Science.gov

Sample records for adjacent east china

  1. Metal elements in the bottom sediments of the Changjiang Estuary and its adjacent continental shelf of the East China Sea.

    PubMed

    Cao, Lu; Hong, Gi Hoon; Liu, Sumei

    2015-06-15

    The metal elements (Al, Fe, Mn, Cr, Co, Ni, Cu, Zn, As, Pb and Ca) in the bottom sediment of the Changjiang Estuary and its adjacent continental shelf of the East China Sea were studied to map their spatial distribution and to assess their potential risk to the marine biota. These metal concentrations except Ca were generally higher in the inner shelf and northeastern part, and were found to decrease from the coast to the offshore of the Changjiang Estuary. Sedimentary Ca was most abundant in the outer shelf sediments and decreased in inner shelf. Arsenic (As) appeared to be contaminated due to economic development from 1980s in the inner shelf overall, but the potential ecological risk from the selected metals was low in the coastal sea off the Changjiang.

  2. On the tectonic problems of the southern East China Sea and adjacent regions: Evidence from gravity and magnetic data

    NASA Astrophysics Data System (ADS)

    Shang, Luning; Zhang, Xunhua; Han, Bo; Du, Runlin

    2016-02-01

    In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system: one data set was from the `Geological-geophysical map series of China Seas and adjacent areas' database and the other was newly collected by R/V Kexue III in 2011. Magnetic and gravity data were reorganized and processed using the software MMDP, MGDP and RGIS. In addition to the description of the anomaly patterns in different areas, deep and shallow structure studies were performed by using several kinds of calculation, including a spectrum analysis, upward-continuation of the Bouguer anomaly and horizontal derivatives of the total-field magnetic anomaly. The depth of the Moho and magnetic basement were calculated. Based on the above work, several controversial tectonic problems were discussed. Compared to the shelf area and Ryukyu Arc, the Okinawa Trough has an obviously thinned crust, with the thinnest area having thickness less than 14 km in the southern part. The Taiwan-Sinzi belt, which terminates to the south by the NW-SE trending Miyako fault belt, contains the relic volcanic arc formed by the splitting of the paleo Ryukyu volcanic arc as a result of the opening of the Okinawa Trough. As an important tectonic boundary, the strike-slip type Miyako fault belt extends northwestward into the shelf area and consists of several discontinuous segments. A forearc terrace composed of an exotic terrane collided with the Ryukyu Arc following the subduction of the Philippine Sea Plate. Mesozoic strata of varying thicknesses exist beneath the Cenozoic strata in the shelf basin and significantly influence the magnetic pattern of this area. The gravity and magnetic data support the existence of a Great East China Sea, which suggests that the entire southern East China Sea shelf area was a basin in the Mesozoic without alternatively arranged uplifts and depressions, and might have extended southwestward and connected with the

  3. Particulate nitrogen and phosphorus in the East China Sea and its adjacent Kuroshio waters and evaluation of budgets for the East China Sea Shelf

    NASA Astrophysics Data System (ADS)

    Zuo, Jiulong; Song, Jinming; Yuan, Huamao; Li, Xuegang; Li, Ning; Duan, Liqin

    2016-12-01

    Nitrogen (N) and phosphorus (P) in suspended particles are important to the cycles of N and P in marine ecosystem. Suspended particles were collected from the East China Sea (ECS) and its adjacent Kuroshio waters to investigate the composing and distribution characteristics of particulate inorganic and organic nitrogen and phosphorus (PIN, PIP, PON and POP, respectively). The particulate N and P concentrations were fairly low in the Kuroshio water but much higher in the ECS water, especially in nearshore waters. PON and PIP were the dominant forms of particulate N and P, with an exception that POP was the major form of particulate P in the Kuroshio upper water. The regime of particulate N and P in the ECS was strongly influenced by riverine input, oceanic input, ocean current and photosynthesis. Among them, PON and POP were mainly from biogenic source, while PIN and PIP were originated from biogenic and external sources. And sedimentation, remineralization and resuspension were important influencing factors for the vertical distributions of particulate N and P. The budgets of particulate N and P for the ECS Shelf during rainy season (May-October) were also evaluated. The total particulate N and P (TPN and TPP) fluxes from oceanic input are respectively 10.99 and 2.49 times of those from riverine input. And oceanic input contains more POP, which is liable to be decomposed into phosphate, than riverine input. Furthermore, particulate nutrients fluxes from photosynthesis are the overriding source of total influxes for the ECS Shelf, accounting for 90.93% of TPN and 89.37% of TPP influxes. As for the photosynthetic fixed N and P, only 6.17% and 7.60% of them can reach the seafloor, while up to 87.73% and 60.06% of them are likely to be remineralized. The POP-rich oceanic input and the intensive photosynthesis and remineralization processes play important roles in the biogeochemical cycles of N and P in the ECS.

  4. Controlling factors of summer phytoplankton community in the Changjiang (Yangtze River) Estuary and adjacent East China Sea shelf

    NASA Astrophysics Data System (ADS)

    Jiang, Zhibing; Chen, Jianfang; Zhou, Feng; Shou, Lu; Chen, Quanzhen; Tao, Bangyi; Yan, Xiaojun; Wang, Kui

    2015-06-01

    We analyzed the composition and distribution of phytoplankton in relation to physicochemical factors in the Changjiang (Yangtze River) Estuary and adjacent East China Sea shelf in June and August 2009. Diatoms and dinoflagellates dominated the community, particularly in eutrophic inshore waters controlled by the Changjiang Diluted Water (CDW), coastal current, and upwelling. However, high densities of cyanobacteria and cryptophytes were observed in the oligotrophic offshore waters influenced by the Taiwan Warm Current (TWC) and Kuroshio. In June, the northeastward CDW plume combined with the Yellow Sea Coastal Current induced algal bloom in the northern part of the CE. In August, the enhanced CDW formed two narrow, low-salinity tongues that extended eastward and southward (associated with the upwelling and coastal current), resulting in phytoplankton blooms off the CE and in the Zhejiang coastal waters, respectively. Phytoplankton abundance in August was considerably higher than in June, with increased solar radiation, CDW, and upwelling. The maximum abundance occurred on the surface in inshore turbid waters and on the subsurface (5-30 m) in offshore clear waters with increased stratification. Based on multidimensional scaling and cluster analysis, we found appreciable spatio-temporal variations in algal community composition. Different ecological groups corresponded with hydrographic distributions. Canonical correspondence analysis showed that nutrients, salinity, temperature, and suspended particulate matter were the main variables associated with community distribution. We suggest that the variations in summer phytoplankton community are highly correlated with the significant monthly and spatial variability in physicochemical properties, which are primarily controlled by the CDW and TWC.

  5. Community composition and distribution of sulfate- and sulfite-reducing prokaryotes in sediments from the Changjiang estuary and adjacent East China Sea

    NASA Astrophysics Data System (ADS)

    He, Hui; Zhen, Yu; Mi, Tiezhu; Xu, Bochao; Wang, Guoshan; Zhang, Yu; Yu, Zhigang

    2015-11-01

    Sulfate- and sulfite-reducing prokaryotes (SSRP) communities play a vital role in both sulfur and carbon cycles. Community composition and abundance of SSRP were investigated using dissimilatory sulfite reductase β subunit (dsrB) gene sequencing in sediments from the Changjiang estuary and its adjacent area in the East China Sea (ECS). Clone libraries were constructed and real-time fluorescence quantitative polymerase chain reaction (qPCR) was applied to understand the community information of SSRP. In addition to sequences affiliated to sulfate-reducing prokaryotes (SRP), those affiliated with sulfite-reducing prokaryotes (SiRP) were also observed. Four phylotypes of SRP in this study showed genetic similarity to Desulfobulbaceae, Syntrophobacteraceae, Desulfobacteraceae and Peptococcaceae, and an unknown group that could not be clearly affiliated with known lineages was found. Salinity, temperature and contents of total organic carbon (TOC) were most closely correlated with the SSRP communities by canonical correspondence analysis (CCA). 210Pb activities demonstrated the sedimentary environment at S33 was more stable than that at S31. Intense resuspension and reconstruction of sediments made the vertical abundance profile of SSRP fluctuate violently. For surface sediments, the dsrB gene copy numbers near the Changjiang estuary were higher than those in the mouth of Hangzhou Bay and the mud deposits along the Zhejiang coast, and contents of TOC were positively related to the copy numbers of dsrB gene. Our data provided valuable information to achieve a better understanding of the potential role of SSRP in sediments from the Changjiang estuary and adjacent East China Sea.

  6. Responses of seawater temperature and chlorophyll-a to typhoons passing through the Changjiang Estuary and the adjacent East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, G.; Gao, L.; Li, D.

    2013-12-01

    Sea surface temperature (SST) data obtained from the Physical Oceanography Distributed Active Archive Center (PODAAC) and chlorophyll-a (Chl-a) concentrations extracted from the Moderate Resolution Imaging Spectroradiometer (MODIS) on Aqua were used to study the passed typhoons' influence on the Changjiang Estuary and the adjacent East China Sea (28-33° N, 122-126° E), during the past ten years from 2002 to 2012. All together data before and after four typhoons, i.e., typhoons named Rananim in 2004, Shanshan in 2006, Jangmi in 2008 and Kompasu in 2010, were successfully retrieved due to the good weather conditions. After the four typhoons, the overall Chl-a concentrations in the study area were greatly increased by 62% (averaged by the four typhoon events) within the circles of storm wind (> 88 km/h) and by 38% within the circles of gale wind (> 62 km/h), however, no obvious change was detected in regions outside the gale wind circles. On the other hand, significant SST decrease was observed during the same periods but in a larger area. SST declined by an average level of 4.5% within the storm wind circle and approximately 3% both inside and outside the gale wind circle. Although these typhoons could potentially decrease the SST in the Changjiang Estuary and the adjacent East China Sea, however, these decrease ranges were still smaller compared to those SST variations caused by the natural climate change. In addition, typhoons with different paths and different intensities influenced the Chl-a concentrations in different ways. From 2002 to 2012, 18 typhoons had passed the study area, among which 13 typhoons moved in a northward or northwestward direction, and 16 had ranked to be the storm wind. Among the typhoons that showed similar intensities, those that moved northwards or northwestwards seemed to have played the stronger effects on the study area. The different physical and chemical conditions (including nutrient-limitation status, terrestrial discharge from

  7. Lock 4 View east of lock wall and adjacent ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Lock 4 - View east of lock wall and adjacent roadway built atop tow path. The gate pocket can be seen at center. - Savannah & Ogeechee Barge Canal, Between Ogeechee & Savannah Rivers, Savannah, Chatham County, GA

  8. 6. Detail, vertical guides adjacent to east portal of Tunnel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Detail, vertical guides adjacent to east portal of Tunnel 28, view to southwest, 135mm lens with electronic flash fill. - Central Pacific Transcontinental Railroad, Tunnel No. 28, Milepost 134.75, Applegate, Placer County, CA

  9. 73. PASSAGE ADJACENT TO ROOM 232, EAST WING, SECOND FLOOR, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    73. PASSAGE ADJACENT TO ROOM 232, EAST WING, SECOND FLOOR, LOOKING WEST BY NORTHWEST, SHOWING EASTERNMOST ARCH OF FORMER GREAT HALL NORTH ARCADE - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  10. Mercury Export from Mainland China to Adjacent Seas and Its Influence on the Marine Mercury Balance.

    PubMed

    Liu, Maodian; Chen, Long; Wang, Xuejun; Zhang, Wei; Tong, Yindong; Ou, Langbo; Xie, Han; Shen, Huizhong; Ye, Xuejie; Deng, Chunyan; Wang, Huanhuan

    2016-06-21

    Exports from mainland China are a significant source of mercury (Hg) in the adjacent seas (Bohai Sea, Yellow Sea, East China Sea, and South China Sea) near China. A total of 240 ± 23 Mg was contributed in 2012 (30% from natural sources and 70% from anthropogenic sources), including Hg from rivers, industrial wastewater, domestic sewage, groundwater, nonpoint sources, and coastal erosion. Among the various sources, the Hg from rivers amounts to 160 ± 21 Mg and plays a dominant role. The Hg that is exported from mainland China increased from 1984 to 2013; the contributions from rivers, industrial wastewater, domestic sewage and groundwater increased, and the contributions from nonpoint sources and coastal erosion remained stable. A box model is constructed to simulate the mass balance of Hg in these seas and quantify the sources, sinks and Hg biogeochemical cycle in the seas. In total, 160 Mg of Hg was transported to the Pacific Ocean and other oceans from these seas through oceanic currents in 2012, which could have negative impacts on the marine ecosystem. A prediction of the changes in Hg exportation through 2030 shows that the impacts of terrestrial export might worsen without effective pollution reduction measures and that the Hg load in these seas will increase, especially in the seawater of the Bohai Sea, Yellow Sea, and East China Sea and in the sea margin sediments of the Bohai Sea and East China Sea.

  11. Contrasting microbial assemblages in adjacent water masses associated with the East Australian Current.

    PubMed

    Seymour, Justin R; Doblin, Martina A; Jeffries, Thomas C; Brown, Mark V; Newton, Kelly; Ralph, Peter J; Baird, Mark; Mitchell, James G

    2012-10-01

    Different oceanographic provinces host discrete microbial assemblages that are adapted to local physicochemical conditions. We sequenced and compared the metagenomes of two microbial communities inhabiting adjacent water masses in the Tasman Sea, where the recent strengthening of the East Australian Current (EAC) has altered the ecology of coastal environments. Despite the comparable latitude of the samples, significant phylogenetic differences were apparent, including shifts in the relative frequency of matches to Cyanobacteria, Crenarchaeota and Euryarchaeota. Fine-scale variability in the structure of SAR11, Prochlorococcus and Synechococcus populations, with more matches to 'warm-water' ecotypes observed in the EAC, indicates the EAC may drive an intrusion of tropical microbes into temperate regions of the Tasman Sea. Furthermore, significant shifts in the relative importance of 17 metabolic categories indicate that the EAC prokaryotic community has different physiological properties than surrounding waters.

  12. Changes in Climate over the South China Sea and Adjacent Regions: Response to and Feedback on Global Climate Change

    NASA Astrophysics Data System (ADS)

    Yang, Song

    2016-04-01

    El Niño-Southern Oscillation and the Asian monsoon have experienced significant long-term changes in the past decades. These changes, together with other factors, have in turn led to large climate change signals over the South China Sea and adjacent regions including Southeast Asia, the western Pacific, and the tropical Indian Ocean. An attribution analysis of the feedback processes of these signals indicate the predominant importance of water vapor and cloud radiative feedbacks. Experiments with multiple earth system models also show that these regional climate change signals exert significant influences on global climate. The increases in atmospheric heating over Southeast Asia and sea surface temperature in the adjacent oceans in the past decades have weakened the Indian and African monsoons, led to a drying effect over East Asia, and generated wave-train patterns in both the northern and southern hemispheres, explaining several prominent climate features in and outside Southeast Asia.

  13. East China plains: a "basin" of ozone pollution.

    PubMed

    Zhao, Chun; Wang, Yuhang; Zeng, Tao

    2009-03-15

    Economic growth and associated pollution emissions in China are concentrated over three connected plains to the east In this work, we analyze an episode of highly elevated ozone over East China on June 9-14, 2004, using a 3-D chemical transport model. During this episode, the East China plains were under a high-pressure system, which suppressed the ventilation of pollutants from the boundary layer. Simulated ozone concentrations over a major fraction of East China reached high levels, all the way down to the Pearl River Delta region in the southern border. The convergence of pollutant emissions and population over the vast stretch of the geographically flat plains of East China makes the region susceptible to high-ozone exposure. During this episode, the high-03 region extended over an area >1 million km2, which hosts a population of >800 million people. Model results indicate that controlling anthropogenic NOx emissions effectively reduces the area with high-ozone exposure.

  14. The high education of optical engineering in East China

    NASA Astrophysics Data System (ADS)

    Liu, Xu; Liu, Xiangdong; Wang, Xiaoping; Bai, Jian; Liu, Yuling

    2014-07-01

    The history and the development of the high education in the field of optical engineering in the area of East China will be presented in the paper. The overall situation of research and human resource training in optics and photonics will also be reviewed, it shows that China needs lots of talents and experts in this field to support the world optical industry in East China.

  15. Assessment of heavy metal levels in surface sediments of estuaries and adjacent coastal areas in China

    NASA Astrophysics Data System (ADS)

    Liu, Xianbin; Li, Deliang; Song, Guisheng

    2017-03-01

    This article investigates the variations of contamination levels of heavy metals such as copper, lead, chromium, cadmium, zinc, arsenic, and mercury over time in surface sediments of the Changjiang River Estuary (CRE), Yellow River Estuary (YRE), Pearl River Estuary (PRE), and their adjacent coastal areas in China. The contamination factor (CF), pollution load index (PLI), and geoaccumulation index ( I geo) are used to evaluate the quality of the surface sediments in the study areas. The results showed that the CRE, YRE, and their adjacent coastal areas were at a low risk of contamination in terms of heavy metals, while the PRE and its adjacent coastal area were at a moderate level. By comparison, the concentrations of heavy metals in the surface sediments of the YRE and its adjacent coastal area were relatively lower than those in the CRE, PRE, and their adjacent coastal areas.

  16. Assessment of heavy metal levels in surface sediments of estuaries and adjacent coastal areas in China

    NASA Astrophysics Data System (ADS)

    Liu, Xianbin; Li, Deliang; Song, Guisheng

    2016-05-01

    This article investigates the variations of contamination levels of heavy metals such as copper, lead, chromium, cadmium, zinc, arsenic, and mercury over time in surface sediments of the Changjiang River Estuary (CRE), Yellow River Estuary (YRE), Pearl River Estuary (PRE), and their adjacent coastal areas in China. The contamination factor (CF), pollution load index (PLI), and geoaccumulation index (I geo) are used to evaluate the quality of the surface sediments in the study areas. The results showed that the CRE, YRE, and their adjacent coastal areas were at a low risk of contamination in terms of heavy metals, while the PRE and its adjacent coastal area were at a moderate level. By comparison, the concentrations of heavy metals in the surface sediments of the YRE and its adjacent coastal area were relatively lower than those in the CRE, PRE, and their adjacent coastal areas.

  17. Ocean Dynamics and Acoustic Variability in East China Sea

    DTIC Science & Technology

    2014-09-30

    NUMBER OF PAGES 5 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b . ABSTRACT unclassified c. THIS PAGE unclassified Standard Form 298...in Fig. 1(a) and zoomed experimental area is shown in Fig. 1( b ). (a) ( b ) Figure 1. East China Sea (ECS) with main Kuroshio Current and its branches...TAVEX2008 is marked by a solid rectangular box (red). ( b ) General experimental area in the northern East China Sea (ECS), southwest of Jeju Island, Korea. The

  18. Ocean Dynamics and Acoustic Variability in East China Sea

    DTIC Science & Technology

    2015-09-30

    Ocean ...N00014-13-1-0510 http://scrippsscholars.ucsd.edu/hcsong LONG TERM GOALS Study the effects of ocean dynamics on acoustic propagation and underwater...communication in the region of East China Sea (ECS). OBJECTIVE Conduct a joint shallow water acoustic experiment with KIOST (Korea Institute of Ocean

  19. Decadal modulation of East China winter precipitation by ENSO

    NASA Astrophysics Data System (ADS)

    Liu, Jia; Wang, Hui; Lu, Er; Kumar, Arun

    2016-11-01

    The decadal modulation of East China winter precipitation by the El Niño-Southern Oscillation (ENSO) is examined using both observational data and coupled global climate model simulations. The co-variability between 68-year (1948-2015) observed East China precipitation and tropical Pacific sea surface temperature (SST) is quantified by the singular value decomposition (SVD) method. The first SVD mode relates Southeast China winter pluvial (drought) to the tropical Pacific El Niño (La Niña) SST. A comparison between two 480-year model simulations with and without ENSO suggests that ENSO can modulate both the intensity and frequency of East China winter precipitation. In the presence of ENSO, maximum precipitation anomalies over Southeast China can be increased by 50% and largely on the interannual timescale (3-6 years). It is also demonstrated that there is an asymmetry in the precipitation and circulation responses to warm and cold phases of ENSO. The responses are sensitive to the intensity of SST anomalies during El Niño, but less sensitive to SSTs during La Niña. This sensitivity, together with the decadal variations of ENSO, helps understand the observed decadal changes in the strength of the association between wintertime tropical Pacific SST and East China precipitation. The association is relatively weak during 1948-1977 when La Niña occurred more frequently, but strong during 1978-1999 when El Niño occurred more frequently. In the last 16 years (2000-2015) the association is weakest, likely due to the weakened variability of tropical Pacific SST since 2000.

