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Variation of karst spring discharge in the recent five decades as an indicator of global climate change: A case study at Shanxi, northern China

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Science China Earth Sciences 2005年第11期48卷 2001-2010页

作者： GUO Qinghai1, WANG Yanxin1, MA Teng1 & LI Luxiu2.1. School of environmental studies, China University of Geosciences, Wuhan 430074, China 2. Office of Water Resource Management of Shanxi Province, Taiyuan 030001, China 1. School of environmental studies China University of Geosciences 430074 Wuhan China 2. Office of Water Resource Management of Shanxi Province 030001 Taiyuan China

Karst in Shanxi Province is representative of that in northern China, and karst water systems discharge in the form of springs that are among the most important sources for local water supply. Since the 1950s, attenuation has been the major trend of discharge variation of most karst springs at Shanxi. Based on the case study of 7 karst springs including Niangziguan, Xin’an, Guozhuang, Shentou, Jinci, Lancun, and Hongshan springs, the discharge variation process of karst springs was divided into natural fluctuation phase and anthropogenic impact phase. Discharge attenuation of the 7 karst springs was controlled mainly by climate and human activities, with their contributions being respectively about 60% and 40%. According to the dif-ference of the effect of climate and human activities for each spring, attenuation modes of spring discharge fall into three types: natural process dominated attenuation type, exploitation induced process dominated attenuation type, and mixed attenuation type. The total restored discharge variation of 7 karst springs matched well with the global air temperature change in 1956―2.00, clearly indicating the trend of global warming and aridity in the last several decades, and the analysis of discharge variation processes of karst springs can be used as a new tool for global change studies.

关键词： karst, Shanxi, spring discharge, attenuation, climate, human activity, global change

Debating about the climate warming

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Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： WANG Shaowu1, LUO Yong2. ZHAO Zongci2. DONG Wenje2.and YANG Bao3 (1.Department of Atmospheric Sciences, School of Physics, Peking University, Beijing 100871, China 2. Laboratory for Climate studies, China Meteorological Administration, Beijing 100081, China 3. Institute of Cold and Arid Regions environmental and Engineering, Chinese Academy of Sciences, Lanzhou 730000, China) [a] Department of Atmospheric Sciences School of Physics Peking University Beijing China [b] Laboratory for Climate studies China Meterological Administration Beijing China [c] Institute of Cold and Arid Regions environmental and Engineering Chinese Academy of Sciences Lanzhou China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by Wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2. All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3) The warming from 1975 to 2.00 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 2.th century.

Simulation　of　sludge－dredging　effects　in　controlling　nutrient　release　of　LakeKasumigaura　with　large－size　core　samples

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Journal of environmental Sciences 1996年第4期8卷 385-389页

作者： Fan Chengxin (Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences,Nanjing 2.0008,China) Morihiro AIZAKI Kunio KOHATA(The national Institute for environmental {2., tsukuba), japan Nanjing Inst. Geogr. and Limnology Chinese Academy of Sciences Nanjing 210008 China Natl. Inst. for Environ. studies Tsukuba Japan

Nutrient release from the dredged and undredged sediments in Lake Kasumigaura were simulated under the laboratory control conditions with large-size core samples. It was found that phosphate and ammonia release fluxes are less in aerobic than those in anaerobic. In different simulated dredged depth, the phosphate release showed large divergence in the anaerobic than in the aerobic. There was a larger accumulated release of phosphate and ammonia at actual dredged (St. B) than the undredged (St. A) in anaerobic condition. This showed that the sludge-dredging was effective of controlling phosphorus and nitrogen release. A preliminary assessment is drawn from the experiments that the sludge-dredging work in Tsuchiura Bay of Lake Kasumigaura can reduce about 15. 9% of phospbate and 56. 2. of anunonia release from the sediments respectively.

关键词： sludge-dredging nutrient release aerobic and anaerobic conditions core samples Lake Kasumigaura.

