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Journal of Hydrodynamics 2008年第3期20卷 373-381页

作者： CHEN Bin wang Kai Institute of oceanology Chinese Academy of Sciences Qingdao 266071 China graduate university of the chinese academy of sciences Beijing 100039 China

Based on the Estuarine, Coastal and ocean Modeling System with Sediments （ECoMSED） model, a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East China Sea .The hydrodynamic module was driven by tide and wind. Sediment module included sediment resuspension, transport and deposition of cohesive and non-cohesive sediment. The settling of cohesive sediment in the water column was modeled as a fimction of aggregation （flocculation） and deposition. The numerical results were compared with observation data for August, 2006. It shows that the sediment concentration reduces gradually from the seashore to the offshore area. Numerical results of concentration time series in the observation stations show two peaks and two valleys, according with the observation data. It is mainly affected by tidal current. The suspended sediment concentration is related to the tidal current during a tidal cycle, and the maximum concentration appears 1 h-4 h after the current maximum velocity has reached.

关键词： Yangtze Estuary sediment concentration sediment transport

Evidence from isotopic geochemistry as an indicator of eutrophication of Meiliang Bay in Lake Taihu, China

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Science China Earth sciences 2006年第Z1期49卷 62-71页

作者： LIN Lin, WU Jinglu & wang Sumin Nanjing Institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008, China graduate university of the chinese academy of sciences, Beijing 100039, China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing China graduate university of the chinese academy of sciences Beijing China

In this paper, Lake Taihu, a large shallow freshwater lake in China, is chosen as an example of reconstruction of eutrophication through the comparison between stable isotopes from dissolved nutrients and plants and water column nutrient parameters and integration of multiple p.o.ies in a sediment core from Meiliang Bay including TN, Tp, ToC, C/N, δ15N, δ13C, etc. Differences in aquatic plant species and trophic status between East Taihu Bay and Meiliang Bay are indicated by their variations in δ13C and δ15N of aquatic plants and δ15N of NH4+. A significant influence ofexternal nutrient inputs on Meiliang Bay is reflected in temporal changes in δ 15N of NH4+ and hydro-environmental parameters. The synchronous change between δ13C and δ15N values of sedimented organic matter (oM) has been attributed to elevated primary p.o.uction at the beginning of eutrophication between 1950 and 1990, then recent inverse correlation between them has been caused by the uptake of 15N-enriched inorganic nitrogen by phytoplankton grown under eutrophication and subsequent oM decomposition and denitrification in surface sediments, indicating that the lake has suffered from p.o.ressive eutrophication since 1990. Based on the use of a combination of stable isotopes and elemental geochemistry, the eutrophication of Meiliang Bay in Lake Taihu could be better traced. These transitions of the lake eutrophication respectively occurring in the 1950s and 1990s have been suggested as a reflection of growing impacts of human activities, which is coincident with the instrumental data.

关键词： stable carbon isotope of oM, stable nitrogen isotope, eutrophication, Lake Taihu.

Genetic structure and phylogeography of a relict tree fern,Sphaeropteris brunoniana (Cyatheaceae) from China and Laos inferred from cpDNA sequence variations:Implications for conservation

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Journal of Systematics and Evolution 2011年第1期49卷 72-79页

作者： 1,2 Zi-Juan wang 1 Kai-Yun GUAN 1 (Kunming Institute of Botany, chinese academy of sciences, Kunming 650204, China) 2 (graduate university of chinese academy of sciences, Beijing 100049, China) (Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate university of chinese academy of sciences Beijing 100049 China)

In this study, we analyzed the genetic structure and phylogeography of Sphaeropteris brunoniana from China and Laos. Combining cpDNA trnL-trnF and atpB-rbcL sequence variations, five hap.o.ypes were identi- fied from the 10 investigated populations. Moderate hap.o.ype diversity (h = 0.66580) and low nucleotide diver- sity (π = 0.23 × 10 ?3 ) were detected. The S. brunoniana in Yunnan region had much higher genetic diversity (h = 0.60195, π = 0.35 × 10 ?3 ) than that of Hainan–Laos (h = 0.00000, π = 0.00). A high level of genetic differentiation (94.74%) between the two regions was revealed by AMoVA. Nested clade analysis identified two major clusters of the five hap.o.ypes, one clade in the Yunnan region and the other in Hainan–Laos. The analysis indicated that restricted gene flow with isolation by distance and allopatric fragmentation were likely the major p.o.esses that shaped the spatial distribution of the hap.o.ypes. The isolated distribution of clades implied the emergence of independent refugia of this species in each region during Quaternary glaciations. The Yunnan populations frequently contained an ancestral hap.o.ype, and most of them harbored other descendent hap.o.ypes. Based on the distribution pattern of hap.o.ypes and the nested clade analysis results, the Yunnan region potentially had several refugia of this species during glacial periods, whereas the Hainan populations were p.o.able new colonizations.

关键词： atpB-rbcL Hainan–Laos phylogeography Sphaeropteris brunoniana trnL-trnF Yunnan.