  20. Upward Continuation Apply Newly to Process Gravity Anomaly Data in the East China Sea

    NASA Astrophysics Data System (ADS)

    Han, Bo; Zhang, Xunhua; Jiang, Jinyu

    2014-05-01

    The research area lies in the East China Sea and its adjacent area and the concrete is between 120-130 degree of east longitude and 20-30 degree of north latitude and it also lies between Eurasian Plate and Pacific Plate. The structures of the area transform differently and they are namely Uplifted Zone of Zhejiang-Fujian, East China Sea Shelf Basin, Okinawa Trough Back-arc Basin, Ryukyu Arc, Ryukyu trench and Philippine Sea from west to east. Bouguer gravity anomaly can reflect deep structure characters and it is help to judge deep structures. The bouguer gravity anomalies of the area change differently from west to east. The anomalies increase gradually from land to the middle of Okinawa trough and near land anomaly contour strike accords with coastline and the middle of Okinawa trough reflect the highest anomalies in this area. Gravity anomalies re-increase from Ryukyu fore-arc basin to trench and Ryukyu island arc appears the low anomalies. Philippine Sea appears high gravity anomalies background. Upward continuation method has been used to process original gravity anomaly as a common method and its destination is to weaken local anomaly and at last strengthen deep anomaly and it's important to deep structure study. Upward 5 km, 10 km and 20 km have been used to process data and the results been compared. However, the research area is very large and the deep structure is complex, it isn't suitable to use single height to upward continuation processing bouguer gravity anomaly. Then we propose multiple upward heights continuation to process gravity data respectively in different area. We use upward 20km to process data in the area from land to the slope and upward 10km from Okinawa trough to Ryukyu island arc and upward 5km from Ryukyu trench to Philippine Sea. At last we obtain multiple upward height result and the calculated result confirms that it is fit to use this method. Gravity anomalies contours become smoother than before and the deep structures become

  1. Distribution of drifting seaweeds in eastern East China Sea

    NASA Astrophysics Data System (ADS)

    Komatsu, Teruhisa; Tatsukawa, Kenichi; Filippi, Jean B.; Sagawa, Tatsuyuki; Matsunaga, Daisuke; Mikami, Atsuko; Ishida, Kenichi; Ajisaka, Tetsuro; Tanaka, Katsuhiko; Aoki, Masakazu; Wang, Wei-Ding; Liu, Hui-Fei; Zhang, Shou-Du; Zhou, Min-Dong; Sugimoto, Takashige

    2007-09-01

    In offshore waters with relatively low primary production, drifting seaweeds composed of Sargassum species form an identical ecosystem such as an oasis in desert. Commercially important pelagic fishes such as jack mackerel ( Trachurus japonicus) and yellow tail ( Seriola quinqueradiata) spawn in East China Sea pass their juvenile period accompanying drifting seaweeds. Therefore drifting seaweeds are very important not only in offshore ecosystem but also fishery resources. However the distribution of drifting seaweeds in East China Sea has scarcely known. Then we conducted two research cruises of R/V Hakuho-Maru in May 2002 and in March 2004. During the cruises, drifting seaweeds were visually observed from the bridge and sampled with a towing net. The observation revealed that the drifting seaweeds were distributed along the front between the Kuroshio Current and coastal waters and mainly composed of one seaweed species, Sargassum horneri (Turner) C. Agardh from spring to early summer. There are no reports on geographical distribution of this species in the coasts south of southern Kyushu Island in Japan. Kuroshio Current flows northeastward there. Buoys with GPS attached to drifting seaweeds released off Zhejiang Province, China, in March 2005 to track their transport. Their positions monitored by ORBCOM satellite showed that they were transported to the area in East China Sea, where the drifting seaweeds were observed during the cruises, in 2 months. These facts suggest that S. horneri detached from Chinese coast in March or months earlier than March could be transported to fringe area of continental shelf and waters influenced by Kuroshio Current from March to May. Therefore the Sargassum forests, especially S. horneri, along the Chinese coast play a very important role in the ecosystem of the East China Sea as a source of drifting seaweeds.

  2. Benthic meiofaunal composition and community structure in the Sethukuda mangrove area and adjacent open sea, East coast of India

    NASA Astrophysics Data System (ADS)

    Thilagavathi, Balasubramanaian; Das, Bandana; Saravanakumar, Ayyappan; Raja, Kuzhanthaivel

    2011-06-01

    The ecological aspects of meiofaunal communities in the Muthupettai mangrove forest, East coast of India, has not been investigated in the last two decades. Surface water temperature ranged from 23.5 °C to 31.8 °C. Salinity varied from 24 to 34 ppt, while water pH fluctuated from 7.4 to 8.3. Dissolved oxygen concentration ranged from 3.86 to 5.33 mg/l. Meiofauna analysis in this study identified a total of 106 species from the mangrove and adjacent open sea area of Sethukuda. Among these, 56 species of foraminiferans, 20 species of nematodes, 7 species of harpacticoid copepods, 4 species of ostrocodes, and 2 species of rotifers were identified. Furthermore, a single species was identified from the following groups: ciliophora, cnidaria, gnathostomulida, insecta, propulida, bryozoa and polychaete larvae. Meiofaunal density varied between 12029 to 23493 individuals 10 cm/m2. The diversity index ranged from 3.515 to 3.680, species richness index varied from 6.384 to 8.497, and evenness index varied from 0.839 to 0876 in the mangrove area and adjacent open sea.

  3. The genus Scaphidium Olivier in East China (Coleoptera, Staphylinidae, Scaphidiinae)

    PubMed Central

    Tang, Liang; Li, Li-Zhen; He, Wen-Jia

    2014-01-01

    Abstract A review of 21 species of Scaphidium Olivier from East China is presented, including 6 new species: S. jinmingi sp. n. (Zhejiang, Anhui, Chongqing), S. crypticum sp. n. (Zhejiang, Fujian, Jiangxi, Guangxi), S. varifasciatum sp. n. (Zhejiang, An’hui), S. robustum sp. n. (Fujian, Guizhou, Chongqing, Guangxi, Yunnan), S. connexum sp. n. (Zhejiang, Fujian, Guangxi), and S. bayibini sp. n. (An’hui). New province records for S. comes Löbl, S. grande Gestro, S. sauteri Miwa & Mitono, S. formosanum Pic, S. carinense Achard, S. sinense Pic, S. delatouchei Achard, S. biwenxuani He, Tang & Li, S. klapperichi Pic, S. stigmatinotum Löbl, S. wuyongxiangi He, Tang & Li, and S. direptum Tang & Li as well as some biological notes are reported. Habitus and diagnostic characters of all species are photographed and a key to Scaphidium species of East China is provided. PMID:24843266

  4. Harvest season, high polluted season in East China

    NASA Astrophysics Data System (ADS)

    Huang, Xin; Song, Yu; Li, Mengmeng; Li, Jianfeng; Zhu, Tong

    2012-12-01

    East China, a major agricultural zone with a dense population, suffers from severe air pollution during June, the agricultural harvest season, every year. Crop burning emits tremendous amounts of combustion products into the atmosphere, not only rapidly degrading the local air quality but also affecting the tropospheric chemistry, threatening public health and affecting climate change. Recently, in mid-June 2012, crop fires left a thick pall of haze over East China. We evaluated the PM10, PM2.5 (particulates less than 10 and 2.5 μm in aerodynamic diameter) and BC (black carbon) emissions by analyzing detailed census data and moderate resolution imaging spectroradiometer (MODIS) remote sensing images and then simulated the consequent pollution using meteorological and dispersion models. The results show that the crop fires sweeping from the south to the north are responsible for the intensive air pollution during harvest season. It is necessary for scientists and governments to pay more attention to this issue.

  5. Interdecadal changes in summer TC activity in East China Sea

    NASA Astrophysics Data System (ADS)

    Choi, Ki-Seon; Cha, Yu-Mi; Kang, Sung-Dae; Kim, Hae-Dong

    2015-04-01

    The study analyzed the time series of the tropical cyclone (TC) frequencies which passed through the East China Sea between July and September from 1963 to 2012. The result of applying the statistical change-point analysis to this time series shows that a climate regime shift occurred in 1983 when the TC frequencies which pass the East China Sea area started increasing. The study then analyzed the average difference after 1983 (1984-2012) and before 1983 (1963-1983). The TC genesis frequency shows a tendency in mainly appearing in the tropical and subtropical Northwestern Pacific between 1963 and 1983 and the southern part between 1984 and 2012. The TC passage frequency shows a pattern that the TCs move from the far northeast sea of Philippines and change direction to Korea and Japan, passing through the East China Sea between 1984 and 2012. Meanwhile, the TC passage frequency shows a pattern which moves from the far southeast sea of the Philippines to southern China in the west direction in the previous period (1963-1983). These TC movement patterns coincide with the development status of the subtropical western North Pacific high (SWNPH) which averages for each period. It shows that the SWNPH in the second period stays away from the SWNPH in the second period from the northeast direction, but that the SWNPH in the first period expands to western Taiwan. This study analyzes the difference between the two periods in the 500-hPa streamline to understand the changes in such TC activities in the two groups. The anomalous anticyclonic circulations centered in the southern part of Japan are fortified in most of the subtropical Northwestern Pacific. The anomalous southerlies from the anomalous circulations are outstanding in the East China Sea area, Korea, and Japan. Therefore, the TCs generated in the tropical and subtropical Northwestern Pacific move along with the anomalous steering flow (anomalous southwesterlies) and up toward the East China Sea area, Korea, and

  6. Analysis of pecan cultivars Mahan and Western in East China.

    PubMed

    Luo, X; Li, Z; Sun, Z; Wan, X

    2016-09-16

    Pecan (Carya illinoensis) has been introduced to East China for over one hundred years, but its planting is still only occurring at a small scale. The key limiting factor is its low yield. To enhance the yield pecan in East China, two pecan cultivars, Mahan and Western, were examined. Twenty traits describing phasic development, yield, nut quality, and cultural practice were investigated. We found that pecan cultivar Mahan gives a higher yield and nut quality than cultivar Western. We recommend interplanting of cultivar Pawnee to act as a pollinator tree. Appropriate cultivation practices that can be implemented to enhance fruit yield of cultivars Mahan and Western include soil-applied paclobutrazol (PBZ) at certain concentrations, pinching, and supplementary pollination. For example, the addition of 1.25 g/m(2) of PBZ inhibits pecan branch growth and stimulates short bearing branches, which promotes fruit yield. We found that soil-applied PBZ reached optimal performance 82 days after application. A pinching length of 40 cm resulted in a fruit yield increase. In addition, grafting and transplantation may promote male flowering, but delays female flowering. These cultural practices may provide insights that can be used to improve pecan cultivation in East China.

  7. Molecular phylogeny and morphological revision of Myotis bats (Chiroptera: Vespertilionidae) from Taiwan and adjacent China.

    PubMed

    Ruedi, Manuel; Csorba, Gábor; Lin, Liang-Kong; Chou, Cheng-Han

    2015-02-20

    In taxonomic accounts, three species of Myotis have been traditionally reported to occur on the island of Taiwan: Watase's bat (M. formosus watasei Kishida), the Formosan broad-muzzled bat (M. muricola latirostris Kishida) and the Formosan mouse-eared bat (M. adversus taiwanensis Linde). The discovery in 1997 of an unknown taxon not fitting to the description of any of these species encouraged us to re-examine more thoroughly the systematics and phylogeny of Myotis bats inhabiting Taiwan. We used a combination of morphologic and molecular methods to aid the identification of the different taxa from this island and reconstruct their phylogenetic relationships. Multivariate analyses based on 17 craniodental characters of 105 specimens caught across Taiwan and further external characters allowed us to discriminate eight taxa of Myotinae co-occurring on this island. A subset of 80 specimens were further sequenced for the cytochrome b gene (1140 bp) and subjected to phylogenetic reconstructions including representative species from adjacent China and from all main lineages of the worldwide Myotis radiation. These molecular reconstructions showed that the Myotinae from Taiwan are phylogenetically diverse and are issued from several independent clades. The genetic results were completely congruent with the phenetic groupings based on craniodental and external morphology, as each of the eight Taiwanese taxa proved to be reciprocally monophyletic. Two unnamed taxa that did not fit into any of the known species were described as species new to science. Furthermore the taxon latirostris usually associated to the Asian M. muricola, was phylogenetically and morphologically distant from any other known Myotis and was assigned here to the fossil (Miocene) genus Submyotodon. Submyotodon latirostris, M. secundus sp. n. and M. soror sp. n. are endemic species from Taiwan, whereas the other five Myotis are more widespread and also found in the mainland. An identification key is

  8. Ocean pollution from land-based sources: East China Sea, China.

    PubMed

    Li, Daoji; Daler, Dag

    2004-02-01

    The environment of East China Sea (ECS) has been faced by huge stresses from anthropogenic activities and population growth in the Yangtze River drainage basin and the areas along the coasts. Improper use of natural resources and short-term economic objectives have resulted in severe environmental degradation in a fairly short time frame and the degradation has now reached a level where the health and well being of the coastal populations are threatened. The main pollutants are inorganic nitrogen, phosphate, oil hydrocarbons, organic matters and heavy metals. Nutrients cause eutrophication of the coastal waters and the estuarine area and very often stimulate the occurrence of red tides. The environmental pollution of Yangtze River basin directly impact on the state of the marine environment in the ECS. The ecosystem stability is maintained by a steady water discharge from the river, that mixes with the marine salty water in the estuary, and the sediment loads from the river that balance ocean erosion in the delta and its adjacent coastal area. The large-scale water transfer and dam constructions in the Yangtze River basin will change this basis. For the ECS the challenge is to reverse the negative processes taking place and to restore ecosystem balance. The main challenge is to integrate socioeconomic and environmental decision making in order to promote sustainable development. A better understanding of the driving forces in society that cause these environmental pressures is required in order to overcome these obstacles. International cooperation may be an important contributor to the progress and in particular provide access to financial, technological, scientific and human resource assistance.

  9. Variation of the Kuroshio axis in the East China Sea

    NASA Astrophysics Data System (ADS)

    Min, Hong Sik

    2016-04-01

    Fluctuations of the Kuroshio axis in the East China Sea and their relations to variations of temperature and sea surface height are investigated using HYCOM data. Prominent fluctuations of the Kuroshio axis are shown in the east of Taiwan, northeast of Taiwan, and southwest of Kyushu. Local changes of temperature associated with the fluctuations of the Kuroshio axis at the three regions show dipole-like structures, cooling (warming) on the immediate onshore (offshore) side of Kuroshio axis when the Kuroshio axis is located offshore. The dipole-like structures are also shown in changes of sea surface height, but their centers are not located along the Kuroshio axis but on the offshore side of the Kuroshio axis.

  10. Wintertime current meter measurements from the East China Sea

    SciTech Connect

    Trump, C.L.; Burt, W.V.

    1981-09-01

    An array of three current meters were anchored on the continental shelf of the East China Sea during the last half of February 1975 as part of the Japanese Air Mass Transformation Experiment, AMTEX-75. The results indicate that the currents are dominated by the rotational semidiurnal M/sub 2/ tidal component superimposed on a slow mean drift to the northeast. Differences in direction of several days duration between two of the current meters suggest the presence of transient mesoscale eddies or meanders in the flow regime.

  11. Plant molecular phylogeography in China and adjacent regions: Tracing the genetic imprints of Quaternary climate and environmental change in the world's most diverse temperate flora.

    PubMed

    Qiu, Ying-Xiong; Fu, Cheng-Xing; Comes, Hans Peter

    2011-04-01

    The Sino-Japanese Floristic Region (SJFR) of East Asia harbors the most diverse of the world's temperate flora, and was the most important glacial refuge for its Tertiary representatives ('relics') throughout Quaternary ice-age cycles. A steadily increasing number of phylogeographic studies in the SJFR of mainland China and adjacent areas, including the Qinghai-Tibetan-Plateau (QTP) and Sino-Himalayan region, have documented the population histories of temperate plant species in these regions. Here we review this current literature that challenges the oft-stated view of the SJFR as a glacial sanctuary for temperate plants, instead revealing profound effects of Quaternary changes in climate, topography, and/or sea level on the current genetic structure of such organisms. There are three recurrent phylogeographic scenarios identified by different case studies that broadly agree with longstanding biogeographic or palaeo-ecological hypotheses: (i) postglacial re-colonization of the QTP from (south-)eastern glacial refugia; (ii) population isolation and endemic species formation in Southwest China due to tectonic shifts and river course dynamics; and (iii) long-term isolation and species survival in multiple localized refugia of (warm-)temperate deciduous forest habitats in subtropical (Central/East/South) China. However, in four additional instances, phylogeographic findings seem to conflict with a priori predictions raised by palaeo-data, suggesting instead: (iv) glacial in situ survival of some hardy alpine herbs and forest trees on the QTP platform itself; (v) long-term refugial isolation of (warm-)temperate evergreen taxa in subtropical China; (vi) 'cryptic' glacial survival of (cool-)temperate deciduous forest trees in North China; and (vii) unexpectedly deep (Late Tertiary/early-to-mid Pleistocene) allopatric-vicariant differentiation of disjunct lineages in the East China-Japan-Korea region due to past sea transgressions. We discuss these and other consequences

  12. Chinese-U.S. sediment source-to-sink research in the east China and Yellow Seas: a brief history

    NASA Astrophysics Data System (ADS)

    Milliman, John D.; Zuosheng, Yang

    2014-11-01

    In the autumn of 1979, US oceanographers were offered a unique and in many respects a once-in-a-lifetime opportunity, as were, in hindsight, Chinese oceanographers: to help formulate and participate in the initial US-China cooperative joint oceanographic research study, as part of a cooperative research agreement signed earlier that year by the US National Oceanographic and Atmospheric Administration (NOAA) and the Chinese National Bureau of Oceanology (NBO; now known as the State Ocean Administration-SOA). Ten oceanographers from nine US oceanographic institutions and agencies traveled to China in late November with the hope-at this early stage of Chinese-US scientific relations, it was no more than a hope-to begin discussions about the possibility of a cooperative investigation of the river-estuary-shelf interactions from the Yangtze River to the adjacent East China Sea. Two years of cooperative research (1980-82) were envisioned.

  13. Detection of trends in precipitation extremes in Zhejiang, east China

    NASA Astrophysics Data System (ADS)

    Tian, Ye; Xu, Yue-Ping; Booij, M. J.; Lin, Shengji; Zhang, Qingqing; Lou, Zhanghua

    2012-01-01

    Extreme weather exerts a huge impact on human beings and it is of vital importance to study the regular pattern of meteorological and hydrological factors. In this paper, a selection of seven extreme indices is used to analyze the trend of precipitation extremes of 18 meteorological stations located in Zhejiang Province, east China using the Mann-Kendall test. Then the precipitation trends in the plum season (from May to July) and typhoon season (from August to October) are studied separately. The results show that the precipitation trend varies from east to west. There is a positive trend in the east and a negative one in the west. The largest part of Zhejiang Province shows a positive trend in heavy precipitation and the most significant upward trend is detected in Dinghai with 3.4 mm/year for precipitation on very wet days. Although the upward trend of extreme precipitation is not prevailing, the range of increase in specific areas is apparent, like Dinghai with 1.3 mm/year. Precipitation intensity exhibits an upward trend in most areas and a typical upward trend can be found in Dachendao, Tianmushan, and Yuhuan with 0.04, 0.02, and 0.05 mm/year respectively. Precipitation intensity in both plum and typhoon seasons has increased too, especially for the coastal stations.

  14. 77 FR 13171 - China North East Petroleum Holdings Limited, Order of Suspension of Trading

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-05

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION China North East Petroleum Holdings Limited, Order of Suspension of Trading March 1, 2012. It... accurate information concerning the securities of China North East Petroleum Holdings Limited (``NEP''),...

  15. Dramatic declines in Euphausia pacifica abundance in the East China Sea: response to recent regional climate change.

    PubMed

    Xu, Zhao-Li; Zhang, Dong

    2014-03-01

    As with other marine ecosystems around the world, water temperature has been anomalously warm in recent years in the East China Sea. We analyzed historical data to explore the effects of climatic change on the abundance and distribution variation of Euphausia pacifica in the East China Sea (the Changjiang River estuary and adjacent areas). In 1959, the highest abundance occurred in the spring and autumn, and this krill species was still abundant in May 1974; however, its abundance was significantly reduced in 2002, markedly in spring. Euphausia pacifica was the numerically dominant euphausiid in the East China Sea in 1959. Its mean abundance was up to 1.91 ind m(-3) and 1.64 ind/m(3) in 1959 and 1974, respectively; however, this figure decreased to 0.36 ind m(-3) in 2002. Since 2003, the abundances have been near zero in the most years. Both inter-annual (between November 1959 and 2002) and inter-monthly (between May and June 1959) comparisons suggest that E. pacifica has had a temperature-driven northward movement in response to rising sea surface temperature, especially the positive anomalies since 1997. However, E. pacifica did not come back to the previous habitat when temperature became relative cold. Hence additional factors affecting the E. pacifica distribution and abundance need to be investigated in the future study.

  16. Pollution from China increases cloud droplet number, suppresses rain over the East China Sea

    SciTech Connect

    Bennartz, Ralph; Fan, Jiwen; Rausch, J; Leung, Lai-Yung R; Heidinger, Andrew K

    2011-05-18

    Rapid economic growth over the last 30 years in China has led to a significant increase in aerosol loading, which is mainly due to the increased emissions of its precursors such as SO2 and NOx. Here we show that these changes significantly affect wintertime clouds and precipitation over the East China Sea downwind of major emission sources. Satellite observations show an increase of cloud droplet number concentration from less than 200 cm-3 in the 1980s to more than 300 cm-3 in 2005. In the same time period, precipitation frequency reported by voluntary ship observers was reduced from more than 30% to less than 20% of the time. A back trajectory analysis showed the pollution in the investigation area to originate from the Shanghai-Nanjing and Jinan industrial areas. A model sensitivity study was performed, isolating the effects of changes in emissions of the aerosol precursors SO2 and NOx on clouds and precipitation using a state-of-the-art mesocale model including chemistry and aerosol indirect effects. Similar changes in cloud droplet number concentration over the East China Sea were obtained when the current industrial emissions in China were reduced to the 1980s levels. Simulated changes in precipitation were somewhat smaller than the observed changes but still significant. Citation: Bennartz, R., J. Fan, J. Rausch, L. R. Leung, and A. K. Heidinger (2011), Pollution from China increases cloud droplet number, suppresses rain over the East China Sea, Geophys. Res. Lett., 38, L09704, doi:10.1029/ 2011GL047235.

  17. Characteristics of Cloud Radiation Forcing over East China.

    NASA Astrophysics Data System (ADS)

    Wang, Wei-Chyung; Gong, Wei; Kau, Wen-Shung; Chen, Cheng-Ta; Hsu, Huang-Hsiung; Tu, Chia-Hsiu

    2004-02-01

    Observations indicate that the East Asian summer monsoon (EASM) exhibits distinctive characteristics of large cloud amounts with associated heavy and persistent rainfall, although short breaks for clear sky usually occur. Consequently, the effects of cloud radiation interactions can play an important role in the general circulation of the atmosphere and, thus, the evolution of the EASM. In this note, as a first step toward studying the topic, the 5-yr (January 1985 December 1989) Earth Radiation Budget Experiment (ERBE) dataset is used to show the spatial and temporal patterns of both shortwave (SW) and longwave (LW) cloud radiative forcing (CRF) at the top of the atmosphere over east China, and to compare the observed features with Atmospheric Model Intercomparison Project-II (AMIP-II) simulations with the University at Albany, State University of New York (SUNYA) Community Climate Model 3 (CCM3) and the ECHAM4 general circulation models.The observations indicate that the net CRF provides a cooling effect to the atmosphere surface climate system, dominated by the SW CRF cooling (albedo effect) with partial compensation from the LW CRF warming (greenhouse effect). The SW CRF shows a strong seasonal cycle, and its peak magnitude is particularly large, 110 W m-2, for south China and the Yangtze Huai River valley (YHRV) during May and June, while the LW CRF is about 50 W m-2 for the same months with a weak dependence on the latitudes and seasons. These characteristics are in sharp contrast to the Northern Hemispheric zonal means of the same latitude bands and seasons, thus implying a unique role for cloud radiation interaction in east China. Both model simulations show similar observed characteristics, although biases exist. For example, in May, the ECHAM4 underestimates the SW CRF while the SUNYA CCM3 simulates a significantly larger value, both attributed to the respective biases in the simulated total cloud cover. Model-to-observation comparisons of the association

  18. Pollution from China increases cloud droplet number, suppresses rain over the East China Sea

    NASA Astrophysics Data System (ADS)

    Bennartz, Ralf; Fan, Jiwen; Rausch, John; Leung, L. Ruby; Heidinger, Andrew K.

