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Citric and Oxalic Acids Effect on Pb and Zn Uptake by Maize and Winter Wheat

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chinese Journal of Population,Resources and Environment 2004年第4期2卷 37-40页

作者： Wang Xinmin, Hou Yanlin & Jie Xiaolei research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china Department of Resource and Environment, Henan Agricultural university, zhengzhou 450002, china. research center for eco-environmental sciences Chinese Academy of Sciences Beijing 100085 China Department of Resource and Environment Henan Agricultural University Zhengzhou 450002 China

A pot experiment was conducted to investigate the influence of citric and oxalic acids effect on Pb and Zn uptake by corn and winter wheat. The experiment was employed with citric acid (CA) applied at 3 rates (0, 1.5 and 3.0 mmol kg-1 soil), oxalic acid (OA) at 3 rates (0, 1.5 and 3.0mmol kg-1 soil) and citric acid combined with oxalic acid (1.5 mmol citric acid combined with 1.5 mmol oxalic acid kg-1). Two types of soil were chose in the experiment. One was collected from the agricultural soil near a battery-recycling factory in Anhui province, china (site A) and the other was collected from a Pb-Zn mine residues in Hunan province, china (site B). The results showed that soil pH varied with the different treatment of citric and oxalic acids. However, there were no differences in all the treatments. 3.0mmol CA kg-1 soil addition significantly increased the concentrations of the CaCI2-extractable Pb and Zn and other treatments have no significantly increased. The highest shoot concentrations of Pb and

关键词： citric acid oxalic acid Pb Zn uptake

Effect of Continuous Vegetable Cultivation on Phosphorus Levels of Fluvo-Aquic Soils

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Pedosphere 2004年第2期14卷 171-176页

作者： WANGXin-Min HOUYan-Lin DepartmentofSoilenvironmentalScience ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085（China）.E-mail：kirk123@***

Soil P status, inorganic P fractions, and P sorption properties were studiedusing sandy fluvo-aquic horticultural soils, which are high in organic matter content for vegetableproduction in comparison with a soil used for grain crop production in zhengzhou, Henan Province,china P fractions, Olsen-P, and OM were determined at different depths in the soil profile andsorption isotherm experiments were performed Most P in excess of plant requirements accumulated inthe topsoil and decreased with soildepth. Total P, inorganic P, and OM concentrations increased withcontinued horticultural use Olsen-P concentrations in the 0-20 cm depth of horticultural soils were9 to 25 times higher than those of the grain crop soil. A linear transformation of the Langmuirequation showed that the P adsorption maximum (491.3 mg P kg^(-1)) and the maximum phosphatebuffering capacity (162.1 L kg^(-1)) for 80--100 cm were greater in the grain crop soil than thehorticultural soils. Thus, the most immediate concern with excess P were in areas where heavy Pfertilizer was used for vegetable crops and where soil P sorption capacities were low due to sandysoils and high organic matter content.

关键词： fractions horticultural soils phosphorus status sorption

ecological hydrograph based on Schizothorax chongi habitat conservation in the dewatered river channel between Jinping cascaded dams

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Science china(Technological sciences) 2011年第S1期54卷 54-63页

作者： LI RuoNan 1,CHEN QiuWen 1,2 & Duan Chen 1,3 1 research center for eco-environmental Science,chinese academy of sciences,beijing 100085,china 2 china Three Gorges university,Yichang 443002,china 3 Hydraulics Department,Changjiang River Scientific research Institute,Wuhan 430010,china 1. research center for eco-environmental Science Chinese Academy of Sciences Beijing 100085 China 2. china Three Gorges university Yichang 443002 China 3. Hydraulics Department Changjiang River Scientific Research Institute Wuhan 430010 China

Hydropower development changes the river hydrological regime,thereby altering river ecosystem *** important measure for reducing degradation of ecosystem is to determine ecological flow and implement it by reservoir *** paper described a method to calculate river ecological flow based on fish habitat conservation and applied it to Jinping River Bend of Yalong *** chongi was selected as target species,and the fish habitat model coupling with water environmental model was developed according to the relationship between fish and water environment ***,improved hydraulic habitat suitability index(IHHS) and habitat fragment index(HFI) varying with discharge were discussed in this *** area representing average annual flow was taken as a reference,and then ecological hydrographs under different habitat conservation levels were calculated considering season variation and life stages of *** to the natural condition,the model results indicated that the reservoir operation clearly influenced the habitat of the target *** was proposed to ensure flow releases to maintain 70%-90% habitat in section after joint while about 60% before joint.

