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Impacts of population growth and economic development on the nitrogen cycle in asia

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Science China(Life Sciences) 2005年第z2期48卷 729-737页

作者： ZHU Zhaoliang XIONG Zhengqin XING Guangxi State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

asia is the major consumer of fertilizer nitrogen and energy in the world, and consequently shares a considerable proportion of the world creation of reactive nitrogen (Nr). However, if estimated on per capita basis, asia is characterized by a lower arable land area, fertilizer nitrogen consumption, energy consumption, and gross domestic product, as well as lower daily protein intake. To meet the increasing needs for food and energy for the growing population combined with the improvement of living standards, Nr will inevitably increase. The present study estimates the creation of Nr and the emissions of various N compounds into environment in asia currently and in 2030. In comparison with the world averages, the lower fertilizer nitrogen and energy use efficiencies, and the lower use of animal wastes for agriculture imply that there is potential for moderating the increase in Nr and its impacts on the environment. Strategies for moderating the increase are discussed.

关键词： reactive nitrogen, asia, regional variation, environment, nitrogen flux.

DISTRIBUTIONS OF SULFUR POLLUTANTS IN EAST asia

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Chinese Geographical Science 2000年第1期10卷 39-44页

作者： Hui-wang Gao Mei-yuan Huang Jun-ling An asteur.ivic.ve

A Eulerian sulfur deposition model is used to study the distributions of sulfur pollutants in East asia, in which important physical and chemical processes such as transport, diffusion, dry and wet deposition, vertical transportation in cumulus cloud, gas phase chemistry, aqueous phase chemistry and heterogeneous aerosol chemistry are included. Two cases, the periods of 1987.07.02 GMT00-1987 07 03 GMT00(case 1) and 1989 04 20 GMT00-1989 04 21 GMT00(case 2), are studied and the distributions of SO 2 and SO 2- 4 in East asia are shown. It is revealed that the patterns of distributions of SO 2 and SO 2- 4 are different under different meteorological conditions. In the upper layer, the concentrations of SO 2 and SO 2- 4 are 0.4-1.0?μg/m 3 and 0.2-0.5?μg/m 3, 4.0-10.0?μg/m 3 and 2.0-6.0?μg/m 3 in the middle layer. In the surface layer, the levels of SO 2 range from 4.0 to 30.0?μg/m 3 and from 2.0 to 8.0?μg/m 3 for SO 2- 4. Distributions of SO x are controlled by emissions in the surface layer, while in the upper layer it is mainly affected by precipitation. The distributions of SO x show the interaction of emissions, winds and precipitation in the middle layer.

关键词： sulfur pollutants deposition model East asia, sulfur distribution

Forest carbon budgets in Southeast asia following harvesting and land cover change

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Science China(Life Sciences) 2002年第z1期45卷 55-64页

作者： Rodel D. Lasco Environmental Forestry Programme University of the Philippines College 4031 Laguna Philippines

Terrestrial ecosystems play an important role in the global carbon (C)cycle. Tropical forests in Southeast asia are constantly changing as a result of harvesting and conversion to other land cover. As a result of these changes, research on C budgets of forest ecosystems has intensified in the region over thelast few years. This paper reviews and synthesizes the available information. Natural forests in SE asia typically contain a high C density (up to 500 Mg/ha). Logging activities are responsible for at least 50% decline in forest C *** deforestation (conversion from forest to grassland or annual crops) results in C density of less than 40 Mg/ha. Conversion to tree plantations and other woody perennial crops also reduces C density to less than 50% of the originalC forest stocks. While much information has been generated recently, there are still large gaps of information on C budgets of tropical forests and its conversion to other land uses in SE asia. There is therefore a need to intensify research in this area.

关键词： carbon budgets, tropical forests, Southeast asia, land cover change.

Mesozoic subduction-accretion zone in northeastern South China Sea inferred from geophysical interpretations

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Science China Earth Sciences 2006年第5期49卷 471-482页

作者： ZHOU Di1, WANG Wanyin2, WANG Jialin3, PANG Xiong4, CAI Dongsheng5 & SUN Zhen1 1. Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guang- zhou 510301, China 2. College of Geological and Topographical Engineering, Chang’an University, Xi’an 710054, China 3. Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China 4. China National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, China 5. China National Offshore Oil Co. Limited – Research Center, Beijing 100027, China 1. Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. College of Geological and Topographical Engineering Chang’an University Xi’an 710054 China 3. Key Laboratory of Marine Geology Tongji University Shanghai 200092 China 4. China National Offshore Oil Co. Limited — Shenzhen Branch Shenzhen 518067 China 5. China National Offshore Oil Co. Limited — Research Center Beijing 100027 China

A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South China Sea at approximately NE450 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in sizeand intensity to that of the Manila subduction-accretion zone. A belt of high positive magneticanomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arcassociated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and presentseafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally byNW-running strike-slip faults, in concord with the Mesozoic stress field of South China. Inaddition, the existence of the subduction zone is supported by wide-angle seismic data obtained indifferent years by different institutions. At approximate localities, a north-dipping ramp of Mohosurface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 kmbeneath the Moho reflector is indicated by both OBS and long-cable seismic records. Theidentification of a segment of Mesozoic subduction zone in NE South China Sea fills nicely the gapof the Great Late Mesozoic Circum SE asia Subduction-acrretion Zone, which extended from Sumatra,Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan.

关键词： Mesozoic, subduction zone, SE asia, NE South China Sea, geophysics.

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth Sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2. Department of Urban and Resources Sciences, Nanjing University, Nanjing 210093, China 3. Department of Earth Sciences, Nanjing University, Nanjing 210093, China 4. Department of Geography, Shaanxi Normal University, Xi’an 710062, China 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 6 Department of Geography, Qinghai Normal University, Xining 810008, China 7. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of Sciences Beijing 100039 China 2. Department of Urban and Resources Sciences Nanjing University Nanjing 210093 China 3. Department of Earth Sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of asia, the middle Miocene.

Effects of China＇s Structural Change on the Exports of East asian Economies

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China & World Economy 2017年第3期25卷 1-30页

作者： Hyun-Hoon Lee Donghyun Park Kwanho Shin Professor International Trade and Business Kangwon National UniversityKorea Principal Economist Economic Research and Regional Cooperation Department Asian Development Bank. Professor Economics Department Korea University

The Chinese economy is slowing down and is in the midst of a structural transJormattonfrom export-led and investment-led growth to domestic demand-led and consumption-ledgrowth. While there are widespread concerns among China＇s trading partners about theeffect of the slowdown in China＇s growth on their exports, China＇s structural changes arealso likely to have a significant impact：for example, China will import fewer machinesand more cosmetics. The central objective of the present paper is to empirically examinethe effect of China＇s structural transformation on the exports of East asian economies,which have close trade linkages with China. We find that economies that have failed toincrease the share of consumption goods in their exports to China have suffered largerdeclines in their quantities of exports to China. In addition, economies that have sufferedlosses in their shares of China＇s parts and components imports have faced reductions intheir shares in China ＂s total imports.

关键词： China, East asia, export, global value chain, structural change