    2011-05-01

    Rapid economic growth over the last 30 years in China has led to a significant increase in aerosol loading, which is mainly due to the increased emissions of its precursors such as SO2 and NOx. Here we show that these changes significantly affect wintertime clouds and precipitation over the East China Sea downwind of major emission sources. Satellite observations show an increase of cloud droplet number concentration from less than 200 cm-3 in the 1980s to more than 300 cm-3 in 2005. In the same time period, precipitation frequency reported by voluntary ship observers was reduced from more than 30% to less than 20% of the time. A back trajectory analysis showed the pollution in the investigation area to originate from the Shanghai-Nanjing and Jinan industrial areas. A model sensitivity study was performed, isolating the effects of changes in emissions of the aerosol precursors SO2 and NOx on clouds and precipitation using a state-of-the-art mesocale model including chemistry and aerosol indirect effects. Similar changes in cloud droplet number concentration over the East China Sea were obtained when the current industrial emissions in China were reduced to the 1980s levels. Simulated changes in precipitation were somewhat smaller than the observed changes but still significant.

  19. Environmental consequences of rapid urbanization in zhejiang province, East china.

    PubMed

    Yang, Xuchao; Yue, Wenze; Xu, Honghui; Wu, Jingsheng; He, Yue

    2014-07-11

    Since reforms carried out in the late 1970s, China has experienced unprecedented rates of urban growth. Remote sensing data and surface observational data are used to investigate the urbanization process and related environmental consequences, focusing on extreme heat events and air pollution, in Zhejiang Province (ZJP, East China). Examination of satellite-measured nighttime light data indicates rapid urbanization in ZJP during the past decade, initially forming three urban clusters. With rapid urban sprawl, a significant Urban Heat Island (UHI) effect has emerged. During extreme heat events in summer, the UHI effect significantly exacerbates nocturnal heat stress in highly urbanized areas. Taking a long-term view, urbanization also causes additional hot days and hot degree days in urban areas. Urbanization also imposes a heavy burden on local and regional air quality in ZJP. Degraded visibility and an increase in haze days are observed at most meteorological stations, especially in the three urban clusters. The results show that urbanization has led to serious environmental problems in ZJP, not only on the city scale, but also on the regional scale. Maintaining a balance between the continuing process of urbanization and environmental sustainability is a major issue facing the local government.

  20. Environmental Consequences of Rapid Urbanization in Zhejiang Province, East China

    PubMed Central

    Yang, Xuchao; Yue, Wenze; Xu, Honghui; Wu, Jingsheng; He, Yue

    2014-01-01

    Since reforms carried out in the late 1970s, China has experienced unprecedented rates of urban growth. Remote sensing data and surface observational data are used to investigate the urbanization process and related environmental consequences, focusing on extreme heat events and air pollution, in Zhejiang Province (ZJP, East China). Examination of satellite-measured nighttime light data indicates rapid urbanization in ZJP during the past decade, initially forming three urban clusters. With rapid urban sprawl, a significant Urban Heat Island (UHI) effect has emerged. During extreme heat events in summer, the UHI effect significantly exacerbates nocturnal heat stress in highly urbanized areas. Taking a long-term view, urbanization also causes additional hot days and hot degree days in urban areas. Urbanization also imposes a heavy burden on local and regional air quality in ZJP. Degraded visibility and an increase in haze days are observed at most meteorological stations, especially in the three urban clusters. The results show that urbanization has led to serious environmental problems in ZJP, not only on the city scale, but also on the regional scale. Maintaining a balance between the continuing process of urbanization and environmental sustainability is a major issue facing the local government. PMID:25019266

  1. Late Cenozoic evolution of the East China continental margin: Insights from seismic, gravity, and magnetic analyses

    NASA Astrophysics Data System (ADS)

    Shang, Lu-Ning; Zhang, Xun-Hua; Jia, Yong-Gang; Han, Bo; Yang, Chuan-Sheng; Geng, Wei; Pang, Yu-Mao

    2017-02-01

    Seismic reflection profiles reveal the structural characteristics beneath the East China Sea shelf margin and the Okinawa Trough, and provide new constraints on the Late Cenozoic evolution of the East China continental margin. The Frontal Shelf Basin between the Taiwan-Sinzi Uplift and the trough axis occupies the western half of the Northern-Middle Okinawa Trough. In this basin, the Middle-Late Miocene sediments are confined to grabens or half-grabens dominated by listric faults, whereas the overlying Pliocene-Quaternary sequence is characterized by a uniform thickness and dense planar-type faults, suggesting that rifting of the Northern-Middle Okinawa Trough initiated during the Middle Miocene but slowed down during the earliest Pliocene. Since that time, the opening of the Okinawa Trough has been dominated by diffuse rifting. The Southern Okinawa Trough is predominately filled by Quaternary sediments, indicating that its back-arc rifting began during the earliest Pleistocene. Contractional structures identified in the pre-Quaternary sequence beneath the continental slope, along with an erosional Pleistocene-pre-Pleistocene unconformity in the Southern Okinawa Trough, demonstrate the existence of pre-rifting compression and uplifting in this region. We use this evidence and previously published results, to propose an evolutionary model of the East China continental margin during the Late Cenozoic. The Northern-Middle Okinawa Trough began rifting during the Middle Miocene on a paleo-uplift. The Luzon Arc initially impinged upon the Eurasian continental margin during the Late Miocene near the southeastern end of the Miyako Fault Belt and activated the proto-Taiwan Orogeny in today's Southern Okinawa Trough and adjacent regions. During the Late Miocene-Pliocene, the orogeny quickly propagated southwestward along with the west-northwest-moving Philippine Sea Plate. Subsequently, the rifting of the Southern Okinawa Trough was initiated during the earliest Pleistocene

  2. Dike Interactions along the East Pacific Rise: Can Dike-Induced Static Stress Changes Trigger Diking at Adjacent Ridge Segments?

    NASA Astrophysics Data System (ADS)

    Applebee, G. M.; Cormier, M.

    2008-12-01

    Although the physical conditions that control dike intrusion at spreading centers are subject to debate, it is generally agreed these include a crustal section stressed close to failure and an overpressured magma chamber. Along the East Pacific Rise (EPR), fast spreading rates (100-150 mm/yr) and the presence of a narrow, shallow and nearly continuous melt lens (0.5-1.5 km wide, 1-1.5 km deep) imply that these two criteria are frequently met. Hence, a small incremental stress change at the EPR axis may be sufficient to trigger dike intrusion along a "4rth-order segment"- the elemental 10-20 km-long section of ridge that ruptures in a given volcanic episode. We use the COULOMB 3.1 software to investigate whether static stress changes induced by dike emplacement at a 4rth-order segment may be sufficient to trigger diking at neighboring segments. In the absence of any observational data about dike triggering, we adopt some conclusions from studies of stress transfer in earthquake sequences, and assume that static stress changes of 1-2 bar can promote dike intrusion in a favorably pre-stressed crust. Modeling results indicate that tensile stress changes of 1-2 bars extend as far as 10 km beyond the tip of a newly emplaced dike, suggesting that along the EPR, the intrusion of a dike may be sufficient to promote concomitant diking at adjacent 4rth-order segments. This 10 km distance varies only slightly when experimenting with reasonable dike geometries: dike heights of 1-1.5 km and widths of 0.5-2 m are used, as narrowly constrained from observations at the EPR. Hence, provided that a second-order segment (50 km-long or more) is critically stressed and that the subjacent magma chamber is overpressured, eruption of a 4rth-order segment somewhere along that segment may trigger a sequence of diking events on a relatively short time-scale. This model may soon be tested at the EPR "Integrated Study Site" at 9N, by a series of recent and on-going experiments funded by the NSF

  3. Wave retrieval from SAR imagery in the East China Sea

    NASA Astrophysics Data System (ADS)

    Lou, Xiulin; Chang, Junfang; Liu, Xiaoyan

    2015-12-01

    Synthetic aperture radar (SAR) plays an important role in measuring directional ocean wave spectra with continuous and global coverage. In this article, satellite SAR images were used to estimate the wave parameters in the East China Sea. The Max-Planck Institut (MPI) method was applied to retrieve directional wave spectra from the SAR imagers with the Simulating WAves Nearshore (SWAN) model data as the first guess wave spectra. In order to validate the SAR retrieved wave spectra, a set of buoy measurements during the SAR imaging times was collected and used. The SAR retrieved significant wave heights (SWHs) were analyzed against the buoy measurements to assess the wave retrieval of this study. The root-mean-square error between the SAR SWHs and the buoy measurements is 0.25 m, which corresponds to a relative error of 12%. The case study here shows that the SWAN model data is a potential first guess wave spectra source to the MPI method to retrieve ocean wave spectra from SAR imagery.

  4. Fatty acid composition of surface sediments in the subtropical Pearl River estuary and adjacent shelf, Southern China

    NASA Astrophysics Data System (ADS)

    Hu, Jianfang; Zhang, Hongbo; Peng, Ping'an

    2006-01-01

    Surface sediments (10 cm) of the subtropical Pearl River estuary and adjacent shelf, Southern China were collected. Fatty acids and compound-specific carbon isotopic analyses were determined to infer their sources and biogeochemical cycle of this lipid in the subtropical Pearl River estuary and adjacent northern South China Sea (SCS). The total concentrations of fatty acids ranged from ˜1.28 to ˜42.25 μg g -1 dry weight. The levels of polyunsaturated fatty acids (PUFA) were low (0.2-4.8% of total fatty acids), suggesting that fatty acids derived from algae were effectively recycled during the whole settling and depositing process. Bacterial fatty acids were significantly high and terrigenous fatty acids were low in the sediments. Principal component analysis (PCA) of the data also indicates that a clear separation of the biogeochemical sources can be seen. The δ13C values of bacterial fatty acids, i.e., i/ aiC 15 (-22.9‰ to -29.4‰) suggest that bacteria within the sediments mainly utilize a labile pool of organic matter derived from algae for their growth in the subtropical Pearl River estuary system.

  5. Holocene paleomagnetic secular variation records from the East China Sea

    NASA Astrophysics Data System (ADS)

    Zheng, Y.; Zheng, H.; Kissel, C.; Laj, C. E.; Deng, C.

    2011-12-01

    Paleomagnetic study on marine sediments can provide continuous, high-resolution records of short-term fluctuations of the Earth's magnetic field, which can be used for inter-core correlations at regional scale. However, Holocene paleomagnetic secular variation (PSV) records from marine sediment are still rare. Detailed paleomagnetic and rock magnetic studies were conducted on u-channel samples from rapidly deposited sediment core MD06-3040 (27.72°N, 121.78°E; 46 m water depth), on the East China Sea (ECS) inner continental shelf Holocene marine sequence, during IMAGES XIV Marco Polo 2 cruise on the R. V. Marion Dufresne (IPEV). The 19.22 m long core spans the entire Holocene, with theoretical high-resolution of about 20-year for paleomagnetic studies, and paleomagnetic secular variation (PSV) for the last 7500 years was retrieved from the uppermost 15.8 m fine-grained sediments. The dominant carrier of the remanent magnetization is magnetite, with some contributions from iron sulfide, such as greigite below 3.5 m, due to post-depositional diagenesis. The Characteristic Remanent magnetization (ChRM) is well defined by a single magnetization component and Maximum Angular Deviations (MAD) lower than 5°. Therefore, the information of paleomagnetic directions is still preserved after diagenetic alteration. Inclination of core MD06-3040 presents seven relatively high peaks, and declination presents four obvious eastern ward drifts during the last 7500 years. These variations can be well compared to that obtained from lakes in Japan, and some features are also comparable to the records from Europe with temporal offset. The power spectrum analysis shows that the inclination has significant power at the period of ~660 years, and declination at the period of ~3500 years and 1300 years. These periods are similar to that from Japan and North America, in which the period of ~1300 years for declination has been reported in many areas around the world. The observed PSV from

  6. Petroleum system of the Shelf Rift Basin, East China Sea

    SciTech Connect

    Cunningham, A.C.; Armentrout, J.M.; Prebish, M.

    1996-12-31

    The Tertiary section of the Oujioang and Quiontang Depressions of the East China Sea Basin consists of at least eight rift-related depositional sequences identified seismically by regionally significant onlap and truncation surfaces. These sequences are calibrated by several wells including the Wenzhou 6-1-1 permitting extrapolation of petroleum system elements using seismic facies analysis. Gas and condensate correlated to non-marine source rocks and reservoired in sandstone at the Pinghu field to the north of the study area provides an known petroleum system analogue. In the Shelf Rift Basin, synrift high-amplitude parallel reflections within the graben axes correlate with coaly siltstone strata and are interpreted as coastal plain and possibly lacustrine facies with source rock potential. Synrift clinoform seismic facies prograding from the northwest footwall correlate with non-marine to marginal marine conglomerate, sandstone and siltstone, and are interpreted as possible delta or fan-delta facies with reservoir potential although porosity and permeability is low within the Wenzhou 6-1-1 well. Post-rift thermal sag sequences are characterized by parallel and relatively continuous seismic reflections and locally developed clinoform packages. These facies correlate with porous and permeable marine sandstone and siltstone. Shales of potential sealing capacity occur within marine flooding intervals of both the synrift and post-rift sequences. Traps consist of differentially rotated synrift fill, and post-rift inversion anticlines. Major exploration risk factors include migration from the synrift coaly source rocks to the post-rift porous and permeable sandstones, and seismic imaging and drilling problems associated with extensive Tertiary igneous intrusions.

  7. Petroleum system of the Shelf Rift Basin, East China Sea

    SciTech Connect

    Cunningham, A.C.; Armentrout, J.M.; Prebish, M. )

    1996-01-01

    The Tertiary section of the Oujioang and Quiontang Depressions of the East China Sea Basin consists of at least eight rift-related depositional sequences identified seismically by regionally significant onlap and truncation surfaces. These sequences are calibrated by several wells including the Wenzhou 6-1-1 permitting extrapolation of petroleum system elements using seismic facies analysis. Gas and condensate correlated to non-marine source rocks and reservoired in sandstone at the Pinghu field to the north of the study area provides an known petroleum system analogue. In the Shelf Rift Basin, synrift high-amplitude parallel reflections within the graben axes correlate with coaly siltstone strata and are interpreted as coastal plain and possibly lacustrine facies with source rock potential. Synrift clinoform seismic facies prograding from the northwest footwall correlate with non-marine to marginal marine conglomerate, sandstone and siltstone, and are interpreted as possible delta or fan-delta facies with reservoir potential although porosity and permeability is low within the Wenzhou 6-1-1 well. Post-rift thermal sag sequences are characterized by parallel and relatively continuous seismic reflections and locally developed clinoform packages. These facies correlate with porous and permeable marine sandstone and siltstone. Shales of potential sealing capacity occur within marine flooding intervals of both the synrift and post-rift sequences. Traps consist of differentially rotated synrift fill, and post-rift inversion anticlines. Major exploration risk factors include migration from the synrift coaly source rocks to the post-rift porous and permeable sandstones, and seismic imaging and drilling problems associated with extensive Tertiary igneous intrusions.

  8. Antimony and arsenic biogeochemistry in the East China Sea

    NASA Astrophysics Data System (ADS)

    Ren, Jing-Ling; Zhang, Xu-Zhou; Sun, You-Xu; Liu, Su-Mei; Huang, Daji; Zhang, Jing

    2016-02-01

    The biogeochemical cycles of the metalloid elements arsenic and antimony in the East China Sea (ECS), one of the most important marginal seas for western Pacific, were examined in May 2011. Dissolved inorganic arsenic (As(V) and As(III)) and antimony (Sb(V) and Sb(III)) species were determined by selective hydride generation-atomic fluorescence spectrometry (HG-AFS). Results show that total dissolved inorganic arsenic (TDIAs; [TDIAs]=[As(V)]+[As(III)]) were moderately depleted in the surface water and enriched in the deep water. Arsenite (As(III)) showed different vertical profiles with that of TDIAs, with significant surface enrichment in the middle shelf region where the concentrations of phosphate were extremely low. Speciation of dissolved arsenic was subtly controlled by the stoichiometric molar ratio of arsenate (As(V)) to phosphate. The average As(V)/P ratio for the ECS in spring 2011 was 10.8×10-3, which is higher than previous results and indicates the arsenate stress. The concentrations of total dissolved inorganic antimony (TDISb; [TDISb]=[Sb(V)]+[Sb(III)]) were high near the Changjiang Estuary and the coastal area of Hangzhou Bay and decreased moderately off the coast. TDISb displayed moderate conservative behavior in the ECS that confirms by the correlations with salinity and dissolved aluminum. Different with that of As(III), antimonite (Sb(III)) concentrations were extremely lower in the ECS, with relative higher concentration appeared at the bottom layer which indicates the contribution from sediment-water interface. A preliminary box model was established to estimate the water-mass balance and antimony budgets for the ECS. Compared with other areas in the world, the concentrations of dissolved inorganic arsenic and antimony in the ECS remain at natural levels.

  9. Suspended sediment concentration mapping based on the MODIS satellite imagery in the East China inland, estuarine, and coastal waters

    NASA Astrophysics Data System (ADS)

    Yang, Xianping; Sokoletsky, Leonid; Wei, Xiaodao; Shen, Fang

    2017-01-01

    The purpose of this research is to improve the retrieval accuracy for the suspended sediment concentration (SSC) from in situ and satellite remote sensing measurements in turbid East China estuarine and coastal waters. For this aim, three important tasks are formulated and solved: 1) an estimation of remote-sensing reflectance spectra R rs(λ) after atmospheric correction; 2) an estimation of R rs(λ) from the radiometric signals above the air-water surface; and 3) an estimation of SSC from R rs(λ). Six different models for radiometric R rs(λ) determination and 28 models for SSC versus R rs(λ) are analyzed based on the field observations made in the Changjiang River estuary and its adjacent coastal area. The SSC images based on the above-mentioned analysis are generated for the area.

  10. Processes and mechanisms of persistent extreme precipitation events in East China

    NASA Astrophysics Data System (ADS)

    Zhai, Panmao; Chen, Yang

    2014-11-01

    This study mainly presents recent progresses on persistent extreme precipitation events (PEPEs) in East China. A definition focusing both persistence and extremity of daily precipitation is firstly proposed. An identification method for quasi-stationary regional PEPEs is then designed. By utilizing the identified PEPEs in East China, typical circulation configurations from the lower to the upper troposphere are confirmed, followed by investigations of synoptic precursors for key components with lead time of 1-2 weeks. Two characteristic circulation patterns responsible for PEPEs in East China are identified: a double blocking high type and a single blocking high type. They may account for occurrence of nearly 80% PEPEs during last 60 years. For double blocking high type, about two weeks prior to PEPEs, two blockings developed and progressed towards the Ural Mountains and the Sea of Okhotsk, respectively. A northwestward progressive anomalous anticyclone conveying abundant moisture and eastward-extended South Asia High favoring divergence can be detected about one week in advance. A dominant summertime teleconnection over East Asia, East Asia/ Pacific (EAP) pattern, is deemed as another typical regime inducing PEPEs in the East China. Key elements of the EAP pattern initiated westward movement since one week prior to PEPEs. Eastward energy dispersion and poleward energy dispersion contributed to early development and subsequent maintenance of this teleconnection pattern, respectively. These typical circulation patterns and significant precursors may offer local forecasters some useful clues in identifying and predicting such high-impact precipitation events about 1-2 weeks in advance.

  11. Teaching West in the East: An American University in China

    ERIC Educational Resources Information Center

    Ozturgut, Osman

    2007-01-01

    Having closed its door to Western ideas for centuries, China has always presented itself as a puzzle both for academicians and politicians. Westerners, though, have always been attracted by the natural resources and human power that China offers to the capitalistic world. This study explores the entrance of Western ideas in China from an…

  12. Distinguishing Terrestrial Organic Carbon in Marginal Sediments of East China Sea and Northern South China Sea

    NASA Astrophysics Data System (ADS)

    Kandasamy, Selvaraj; Lin, Baozhi; Wang, Huawei; Liu, Qianqian; Liu, Zhifei; Lou, Jiann-Yuh; Chen, Chen-Tung Arthur; Mayer, Lawrence M.

    2016-04-01

    Knowledge about the sources, transport pathways and behavior of terrestrial organic carbon in continental margins adjoining to large rivers has improved in recent decades, but uncertainties and complications still exist with human-influenced coastal regions in densely populated wet tropics and subtropics. In these regions, the monsoon and other episodic weather events exert strong climatic control on mineral and particulate organic matter delivery to the marginal seas. Here we investigate elemental (TOC, TN and bromine-Br) and stable carbon isotopic (δ13C) compositions of organic matter (OM) in surface sediments and short cores collected from active (SW Taiwan) and passive margin (East China Sea) settings to understand the sources of OM that buried in these settings. We used sedimentary bromine to total organic carbon (Br/TOC) ratios to apportion terrigenous from marine organic matter, and find that Br/TOC may serve as an additional, reliable proxy for sedimentary provenance in both settings. Variations in Br/TOC are consistent with other provenance indicators in responding to short-lived terrigenous inputs. Because diagenetic alteration of Br is insignificant on shorter time scales, applying Br/TOC ratios as a proxy to identify organic matter source along with carbon isotope mixing models may provide additional constraints on the quantity and transformation of terrigenous organics in continental margins. We apply this combination of approaches to land-derived organic matter in different depositional environments of East Asian marginal seas.

  13. [Source and distribution characteristic of atmospheric organochlorine pesticides in the Pearl River Estuary and adjacent South China Sea].

