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Numerical modelling of Lagrangian residual current in the Bohai Strait

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Acta Oceanologica Sinica 1988年第2期 186-194页

作者： Li Longzhang, Dou Zhenxing and Zhang Cunzhi Institute of Marine environmental protection, state Oceanic administration, Dalian, china

The Bohai Strait is the only passage-way of the semienclosed Bohai Sea into the outer ocean. The various dynamical processes have great effects on both sides of the strait, especially on the Bohai Sea. Tidal current dominates in the strait, and among the tida! components the M, component tide is *** seawater in the strait is homogeneous vertically almost the whole year because of strong tidal mixing. The M, component tide was simulated numerically using two dimensional barotropical model, and the Eulerian tide-induced residual currents were also deduced. The results showed that the tidal currents were dominated by the coastal line and topography. There exist many eddies in the tide-induced residual current fields, particularly near the northern *** the basis of the simulation of the tidal currents, the movements of the water particles in the strait were tracked by means of Lagrangian techniques. Consequently the Lagrangian residual currents were obtained. Somewhat similar to the Eulerian

关键词： Bohai tidal Lagrangian currents vertically Eulerian dominated ocean tracked mixing

Responses of soil respiration in non-growing seasons to environmental factors in a maize agroecosystem,Northeast china

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Chinese Science Bulletin 2010年第24期55卷 2723-2730页

作者： LI RongPing1,2,3, ZHOU GuangSheng1,4 & WANG Yu1,3 1 state Key Laboratory of Vegetation and environmental Change, Institute of Botany, Chinese Academy of Sciences, beijing 100093, china 2 Institute of Atmospheric Environment, china Meteorological administration, Shenyang 110016. china 3 Graduate University of Chinese Academy of Sciences, beijing 100049, china 4 Chinese Academy of Meteorological Sciences, beijing 100081, china state Key Laboratory of Vegetation and environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China Institute of Atmospheric Environment China Meteorological Administration Shenyang 110016 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Chinese Academy of Meteorological Sciences Beijing 100081 China

Based on continuous three-year measurements (from 2004 to 2007) of eddy covariance and related environmental factors, environmental controls on variation in soil respiration (Rs) during non-growing season were explored in a maize agroecosystem in Northeast china. Our results indicated that during non-growing seasons, daily Rs was 1.08-4.08 g CO2 m-2 d-1, and the lowest occurred in late November. The average Rs of non-growing season was 456.06.± 20.01 g CO2 m-2, accounting for 11% of the gross primary production (GPP) of the growing season. Additionally, at monthly scale, the lowest value of Rs appeared in January or February. From the beginning to the end of non-growing season, daily Rs tended to decrease first, and then increase to the highest. There was a significant quadratic curve relationship between Rs and soil temperature at 10 cm depth when soil temperature was more than 0°C (P6.%. Based on all the data of soil temperature of more than 0°C, a better model for Rs was established by coupling soil temperature and moisture, which could explain the rate of up to 53%-79%. Meanwhile, the standard error of regression estimation between the values of prediction and observation for Rs could reach 2.7%-11.8%. Rs in non-growing season can account for 22.4% of Rs in growing season, indicating that it plays a critical role in assessing the carbon budget in maize agroecosystem, Northeast china.

关键词：中国东北地区农田生态系统生长季节土壤呼吸环境因素玉米土壤含水量反应

Solar release time of solar energetic particles and associated acceleration source in corona

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Chinese Science Bulletin 2008年第2期53卷 161-168页

作者： LE GuiMing1,2,3,4, TANG YuHua1 & HAN YanBen4 1 Department of Astronomy, Nanjing University, Nanjing 210093, china 2 Key Laboratory of Radiometric Calibration and Validation for environmental Satellites, china Meteorological administration, beijing 100081, china 3 National Center for Space Weather, china Meteorological administration, beijing 100081, china 4 National Astronomical Observatories, Chinese Academy of Sciences, beijing 100012, china Department of Astronomy Narijing University Nanjing 210093 China Key Laboratory of Radiometric Calibration and Validation for environmental Satellites China Meteorological Administration Beijing 100081 China National Center for Space Weather China Meteorological Administration Beijing 100081 China Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Solar energetic particles (SEPs) are accelerated in corona at an early phase of solar energetic particle events (SEPE). The acceleration mechanism of SEPs in corona can only be inferred from an analysis of multi-band observational data, as the observation of SEPs is usually made around 1AU. In this context, people have investigated spectrums, charge state, solar release time (SRT), and multi-band data of SEPEs, in an attempt to judge the acceleration mechanism of SEPs. The SRT computation of SEPs is an important and commonly used approach to study the acceleration mechanism of SEPs in corona. This paper reviews some important findings concerning the SRT computation of SEPs, and analyzes different merits of each approach for such calculation, based on a range of SEPE case studies. This paper also analyzes and discusses both possible and actual acceleration mechanisms of a number of SEPEs, by calculating the SRT of the SEPEs. Finally, the paper summarizes the possible problems in studying an acceleration mechanism of SEPEs inferred from the SRT of SEP.