Relationship between petroleum hydrocarbon and plankton in a mesocosm experiment

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Acta Oceanologica Sinica 2001年第2期20卷 231-240页

作者： Shi Xiaoyong, Wang Xiulin, Han Xiurong, Jiang Yu Zhu Mingyuan, Chen Shang, Koshikawa Hiroshi (1. Ocean University of Qingdao, Qingdao 2.6003, China 2. First Institute of Oceanology, Qingdao 2.6061, China 3. national Institute for environmental {2., Ja Ocean University of Qingdao Qingdao 266003 China

A mesocosm experiment was carried out from May 2. to June 1, 1998 at the location of 30'52.N, 12.'36'E, the Changjiang Estuary, in order to measure the influence of petroleum hydrocar- bon to the ecosystem, furthermore, to estimate the environmental capacity. In the experiment, it is found that the petroleum hydrocarbon can, in some degree, enhance the growth of diatom, but inhibit the growth of dinoflagellate. In general, the petroleum hydrocarbon can inhibit the growth of both Phytoplankton and zooplankton, and can the inhibit the growth of total plankton (including phytoplankton and zooplankton) as well. A kinetic model was presented to estimate the uptake/release rate constants of petroleum hydrocarbon by plankton, and thereafter, the uptake and release rate constants (k1, k2., bioconcentration factor (BCF) as well as the petroleum bydrocarbon influenced influenced uptake and release rate constants of nutrients by phytoplankton (kup, krel) were obtained. The results imply that the bioconcentration of petroleum hydrocarbon by plankton is fairly large and petroleum hydrocarbon caused no significant influence on the uptake of N- NO3, but significant influence on that of P -PO4. In addition, the application of kinetic model for the bioconcentration of volatile organic toxic compound by organism suggests that the uptake of petroleum hydrocarbon by plankton was an important process for the environmental capacity of petroleum hydrocarbon.

关键词： Masochism petroleum hydrocarbon plankton nutrients kinetic model

environmental records of lacustrine sediments in different time scales:Sediment grain size as an example

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Science China Earth Sciences 2004年第10期47卷 954-960页

作者： CHEN Jing’an1, WAN Guojiang1, David Dian Zhang2. ZHANG Feng1 & HUANG Ronggui1 1. State Key Laboratory of environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. China 2. Department of Geography and Geology, University of Hong Kong, Pokfulam Road, Hong Kong, China 1. State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. Department of Geography and Geology University of Hong Kong Pokfulam Road Hong Kong China

Sediment grain size is a conventional proxy of climatic changes. Larger sediment grain size is often interpreted to indicate dry climate during lower lake level while smaller sedi- ment grain size implies wet climate during higher lake level. Through detailed study on sediment grain sizes in Lake Erhai and Lake Chenghai, this paper reveals the different indication signifi- cances of sediment grain sizes in different time scales, different resolution investigations. For long time-scale and low resolution (102. or 103a) studies, larger sediment grain size indicates lower lake level, smaller lake area and drier climate while smaller sediment grain size indicates higher lake level, larger lake area and wetter climate. For short time-scale and high resolution (a or 10a) studies, larger sediment grain size reflects more rainfall and wetter climate while smaller sediment grain size reflects less rainfall and drier climate. {2. information revealed by lacustrine sediment records is often different in different time scales because of the variance of sedimentation resolution, sampling resolution and dating precision. Therefore, paleoclimate im- plications of {2. proxies in long time-scale and low resolution investigations could not be mechanically applied to short time-scale and high resolution studies. Only after synthetically analyzing the influence manner and extent of all factors on the sediment records in different time scales, can credible conclusions be obtained.

关键词： lacustrine sediment, environmental record, grain size, time scale.

Multifield coupling model and its applications for pile foundation in permafrost

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Science China Earth Sciences 2005年第7期48卷 968-977页

作者： WU Yaping1,2. ZHU Yuanlin2. GUO Chunxiang1, SU Qiang1 & MA Wei2.1. School of Civil Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China 2. State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China School of Civil Engineering Lanzhou Jiaotong University Lanzhou 730070 China State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Importing the interface element which links the frozen soil base with concrete piles and considering the couplings of stress field, temperature field and moisture field, this paper es- tablishes the nonlinear visco-elastic plastic finite element model of pile-soil. For a practical bridge structure the stress field and displacement field of single pile in freezing process are calculated. This paper emphatically studies the process of the tangential frost heave stress field, freezing stress field and displacement field varying with time, and ulteriorly studies time variation process of single pile carrying capacity in freezing process.