    PubMed

    Liu, Guo-qing; Zhang, Gan; Li, Jun; Liu, Xiang; Peng, Xian-zhi; Zou, Shi-chun; Qi, Shi-hua

    2008-12-01

    Ship-board air samples were collected during the winter and spring cruise to the Pearl River Estuary (PRE) and adjacent South China Sea (SCS) in 2003 and were analyzed for organochlorine pesticides (OCPs). Meanwhile, air samples were collected at land-based sites in Guangzhou and Zhongshan for comparison. Results indicated that the detected OCPs were mainly of HCHs, DDTs and chlordane, its concentration ranged between 13-99, 73-390, 63-224 pg/m3 and 10-106, 429-1003, 1724-9638 pg/m3 during the winter and spring cruise, respectively. In general, the concentrations of OCPs were higher during spring cruise than in winter cruise. The measured OCPs concentration in the atmosphere over the PRE and adjacent SCS were found higher at sites close to continent and lower in outer sea, it is suggested that land-based source were to play a key role in the delivery of atmospheric OCPs. The alpha-HCH concentrations had significantly declined, higher gamma-HCH level may attribute to the present usage of lindane. Dicofol application and antifouling paints for fishing ships was suggested to be the important current "fresh" DDT source. The observed high level of chlordane during spring cruise could be related to the large amount usage of chlordane for termite control, as well as the long range transport from the west pacific region.

  14. Meiofauna assemblages of the Condor Seamount (North-East Atlantic Ocean) and adjacent deep-sea sediments

    NASA Astrophysics Data System (ADS)

    Zeppilli, Daniela; Bongiorni, Lucia; Cattaneo, Antonio; Danovaro, Roberto; Santos, Ricardo Serrão

    2013-12-01

    Seamounts are currently considered hotspots of biodiversity and biomass for macro- and megabenthic taxa, but knowledge of meiofauna is still limited. Studies have revealed the existence of highly diverse meiofauna assemblages; however most data are mainly qualitative or focused only on specific groups, thus preventing comparisons among seamounts and with other deep-sea areas. This study, conducted on Condor Seamount (Azores, North-East Atlantic Ocean), describes variation in abundance, biomass, community structure and biodiversity of benthic meiofauna from five sites located on the Condor Seamount: and one site away from the seamount. While the summit of the seamount hosted the highest alpha biodiversity, the flanks and the bases showed a rich meiofauna assemblage in terms of abundance and biomass. The observed marked differences in grain size composition of sediments reflected the oceanographic conditions impacting different sectors of the Condor seamount, and could play an important role in the spatial distribution of different meiofaunal taxa. Trophic conditions (biochemical composition of organic matter) explained 78% of the variability in the meiofauna biomass pattern while sediment grain influenced the vertical distribution of meiofauna and only partially explained meiofaunal taxa composition. This study provides a further advancement in the knowledge of meiofaunal communities of seamounts. Only a deeper understanding of the whole benthic communities (including meiofauna) will allow to elaborate effective management and conservation tools for seamount ecosystems.

  15. Genetic Structure and Evolutionary History of Three Alpine Sclerophyllous Oaks in East Himalaya-Hengduan Mountains and Adjacent Regions

    PubMed Central

    Feng, Li; Zheng, Qi-Jian; Qian, Zeng-Qiang; Yang, Jia; Zhang, Yan-Ping; Li, Zhong-Hu; Zhao, Gui-Fang

    2016-01-01

    The East Himalaya-Hengduan Mountains (EH-HM) region has a high biodiversity and harbors numerous endemic alpine plants. This is probably the result of combined orographic and climate oscillations occurring since late Tertiary. Here, we determined the genetic structure and evolutionary history of alpine oak species (including Quercus spinosa, Quercus aquifolioides, and Quercus rehderiana) using both cytoplasmic-nuclear markers and ecological niche models (ENMs), and elucidated the impacts of climate oscillations and environmental heterogeneity on their population demography. Our results indicate there were mixed genetic structure and asymmetric contemporary gene flow within them. The ENMs revealed a similar demographic history for the three species expanded their ranges from the last interglacial (LIG) to the last glacial maximum (LGM), which was consistent with effective population sizes changes. Effects of genetic drift and fragmentation of habitats were responsible for the high differentiation and the lack of phylogeographic structure. Our results support that geological and climatic factors since Miocene triggered the differentiation, evolutionary origin and range shifts of the three oak species in the studied area and also emphasize that a multidisciplinary approach combining molecular markers, ENMs and population genetics can yield deep insights into diversification and evolutionary dynamics of species. PMID:27891142

  16. Genetic Structure and Evolutionary History of Three Alpine Sclerophyllous Oaks in East Himalaya-Hengduan Mountains and Adjacent Regions.

    PubMed

    Feng, Li; Zheng, Qi-Jian; Qian, Zeng-Qiang; Yang, Jia; Zhang, Yan-Ping; Li, Zhong-Hu; Zhao, Gui-Fang

    2016-01-01

    The East Himalaya-Hengduan Mountains (EH-HM) region has a high biodiversity and harbors numerous endemic alpine plants. This is probably the result of combined orographic and climate oscillations occurring since late Tertiary. Here, we determined the genetic structure and evolutionary history of alpine oak species (including Quercus spinosa, Quercus aquifolioides, and Quercus rehderiana) using both cytoplasmic-nuclear markers and ecological niche models (ENMs), and elucidated the impacts of climate oscillations and environmental heterogeneity on their population demography. Our results indicate there were mixed genetic structure and asymmetric contemporary gene flow within them. The ENMs revealed a similar demographic history for the three species expanded their ranges from the last interglacial (LIG) to the last glacial maximum (LGM), which was consistent with effective population sizes changes. Effects of genetic drift and fragmentation of habitats were responsible for the high differentiation and the lack of phylogeographic structure. Our results support that geological and climatic factors since Miocene triggered the differentiation, evolutionary origin and range shifts of the three oak species in the studied area and also emphasize that a multidisciplinary approach combining molecular markers, ENMs and population genetics can yield deep insights into diversification and evolutionary dynamics of species.

  17. Sulfur dioxide emissions in China and sulfur trends in East Asia since 2000.

    SciTech Connect

    Lu, Z.; Streets, D. G.; Zhang, Q.; Wang, S.; Carmichael, G. R.; Cheng, Y. F.; Wei, C.; Chin, M.; Diehl, T.; Tan, Q.; Decision and Information Sciences; Tsinghua Univ.; Univ. of Iowa; NASA Goddard Space Flight Center

    2010-01-01

    With the rapid development of the economy, the sulfur dioxide (SO{sub 2}) emission from China since 2000 is of increasing concern. In this study, we estimate the annual SO{sub 2} emission in China after 2000 using a technology-based methodology specifically for China. From 2000 to 2006, total SO{sub 2} emission in China increased by 53%, from 21.7 Tg to 33.2 Tg, at an annual growth rate of 7.3%. Emissions from power plants are the main sources of SO{sub 2} in China and they increased from 10.6 Tg to 18.6 Tg in the same period. Geographically, emission from north China increased by 85%, whereas that from the south increased by only 28%. The emission growth rate slowed around 2005, and emissions began to decrease after 2006 mainly due to the wide application of flue-gas desulfurization (FGD) devices in power plants in response to a new policy of China's government. This paper shows that the trend of estimated SO{sub 2} emission in China is consistent with the trends of SO{sub 2} concentration and acid rain pH and frequency in China, as well as with the increasing trends of background SO{sub 2} and sulfate concentration in East Asia. A longitudinal gradient in the percentage change of urban SO{sub 2} concentration in Japan is found during 2000-2007, indicating that the decrease of urban SO{sub 2} is lower in areas close to the Asian continent. This implies that the transport of increasing SO{sub 2} from the Asian continent partially counteracts the local reduction of SO{sub 2} emission downwind. The aerosol optical depth (AOD) products of Moderate Resolution Imaging Spectroradiometer (MODIS) are found to be highly correlated with the surface solar radiation (SSR) measurements in East Asia. Using MODIS AOD data as a surrogate of SSR, we found that China and East Asia excluding Japan underwent a continuous dimming after 2000, which is in line with the dramatic increase in SO{sub 2} emission in East Asia. The trends of AOD from both satellite retrievals and model over

  18. Circulation system configuration characteristics of four rainfall patterns in summer over the East China

    NASA Astrophysics Data System (ADS)

    Zhao, Junhu; Yang, Liu; Feng, Guolin

    2017-01-01

    In this study, the simultaneous atmospheric circulation system configuration characteristics of the four rainfall patterns (FRP) over the East China during the period 1951-2015 are analyzed in order to investigate their formation mechanisms. The results confirm that the FRP possess obvious differences in the upper-level, middle-level, and lower-level troposphere. In northern China rainfall pattern (NCP) years, the East Asian subtropical westerly jet stream (EAJS) shows a northward trend, with a higher intensity than normal; the blocking high (BH) in the mid-high latitudes is inactive; and the western Pacific subtropical high (WPSH) tends to be stronger, with a location to the north of its normal position. The East Asian summer monsoon (EASM) is stronger, which promotes vapor transport to northern China, and this leads to increased rainfall. In intermediate rainfall pattern (IRP) years, the EAJS position is close to that in normal years; the BH is inactive; the WPSH tends to be weaker, with a location to the east of its normal position; and the EASM is stronger, which is conducive to increased rainfall over the Huaihe River Basin. In Yangtze River rainfall pattern (YRP) years, the circulations are found to be almost opposite in their features to those in NCP years. In South China rainfall pattern (SCP) years, the circulations are found to be almost opposite in their features to those in IRP years. This leads to increased rainfall over South China. Therefore, the different circulation system configuration characteristics lead to the different rainfall patterns.

  19. A preliminary study of the microbial resources and their biological activities of the East china sea.

    PubMed

    Lu, Xiaoling; Liu, Xiaoyu; Long, Cong; Wang, Guoxiang; Gao, Yun; Liu, Junhua; Jiao, Binghua

    2011-01-01

    East China Sea is one of the four sea areas in China, which possesses peculiar ecological environment and many kinds of living creatures, especially the microorganisms. We established the East China Sea microorganism library (during 2006-2010) for the first time, which stored about 30000 strains that covered most kinds of the species. In this paper, 395 pure strains of East China Sea microorganism library which belong to 33 different genera were mainly introduced. Sulfitobacter, Halomonas, Bacillus, Pseudoalteromonas, and Idiomarina were the most dominant species. On the large-scale biological activity screening of the 395 strains, 100 strains possess different biological activities based on different screening models, of which 11.4% strains have antibacterial activities, 15.9% have cytotoxicity activities, and 6.1% have antioxidation activities. Besides, the secondary metabolites of 6 strains with strong biological activities were studied systematically; diketopiperazines and macrocyclic lactones are the active secondary metabolites. The species and the biological activity of microorganisms diversity, the abundant structure type of the secondary metabolites, and their bioactivities all indicate that East China Sea is a potent marine microorganisms-derived developing resource for drug discovery.

  20. Changes in nematode communities in different physiographic sites of the condor seamount (north-East atlantic ocean) and adjacent sediments.

    PubMed

    Zeppilli, Daniela; Bongiorni, Lucia; Serrão Santos, Ricardo; Vanreusel, Ann

    2014-01-01

    Several seamounts are known as 'oases' of high abundances and biomass and hotspots of biodiversity in contrast to the surrounding deep-sea environments. Recent studies have indicated that each single seamount can exhibit a high intricate habitat turnover. Information on alpha and beta diversity of single seamount is needed in order to fully understand seamounts contribution to regional and global biodiversity. However, while most of the seamount research has been focused on summits, studies considering the whole seamount structure are still rather poor. In the present study we analysed abundance, biomass and diversity of nematodes collected in distinct physiographic sites and surrounding sediments of the Condor Seamount (Azores, North-East Atlantic Ocean). Our study revealed higher nematode biomass in the seamount bases and values 10 times higher in the Condor sediments than in the far-field site. Although biodiversity indices did not showed significant differences comparing seamount sites and far-field sites, significant differences were observed in term of nematode composition. The Condor summit harboured a completely different nematode community when compared to the other seamount sites, with a high number of exclusive species and important differences in term of nematode trophic diversity. The oceanographic conditions observed around the Condor Seamount and the associated sediment mixing, together with the high quality of food resources available in seamount base could explain the observed patterns. Our results support the hypothesis that seamounts maintain high biodiversity through heightened beta diversity and showed that not only summits but also seamount bases can support rich benthic community in terms of standing stocks and diversity. Furthermore functional diversity of nematodes strongly depends on environmental conditions link to the local setting and seamount structure. This finding should be considered in future studies on seamounts, especially in

  1. Changes in Nematode Communities in Different Physiographic Sites of the Condor Seamount (North-East Atlantic Ocean) and Adjacent Sediments

    PubMed Central

    Zeppilli, Daniela; Bongiorni, Lucia; Serrão Santos, Ricardo; Vanreusel, Ann

    2014-01-01

    Several seamounts are known as ‘oases’ of high abundances and biomass and hotspots of biodiversity in contrast to the surrounding deep-sea environments. Recent studies have indicated that each single seamount can exhibit a high intricate habitat turnover. Information on alpha and beta diversity of single seamount is needed in order to fully understand seamounts contribution to regional and global biodiversity. However, while most of the seamount research has been focused on summits, studies considering the whole seamount structure are still rather poor. In the present study we analysed abundance, biomass and diversity of nematodes collected in distinct physiographic sites and surrounding sediments of the Condor Seamount (Azores, North-East Atlantic Ocean). Our study revealed higher nematode biomass in the seamount bases and values 10 times higher in the Condor sediments than in the far-field site. Although biodiversity indices did not showed significant differences comparing seamount sites and far-field sites, significant differences were observed in term of nematode composition. The Condor summit harboured a completely different nematode community when compared to the other seamount sites, with a high number of exclusive species and important differences in term of nematode trophic diversity. The oceanographic conditions observed around the Condor Seamount and the associated sediment mixing, together with the high quality of food resources available in seamount base could explain the observed patterns. Our results support the hypothesis that seamounts maintain high biodiversity through heightened beta diversity and showed that not only summits but also seamount bases can support rich benthic community in terms of standing stocks and diversity. Furthermore functional diversity of nematodes strongly depends on environmental conditions link to the local setting and seamount structure. This finding should be considered in future studies on seamounts, especially in

  2. Nutrient dynamics from the Changjiang (Yangtze River) estuary to the East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, Su Mei; Qi, Xiao Hong; Li, Xiaona; Ye, Hao Ran; Wu, Ying; Ren, Jing Ling; Zhang, Jing; Xu, Wei Yi

    2016-02-01

    Water and sediment samples were collected from the Changjiang (Yangtze River) estuary and the adjacent East China Sea during impoundment of the river at the Three Gorges Dam. The concentrations of dissolved inorganic and organic nutrients, and particulate inorganic phosphorus and particulate organic phosphorus in the water column (PIP and POP, respectively) and sediments (SIP and SOP, respectively) were analyzed. The nutrient dynamics in salt marshes associated with the Changjiang estuary were also considered. In addition, river water samples were collected bimonthly in the lower reaches of the Changjiang. The concentrations of dissolved inorganic nutrients, PIP and POP showed temporal and spatial variations, which decreased from the coast to offshore areas. The dissolved organic nitrogen and phosphorus (P) concentrations showed patchy distributions, but were consistent with the distribution of phytoplankton biomass. Phosphorus is the major limiting element for phytoplankton growth. Among the various P forms, particulate P represented 38-52% of total P. The PIP and POP concentrations showed clear seasonal variations corresponding to the occurrence of the levels of suspended particulate matter. The P accumulation rates showed a decreasing trend from the coast to offshore areas, and high P burial efficiencies were found; the latter were related to a low benthic PO43 - flux and high sediment accumulation rates. The potential bioavailable P was estimated to be 65-70% of total P, of which more than two-thirds was regenerated in the water column. The salt marsh in the Changjiang estuary plays an important ecological role in nutrient transport from the river to offshore areas, and increased P limitation.

  3. Impact of East Asian Summer Monsoon on the Air Quality over China: View from space

    SciTech Connect

    Zhao, Chun; Wang, Yuhang; Yang, Qing; Fu, Rong; Cunnold, Derek; Choi, Yunsoo

    2010-05-04

    Tropospheric O3 columns retrieved from OMI and MLS measurements, CO columns from MOPITT, and tropospheric O3 and CO concentrations from TES from May to August in 2006 are analyzed using the Regional chEmical and trAnsport Model (REAM) to investigate the impact of the East Asian summer monsoon on the air quality over China. The observed and simulated migrations of O3 and CO are in good agreement, demonstrating that the summer monsoon significantly affects the air quality over southeastern China and this influence extends to central East China from June to July. Enhancements of CO and O3 over southeastern China disappear after the onset of the summer monsoon and re-emerge in August after the monsoon wanes. The pre-monsoon high O3 concentrations over southern China are due to photochemical production from pollutant emissions and the O3 transport from the stratosphere. In the summer monsoon season, the O3 concentrations are relatively low over monsoon-affected regions because of the transport of marine air masses and weak photochemical activity. We find that the monsoon system strongly modulates the pollution problem over a large portion of East China in summer, depending on its strength and tempo-spatial extension. Model results also suggest that transport from the stratosphere and long-range transport from East China and South/Central Asia all make significant contributions to O3 enhancements over West China. Satellite observations provide valuable information for investigating the monsoon impact on air quality, particularly for the regions with limited in situ measurements.

  4. East-China Geochemistry Database (ECGD):A New Networking Database for North China Craton

    NASA Astrophysics Data System (ADS)

    Wang, X.; Ma, W.

    2010-12-01

    North China Craton is one of the best natural laboratories that research some Earth Dynamic questions[1]. Scientists made much progress in research on this area, and got vast geochemistry data, which are essential for answering many fundamental questions about the age, composition, structure, and evolution of the East China area. But the geochemical data have long been accessible only through the scientific literature and theses where they have been widely dispersed, making it difficult for the broad Geosciences community to find, access and efficiently use the full range of available data[2]. How to effectively store, manage, share and reuse the existing geochemical data in the North China Craton area? East-China Geochemistry Database(ECGD) is a networking geochemical scientific database system that has been designed based on WebGIS and relational database for the structured storage and retrieval of geochemical data and geological map information. It is integrated the functions of data retrieval, spatial visualization and online analysis. ECGD focus on three areas: 1.Storage and retrieval of geochemical data and geological map information. Research on the characters of geochemical data, including its composing and connecting of each other, we designed a relational database, which based on geochemical relational data model, to store a variety of geological sample information such as sampling locality, age, sample characteristics, reference, major elements, rare earth elements, trace elements and isotope system et al. And a web-based user-friendly interface is provided for constructing queries. 2.Data view. ECGD is committed to online data visualization by different ways, especially to view data in digital map with dynamic way. Because ECGD was integrated WebGIS technology, the query results can be mapped on digital map, which can be zoomed, translation and dot selection. Besides of view and output query results data by html, txt or xls formats, researchers also can

  5. From Source to Sink of Polycyclic Aromatic Hydrocarbons in Sediments in the East China Seas

    NASA Astrophysics Data System (ADS)

    Guo, Z.; Lin, T.; Hu, L.

    2014-12-01

    The East China Seas (ECSs), including Bohai Sea (77,000 km2), Yellow Sea (400,000 km2) and East China Sea (770,000 km2) have experienced a great variety of demographic and economic conditions which have a profound influence on the source composition of land-based polycyclic aromatic hydrocarbons (PAHs) in the sediments since ECSs's coasts support about 420 million peoples, provide more than half of the national GDP in China in 2007, and are major emission regions of PAHs in China. Furthermore, the ECSs are downwind of the Asian continental outflow in spring and winter driven by the East Asian monsoon. The sources of 16 USEPA priority PAHs in strategically selected surface sediment samples from the ECSs were apportioned using positive matrix factorization model, and the input pathways of PAHs were also revealed in the regions. Four sources were identified: petroleum residue, vehicular emissions, coal combustion and biomass burning. Petroleum residue was the dominant contributor of PAHs in the coast of the Bohai Bay probably due to Haihe River runoff, oil leakage from ships and offshore oil fields. The PAHs in sediments of the coastal East China Sea were mainly sourced from the Yangtze River discharge into the sea. The combined results of PMF, PCA and composition of PAHs suggest that the atmospheric deposition is the dominate input of PAHs for the open seas of Bohai Sea, East China Sea and Yellow Sea; while river input is the major pathway of PAHs in the estuarine and neighborhood coastal areas. The demographic and economic conditions around the ECSs have profound influence on the origins of the land-based PAHs in the sediments of the open seas.

  6. Spatial distributions of floating seaweeds in the East China Sea from late winter to early spring.

    PubMed

    Mizuno, S; Ajisaka, T; Lahbib, S; Kokubu, Y; Alabsi, M N; Komatsu, T

    2014-01-01

    Floating seaweeds play an important role as a habitat for many animals accompanying or attaching to them in offshore waters. It was in 2000 that the first report described abundant distributions of floating seaweeds in offshore waters in the East China Sea in spring. Young individuals of the yellowtail Seriola quinqueradiata are captured for aquaculture purposes from floating seaweeds in the East China Sea. Therefore, a sound understanding of the distributions of floating seaweeds in the East China Sea is needed. Detailed information is especially important during the late winter to early spring, which corresponds to the juvenile period of the yellowtail. Thus, field surveys using R/V Tansei-Maru were conducted in the Japanese Exclusive Economic Zone in the East China Sea from late winter to early spring in 2010 and 2011. We obtained positions of the vessel by GPS and transversal distances from the vessel to a raft by visual observation. Distance sampling method (Thomas et al. 2010) was applied to estimation of floating seaweed densities (rafts km(-2)). Seaweed rafts were also randomly sampled using nets during the research cruises. In the East China Sea, seaweed rafts were distributed mainly on the continental shelf west of the Kuroshio, especially in waters between 26° N and 30° N. Collected rafts consisted of only one species, Sargassum horneri (Turner) C. Agardh. Taking into account surface currents and geographical distribution of S. horneri, it is estimated that these floating seaweeds originated from natural beds along the coast between mid and south China. Considering the approximate travel times, it is suggested that floating patches are colonized by yellowtails early on during their trips, i.e., close to the Chinese coast.