关键词：阳光释放时间加速度电晕太阳耀斑

Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea

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Chinese Science Bulletin 2003年第B6期48卷 37-41页

作者： GE Shulan~(1,2,3), SHI Xuefa~1 & HAN Yibing~1 1. Key Laboratory of Marine Sedimentology and environmental Geology, First Institute of Oceanography, state Oceanic administration. Qingdao 26.06.. china 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029. china 3. Graduate School. Chinese Academy of Sciences, {6. 100039. china Key Laboratory of Marine Sedimentology and environmental Geology First Institute of Oceanography State Oceanic Administration Qingdao China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 172 surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assemblages in the continental sea, which indicates different sediment origins. With the 30 μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe *** L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East china Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are *** the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface soil as a climate proxy.

关键词：中国黄海表面沉积物磁化率等值线长江黄河旋涡沉积区循环系统

The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2,4, ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3 1. state Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china 2. Department of Atmospheric Sciences, Yunnan University, Kunming 6.0091, china 3. china Meteorological administration Training Centre, {6. 100081, china 4. Graduate School of Chinese Academy of Sciences, {6. 100039, china state Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric Sciences Yunnan University Kunming 650091 China Graduate School of Chinese Academy of Sciences Beijing 100039 China china Meteorological administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South china Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2nd pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

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中国环境法制建设的进展与任务

上海环境科学 2003年第1期22卷 1-5页

作者：王玉庆国家环境保护总局北京100035

总结了中国在环境法制建设所取得的成就,指出经过20多年的努力,中国已基本形成了适应社会主义市场经济体制、具有中国特色的环境法律体系。分析了当前环境法制建设中存在的突出问题及其原因。提出了“十五”期间全国环境法制建设的主要... 详细信息

总结了中国在环境法制建设所取得的成就,指出经过20多年的努力,中国已基本形成了适应社会主义市场经济体制、具有中国特色的环境法律体系。分析了当前环境法制建设中存在的突出问题及其原因。提出了“十五”期间全国环境法制建设的主要任务及措施。强调要通过加强前期调研,不断提高立法质量;强化环境行政执法,依法严厉查处各类环境违法行为,严厉打击环境犯罪;并通过建立有奖举报制度,完善公众参与环境执法的监督机制。

关键词：中国环境法制建设环境法学环境违法行为环境犯罪公众参与环境法律体系

Water demand for ecosystem protection in rivers with hyper-concentrated sediment-laden flow

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Science china(Technological Sciences) 2004年第z1期47卷 186-198页

作者： LUO Huaming, LI Tianhong, NI Jinren & WANG Yudong Department of environmental Engineering, Peking University, beijing 100871, china The Key Laboratory of Water and Sediment Sciences, Ministry of Education, beijing 100871, china Department of environmental Engineering Peking University Beijing 100871 China

Sediment transport is one of the main concerns in a river system with hyper-concentrated flows. Therefore, the water use for sediment transport must be considered in study on the water demand for river ecosystem. The conventional methods for calculating the Minimum Water Demand for River Ecosystem (MWDRE) are not appropriate for rivers with high sediment concentration. This paper studied the MWDRE in wet season, dry season and the whole year under different water-and-sediment conditions in the Lower Yellow River, which is regarded as a typical river with sediment-laden flows. The characteristics of MWDRE in the river are analyzed. Firstly, the water demand for sediment transport (WDST) is much larger than the demands for other riverine functions, the WDST accounts for the absolute majority of the MWDRE. Secondly, in wet season when the WDST is satisfied, not only most of the annual incoming sediment can be transported downstream, but also the water demands for other river functions can be satisfied automatically, so that the MWDRE in wet season is identical to the WDST. Thirdly, in dry season, when the WDST is satisfied, the water demands for other river functions can also be satisfied, but the low sediment transport efficiency results in significant waste of water resources. According to these characteristics and aiming at decreasing sediment deposition in the riverbed and improving the utilization efficiency of water resources, hydrological engineering works can be used to regulate or control flow and sediment so that the sediment incoming in dry season can be accumulated and be transported downstream intensively and thus efficiently in wet season.

关键词： sediment-laden flow, the Lower Yellow River, water demand for river ecosystem, water demand for sediment transport

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我国湖泊的限磷、禁磷现状及对策

上海环境科学 1999年第9期18卷 388-389,396页

作者：胡明国家环境保护总局北京100035

介绍了含磷洗涤剂对湖泊富营养化的影响;国内外限磷、禁磷研究的发展趋势以及我国水污染治理中对含磷洗涤剂应采取的具体对策。并结合我国国情,提出了应地制宜地制定限磷、禁磷政策的建议。

关键词：限磷禁磷湖泊富营养化现状对策中国

A Consideration of Nuclear Emeryency Planning and Preparedness on Qinshan Nuclear Power Base

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A Consideration of Nuclear Emeryency Planning and Preparedne...