station of Red soil, the {2. {3. of sciences, Jiangxi Province. LaCl3.was added into media at levels of 0, 2., 50, 100, 150, 2.0, 2.0 and 500 mg L-1 in the pure culture experiment, and into soil samples in porcelain pots before rice growing at levels of 0, 6, 3., 150, 3.0, 600 and 900 mg kg-1 dry soil in the pot culture experiment. The populations of the three soil microbes in the pure culture experiment decreased with the addition level of La, indicating that La was toxic to the soil microbes in pure culture, and the sensitivity of the 3.major microbial types to La was in a decreasing order of actinomyces > bacteria > fungus. In the pot experiment, La had slightly stimulative effect on soil bacteria and actinomyces when applied at low concentrations while had inhibitory effect on soil bacteria, actinomyces and fungus at high concentrations. When the concentration of La was low, soil azotobacter was stimulated slightly while soil nitrifier was stimulated strongly and the maximum increase was up to 50%. When the concentration of La was high, both soil azotobacter and nitrifier were inhibited, and the inhibition of La to the nitrifier increased with La concentration. La added at all the levels had stimulative effect on soil inorganic and organic phosphobatteria. Among the 4 physiological groups, soil nitrifier was most sensitive to La, so , it might be reasonable to assume that soil nitrifier was a sensitive indicator for evaluating the biological and environmental effects of rare earths.

关键词： lanthanum microbial populations physiological groups rare earths red soil

Sustainable Nutrient Management in chinese Agriculture: Challenges and Perspective

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Pedosphere 2006年第2期16卷 253-263页

作者： GAO Chao SUN Bo ZHANG Tao-Lin Department of Geography Nanjing University Nanjing 210093 （China）. institute of soil {2. Chinese Academy of Sciences Nanjing 2100（78 （China）

china has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented.

关键词： china food security nutrient management soil fertility water quality

Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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science china Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2.3.HUANG JiKun 1,3.& DENG XiangZheng 1,3.1 institute of Geographic sciences and Natural Resources Research,chinese {3. of sciences,Beijing 100101,china 2.Department of Economics and Management,Zhejiang Forestry University,Linan 3.13.0,china 3.Center for chinese Agricultural Policy,chinese {3. of sciences,Beijing 100101,china 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,{2. and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

Surface N Balances in Agricultural Crop Production Systems in china for the Period 1980-2.15

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Pedosphere 2008年第3期18卷 304-315页

作者： SUN Bo SHEN Run-Ping A. F. BOUWMAN Institate of soil science Chinese Academy of Sciences Nanjing 210008 （China） nanjing University of Information science and Technology Nanjing 210044 （China） National institute for Public Health and the Environment P. O. Box 303 3720 AH Bilthoven （The Netherlands）

Surface nitrogen （N） balances for china＇s crop production systems was estimated using statistical data collected from 1980 to 2.04 at the national and provincial scale and from 1994 to 1999 at the county level. There was a surplus N balance throughout these periods, but the surplus was nearly stable in recent years. Projections using nonseasonal Box-Jenkins model or exponential models show that the N surplus for the total cultivated land in china was likely to increase from 142.8 kg ha^-1 in 2.04 to 168.6 kg ha 1 in 2.15. The N balance surplus in the more developed southeastern provinces was the largest, and was slightly less in the central region, which caused the nitrate pollution in the ground water. The N surplus was much less in the western and northern provinces because of lower synthetic fertilizer inputs. The region with high N risk includes Beijing Municipality and Jiangsu, Zhejiang, Fujian, Guangdong, Hubei, and Shandong provinces for 2.02.2.04. The projections suggested that 15 provinces （or municipalities） in the middle and southeastern part of china except Jiangxi and Shanxi provinces would become the high-risk region by 2.15. The level of economic development, transportation, and labor force condition had an important effect on the N balance surplus at the county level, but the last two factors showed remarkable impact at the provincial level. To decrease the nonpoint pollution （Npp） risk from crop production, the authors suggested to reduce the target level for national grain self-sufficiency to 90%-95% and change the regional structure of grain production by moving some of the future grain production from the high Npp risk areas of eastern china to parts of the central and western provinces where the Npp risk was much less.

关键词： agriculture china driving force nonpoint pollution risk surface nitrogen balance