  7. Origin of allanite in gneiss and granite in the Dabie orogenic belt, Central East China

    NASA Astrophysics Data System (ADS)

    Guo, Haihao; Xiao, Yilin; Xu, Lijuan; Sun, He; Huang, Jian; Hou, Zhenhui

    2017-03-01

    Allanite is a common accessory mineral phase, representing an important carrier of rare earth elements, Th, U, Sr and other trace elements in most continental rocks. As Th and U can be incorporated into the allanite lattice, the mineral is a good geochronological tool for constraining geological events. Moreover, the trace element features δEu, Th/U ratio and common lead content of allanite are indicators of the forming conditions. Allanite and coexisting epidote-group minerals are abundant in ultrahigh-pressure (UHP) metamorphic rocks from the Dabie-Sulu orogen in central East China. However, if these minerals formed in the Neoproterozoic as magmatic phases, or in the Triassic as metamorphic phases is a matter of long-standing controversy. We report major and trace element analyses of whole rocks, allanite and coexisting epidote-group minerals, together with U-Th-Pb isotopic compositions of allanite in UHP gneiss from the Dabie-Sulu orogen, and allanite in the adjacent Jingshan granite. The granite is emplaced along the southeastern margin of the North China Craton and considered a product of partial melting of the subducted Dabie-Sulu gneiss. Trace elements (low Th/U and La/Sm, high δEu and high Sr) and high common lead concentrations indicate a metamorphic origin of allanite-epidote in the UHP gneiss. On the other hand, coarse-grained allanite from the Jingshan granite shows a corrosion core and a magmatic rim with common 208Pb up to 70% in the core and less than 30% in the rim. The allanite cores are of peritectic and the rims of magmatic origin with ages of ∼160 Ma, consistent with the granite crystallization age. In combination with previous studies, we conclude that the allanite of the Jingshan granite has form from the subducted and remolten Dabie-Sulu gneiss. Allanite records Triassic UHP metamorphic ages as well as Jurassic peritectic-magmatic ages as a part of the evolution of the Dabie-Sulu orogen.

  8. Distribution of nanoflagellates in five water masses of the East China Sea in autumn and winter

    NASA Astrophysics Data System (ADS)

    Lin, Shiquan; Huang, Lingfeng; Zhu, Zhisheng; Xiong, Yuan; Lu, Jiachang

    2016-02-01

    The variations of abundance, biomass and trophic structure of nanoflagellates (NF) among five typical water masses in the East China Sea were investigated in autumn (November 19-December 23, 2006) and winter (February 22-March 11, 2007). It was found that water mass had a significant impact on the distribution of NF. Either in autumn or in winter, the highest abundance and biomass of NF were recorded in the East China Sea Shelf Mixing Water (ECSSMW), and the lowest in the Kuroshio Subsurface Water (KSSW). While in the East China Sea Coastal Water (ECSCW), the abundance and biomass of both heterotrophic nanoflagellates (HNF) and pigmented phototrophic nanoflagellates (PNF) were only slightly higher than that in Taiwan Strait Water (TSW) and Kuroshio Surface Water (KSW). In respect to the seasonal variation, the abundance and biomass of NF in TSW declined in winter, while in other 4 water masses, they showed an increasing trend from autumn to winter, mainly due to the decrease (in TSW) or increase (in ECSCW, ECSSMW, KSW and KSSW) of HNF. The distribution pattern of abundance- or biomass-based PNF/HNF ratio was found to be correlated to the nutrient level of the water mass. Results of Pearson correlation analysis and principle component analysis indicated that PNF was mainly constrained by nutrient supply, and HNF was controlled by food availability in the East China Sea.

  9. History Didactics in the Post Cold War World: Central Asia, the Middle East, and China.

    ERIC Educational Resources Information Center

    Forsyth, Louise; Gould, David; Lawrence, David

    2000-01-01

    Examines three key geographical regions, Central Asia, the Middle East, and China, discussing how the political changes resulting from the end of the Cold War have affected each area. Attempts to demonstrate how teachers can address these changes in their classrooms. (CMK)

  10. The Development of the Distance Education College of East China Normal University: A Case Study

    ERIC Educational Resources Information Center

    Ye, Lixin; Su, Xiaobing; Yan, Hanbing

    2009-01-01

    Purpose: This paper aims to present a picture of the past and the present status of the Distance Education College (DEC) of East China Normal University (ECNU). It describes what the DEC has achieved in each phase, and probes into some essential problems that the DEC has attempted to solve. Design/methodology/approach: This article provides a…

  11. Ship measurements of submicron aerosol size distributions over the Yellow Sea and the East China Sea

    NASA Astrophysics Data System (ADS)

    Kim, Jong Hwan; Yum, Seong Soo; Lee, Young-Gon; Choi, Byoung-Cheol

    2009-08-01

    During the spring of 2005, the total particle concentrations and the submicron aerosol size distributions were measured on board the research vessel over the south sea of Korea and the Korean sector of the Yellow Sea. Similar measurements were made over the East China Sea in autumn 2005. The aerosol properties varied dynamically according to the meteorological conditions, the proximity to the land masses and the air mass back trajectories. The average total particle concentration was the lowest over the East China Sea, 4335 ± 2736 cm - 3, but the instantaneous minimum, 837 cm - 3, for the entire ship measurement was recorded during the Yellow Sea cruise. There was also a long (more than 6 h) stretch of low total particle concentrations that fell as low as 1025 cm - 3 during the East China Sea cruise when the ship was the farthest from the shores and the air mass back trajectories resided long hours over the sea. These observations lead to the suggestion of ~ 1000 cm - 3 as the background total particle concentration over the marine boundary layer in the studied region of the Yellow Sea and the East China Sea, implying significant anthropogenic influence even for the background value. In the mean time, average aerosol size distributions were unimodal and the mode diameter ranged between 52 and 86 nm, excluding the fog periods, which suggests that the aerosols measured in this study experienced relatively less aging processes within the marine boundary layer.

  12. A Review of HRD Research in Three Areas of East Asia: Mainland China, Taiwan, and Japan

    ERIC Educational Resources Information Center

    Lee, Yi-Hsuan; Lin, Jie; Paprock, Kenneth E.; Lynham, Susan A.; Li, Jie

    2004-01-01

    Recent research focusing on Human Resource Development (HRD) in East Asia is attracting increasing attention. The purpose of the study is to explore the definition and practice of HRD, together with influencing cultural factors, in Mainland China, Taiwan, and Japan. The results indicate a difference in the definition and implementation of HRD…

  13. Time trends of polybrominated diphenyl ethers in East China Seas: Response to the booming of PBDE pollution industry in China.

    PubMed

    Li, Yuanyuan; Lin, Tian; Hu, Limin; Feng, Jialiang; Guo, Zhigang

    2016-01-01

    The East China Seas (ECSs) are the receptors of the land-based persistent organic pollutants (POPs), such as polybrominated diphenyl ethers (PBDEs) mainly from China through atmospheric deposition driven by the East Asian winter monsoon and fluvial discharge (e.g., Yangtze River and Yellow River), making the offshore sediments to be a good proxy to reconstruct history of those pollutants in China. In this work, four well-placed sediment cores were extracted from the mud areas in the ECSs, and the (210)Pb-dated cores were analyzed to yield historical concentration profiles of PBDEs in the area. The results showed that there was a persistent increase from 1970s and almost no clear sign in the decline of PBDEs until recently in China. More importantly, there was a faster increase of PBDEs from 1990s in China; while this period was just shown as gradually leveling off or even declining trends in developed countries. The persistently increasing trend of PBDEs in China since 1990s could be largely due to the booming of the manufacturing industry and unexpectedly transfer of PBDE pollution from developed countries to China. Besides, the relative high concentrations and fluxes of PBDEs in the core from coastal ECS located near a well-known electrical/electronic waste (e-waste) recycling area suggests an important contribution of PBDE emissions from recycling centers of e-waste in China. Although efforts in environmental monitoring of PBDE contamination have been substantially increased over the last decade, China is still lagging behind in terms of nationwide regulation of PBDE usage and treatment of disposal PBDE-containing products.

  14. The influence of dry lakebeds, degraded sandy grasslands and abandoned farmland in the arid inlands of northern China on the grain size distribution of East Asian aeolian dust

    NASA Astrophysics Data System (ADS)

    Yang, Li-Rong; Yue, Le-Ping; Li, Zhi-Pei

    2008-02-01

    Dry lakes, degraded sandy grasslands, abandoned farmland and mobile dunes which are widely distributed throughout the arid areas of northern China have been investigated in this work. Gain-size distribution of the surface sediments of Manas lake in Junggar basin, Juyan lake in the Alxa plateau, Zhuye lake in Minqin basin and most deserts (such as Mu Us desert, Otindag desert, Horqin desert and Hulun Buir desert) in China have been analyzed. The results show clay with particle sized <10 μm on the surface sediments of dry lakebed and sandy grassland developed from dry lakebed, respectively, account for >60% and ˜50% of the total mass. Since the tiny particles on the surface of abandoned farmland are blown away easily and rapidly, the content of clay particles in Minqin basin is <14%. The grain-size distribution of mobile dunes in northern China mainly consists of particles >63 μm and few particles <10 μm. Consequently, although sand/dust storms originate primarily in the western deserts, the gobi areas of the Alxa plateau, the north and east of Hexi Corridor and in central Mongolia, the widely distributed dry lakebeds, sandy grasslands and abandoned farmland adjacent to the deserts also contribute to aeolian dusts. Hence, the material sources for sand dust storm in East Asia include inland deserts, but also dry lakes, sandy grasslands and abandoned farmland, which are widely distributed throughout the arid inlands of northern China.

  15. Assessment of the Impact of The East Asian Summer Monsoon on the Air Quality Over China

    NASA Astrophysics Data System (ADS)

    Hao, Nan; Ding, Aijun; Safieddine, Sarah; Valks, Pieter; Clerbaux, Cathy; Trautmann, Thomas

    2016-04-01

    Air pollution is one of the most important environmental problems in developing Asian countries like China. In this region, studies showed that the East Asian monsoon plays a significant role in characterizing the temporal variation and spatial patterns of air pollution, since monsoon is a major atmospheric system affecting air mass transport, convection, and precipitation. Knowledge gaps still exist in the understanding of Asian monsoon impact on the air quality in China under the background of global climate change. For the first time satellite observations of tropospheric ozone and its precursors will be integrated with the ground-based, aircraft measurements of air pollutants and model simulations to study the impact of the East Asian monsoon on air quality in China. We apply multi-platform satellite observations by the GOME-2, IASI, and MOPITT instruments to analyze tropospheric ozone and CO, precursors of ozone (NO2, HCHO and CHOCHO) and other related trace gases over China. Two years measurements of air pollutants including NO2, HONO, SO2, HCHO and CHOCHO at a regional back-ground site in the western part of the Yangtze River Delta (YRD) in eastern China will be presented. The potential of using the current generation of satellite instruments, ground-based instruments and aircraft to monitor air quality changes caused by the East Asian monsoon circulation will be presented. Preliminary comparison results between satellite measurement and limited but valuable ground-based and aircraft measurements will also be showed.

  16. The influence of mariculture on mercury distribution in sediments and fish around Hong Kong and adjacent mainland China waters.

    PubMed

    Liang, Peng; Shao, Ding-Ding; Wu, Sheng-Chun; Shi, Jian-Bo; Sun, Xiao-lin; Wu, Fu-Yong; Lo, S C L; Wang, Wen-Xiong; Wong, Ming H

    2011-02-01

    To study the influence of mariculture on mercury (Hg) speciation and distribution in sediments and cultured fish around Hong Kong and adjacent mainland China waters, sediment samples were collected from six mariculture sites and the corresponding reference sites, 200-300 m away from the mariculture sites. Mariculture activities increased total mercury, organic matter, carbon, nitrogen and sulfur concentrations in the surface sediments underneath mariculture sites, possibly due to the accumulation of unconsumed fish feed and fish excretion. However, methylmercury (MeHg) concentrations and the ratio of MeHg to THg (% MeHg) in sediments underneath mariculture sites were lower than the corresponding reference sites. The % MeHg in sediments was negatively correlated (r = -0.579, p < 0.05) with organic matter (OM) content among all sites, indicating that OM may have inhibited Hg methylation in surface sediments. Three mariculture fish species were collected from each mariculture site, including red snapper (Lutjanus campechanus), orange-spotted grouper (Epinephelus coioides) and snubnose pompano (Trachinotus blochii). The average MeHg concentration in fish muscle was 75 μg kg⁻¹ (wet weight), and the dietary intake of MeHg through fish consumption for Hong Kong residents was 0.37 μg kg⁻¹ week⁻¹, which was lower than the corresponding WHO limits (500 μg kg⁻¹ and 1.6 μg kg⁻¹ week⁻¹).

  17. Aquaculture-derived enrichment of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in coastal sediments of Hong Kong and adjacent mainland China.

    PubMed

    Wang, Hong-Sheng; Chen, Zhuo-Jia; Cheng, Zhang; Du, Jun; Man, Yu-Bon; Leung, Ho-Man; Giesy, John P; Wong, Chris K C; Wong, Ming-Hung

    2014-01-01

    To evaluate contamination of sediments along the coast of Hong Kong and adjacent mainland China, concentrations of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in surface and core sediments were measured in six mariculture zones. In surface sediments (0 to 5 cm), concentrations of ∑HCHs and ∑DDTs in mariculture sediments were approximately 1.3- and 7.7-fold greater, respectively, than those detected in sediments at corresponding reference sites, which were 1 to 2 km away in areas where there was no mariculture. Similarly, in cores of sediments, concentrations of ∑HCHs and ∑DDTs were 1.2- and 14-fold greater in mariculture zones, respectively. Enrichment relative to regional background concentrations, expressed as percentages was as large as 8.67 × 10(3)% for o,p'-DDD. The major sources of the enriched organochlorine pesticides (OCPs) were hypothesized to be derived from the use of contaminated fish feeds and anti-fouling paints for maintaining fish cages. Results of ecological risk assessments revealed that enriched OCPs had a large potential to contaminate the surrounding marine environment and lead to adverse effects on the associated biota. To our knowledge, this is the first study to evaluate the differences of OCP contaminations between mariculture and natural coastal sediments.

  18. Carbonyl sulfide and dimethyl sulfide fluxes in an urban lawn and adjacent bare soil in Guangzhou, China.

    PubMed

    Yi, Zhigang; Wang, Xinming

    2011-01-01

    Carbonyl sulfide (COS) and dimethyl sulfide (DMS) fluxes from an urban Cynodon dactylon lawn and adjacent bare soil were measured during April-July 2005 in Guangzhou, China. Both the lawn and bare soil acted as sinks for COS and sources for DMS. The mean fluxes of COS and DMS in the lawn (-19.27 and 18.16 pmol/(m2 sec), respectively) were significantly higher than those in the bare soil (-9.89 and 9.35 pmol/(m2 sec), respectively). Fluxes of COS and DMS in mowed lawn were also higher than those in bare soils. Both COS and DMS fluxes showed diurnal variation with detectable but much lower values in the nighttime than in the daytime. COS fluxes were related significantly to temperature and the optimal temperature for COS uptake was 29 degrees C. While positive linear correlations were found between DMS fluxes and temperature. COS fluxes increased linearly with ambient COS mixing ratios, and had a compensation point of 336 ppt.

  19. East China Sea δ18O Record Detects Millennial-Scale Changes in the East Asian Summer Monsoon

    NASA Astrophysics Data System (ADS)

    Gleeman, E.; Clemens, S. C.; Lawman, A. E.; Kubota, Y.; Holbourn, A. E.; Martin, A.

    2015-12-01

    The East Asian Summer Monsoon (EASM) brings heavy summer rainfall to some of Asia's most densely-populated areas, impacting agricultural production and water resources. Sediment cores were recovered from International Ocean Drilling Program Site U1429 in the East China Sea (31° 37.04' N, 128° 59.50' E, 732 mbsl). This location receives runoff from the Yangtze River, which serves as a major drainage system for monsoon-induced precipitation. Hence, the δ18O record of planktonic foraminifera at Site U1429 reflects changes in regional, monsoon-driven salinity. The top 100 meters of core at Site U1429 were sampled at a preliminary resolution of 15 cm and processed to isolate the planktonic foraminifer Globigerinoides ruber for δ18O mass spectrometry analyses. Abrupt, millennial-scale regional climate variability in the EASM and its linkage to orbital forcings have been reconstructed using stratigraphic analysis of δ18O. The sub-orbital scale structure of the δ18O record over the past 400 kyr matches the structures of both the composite speleothem δ18O from eastern China (Sanbao and Hulu caves) and the planktonic δ18O record from northern South China Sea Site 1146. The similarities between these δ18O records indicate a strong regional response to monsoon forcing. Removal of the temperature component of the δ18O signal by using Mg/Ca (G. ruber) paleothermometry will provide a record of changes in the δ18O composition of seawater in response to Yangtze River runoff.

  20. Looking East: A Rare Glimpse at Theatre Education in China.

    ERIC Educational Resources Information Center

    Leptak-Moreau, Jeffrey

    1997-01-01

    Recounts how a delegation of 23 American theater educators took a two-week tour of Chinese theater companies and schools. Finds that although all theater takes years of training in China, there is little performance by youngsters; and that few professional companies have audience development activities or school performances. Describes traditional…

  1. Observation-based Understanding of the Cloud Properties over East China Region

    NASA Astrophysics Data System (ADS)

    Zhao, C.

    2015-12-01

    Cloud properties over East China are described based on observations from satellite (MODIS), ground site and aircraft. Based on satellite observations, 10-year averaged cloud fraction over the whole China region is around 66%, similar to the average value of global, with the largest cloud occurrence in Summer; the cloud fraction increases slightly during last 10 years; more clouds are found at southeast region than at northwest region; cloud droplet effective radius shows the smallest values around 10 um at mid-latitude regions and largest values at high latitude regions; further PDF analysis shows that cloud droplet effective radius demonstrates a bimodal distribution with maximum occurrences around 10-16 um. Ground site observations show that cloud fraction at Taihu site is around 65% for 2013, consistent with that found by MODIS at the closest grid to the site; more clouds are found at night than during day. In-situ aircraft observations over Huanghua city show that cloud droplet effective radius increases with height, with values from 3-5 um at low altitude, 7-9 um at mid altitude, to 10-13 um at high altitude. While the aircraft observation sample volume is limited, the in-situ observed cloud properties demonstrate that cloud droplet re increases with height, consistent with many findings by in-situ aircraft at other locations. The consistency of satellite observed cloud droplet re between East China and other regions is likely caused by the fact that the cloud properties observed by satellite is more representative of those clouds at high altitudes which are weakly affected by the aerosols within the boundary layers. On the other hand, the cloud droplet re at the cloud bases over East China is much smaller than those found at other locations, likely demonstrating the significant impacts by the heavy aerosol loadings at this region. Further studies with more site and aircraft observations over East China are needed.

  2. Magnetic mineral diagenesis in the river-dominated inner shelf of the East China Sea, China

    NASA Astrophysics Data System (ADS)

    Ge, Can; Zhang, Weiguo; Dong, Chenyin; Dong, Yan; Bai, Xuexin; Liu, Jinyan; Hien, Nguyen Thi Thu; Feng, Huan; Yu, Lizhong

    2015-07-01

    The inner shelf of the East China Sea is a river-dominated margin characterized by fine-grained mud deposits and a rapid sedimentation rate. Three short sediment cores (~2.7 m in length) were examined to characterize spatial variations in magnetic mineral diagenesis. The sediment cores were analyzed for sedimentation rates, magnetic properties, particle size distribution, organic carbon, and total sulfur content. The two more proximal cores with higher sedimentation rates (~2.2 cm/yr and ~0.96 cm/yr) do not exhibit obvious effects of reductive dissolution of magnetite with increasing depth, which is consistent with their lower total sulfur content. The offshore core, A12-4, which has a lower sedimentation rate, contains clear evidence of magnetite dissolution and increasing total sulfur content with depth. The three cores have a similar sediment source and organic matter input; therefore, we suggest that a higher sedimentation rate will lead to less reductive diagenesis of magnetite, assuming that other factors are constant. The iron- to sulfate-reduction boundary, i.e., revealed by the onset of a rapid decline of magnetic susceptibility, is located 1.0 m below seafloor in core A12-4. This is much deeper than is reported in many other coastal marine environments and can be explained by the higher sedimentation rate, the presence of refractory terrestrial organic matter, and an abundant input of detrital iron oxides. This study demonstrates that analyses of the magnetic mineral zonation provide a straightforward approach to assess diagenetic organic carbon decomposition pathways in marine environments.

  3. [Genetic variation at the pantophysin (PanI) locus in North-East Arctic cod Gadus morhua L. (Gadiformes: Gadidae) population in the Barents Sea and adjacent waters].

    PubMed

    Makeenko, G A; Volkov, A A; Mugue, N S; Zelenina, D A

    2014-12-01

    We investigated polymorphisms in the pantophysin gene (Pan I locus) in a population of North-East Arctic cod, Gadus morhua L., throughout its foraging area in the Barents Sea and adjacent waters. Correlations between the frequencies of Pan I alleles and habitat conditions, such as depth and temperature, were explored. This study was based on a large number of specimens (2210 individuals) of different age and wide geographic sampling coverage. The frequency of the Pan I(A) allele, a known genetic marker of coastal cod, varied from zero to 0.47. Allele frequencies correlated with depth at the sampling location but not with bottom water temperatures. We observed variations in Pan I(A) frequencies among different age cohorts from the same area. The most prominent shift in Pan I polymorphism was detected at the early stages of the fish life cycle, between pelagic juveniles and benthic cod. We found that the Pan I(A) allele frequency in pelagic yearling cod was essentially same throughout the studied areas in the Barents Sea. In turn, juveniles settling at the northern and deep water locations showed a significant decrease in the allele frequency. In contrast, the frequency of the Pan I(A) allele remained constant in juveniles settling in shallow waters when compared to the pelagic stage. These results confirm the selective nature of the cod Pan I locus and indicate that selection process acting on individuals with different genotypes at the Pan I locus leads to the formation of a stable spatial distribution of allele frequencies observed in adult cod.

  4. Historic climate variability of wetness in East China (960-1992): a wavelet analysis

    NASA Astrophysics Data System (ADS)

    Jiang, Jianmin; Zhang, Deer; Fraedrich, Klaus

    1997-07-01

    Temporal and spatial climate variability in East China is analysed for the last 1033 years (AD 960-1992) based on historic annual grades of wetness for six regions in East China. This data set is subjected to a Mexican hat wavelet transform for displaying variations of different frequencies at particular time points, persistent anomalies, and abrupt changes between them. The following results are noted: the persistent dry stage 1120-1220 and wet stage 1280-1390 in the coastal regions are the outstanding features during the last 1033 years. For all regions an almost synchronous change occurs around 1890 from a weaker wet phase to a weaker dry phase; climatic variations on longer time-scales cover larger areas. On shorter time-scales, synchronous fluctuations are observed in fewer years than longer time-scale variability.