关键词： river habitat habitat assessment ecological flow ecological hydrograph

Landscape ecology：the theoretical foundation of sustainable agrolandscape planning and design

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Journal of environmental sciences 1995年第3期7卷 289-296页

作者： Wang Yanglin(Department of Geography, Peking university, beijing 100871 , china)Fu Bojie(research center for eco-Environrnental Sceiences, chinese Acaderny of sciences, beijing 100085, china)

Ｌａｎｄｓｃａｐｅｅｃｏｌｏｇｙ：ｔｈｅｔｈｅｏｒｅｔｉｃａｌｆｏｕｎｄａｔｉｏｎｏｆｓｕｓｔａｉｎａｂｌｅａｇｒｏｌａｎｄｓｃａｐｅｐｌａｎｎｉｎｇａｎｄｄｅｓｉｇｎ．ＷａｎｇＹａｎｇｌｉｎ（Ｄｅｐａｒｔｍｅｎｔｏ... 详细信息

Ｌａｎｄｓｃａｐｅｅｃｏｌｏｇｙ：ｔｈｅｔｈｅｏｒｅｔｉｃａｌｆｏｕｎｄａｔｉｏｎｏｆｓｕｓｔａｉｎａｂｌｅａｇｒｏｌａｎｄｓｃａｐｅｐｌａｎｎｉｎｇａｎｄｄｅｓｉｇｎ．ＷａｎｇＹａｎｇｌｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＧｅｏｇｒａｐｈｙ，Ｐｅｋｉｎｇ...

关键词： landscape ecology sustainable development agrolandscape sustainabillty.

Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley

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Science china Earth sciences 2008年第7期51卷 1021-1035页

作者： LIU YunYun1,2,3 & DING YiHui2 1 chinese academy of Meteorological sciences, beijing 100081, china 2 National Climate center, beijing 100081, china 3 Graduate university of chinese academy of sciences, beijing 100049, china 1. chinese academy of Meteorological sciences Beijing 100081 China 2. National Climate center Beijing 100081 China 3. Graduate university of chinese academy of sciences Beijing 100049 China

Based on the Indian and chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern china. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South china Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion

关键词： Indian summer monsoon (ISM) the Meiyu over the Yangtze River Valley teleconnection mode

ecological rebuilding and land reclamation in surface mines in Shanxi Province, china

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Journal of environmental sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2, GAO Lin 1 (1. research center for eco environmental sciences, chinese academy of sciences, beijing 100085, china E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi Agricultural university Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in china. As land is under pressure in china, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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Science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG XiaoChao1,2↑ & WANG ShiJin1 1 center for Space Science and Applied research, chinese academy of sciences, beijing 100190, china 2 Graduate university of chinese academy of sciences, beijing 100049, china 1. center for Space Science and Applied research Chinese Academy of Sciences Beijing 100190 China 2. Graduate university of chinese academy of sciences Beijing 100049 China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2004, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2005 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2·srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 26-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

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 academy of sciences,beijing 100101,china 2 Department of economics and Management,Zhejiang Forestry university,Linan 311300,china 3 center for chinese Agricultural Policy,chinese academy 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,soil 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

Effects of elevated CO_2 on growth and carbon partitioning in rice

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chinese Science Bulletin 1998年第23期43卷 1982-1986页

作者： LIN Weihong\+1 and WANG Dali\+2 1. Department of Plant Nutrition, china Agricultural university, beijing 100094, china 2. Department of Systems ecology, research center for eco_environmental Science, chinese academy of sciences, beijing 100085, china Department of Plant Nutrition China Agricultural University Beijing China Department of Systems ecology Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing China

Rice (\%Oryza sativa\% cv. Jindao 1187) was grown in open_top chambers which contained ambient and enriched CO\-2. CO\-2 elevation stimulated rice tillering during early vegetative stage. However, panicle dry weight per plant did not change at maturity stage. Root biomass was enhanced by high CO\-2. Root / shoot ratio was increased under high CO\-2 at maturity, indicating more carbon allocation to the below_bround part in rice under high CO\-2.

关键词： CO 2 elevation growth carbon partitioning rice (\%Oryza sativa cv\%. Jindao 1187).