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 Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing 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

Effects of various solar indices on accuracy of Earth’s thermospheric neutral density models

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Science China(physics,Mechanics & Astronomy) 2009年第7期52卷 1120-1128页

作者： wang HongBo1,2 & ZHAo ChangYin1 1 purple Mountain observatory, chinese academy of sciences, Nanjing 210008, China 2 graduate university of chinese academy of sciences, Beijing 100049, China purple Mountain observatory Chinese Academy of Sciences Nanjing China graduate university of chinese academy of sciences Beijing China

Four kinds of solar indices F10.7, E10.7, S10, Mg10 and four thermospheric neutral density models, i.e., CIRA72, DTM94, NRLMSISE00 and JB2006, are discussed. The CHAMp accelerometer data are used to calculate thermospheric total mass density. Based on the comparison of the model densities with CHAMp.o.servations, the effects of various indices on the model accuracy are detected. It is found that under quiet and moderate solar conditions (F10.7of the models’ errors are reduced about 15% by using E10.7 instead of F10.7, while under active solar conditions (F10.7>200) the error’s standard deviation using E10.7 increases quickly and causes the models’ accuracy to fall down. With regard to S10, Mg10, their effects under quiet solar conditions are inconspicuous. If under active solar conditions, they can reduce the model error’s standard deviation by 5%-10%, implying that S10, Mg10 make the model error more stable. The JB2006 model, which was constructed by multi-solar-index (F10.7, S10, Mg10), is compared with DTM94 and NRLMSISE00 based on single-solar-index. It is found that JB2006’s accuracy is better than DTM94’s, and is close to NRLMSISE00 under the quiet solar condition. During the solar burst occurring on october 26, 2003, JB2006 has been in best agreement with CHAMp.o.servations. All in all, the new indices may imp.o.e thermospheric density models’ accuracy under some special conditions. Concretely, E10.7 may reduce the average error of models and S10, Mg10 may prevent the error’s divergence.

关键词： solar radiation index CHAMp accelerometer data neutrals density model

Modeling diameter distribution of the broadleaved-Korean pine mixed forest on Changbai Mountains of China

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Science China(Technological sciences) 2006年第Z1期49卷 177-188页

作者： wang Shunzhong, DAI Limin, LIU Guohua, YUAN Jianqiong, ZHANG Hengmin & wang Qingli Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, China graduate university of chinese academy of sciences, Beijing 100039, China State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085, China Institute of Applied Ecology Chinese Academy of Sciences Shenyang China graduate university of chinese academy of sciences Beijing China State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China

The broadleaved-Korean pine mixed forest is a native vegetation in the Changbai Mountains, northeast China. The p.o.ability density functions including the normal, negative exponential, Weibull and finite mixture distribution, were used to describe the diameter distributions of the species groups and entire forest stand. There is a strong correlation between parameters and mean DBH except the shape parameters in the mixture distribution. The diameter classes of species and entire forest stand showed not negative exponential but normal and "S" distribution. The mixture function was better than normal and Weibull to describe the model distribution. The location parameter had an effect on the estimated frequency in the first diameter class, when the estimated location parameter was bigger than the lower limit of the first diameter class.

关键词： broadleaved-Korean pine mixed forest, diameter distribution, finite mixture distribution.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science China(Technological sciences) 2010年第9期53卷 2521-2527页

作者： wang Ke1,2,REN WeiJia1,wang ShiDa1 & WENG LiJun3 1 academy of op.o.Electronics,chinese academy of sciences,Beijing 100190,China 2 graduate university of chinese academy of sciences,Beijing 100049,China 3 Lanzhou Institute of Chemical physics,chinese academy of sciences,Lanzhou 730000,China academy of op.o.Electronics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China Lanzhou Institute of Chemical physics Chinese Academy of Sciences Lanzhou China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of China,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

The deep thermal characteristic of continental margin of the northern South China Sea

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chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & wang Jiyang1. graduate School, university of Science and Technology of China, chinese academy of sciences, Beijing 100039, China 2. Institute of Geology, chinese academy of sciences, Beijing 100029, China graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South China Sea. The analysis of heat flow value shows that margin heat flow in the northern South China Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the p.o.ortion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up.o. hot material from asthenosphere.

关键词： margin of northern South China Sea terrestrial heat flow thermal structures.

Impact of the Wenchuan Earthquake on Tourism in Sichuan,China

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Journal of Mountain Science 2008年第3期5卷 194-208页

作者： YANG Weiqiong CHEN Guojie wang Daojie Institute of Mountain Hazard and Environment Chinese Academy of Sciences Chengdu 610041 China graduate university of chinese academy of sciences Beijing 100049 China

An intensive earthquake, the Wenchuan Earthquake of 8.0 on the Richter scale, struck western Sichuan, China on May 12, 2008. The earthquake has tremendously affected all industries in the quake-hit areas, with no exception of the local tourism. The study of the effect of the earthquake on tourism enriches the theory of tourism, and more importantly, it well serves as the foundation for policy making. The objective of this study is to outline for readers the empirical findings on the various ways that the earthquake affected the operations and viability of tourism in the quake-hit areas. This paper is mainly divided into 3 parts. The first part is to discuss the importance of tourism in the quake-hit areas. The second is to analyze the influencing factors of tourism. The third is to assess the impact of the earthquake on tourism in Sichuan in different seasons.

关键词： Wenchuan Earthquake Tourism Impact factors of Tourism Economic Loss