  5. Variations of picoplankton abundances during blooms in the East China Sea

    NASA Astrophysics Data System (ADS)

    Zhao, Yuan; Zhao, Li; Zhang, Wuchang; Sun, Jun; Huang, Lingfeng; Li, Jia; Zhai, Hongchang; Liu, Sumei; Xiao, Tian

    2016-02-01

    The picoplankton distribution in the East China Sea was investigated during bloom events occurred in spring (June) and summer (August) 2011. In spring, there was no significant difference in picoplankton abundances between areas where bloom conditions were or were not established. In the bloom area, Synechococcus, picoeukaryotes and heterotrophic prokaryotes exhibited at only some stations that abundances were higher than those within the non-bloom area. In summer, the abundances of Synechococcus and picoeukaryotes were significantly higher inside the bloom area than outside. Among the picoplankton components, heterotrophic prokaryotes represented the highest carbon biomass. Factors that most influenced picoplankton distribution under bloom conditions in the East China Sea varied with season. In spring, ciliates and salinity tended to be the main factors, whereas in summer, this role was played by temperature and chlorophyll a concentration.

  6. Characteristics of Thermal Finestructure in the Southern Yellow Sea and the East China Sea from Airborne Expendable Bathythermograph Measurements

    DTIC Science & Technology

    2008-01-01

    J. Oceanic Eng., 29, 1054–1060. 17 Zodiatis, G., and G. P. Gasparini (1996): Thermohaline staircase formations in the 18 Tyrrhenian Sea . Deep- Sea ...1 1 2 Characteristics of Thermal Finestructure in the Southern 3 Yellow Sea and the East China Sea from Airborne 4 Expendable...CA93943-5001, USA Tel: 1-831-656-7819 Fax: 1-831-656-3686 Email: spark@nps.edu Key words: Yellow/East China Seas , AXBT, synoptic thermal fronts

  7. CNA Maritime Asia Project. Workshop One: The Yellow and East China Seas

    DTIC Science & Technology

    2012-05-01

    the concomitant conflicts among all three par- ties over disputed fishing grounds. About 600 million people live in the Yellow Sea catchment area , and...concerns in East Asia have increasing- ly revolved around problems in the maritime domain, the Center for Naval Analyses has elected to make mar- itime...essentially home waters for the navies of China, Japan, and both Koreas. As a result, it is a “lo- cal” training area for four—or, if one includes

  8. A Study of Mobile Trough Genesis Over The Yellow Sea-East China Sea Region

    DTIC Science & Technology

    2011-07-21

    Mongolian Plateau. The maximum that extends over the Yellow Sea and East China Sea is the only region of enhanced mobile trough formation which is...Gammon used PTD to further investigate mobile troughs and extratropical cyclones. An investigation of mobile trough formation over the Mongolian Plateau...over the Mongolian plateau. The results from the previous studies provide a measure of confidence for this research. Two case studies were chosen using

  9. Evidence of a Cooler Continental Climate in East China during the Warm Early Cenozoic

    PubMed Central

    Zhang, Qian-Qian; Smith, Thierry; Yang, Jian; Li, Cheng-Sen

    2016-01-01

    The early Cenozoic was characterized by a very warm climate especially during the Early Eocene. To understand climatic changes in eastern Asia, we reconstructed the Early Eocene vegetation and climate based on palynological data of a borehole from Wutu coal mine, East China and evaluated the climatic differences between eastern Asia and Central Europe. The Wutu palynological assemblages indicated a warm temperate vegetation succession comprising mixed needle- and broad-leaved forests. Three periods of vegetation succession over time were recognized. The changes of palynomorph relative abundance indicated that period 1 was warm and humid, period 2 was relatively warmer and wetter, and period 3 was cooler and drier again. The climatic parameters estimated by the coexistence approach (CA) suggested that the Early Eocene climate in Wutu was warmer and wetter. Mean annual temperature (MAT) was approximately 16°C and mean annual precipitation (MAP) was 800–1400 mm. Comparison of the Early Eocene climatic parameters of Wutu with those of 39 other fossil floras of different age in East China, reveals that 1) the climate became gradually cooler during the last 65 million years, with MAT dropping by 9.3°C. This cooling trend coincided with the ocean temperature changes but with weaker amplitude; 2) the Early Eocene climate was cooler in East China than in Central Europe; 3) the cooling trend in East China (MAT dropped by 6.9°C) was gentler than in Central Europe (MAT dropped by 13°C) during the last 45 million years. PMID:27196048

  10. Evidence of a Cooler Continental Climate in East China during the Warm Early Cenozoic.

    PubMed

    Zhang, Qian-Qian; Smith, Thierry; Yang, Jian; Li, Cheng-Sen

    2016-01-01

    The early Cenozoic was characterized by a very warm climate especially during the Early Eocene. To understand climatic changes in eastern Asia, we reconstructed the Early Eocene vegetation and climate based on palynological data of a borehole from Wutu coal mine, East China and evaluated the climatic differences between eastern Asia and Central Europe. The Wutu palynological assemblages indicated a warm temperate vegetation succession comprising mixed needle- and broad-leaved forests. Three periods of vegetation succession over time were recognized. The changes of palynomorph relative abundance indicated that period 1 was warm and humid, period 2 was relatively warmer and wetter, and period 3 was cooler and drier again. The climatic parameters estimated by the coexistence approach (CA) suggested that the Early Eocene climate in Wutu was warmer and wetter. Mean annual temperature (MAT) was approximately 16°C and mean annual precipitation (MAP) was 800-1400 mm. Comparison of the Early Eocene climatic parameters of Wutu with those of 39 other fossil floras of different age in East China, reveals that 1) the climate became gradually cooler during the last 65 million years, with MAT dropping by 9.3°C. This cooling trend coincided with the ocean temperature changes but with weaker amplitude; 2) the Early Eocene climate was cooler in East China than in Central Europe; 3) the cooling trend in East China (MAT dropped by 6.9°C) was gentler than in Central Europe (MAT dropped by 13°C) during the last 45 million years.

  11. Aerosol vertical distribution over east China from RIEMS-Chem simulation in comparison with CALIPSO measurements

    NASA Astrophysics Data System (ADS)

    Li, Jiawei; Han, Zhiwei

    2016-10-01

    The horizontal and vertical distributions of aerosol extinction coefficient (AEC) and mass concentration over east China in October 2010 were investigated by using an online-coupled regional climate model and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) data. Model performance was evaluated comprehensively against ground observations of meteorological variables and PM10 concentrations and CALIPSO retrieved AEC profiles, which demonstrated a good ability of the model in simulating spatial distribution and evolution of aerosol concentration and optical properties. Severe pollution episodes were found over wide areas of east China during the study period, with the maximum mean PM10 concentration exceeding 200 μg m-3 in the Chongqing district and a part of the lower reaches of the Yellow River on 8-10 October. Both CALIPSO retrievals and model simulations revealed high AEC values (≥1 km-1) often occurred within 2 km above ground over most areas of east China. AEC vertical profile in or in the vicinity of China major cities along CALIPSO orbit track exhibited two typical features: one was AEC reached its maximum (∼4 km-1) near the surface (<200 m) and decreased rapidly to < 0.1 km-1 at altitudes above 1 km, another one was AEC peaked at higher altitudes of about 0.5-1 km with a maximum up to 3 km-1. AEC vertical profile was strongly dependent on vertical distribution of both aerosol concentration, composition and relative humidity. The vertical cross sections over typical regions of east China exhibited a decreasing AEC in magnitude from the continent to the China seas. Over the continent, AEC was either maximum near the surface or peaked at higher altitudes (0.5-1.0 km) due to increases of relative humidity or aerosol concentration in those regions, whereas over the seas of China, AEC profile was characterized by peak values at an altitude around 1 km, mainly due to an elevated relative humidity there, which favored rapid aerosol

  12. Petrology, geochemistry and isotope data on a ultrahigh-pressure jadeite quartzite from Shuanghe, Dabie Mountains, East-central China

    NASA Astrophysics Data System (ADS)

    Liou, J. G.; Zhang, R. Y.; Jahn, Bor-ming

    1997-08-01

    In the Dabie ultrahigh-pressure terrane of east-central China, coesite-bearing jadeite quartzites occur locally as intercalated layers with marble and mafic eclogite. This rock assemblage is, in turn, enclosed within quartzofeldspathic gneisses. Metamorphic parageneses and kelyphitic textures reveal a multistage metamorphic evolution and complex exhumation history. The primary peak metamorphic assemblage consists of jadeite + garnet + coesite + rutile ± apatite. Minor coesite and coesite pseudomorphs occur as inclusions in jadeite and garnet. Three stages of retrograde assemblages are observed in the jadeite quartzites. Stage A is represented by the polymorphic transformation of coesite to quartz aggregates. Stage B is characterized by formation of coronas around jadeite porphyroblasts consisting of an inner layer of oligoclase + amphibole and an outer layer of albite ± aegirine—augite. The last stage (stage C) involved total replacement of jadeite and most garnets by taramitic amphibole + albite + aegirine-augite. Peak metamorphic P-T conditions were > 26 kbar at 660°C and are consistent with the estimates from the adjacent coesite-bearing eclogites. The jadeite quartzites display clockwise P-T path that matches those of the adjacent eclogites. Major and trace element data suggest that the protolith of the jadeite quartzite could have been an albitized siltstone enriched in Na and depleted in K and Ca. The highly negative present-day ɛNd value (-24.7) indicates a very old age for the protolith. Its late Archean model age (TDM) of 2.58 Ga is among the oldest so far identified for rocks from the Dabie UHPM terrane. Concordant field relations and petrogenetic considerations suggest that all mafic, politic, carbonate and gneissic rocks have experienced in-situ UHP metamorphism during Triassic continental collision between the Sino-Korean and Yangtze cratons.

  13. Bioavailability of dissolved organic carbon linked with the regional carbon cycle in the East China Sea

    NASA Astrophysics Data System (ADS)

    Gan, Shuchai; Wu, Ying; Zhang, Jing

    2016-02-01

    The regional carbon cycle on continental shelves has created great interest recently due to the enigma of whether these areas are a carbon sink or a source. It is vital for a precise carbon cycle model to take the bioavailability of dissolved organic carbon (DOC) into account, as it impacts the sink and source capacity, especially on dynamic shelves such as the East China Sea. Nine bio-decomposition experiments were carried out to assess differences in the bioavailability of DOC. Samples were collected from different water masses in the East China Sea, such as the Coastal Current, the Taiwan Current, and the Kuroshio Current, as well as from the Changjiang (Yangtze River), the main contributor of terrestrial DOC in the East China Sea. This study aimed to quantify and qualify bioavailable DOC (BDOC) in the East China Sea. Both the degradation constant of BDOC and the carbon output from microorganisms have been quantitatively evaluated. Qualitatively, excitation-emission matrix fluorescence spectra (EEMs) were used to evaluate the intrinsic reasons for BDOC variation. By using EEMs in conjunction with parallel factor analysis (PARAFAC), five individual fluorescent components were identified in this study: three humic-like and two protein-like components (P1, P2). The highest P1 and P2 fluorescence intensities were recorded in the coastal water during a phytoplankton algal bloom, while the lowest intensities were recorded in the Changjiang estuary. Quantitatively, BDOC observed during the incubation ranged from 0 to 26.1 μM. The DOC degradation rate constant varied from 0 to 0.027 (d-1), and was lowest in the Changjiang and highest in algal bloom water and warm shelf water (the Taiwan current). The Taiwan Current and mixed shelf water were the major contributors of BDOC flux to the open ocean, and the East China Sea was a net source of BDOC to the ocean. The results verified the importance of BDOC in regional carbon cycle modeling. Combining the data of BDOC and EEMs

  14. Distribution and source apportionment of polycyclic aromatic hydrocarbons in surface sediments from Zhoushan Archipelago and Xiangshan Harbor, East China Sea.

    PubMed

    Wang, Xiaoyan; Xu, Huanzhi; Zhou, Yongdong; Wu, Changwen; Kanchanopas-Barnette, Praparsiri

    2015-12-30

    Zhoushan Archipelago and the adjacent Xiangshan Harbor are important commercial, tourism, fishing, and mariculture areas. Considering the concern on the effects of anthropogenic activities on the environment, the level and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments were investigated. The sum of 16 PAH (∑16 PAH) concentrations in the Zhoushan Archipelago ranged from 3.67 to 31.30 ng g(-1) d.w., with a mean of 15.01 ± 1.21 ng g(-1) d.w., and that in Xiangshan Harbor varied from 11.58 to 481.44 ng g(-1) d.w., with a mean of 62.52 ± 32.85 ng g(-1) d.w. Diagnostic ratios and factor analysis were performed to identify PAH sources. Results show that PAHs have mixed origins (i.e., traffic-related sources, coal combustion, petrogenic sources, and biomass burning), with pyrolytic-related pollution as the dominant source. This study provided a baseline to promote environmental protection and pollution episode monitoring in the East China Sea.

  15. Communities of sediment ammonia-oxidizing bacteria along a coastal pollution gradient in the East China Sea.

    PubMed

    Hou, Manhua; Xiong, Jinbo; Wang, Kai; Ye, Xiansen; Ye, Ran; Wang, Qiong; Hu, Changju; Zhang, Demin

    2014-09-15

    Anthropogenic nitrogen (N) discharges has caused eutrophication in coastal zones. Ammonia-oxidizing bacteria (AOB) convert ammonia to nitrite and play important roles in N transformation. Here, we used pyrosequencing based on the amoA gene to investigate the response of the sediment AOB community to an N pollution gradient in the East China Sea. The results showed that AOB assemblages were primarily affiliated with Nitrosospira-like lineages, and only 0.4% of those belonged to Nitrosomonas-like lineage. The Nitrosospira-like lineage was separated into four clusters that were most similar to the sediment AOB communities detected in adjacent marine regions. Additionally, one clade was out grouped from the AOB lineages, which shared the high similarities with pmoA gene. The AOB community structures substantially changed along the pollution gradient, which were primarily shaped by NH4(+)-N, NO3(-)-N, SO4(2)(-)-S, TP and Eh. These results demonstrated that coastal pollution could dramatically influence AOB communities, which, in turn, may change ecosystem function.

  16. Investigation of Anthrax Cases in North-East China, 2010-2014

    PubMed Central

    Zhou, Wei; Sun, Yang; Zhu, Lingwei; Zhou, Bo; Liu, Jun; Ji, Xue; Wang, Xiaofeng; Wang, Nan; Gu, Guibo; Feng, Shuzhang; Qian, Jun; Guo, Xuejun

    2015-01-01

    We determined the genotypes of seven Bacillus anthracis strains that were recovered from nine anthrax outbreaks in North-East China from 2010 to 2014, and two approved vaccine strains that are currently in use in China. The causes of these cases were partly due to local farmers being unaware of the presence of anthrax, and butchers with open wounds having direct contact with anthrax-contaminated meat products. The genotype of five of the seven recovered strains was A.Br.001/002 sub-lineage, which was concordant with previously published research. The remaining two cases belongs to the A.Br.Ames sub-lineage. Both of these strains displayed an identical SNR pattern, which was the first time that this genotype was identified in North-East China. Strengthening education in remote villages of rural China is an important activity aimed at fostering attempts to prevent and control anthrax. The genotype of the vaccine strain Anthrax Spore Vaccine No.II was A.Br.008/009 and A.Br.001/002 for the vaccine strain Anthrax Spore Vaccine Non-capsulated. Further studies of their characteristics are clearly warranted. PMID:26308449

  17. Investigation of Anthrax Cases in North-East China, 2010-2014.

    PubMed

    Zhou, Wei; Sun, Yang; Zhu, Lingwei; Zhou, Bo; Liu, Jun; Ji, Xue; Wang, Xiaofeng; Wang, Nan; Gu, Guibo; Feng, Shuzhang; Qian, Jun; Guo, Xuejun

    2015-01-01

    We determined the genotypes of seven Bacillus anthracis strains that were recovered from nine anthrax outbreaks in North-East China from 2010 to 2014, and two approved vaccine strains that are currently in use in China. The causes of these cases were partly due to local farmers being unaware of the presence of anthrax, and butchers with open wounds having direct contact with anthrax-contaminated meat products. The genotype of five of the seven recovered strains was A.Br.001/002 sub-lineage, which was concordant with previously published research. The remaining two cases belongs to the A.Br.Ames sub-lineage. Both of these strains displayed an identical SNR pattern, which was the first time that this genotype was identified in North-East China. Strengthening education in remote villages of rural China is an important activity aimed at fostering attempts to prevent and control anthrax. The genotype of the vaccine strain Anthrax Spore Vaccine No.II was A.Br.008/009 and A.Br.001/002 for the vaccine strain Anthrax Spore Vaccine Non-capsulated. Further studies of their characteristics are clearly warranted.

  18. Tectonic structure of Dokdo and adjacent area in the northeastern part of the Ulleung Basin of the East Sea using geophysical data

    NASA Astrophysics Data System (ADS)

    Kim, C.; Jeong, E.; Park, C.; Kwon, B.; Park, G.; Park, J.

    2008-12-01

    The northeastern part of the Ulleung Basin in the East Sea is composed of volcanic islands (Ulleungdo and Dokdo), seamounts (the Anyongbok Seamount, the Simheungtaek and the Isabu Tablemounts), and a deep pathway (Korea Gap). To understand tectonic structure and geophysical characteristics of Dokdo and adjacent area, We analysed geophysical potential data of KORDI(Korea Ocean Research and Development Institute), KIGAM(Korea Institute of Geoscience and Mineral Resources), and NORI(National Oceanographic Research Institute of Korea) around the Dokdo volcanic body except Ulleung Do because of empty data of its large island. Also, we eliminate the effect of water and sediments from the free-air gravity data to process 3D Moho depth inversion. 3D tectonic structure modelling of the study area was developed using Moho depth inversion result and sediment thickness data of NGDC(National Geophysical Data Center). The free-air gravity anomalies of the study area generally reflect bathymetric effects. Although the Dokdo seamounts have a similar topographic size, the decrease of free-air anomaly toward Isabu suggest that Isabu is oldest among the seaounts and have high degree of isostatic compensation. High Bouguer anomalies in the central part of the Ulleung Basin gradually decreases toward the Oki Bank. This feature suggests that the crust/mantle boundary is shallow in the central part of the Ulleung Basin. The complex magnetic pattern of Dokdo suggests that it might have erupted several times during its formation. The magnetic anomaly amplitude of Isabu is much smaller than that of Dokdo. Such low magnetic anomalies are attributed to a secondary change caused by the metamorphism or weathering of ferromagnetic minerals of the seamount during a long period of time after its formation. Analytic signals show high anomalous zones over volcanoes. Also, there are high analytic signal values in Korea Gap indicating magmatic intrusion in thick sediments. The power spectrum analysis

  19. A historical perspective of the extremely hot 2013 summer in East-central China

    NASA Astrophysics Data System (ADS)

    Liu, Qi; Fu, Congbin; Mao, Huiting

    2016-04-01

    An extreme hot summer occurred over East-central China in 2013. Its duration of continuous, highest temperature anomalies was the longest on record for the time period of 1948-2013. Several modeling studies have attempted to identify the causes and did not obtain conclusive findings, in large part due to their limited scopes of the problem. Here, we conducted a multi-scale and multi-factor analysis of this extreme event using observational data of 600 monitoring stations over China and global reanalysis data for the period of 1981-2013. Our results suggested that the number of heatwave days (NHD) (defined as a day with daily maximum temperature ≥ 35°C) over East-central China experienced an increasing trend of 3.44 days per decade since 1981 and reached the record maximum (34.1 days) in 2013, with significant inter-annual variability superimposed on the trend. It should be noted that this increasing trend in NHD was consistent with that of the intensity of the Western Pacific Subtropical High (WPSH) linked to global warming as suggested in the literature. There were also strong correlations between NHD over East-central China, WPSH, and global mean temperature (GT) on interannual scales. The extremely hot 2013 summer could not be explained by global warming and associated enhanced WPSH alone as GT and WPSH intensity were not record high in that summer. Further analysis suggested that large scale air-sea interaction over the Pacific region could have played a critical role. Specifically, enhanced convection over the Philippine Sea and along Indonesian islands in summer 2013 appeared to be strongest for the study period. This convection could cause a strong local feedback among precipitation, cloud cover, and net radiation, which could further weaken upper- and lower-level circulation via the tropical-extratropical teleconnection and Rossby wave propagation. This feedback was likely the direct cause of the extremely hot 2013 summer.

  20. Viral metagenomics analysis of planktonic viruses in East Lake, Wuhan, China.

    PubMed

    Ge, Xingyi; Wu, Yongquan; Wang, Meiniang; Wang, Jun; Wu, Lijun; Yang, Xinglou; Zhang, Yuji; Shi, Zhengli

    2013-10-01

    East Lake (Lake Donghu), located in Wuhan, China, is a typical city freshwater lake that has been experiencing eutrophic conditions and algal blooming during recent years. Marine and fresh water are considered to contain a large number of viruses. However, little is known about their genetic diversity because of the limited techniques for culturing viruses. In this study, we conducted a viral metagenomic analysis using a high-throughput sequencing technique with samples collected from East Lake in Spring, Summer, Autumn, and Winter. The libraries from four samples each generated 234,669, 71,837, 12,820, and 34,236 contigs (> 90 bp each), respectively. The genetic structure of the viral community revealed a high genetic diversity covering 23 viral families, with the majority of contigs homologous to DNA viruses, including members of Myoviridae, Podoviridae, Siphoviridae, Phycodnaviridae, and Microviridae, which infect bacteria or algae, and members of Circoviridae, which infect invertebrates and vertebrates. The highest viral genetic diversity occurred in samples collected in August, then December and June, and the least diversity in March. Most contigs have low-sequence identities with known viruses. PCR detection targeting the conserved sequences of genes (g20, psbA, psbD, and DNApol) of cyanophages further confirmed that there are novel cyanophages in the East Lake. Our viral metagenomic data provide the first preliminary understanding of the virome in one freshwater lake in China and would be helpful for novel virus discovery and the control of algal blooming in the future.

  1. Spatial variability of dissolved phosphorous concentrations and alkaline phosphatase activity in the East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, H.; Chang, J.; Ho, T.; Gong, G.