关键词： permafrost pile foundation freezing process multifield coupling analysis model.

LEADAT: a MATLAB-based program for lead-2.0 data analysis of sediment cores

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Acta Oceanologica Sinica 2006年第6期25卷 128-136页

作者： LU Xueqiang MATSUMOTO Eiji Graduate School of environmental studies Nagoya University Nagoya 464 -8601 Japan environmental Science （SGES） Tamaki Campus University of Auckland Private Bag 92019 Auckland New Zealand

The program described herein （LEADAT） serves to calculate sediment date and sedimentation rate using the ^2.0pb method for the studies of environmental processes and pollution history on a time scale of 100 - 150 a. The program written in MATLAB （ Version7.0） permits the user to select the principal models of ^2.0pb method, i. e. , the constant fluxes of sediment and lead-2.0 （ CF- SL） model, the constant flux of lead-2.0 （CFL） model, the constant initial concentration of lead-2.0 （CICL） model and the twolayer mixing （TLM） model. Although appropriate model selection is essentially based on understanding of the sedimentary processes, the pattern of the excess ^2.0pb profile is also helpful for model selection. The excess ^2.0pb profiles for two sediment cores collected from a brackish lake and an embayment respectively are used to demonstrate the application of the program. With a graphical user interface, the program can be easily executed. Not only ASCII but also graphical output can be generated by means of the program. Meanwhile, the code can be modified easily for extension.

关键词： Lead-2.0 method sediment dating sedimentation rate environmental change

Contribution of Root and Microbial Respiration to Soil CO_2.Efflux and Their environmental Controls in a Humid Temperate Grassland of japan

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of Urban and environmental Sciences Northeast Normal University Changchun 130024 （China） Institute of Biological Sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2.efflux, root mass, and root production were investigated in a humid temperate grassland of japan over a growing season （Apr. to Sep.） of 2.05 to reveal seasonal changes of soil CO2.efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2.efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2.effiux and root mass at different experimental sites. Soil CO2.efflux, ranging from 4.99 to 16.2. μmol CO2.m^-2.s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82.and 1.2. kg m^-2.in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-30 cm depth varied from 8 to 180 g m^-2.month^-1. Microbial and root respiration rates ranged from 1.35 to 5.51 and 2.72.to 12.06μmol CO2.m^-2.s^-1, respectively. The contribution of root respiration to the total soil CO2.efflux averaged 53%, ranging from 33% to 72.. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2.= 0.9400, P = 0.002. n = 6）, and the root respiration rate was linearly related to the root production at 0-30 cm depth （R2.= 0.6561, P = 0.042. n = 6）.

关键词： grasslands microbial respiration root production root respiration

N Cycle, N Flow Trends in japan, and Strategies for Reducing N_2. Emission and NO_3^- Pollution

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Pedosphere 2005年第2期15卷 164-172页

作者： K.MINAMI national Institute for Agro-environmental Sciences

To feed an increasing population, large amounts of chemical nitrogen fertilizer have been used to produce much of our food, feed and fiber thereby increasing nitrogen levels in soils, natural waters, crop residues, livestock wastes,and municipal and agricultural wastes, with national and international concern about its potential adverse effects on {2. quality and public health. To understand these phenomena and problems, first the nitrogen cycle and the environment are described. Then recent trends for nitrogen cycling through the food and feed system, N2. emissions from fertilized upland and paddy soils, and NO-3 pollution in ground water in japan are reported. Finally, mitigation strategies in japan for reducing N2. emission and NO-3 pollution are proposed, including nitrification inhibitors, controlled release fertilizers, utilization of plant species that could suppress nitrification, utilizing the toposequence, government policy, and appropriate agricultural practices. Of all the technologies presented, use of nitrification inhibitors and controlled release fertilizers are deemed the most important with further development of these aspects of technologies being expected. These practices, if employed worldwide, could help reduce the load, or {2. deterioration, on the Earth's biosphere.

关键词： mitigation strategy N2. emission NO3- pollution nitrogen cycle