    2010-12-01

    The concentrations of dissolved inorganic phosphorus (DIP) and alkaline phosphatase activity (APA) have been determined at about 25 sampling stations in the East China Sea since 2003. The stations are mainly distributed from the Changjiang river mouth to northern Taiwan and east to the shelf break. In addition to the Changjiang discharge, we have found a specific nutrient source around a coastal site (122° 2’30’’ E, 28° 40’ N). Elevated DIP and nitrate concentrations have been constantly observed around the sampling station for 8 years, where the surface DIP concentrations are generally around 0.3 µM. The nutrient source may either originate from ground water discharge or coastal upwelling, where lower temperature has been observed in the water column around the station. In general, APA has been negatively correlated with DIP concentrations in the studies sites, with lowest APA around the high DIP station and the Changjiang river mouth.

  2. Survey of nitrite content in foods from north-east China.

    PubMed

    Yuan, Y; Zhang, T; Zhuang, H; Wang, K; Zheng, Y; Zhang, H; Zhou, B; Liu, J

    2010-01-01

    This study reports a survey of nitrite in a variety of foods consumed in north-east China and estimates the intake of nitrite for the north-east Chinese consumer. A total of 642 food categories including rice and rice products, flour and flour products, soybean and products, vegetables, fruit, preserved vegetables, cured meat products, dairy products, fish products, salt, and soy sauce were analysed for their content of nitrite. Nitrite content was quite different both between different food categories and within the same food category, ranging from not determined (n.d.) to 19.7 mg kg(-1). A great variation in the content of nitrite was found for all the food products. The average content of nitrite was highest in cured meat products (14.3 mg kg(-1)). Next to that, the nitrite content was high in the order of preserved vegetables (4.1 mg kg(-1)), soybean products (3.5 mg kg(-1)), and dairy products (1.9 mg kg(-1)). The lowest average values of nitrite were detected in soy sauce, rice and rice products, salt and fish products, the contents being 0.1, 0.3, 0.3, and 0.6 mg kg(-1). Calculations on the basis of these results and including dietary surveys show that the average intake of nitrite in north-east China from food was 0.03 mg kg(-1) body weight for an average Chinese person weighing 60 kg, and the data are lower than the established acceptable daily intake (ADI) for nitrite. Cured meat products are normally the major contributor to average nitrite intake of the north-east Chinese population. The second contributor is vegetables.

  3. Crust structure of the Northern Margin of North China Craton and adjacent region from Sinoprobe-02 North China seismic WAR/R experiment

    NASA Astrophysics Data System (ADS)

    Li, W.; Gao, R.; Keller, G. R.; Li, Q.; Cox, C. M.; Hou, H.; Guan, Y.

    2011-12-01

    The Central Asian Orogen Belt (CAOB) or Altaids, situated between the Siberian craton(SC) to the north and north China craton (NCC) with tarim to the south, is one of the world's largest accretionary orogens formed by subduction and accretion of juvenile material from the Neoproterozoic through the Paleozoic. The NCC is the oldest craton in China, which suffered Yanshan intercontinental orogenic process and lithosphere thinning in Mesozoic. In the past 20 years, remarkable studies about this region have been carried out and different tectonic models were proposed, however, some crucial geologic problems remain controversial. In order to obtain better knowledge of deep structure and properties of crust on the northern margin of north China craton, a 450 km long WAR/R section was completed jointly by Institute of Geology, CAGS and University of Oklahoma. Our 450 km long NW-SE WAR/R line extends from west end of the Yanshan orogen, across the Bainaimiao arc, Ondor sum subduction accretion complex to the Solonker suture zone. The recording of seismic waves from 8 explorations was conducted in 4 deployments of 300 reftek-125A records and single-channel 4.5Hz geophones with station spacing of 1km. The shooting procedure was employ 500 or 1500kg explosives in 4-5 or 15-23 boreholes at 40-45m depth. The sampling rate was 100 HZ, and recording time window was 1200s. The P wave field on the sections got high quality data for most part of the profile, but have low signal-to-noise for the south end, where closed to Beijing with a lot of ambient noise from traffic, industry and human activity. Arrivals from of refracted and reflected waves from sediments and basement (Pg), intracrust (Pcp, Plp) and Moho (Pmp) were typically observed, but Pn phase through the upper most mantle was only observed for 2 shots. Identification and correlation of seismic phases was done manually on computer screen Zplot software. Each trace has been bandpass filtered (1-20Hz) and normalized with AGC

  4. Coastal Wind Energy Assessment in the East China Sea with SAR Imagery

    NASA Astrophysics Data System (ADS)

    Lou, Xiulin; Chang, Junfang; Shi, Aiqin

    2013-01-01

    The development of offshore wind farm needs accurate assessment of coastal wind energy. With the development of satellite remote sensing technology, synthetic aperture radar (SAR) provides new methods for coastal wind energy resources assessment. In this study, coastal wind energy remote sensing technology based on space-borne SAR is researched. A long time sequence of sea surface wind speed data in the Zhejiang Coastal Waters (ZCW) of the East China Sea were retrieved from ENVISAT ASAR imagery. Based on the wind speed data, the wind energy resources in ZCW were assessed accurately. The spatial and temporal distribution characteristics of the wind energy resources in ZCW were also investigated and analyzed.

  5. Polychlorinated biphenyl (PCB) congeners in Mussel and other mollusc from Da Chen Island, East China Sea

    SciTech Connect

    Chu, S.G.; Xi, Z.Q.; Xu, X.B

    1995-11-01

    Polychlorinated biphenyls (PCBs) are among the most persistent and toxic pollutants in environment. Determination of these contaminants in fish, shellfish and other mollusc is very important, not only because these aquatics are important food for mankind, but also because they can bioconcentrate contaminants preferentially in their adipose tissue, and serve as biomarker of the aquatic pollution. Mussels and oysters have been widely used to monitor the pollution in the coastal environment. The aim of the study was to investigate the concentrations and the main source of PCBs in mussels and other mollusca from the coastal areas of East China Sea. 10 refs., 3 figs., 2 tabs.

  6. Distribution characteristics of marine litter on the sea bed of the East China Sea and the South Sea of Korea

    NASA Astrophysics Data System (ADS)

    Lee, Dae-In; Cho, Hyeon-Seo; Jeong, Sun-Beom

    2006-10-01

    The types, quantities, and distribution of marine litter found on the sea bed of the East China Sea and the South Sea of Korea are surveyed. Surveys were evaluated using bottom trawl nets during 1996-2005 cruises. Mean distribution densities were high in coastal seas, especially in the South Sea of Korea offshore from Yeosu, with 109.8 kg km -2, and low in the East China Sea, with densities of 30.6 kg km -2. Fishing gear, such as pots, nets, octopus jars, and fishing lines, accounted for about 42-72% and 37-62% of litter items in the East China Sea and the South Sea of Korea, respectively, whereas the contributions of rubber, vinyl, metal, plastic, glass, wood, and clothing were below 30% mainly. Rope and drum composition fluctuated greatly, between 54% and 0%. Eel and net pots dominated the marine debris of the South Sea of Korea, and some vinyl, plastics, and fishing gear made in Korea, China, and Japan were collected in abundance in the East China Sea. Fishing gear was probably discarded into the sea, deliberately or inadvertently, by fishing operations. A comprehensive joint approach by Korea, China, and Japan is needed for the continuous monitoring of input sources, the actual conditions, and the behavior of marine litter for protection against litter pollution and fisheries resource management in this area.

  7. Distribution of Bottom Trawling Effort in the Yellow Sea and East China Sea

    PubMed Central

    Zhang, Shengmao; Jin, Shaofei; Zhang, Heng; Fan, Wei; Tang, Fenghua; Yang, Shenglong

    2016-01-01

    Bottom trawling is one of the most efficient fishing activities, but serious and persistent ecological issues have been observed by fishers, scientists and fishery managers. Although China has applied the Beidou fishing vessel position monitoring system (VMS) to manage trawlers since 2006, little is known regarding the impacts of trawling on the sea bottom environments. In this study, continuous VMS data of the 1403 single-rig otter trawlers registered in the Xiangshan Port, 3.9% of the total trawlers in China, were used to map the trawling effort in 2013. We used the accumulated distance (AD), accumulated power distance (APD), and trawling intensity as indexes to express the trawling efforts in the Yellow Sea (YS) and East China Sea (ECS). Our results show that all three indexes had similar patterns in the YS and ECS, and indicated a higher fishing effort of fishing grounds that were near the port. On average, the seabed was trawled 0.73 times in 2013 over the entire fishing region, and 51.38% of the total fishing grounds were with no fishing activities. Because of VMS data from only a small proportion of Chinese trawlers was calculated fishing intensity, more VMS data is required to illustrate the overall trawling effort in China seas. Our results enable fishery managers to identify the distribution of bottom trawling activities in the YS and ECS, and hence to make effective fishery policy. PMID:27855215

  8. Eutrophication-Driven Hypoxia in the East China Sea off the Changjiang Estuary.

    PubMed

    Wang, Hongjie; Dai, Minhan; Liu, Jinwen; Kao, Shuh-Ji; Zhang, Chao; Cai, Wei-Jun; Wang, Guizhi; Qian, Wei; Zhao, Meixun; Sun, Zhenyu

    2016-03-01

    Coastal hypoxia is an increasingly recognized environmental issue of global concern to both the scientific community and the general public. We assessed the relative contributions from marine and terrestrially sourced organic matter that were responsible for oxygen consumption in a well-studied seasonal coastal hypoxic zone, the East China Sea off the Changjiang Estuary. Our fieldwork was conducted in August 2011 during reinstatement of a subsurface hypoxia, when we observed a continuous decline of dissolved oxygen along with production of dissolved inorganic carbon resulting from organic carbon remineralization. On the basis of a three end-member mixing model and determinations of the stable isotopic compositions of dissolved inorganic carbon (δ(13)CDIC), the end product of particulate organic carbon (POC) degradation, we quantified the δ(13)C value of the remineralized organic carbon (δ(13)COCx), which was -18.5 ± 1.0‰. This isotopic composition was very similar to the δ(13)C of marine sourced POC produced in situ (-18.5 ± 0.3‰) rather than that of the terrestrially sourced POC (-24.4 ± 0.2‰). We concluded that marine-sourced organic matter, formed by eutrophication-induced marine primary production, was the dominant oxygen consumer in the subsurface hypoxic zone in the East China Sea off the Changjiang Estuary.

  9. Vertical distribution and indications of lipids biomarkers in the sediment core from East China Sea

    NASA Astrophysics Data System (ADS)

    Wang, Rui; Wang, Jiangtao; Li, Feng; Yang, Shu; Tan, Liju

    2016-07-01

    To study the distribution and indications of lipids biomarkers in the mud areas of the East China Sea shelf, a sediment core was collected. Lipids were determined to find the origination of different organic matter (fatty acids and sterols) inputs. The results demonstrated that the distribution of fatty acids and sterols indicated the organic matter derived from the mixed allochthonous and autochthonous sources, but mainly autochthonous. The total fatty acids concentrations ranged from 29.08 μg g-1 to 303.92 μg g-1 and exhibited unimodal distribution with the predominance of C16-fatty acid. Neutral lipid concentrations ranged from 1.77 μg g-1 to 4.65 μg g-1. Furthermore, the distribution patterns of sterols varied with depth, and were dominated by C27-sterol and C29-sterol in the top and bottom sediments respectively. Although bacterial lipids were recruited during diagenesis, the refractory terrestrial lipids were usually preferentially preserved. This records dated from the 1980s suggested that the phytoplankton community was mainly influenced by eutrophication in the East China Sea and this variation may be recorded by lipid biomarkers deposited in the sediment.

  10. Detecting the red tide based on remote sensing data in optically complex East China Sea

    NASA Astrophysics Data System (ADS)

    Xu, Xiaohui; Pan, Delu; Mao, Zhihua; Tao, Bangyi; Liu, Qiong

    2012-09-01

    Red tide not only destroys marine fishery production, deteriorates the marine environment, affects coastal tourist industry, but also causes human poison, even death by eating toxic seafood contaminated by red tide organisms. Remote sensing technology has the characteristics of large-scale, synchronized, rapid monitoring, so it is one of the most important and most effective means of red tide monitoring. This paper selects the high frequency red tides areas of the East China Sea as study area, MODIS/Aqua L2 data as the data source, analysis and compares the spectral differences in the red tide water bodies and non-red tide water bodies of many historical events. Based on the spectral differences, this paper develops the algorithm of Rrs555/Rrs488> 1.5 to extract the red tide information. Apply the algorithm on red tide event happened in the East China Sea on May 28, 2009 to extract the information of red tide, and found that the method can determine effectively the location of the occurrence of red tide; there is a good corresponding relationship between red tide extraction result and chlorophyll a concentration extracted by remote sensing, shows that these algorithm can determine effectively the location and extract the red tide information.

  11. Four newly recorded free-living marine nematodes (Comesomatidae) from the East China Sea

    NASA Astrophysics Data System (ADS)

    Hua, Er; Zhang, Zhinan

    2007-01-01

    Three species in genus Sabatieria and one in genus Cervonema from the East China Sea were recorded. S. breviseta is characterized by uniformly punctuated coarse dots, large amphids of 5.5 turns (♂) and prominent gubernaculum median piece. The characters of S. breviseta agree quite well with the European original descriptions and only differ in the male amphid turns (5.5 vs. 4.0 turns) and unmodified preanal supplements (5-7 vs. 6). S. pulchra can be recognized by amphid 2.75 turns, irregularly arranged lateral dots, and the first three supplements anterior to the anus, which are more widely spaced than the following ones. The excretory system of S. breviseta and S. pulchra shows sexual dimorphism. S. celtica is defined by amphids 2.00-2.25 turns, weakly developed pharyngeal bulb, curved apophyses and 12-13 conspicuous supplements. C. deltensis is characterized by amphids 4.75 turns, ovate pharyngeal posterior bulb, sperm dimorphism, 7 thin preanal supplements, and long tail cylindrical portion (50%-53% of tail length). All the three Sabatieria species are for the first time recorded in Chinese waters. C. deltensis was originally isolated from the Bohai Sea and Yellow Sea and newly recorded in the East China Sea.

  12. Internal wave damping in the East China in late summer 2014

    NASA Astrophysics Data System (ADS)

    Kuh Kang, Sok; Lee, Jae Hak; Park, Jae-Hun; Kim, Eun Jin; Hong, Chang Su

    2016-04-01

    A field measurement was carried out to observe generation, propagation and damping of the internal waves on the continental shelf around 31N in the East China Sea during September 16-27, 2014. Two trawl-resistant bottom mount ADCPs (M1, M2) were deployed along 126.5oE with 10 km apart. Over the 10 km distance the dominant frequency internal wave group with periods around 500 s is estimated to dissipate its energy by about 30%. The damping process appears to be partly related with the higher-mode evolution at the downward station M1, compared with the 1st-mode dominancy at the upstream station (M2). Our observations suggest that the damping processes of internal waves on the continental shelf of the East China Sea occur by rather complicated manners than by the simple process due to frictional decaying. This work was partially supported by KIOST projects (PE99396)and this research has been performed as collaborative research project of project No (Development of HPC-based management system againstnational scale disaster) and supported by the KOREA INSTITUTE of SCIENCE and TECHNOLOGY INFORMATION (KISTI).

  13. Sulfate reduction and iron sulfide mineral formation in the southern East China Sea continental slope sediment

    NASA Astrophysics Data System (ADS)

    Lin, Saulwood; Huang, Kuo-Ming; Chen, Shin-Kuan

    2002-10-01

    Sulfate reduction rate, organic carbon and sulfide burial rate; organic carbon, carbonate carbon, and reactive iron contents; grain size; and sedimentation rate were determined in sediments of the southern East China Sea continental slope. The results show high sulfate reduction and pyrite sulfur burial rates in slope areas with high organic carbon and sedimentation rates. Unusually high rates of organic carbon deposition enhance sulfate reduction and pyrite sulfide burial in the region. Both sulfate reduction rates and pyrite sulfur burial rates increased linearly with increasing organic carbon burial rate, indicating that deposition of organic carbon on the slope is the primary controlling factor for pyrite formation. Abundant reactive iron indicated that iron is not limiting pyrite formation. Pyrite is the predominant sulfide mineral; however, acid volatile sulfide constituted up to 50% of total sulfide at some stations. Up to 240 μmol/g of pyrite sulfur and 5 mmol/m 2/day of sulfate reduction rates were found in the slope sediment. Sulfate reduction rate and pyrite sulfur did not decrease with increasing overlying water depth. High organic carbon burial rates enhanced the sulfate reduction rate and subsequently the rate of pyrite sulfur burial in the slope region. As a result, the southern East China Sea continental slope environment is an efficient pyrite sulfur burial environment.

  14. Unusual distribution of floating seaweeds in the East China Sea in the early spring of 2012.

    PubMed

    Komatsu, Teruhisa; Mizuno, Shizuha; Natheer, Alabsi; Kantachumpoo, Attachai; Tanaka, Kiyoshi; Morimoto, Akihiko; Hsiao, Sheng-Tai; Rothäusler, Eva A; Shishidou, Hirotoshi; Aoki, Masakazu; Ajisaka, Tetsuro

    2014-01-01

    Floating seaweeds play important ecological roles in offshore waters. Recently, large amounts of rafting seaweed have been observed in the East China Sea. In early spring, juveniles of commercially important fish such as yellowtail accompany these seaweed rafts. Because the spatial distributions of seaweed rafts in the spring are poorly understood, research cruises were undertaken to investigate them in 2010, 2011, and 2012. Floating seaweed samples collected from the East China Sea during the three surveys contained only Sargassum horneri. In 2010 and 2011, seaweed rafts were distributed only in the continental shelf and the Kuroshio Front because they had become trapped in the convergence zone of the Kuroshio Front. However, in 2012, seaweed was also distributed in the Kuroshio Current and its outer waters, and massive strandings of seaweed rafts were observed on the northern coast of Taiwan and on Tarama Island in the Ryukyu Archipelago. Environmental data (wind, currents, and sea surface height) were compared among the surveys of 2010, 2011, and 2012. Two factors are speculated to have caused the unusual distribution in 2012. First, a continuous strong north wind produced an Ekman drift current that transported seaweed southwestward to the continental shelf and eventually stranded seaweed rafts on the coast of Taiwan. Second, an anticyclonic eddy covering northeast Taiwan and the Kuroshio Current west of Taiwan generated a geostrophic current that crossed the Kuroshio Current and transported the rafts to the Kuroshio Current and its outer waters. Such unusual seaweed distributions may influence the distribution of fauna accompanying the rafts.

  15. Nitrogen mineralization and immobilization in sediments of the East China Sea: Spatiotemporal variations and environmental implications

    NASA Astrophysics Data System (ADS)

    Lin, Xianbiao; Hou, Lijun; Liu, Min; Li, Xiaofei; Zheng, Yanling; Yin, Guoyu; Gao, Juan; Jiang, Xiaofen

    2016-11-01

    Nitrogen (N) mineralization and immobilization are important processes of N biogeochemical cycle in marine sediments. This study investigated gross N mineralization (GNM) and NH4+ immobilization (GAI) in the sediments from the East China Sea (ESC), using 15N stable isotope dilution technique. Results show that measured rates of GNM and GAI ranged from 0.04 to 6.1 µg N g-1 d-1 and from undetectable to 9.82 µg N g-1 d-1, respectively. In general, both GNM and GAI rates were significantly greater in summer as compared to winter, and the high rates occurred mainly in the muddy area and increased gradually from the Yangtze Estuary to Zhe-Min Coastal muddy areas. The GNM and GAI processes were related closely to sediment temperature, pH, ammonium (NH4+), nitrate (NO3-), total organic carbon (TOC), and total nitrogen (TN) contents in the muddy area, while they were associated tightly with sediment temperature, pH, NH4+, TOC, TN, sulfide, and Fe(III) concentrations in the sandy area. In addition, the total mineralized and immobilized N in the East China Sea (ECS) were estimated to be approximately 2.1 × 106 t N yr-1 and 2.7 × 106 t N yr-1, respectively. Overall, these results highlight the importance of N mineralization and immobilization in controlling the N budget in the ECS and improve the understanding of both processes and associated controlling mechanisms in the coastal marine ecosystem.

  16. Diurnal variation of surface ozone in mountainous areas: Case study of Mt. Huang, East China.

    PubMed

    Zhang, Lei; Jin, Lianji; Zhao, Tianliang; Yin, Yan; Zhu, Bin; Shan, Yunpeng; Guo, Xiaomei; Tan, Chenghao; Gao, Jinhui; Wang, Haoliang

    2015-12-15

    To explore the variations in atmospheric environment over mountainous areas, measurements were made from an intensive field observation at the summit of Mt. Huang (30.13°N, 118.15°E, 1841m above sea level), a rural site located in East China, from June to August 2011. The measurements revealed a diurnal change of surface O3 with low concentrations during the daytime and high concentrations during the nighttime. The causes of diurnal O3 variations over the mountain peak in East China were investigated by using a fairly comprehensive WRF-Chem and HYSPLIT4 modeling approach with observational analysis. By varying model inputs and comparing the results to a baseline modeling and actual air quality observations, it is found that nearby ozone urban/anthropogenic emission sources were contributing to a nighttime increase in mountaintop ozone levels due to a regional transport lag and residual layer effects. Positive correlation of measured O3 and CO concentrations suggested that O3 was associated with anthropogenic emissions. Sensitivity modeling experiments indicated that local anthropogenic emissions had little impact on the diurnal pattern of O3. The diurnal pattern of O3 was mainly influenced by regional O3 transport from the surrounding urban areas located 100-150km away from the summit, with a lag time of 10h for transport.

  17. Newly recorded Karlodinium veneficum dinoflagellate blooms in stratified water of the East China Sea

    NASA Astrophysics Data System (ADS)

    Dai, Xinfeng; Lu, Douding; Guan, Weibing; Wang, Hongxia; He, Piaoxia; Xia, Ping; Yang, Huajie

    2014-03-01

    Karlodinium veneficum is a cosmopolitan species, but has been poorly recorded in the East China Sea (ECS) due to its small size and difficulty in identification. The bloom dynamics of this species is not well understood globally. In this study, we examined its morphological characteristics that suggest the K. veneficum is the co-occurring bloom causative species of large scale Prorocentrum donghaiense blooms in spring 2011. The epicone of K. veneficum recorded in the investigated area is conical or rounded, and the hypocone is hemispherically rounded. The ventral pore is located at the left side of the apical groove. Nucleus is positioned centrally within the hypocone. Four large irregular chloroplasts are equally distributed in the epicone and hypocone. The mean length of cultured cells was 13.6±1.2 μm (range 11.0-15.8 μm) and the mean width was 10.0±1.1 μm (range 8.0-12 μm) (n=50). Cell abundance of K. veneficum population was low, in the region 1000-1600 cells L-1, along a transect in the East China Sea on April 19, 2011, when the water column was not distinctly stratified. Cell densities reached 3×107 cells L-1 along the same transect on May 13 2011 when the bloom occurred in the 10 m layer surface and the water column was distinctly stratified. Cell abundances therefore appear closely related to water column stratification.

  18. Structural evolution of the East China Sea and the relationship with oil and gas

    SciTech Connect

    Wu, Xianghong; Duan, Chang

    1995-12-31

    The East China Sea (ECH) is a Cenozoic sedimentary basin, lying on the Pre-Cretaceous basement. During Cenozoic Era, the basin went through three development stages: the half-graben, domnwarping depression, and regional subsidence. Analyzed the data from gravity, magnetism, reflection seismology measurements, the structural pattern of the ECS can be decided: east-west zone of the NE-or NNE-trending structural belts and a south-north differentiation of structural blocks. From west to east the structural belts are the Zhe-min uplift, the shelf basin, Diaoyu island uplift, Okinawa trough basin and Ryukyu islands. This structural pattern is controlled by the activity of the Eurasia plate and the Pacific plate, which can be interpreted from the data of the earthquake and the structural stress field. Calculating of Moho and Curie, and 2-D modeling of gravity and magnetism data help constrain the seismic interpretation and understood the faults and structure. Modeling of sedimentary and thermal history help find the region of generation oil.

  19. Spatial variations in the Kuroshio nutrient transport from the East China Sea to south of Japan

    NASA Astrophysics Data System (ADS)

    Guo, X. Y.; Zhu, X.-H.; Long, Y.; Huang, D. J.

    2013-04-01

    Based on absolute geostrophic velocity calculated from repeated hydrographic data of 39 cruises from 2000 to 2009 and nitrate concentrations measured at the same sections from 1964 to 2011, we obtained temporally averaged nitrate flux (the product of velocity and nitrate concentration) and nitrate transport (integration of flux over a section) through 4 sections along the Kuroshio path from the East China Sea (sections PN and TK) to south of Japan (sections ASUKA and 137E). In addition, we examined section OK east of the Ryukyu Islands in order to understand the contribution of Ryukyu Current to the Kuroshio nutrient transport south of Japan. The mean nitrate flux shows a subsurface maximum core with a value of 10, 10, 11, 11, and 6 mol m-2 s-1 at sections PN, TK, ASUKA, 137E, and OK, respectively. The depth of subsurface maximum core changes among five sections and is approximately 400, 500, 500, 400, and 800 m at sections PN, TK, ASUKA, 137E, and OK respectively. The mean downstream nitrate transport is 199.3, 176.3, 909.2, 1385.5, and 341.2 kmol m-1 at sections PN, TK, ASUKA, 137E, and OK respectively. The nutrient transports at these sections suggest the presence of Kuroshio nutrient stream from its upstream region to downstream. The deep current structure of Ryukyu Current (section OK) makes it contribute more nitrate transport than the Kuroshio in the East China Sea (section TK) to the Kuroshio south of Japan. In addition, the positive difference between the downstream nitrate transport through section ASUKA and the sum of nitrate transports through sections TK and OK, as well as the positive difference of downstream nitrate transport between sections 137E and ASUKA, suggest that the Kuroshio recirculation significantly intensifies the downstream (eastward) nitrate transport by the Kuroshio.

  20. An optimal index for measuring the effect of East Asian winter monsoon on China winter temperature

    NASA Astrophysics Data System (ADS)

    Hu, Chundi; Yang, Song; Wu, Qigang

    2015-11-01

    Extreme cold events occur frequently in China. The authors define a representative yet simple index to reveal the monthly changes in China winter temperature associated with the East Asian winter monsoon (EAWM), which is represented by both the leading empirical orthogonal function (EOF) mode and the country-mean temperature index of Chinese 160 gauge stations. A combined technique of correlation and multivariate EOF (Corr-MVEOF) analyses is applied to capture the dominant coupled patterns of EAWM circulation system. Based on the atmospheric circulation features captured by the leading Corr-MVEOF mode, a new EAWM index referred to as CNWMI is derived by using a stepwise regression analysis. The CNWMI highlights the importance of (1) the Mongolia-Siberian High (MSH) and its southward expansion and (2) the Asia-wide meridional dipole anomaly of 500 hPa geopotential height. Compared with the 27 existing EAWM indices, the CNWMI not only best represents the leading modes of both EAWM circulation system and China winter temperature, but also reasonably tracks the intraseasonal-to-interdecadal variations of EAWM so that the monthly intensity of EAWM can be monitored conveniently. In particular, the Aleutian low (AL) is not strongly related to the MSH and may not be responsible for the variability of EAWM/MSH. Moreover, the indices that are highly correlated with the temperature over southern East Asia do not show significant relationships with the AL, which is different from the conventional concept that a strong EAWM/MSH is linked to a deepened AL. In contrast, the anomalous Australia-Maritime Continent low is in good agreement with the variation of EAWM/MSH.

  1. Monitoring schistosomiasis risk in East China over space and time using a Bayesian hierarchical modeling approach.

    PubMed

    Hu, Yi; Ward, Michael P; Xia, Congcong; Li, Rui; Sun, Liqian; Lynn, Henry; Gao, Fenghua; Wang, Qizhi; Zhang, Shiqing; Xiong, Chenglong; Zhang, Zhijie; Jiang, Qingwu

    2016-04-07

    Schistosomiasis remains a major public health problem and causes substantial economic impact in east China, particularly along the Yangtze River Basin. Disease forecasting and surveillance can assist in the development and implementation of more effective intervention measures to control disease. In this study, we applied a Bayesian hierarchical spatio-temporal model to describe trends in schistosomiasis risk in Anhui Province, China, using annual parasitological and environmental data for the period 1997-2010. A computationally efficient approach-Integrated Nested Laplace Approximation-was used for model inference. A zero-inflated, negative binomial model best described the spatio-temporal dynamics of schistosomiasis risk. It predicted that the disease risk would generally be low and stable except for some specific, local areas during the period 2011-2014. High-risk counties were identified in the forecasting maps: three in which the risk remained high, and two in which risk would become high. The results indicated that schistosomiasis risk has been reduced to consistently low levels throughout much of this region of China; however, some counties were identified in which progress in schistosomiasis control was less than satisfactory. Whilst maintaining overall control, specific interventions in the future should focus on these refractive counties as part of a strategy to eliminate schistosomiasis from this region.

  2. Monitoring schistosomiasis risk in East China over space and time using a Bayesian hierarchical modeling approach

    PubMed Central

    Hu, Yi; Ward, Michael P.; Xia, Congcong; Li, Rui; Sun, Liqian; Lynn, Henry; Gao, Fenghua; Wang, Qizhi; Zhang, Shiqing; Xiong, Chenglong; Zhang, Zhijie; Jiang, Qingwu

    2016-01-01

    Schistosomiasis remains a major public health problem and causes substantial economic impact in east China, particularly along the Yangtze River Basin. Disease forecasting and surveillance can assist in the development and implementation of more effective intervention measures to control disease. In this study, we applied a Bayesian hierarchical spatio-temporal model to describe trends in schistosomiasis risk in Anhui Province, China, using annual parasitological and environmental data for the period 1997–2010. A computationally efficient approach–Integrated Nested Laplace Approximation–was used for model inference. A zero-inflated, negative binomial model best described the spatio-temporal dynamics of schistosomiasis risk. It predicted that the disease risk would generally be low and stable except for some specific, local areas during the period 2011–2014. High-risk counties were identified in the forecasting maps: three in which the risk remained high, and two in which risk would become high. The results indicated that schistosomiasis risk has been reduced to consistently low levels throughout much of this region of China; however, some counties were identified in which progress in schistosomiasis control was less than satisfactory. Whilst maintaining overall control, specific interventions in the future should focus on these refractive counties as part of a strategy to eliminate schistosomiasis from this region. PMID:27053447

  3. Crustal structure of China and adjacent areas: a final report of the detailed compilation of data and results

    SciTech Connect

    Mooney, W D

    1998-06-04

    In geophysical terms, China is a ''data rich'' country. However it is often very difficult for Western scientists to access the available information or identify individuals responsible for program development. The USGS has largely bypassed this bottleneck by virtue of more than two decades of collaborative research based on an official Protocol Agreement.

  4. Geochemical dynamics of iodine in marginal seas: the southern East China Sea

    NASA Astrophysics Data System (ADS)

    Wong, George T. F.; Zhang, Ling-Su

    2003-03-01

    The distributions of iodate and iodide were determined in a transect across the southern East China Sea Shelf, the upwelling center at the outer shelf-upper slope, the adjoining Kuroshio to the Okinawa Trough. In the surface waters, the variations in the concentrations of iodate and iodide among the surface waters masses, namely, the Coastal Water, the Taiwan Current Warm Water and the Kuroshio Surface Water, were relatively small. The composition of the upwelling Kuroshio Subsurface Water was distinctly different and it could be readily distinguished from the surface water masses by its elevated concentration of iodate, depressed concentration of iodide, and the resulting elevated concentration ratio of iodate to iodide. In contrast, since the variations in salinity and temperature in the surface water masses and the upwelling water were less systematic, neither salinity nor temperature could be used effectively for distinguishing these two types of water from each other. Thus, the iodine system was a complementary, or even a superior, tracer for the upwelling water. In the subsurface, the upwelling water was depicted as a dome of cold, nitrate-rich, iodate-rich and iodide-poor water, with molar ratios of iodate to iodide exceeding 10 that extended from the outer shelf-upper slope to the middle shelf. The influence of the Coastal Water was manifested as a tongue of fresher, iodide-rich and iodate-poor surface water, with molar ratios of iodate to iodide of <2.5 that extended from the inner shelf into the middle shelf. The oligotrophic Kuroshio Surface Water was also iodide-rich and iodate-poor. A box model calculation revealed that iodate was imported into the East China Sea Shelf system by frontal exchanges with the adjoining Kuroshio and upwelling at the shelf edge. Within the Shelf system, iodate was consumed and iodide was produced. As a result, during frontal exchanges between the Shelf system and the Kuroshio, there was also a net export of iodide from the

  5. Historical reconstruction of organic carbon decay and preservation in sediments on the East China Sea shelf

    NASA Astrophysics Data System (ADS)

    Li, Xinxin; Bianchi, Thomas S.; Allison, Mead A.; Chapman, Piers; Yang, Guipeng

    2013-07-01

    cores were collected from the East China Sea inner shelf in 2010 to study the decay and preservation of organic carbon (OC). The highest sediment mass accumulation rate (0.61 ± 0.20 g cm-2 yr-1), derived from 210Pb, was found near the river mouth and decreased alongshore to the south (0.17 ± 0.004 g cm-2 yr-1), and in an offshore direction (0.31 ± 0.08 g cm-2 yr-1). Average total OC content was higher at inner shelf stations (0.52%) than those offshore (0.38%). The δ13C was more depleted at nearshore (-23.49‰ to -21.97‰) than offshore (-22.49‰ to -21.60‰) stations. Principal component analysis indicated that terrestrial OC, as indicated by lignin-phenols (Λ8) values, was preserved in sediment closer to the coast (0.22-0.44), while offshore sediment was more composed of lignin-poor (0.12-0.24) degraded OC that was likely hydrodynamically sorted. Marine-derived OC, as indicated by plant pigments, was significantly more abundant in the sediment mixed layer than the underlying accumulation layer. Historical flooding events were detected in Λ8 profiles in two of the six cores located at midshelf stations. Despite the magnitude of the 2010 flood in East China, we did not see any signature of this event with the chemical biomarker in these two cores. This may suggest that reduced sediment loading due to recent dam construction may have greatly decoupled river inputs with sediment loading to shelf sediment. The total OC standing stock since 1900 was approximately 1.62 ± 1.15 kg C m-2, about one tenth of all the middle and lower lakes in the Changjiang catchment basin. This work further supports the need for more research to better understand how the reduced inputs of fluvial input of sediments from Chinese rivers (due to river diversions and dams) affect carbon cycling in the East China Sea.

  6. Summer and winter living coccolithophores in the Yellow Sea and the East China Sea

    NASA Astrophysics Data System (ADS)

    Gu, X. Y.; Feng, Y. Y.; Jin, S. F.; Jiang, W. S.; Jin, H. Y.; Chen, J. F.; Sun, J.

    2013-05-01

    To date, very little information on living coccolithophores species composition and distribution, especially the vertical profile has been reported around the world. This paper tries to fill this gap by descripting on living coccolithophores (LCs) distribution in the Yellow Sea and the East China Sea in summer and winter time in detail, and its relationship among enviromental factors by canonical correspondence analysis (CCA). We carried out the investigations on LC distribution in the Yellow Sea and the East China Sea in July and December 2011. 210 samples from different depths were collected from 44 stations in summer and 217 samples were collected from 45 stations in winter. Totally 20 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1000 × magnification. The dominant species of the two seasons were Gephyrocapsa oceanica, Emiliania huxleyi, Helicosphaera carteri, and Algirosphaera robusta. In summer the abundance of cells and coccoliths ranged 0 ~ 176.40 cells mL-1, and 0 ~ 2144.98 coccoliths mL-1, with the average values of 8.45 cells mL-1, and 265.42 coccoliths mL-1, respectively. And in winter the abundance of cells and coccoliths ranged 0 ~ 71.66 cells mL-1, and 0 ~ 4698.99 coccoliths mL-1, with the average values of 13.91 cells mL-1 and 872.56 coccoliths mL-1 respectively. In summer the LCs in surface layer were mainly observed on the coastal belt and southern part of the survey area. The highest abundance was found at the bloom station. In winter the LCs in surface layer had high value in the continental shelf area of section P. The comparison among section A, section F, section P and section E indicated lower species diversity and less abundance in the Yellow Sea than those of the East China Sea in both seasons. Temperature and the nitrate concentration may be the major environmental factors controlling the distribution and species composition of LCs in the studying area based on CCA.

  7. Spatial and seasonal patterns of ichthyoplankton assemblages in the Haizhou Bay and its adjacent waters of China

    NASA Astrophysics Data System (ADS)

    Li, Zengguang; Ye, Zhenjiang; Wan, Rong

    2015-12-01

    Surveys were conducted in five voyages in Haizhou Bay and its adjacent coastal area from March to December 2011 during full moon spring tides. The ichthyoplankton assemblages and the environmental factors that affect their spatial and seasonal patterns were determined. Totally 35 and 12 fish egg and larvae taxa were identified, respectively. Over the past several decades, the egg and larval species composition has significantly changed in Haizhou Bay and its adjacent waters, most likely corresponding with the alteration of fishery resources, which are strongly affected by anthropogenic activities and climate change. The Bray-Curtis dissimilarity index identified four assemblages: near-shore bay assemblage, middle bay assemblage and two closely related assemblages (near-shore/middle bay assemblage and middle/edge of bay assemblage). The primary species of each assemblage principally reflected the spawning strategies of adult fish. The near-shore bay assemblage generally occurred in near-shore bay, with depths measuring <20 m, and the middle bay assemblage generally occurred in the middle of bay, with depths measuring 20 to 40 m. Spatial and seasonal variations in ichthyoplankton in each assemblage were determined by interactions between biological behavioral traits and oceanographic features, particularly the variation of local conditions within the constraint of a general reproductive strategy. The results of Spearman's rank correlation analysis indicated that both fish egg and larval abundance were positively correlated with depth, which is critical to the oceanographic features in Haizhou Bay.

  8. Urban Community Development and Private Education Dilemma: Based on a Field Study of a City in East China

    ERIC Educational Resources Information Center

    Qian, Li; Anlei, Jing

    2014-01-01

    Urbanization is an issue of universal concern today distinctly affecting the supply, content, and orientation of education. Based on a field study in a city in East China, the article argues that rural-urban migration in the process of urbanization created private sectors in education enterprises that were in sync with the urban community…

  9. High-Resolution Hydrographic Surveys Near the Shelfbreak in the East China Sea: Joint Studies with National Taiwan University

    DTIC Science & Technology

    2012-08-23

    the high-resolution hydrographic data into their model and producing ocean circulation forecasts including uncertainty forecasts. During the field...SUBJECT TERMS East China Sea, High-Resolution Hydrographic Surveys, Shelfbreak, Ocean Circulation Forecasts, Typhoon Morakot 16. SECURITY...model forecasts of the ocean circulation . This work involved close collaboration with Dr. Sen Jan of National Taiwan University for overall planning

  10. Clay mineralogical and geochemical proxies of the East Asian summer monsoon evolution in the South China Sea during Late Quaternary.

    PubMed

    Chen, Quan; Liu, Zhifei; Kissel, Catherine

    2017-02-08

    The East Asian summer monsoon controls the climatic regime of an extended region through temperature and precipitation changes. As the East Asian summer monsoon is primarily driven by the northern hemisphere summer insolation, such meteorological variables are expected to significantly change on the orbital timescale, influencing the composition of terrestrial sediments in terms of both mineralogy and geochemistry. Here we present clay mineralogy and major element composition of Core MD12-3432 retrieved from the northern South China Sea, and we investigate their relationship with the East Asian summer monsoon evolution over the last 400 ka. The variability of smectite/(illite + chlorite) ratio presents a predominant precession periodicity, synchronous with the northern hemisphere summer insolation changes and therefore with that of the East Asian summer monsoon. Variations in K2O/Al2O3 are characterized by eccentricity cycles, increasing during interglacials when the East Asian summer monsoon is enhanced. Based on the knowledge of sediment provenances, we suggest that these two proxies in the South China Sea are linked to the East Asian summer monsoon evolution with different mechanisms, which are (1) contemporaneous chemical weathering intensity in Luzon for smectite/(illite + chlorite) ratio and (2) river denudation intensity for K2O/Al2O3 ratio of bulk sediment.

  11. Clay mineralogical and geochemical proxies of the East Asian summer monsoon evolution in the South China Sea during Late Quaternary

    NASA Astrophysics Data System (ADS)

    Chen, Quan; Liu, Zhifei; Kissel, Catherine

    2017-02-01

    The East Asian summer monsoon controls the climatic regime of an extended region through temperature and precipitation changes. As the East Asian summer monsoon is primarily driven by the northern hemisphere summer insolation, such meteorological variables are expected to significantly change on the orbital timescale, influencing the composition of terrestrial sediments in terms of both mineralogy and geochemistry. Here we present clay mineralogy and major element composition of Core MD12-3432 retrieved from the northern South China Sea, and we investigate their relationship with the East Asian summer monsoon evolution over the last 400 ka. The variability of smectite/(illite + chlorite) ratio presents a predominant precession periodicity, synchronous with the northern hemisphere summer insolation changes and therefore with that of the East Asian summer monsoon. Variations in K2O/Al2O3 are characterized by eccentricity cycles, increasing during interglacials when the East Asian summer monsoon is enhanced. Based on the knowledge of sediment provenances, we suggest that these two proxies in the South China Sea are linked to the East Asian summer monsoon evolution with different mechanisms, which are (1) contemporaneous chemical weathering intensity in Luzon for smectite/(illite + chlorite) ratio and (2) river denudation intensity for K2O/Al2O3 ratio of bulk sediment.

  12. Clay mineralogical and geochemical proxies of the East Asian summer monsoon evolution in the South China Sea during Late Quaternary

    PubMed Central

    Chen, Quan; Liu, Zhifei; Kissel, Catherine

    2017-01-01

    The East Asian summer monsoon controls the climatic regime of an extended region through temperature and precipitation changes. As the East Asian summer monsoon is primarily driven by the northern hemisphere summer insolation, such meteorological variables are expected to significantly change on the orbital timescale, influencing the composition of terrestrial sediments in terms of both mineralogy and geochemistry. Here we present clay mineralogy and major element composition of Core MD12-3432 retrieved from the northern South China Sea, and we investigate their relationship with the East Asian summer monsoon evolution over the last 400 ka. The variability of smectite/(illite + chlorite) ratio presents a predominant precession periodicity, synchronous with the northern hemisphere summer insolation changes and therefore with that of the East Asian summer monsoon. Variations in K2O/Al2O3 are characterized by eccentricity cycles, increasing during interglacials when the East Asian summer monsoon is enhanced. Based on the knowledge of sediment provenances, we suggest that these two proxies in the South China Sea are linked to the East Asian summer monsoon evolution with different mechanisms, which are (1) contemporaneous chemical weathering intensity in Luzon for smectite/(illite + chlorite) ratio and (2) river denudation intensity for K2O/Al2O3 ratio of bulk sediment. PMID:28176842

  13. The influences of East Asian Monsoon on summer precipitation in Northeast China

    NASA Astrophysics Data System (ADS)

    Sun, Li; Shen, Baizhu; Sui, Bo; Huang, Bohua

    2017-03-01

    A unique dataset of 53-year (1961-2013) rainfall measurements from 104 stations uniformly distributed in the Northeast China, combined with the observation-based NCEP/NCAR atmospheric reanalysis, is used to analyze the precipitation anomalies in Northeast China during late boreal summer (July-August) and their relationship with the anomalous moisture transport associated with the fluctuations of the East Asian Summer Monsoon (EASM) circulation. Based on this analysis, a new EASM influence index ( I EASM ) is proposed to quantify the EASM effects on the Northeast China summer precipitation. The relationship between the IEASM variations and patterns of the anomalous regional atmospheric circulation is demonstrated. The characteristics of several precursors that lead to the major fluctuations of the I EASM index are also explored. The results show that the EASM influence index is closely linked to the anomalous rainfall in Northeast China and can be used as a major factor to measure the physical processes that affect the regional dry and wet conditions. The I EASM index responds to the large-scale anomalies of the atmospheric circulation sensitively. Specifically, the high I EASM values are associated with the intensified Mongolia cyclone, blocking developing near the Ural Mountains and a northwestward shift of subtropical high over the western Pacific. The low I EASM values are associated with a reversed pattern of these features. The I EASM anomalous fluctuation has some precursors. A major high (low) index during the summer is likely preceded with the pattern of the sea surface temperature anomalies of an El Niño (La Niña) event in the Pacific from the previous early fall to early winter.

  14. The influences of East Asian Monsoon on summer precipitation in Northeast China

    NASA Astrophysics Data System (ADS)

    Sun, Li; Shen, Baizhu; Sui, Bo; Huang, Bohua

    2016-05-01

    A unique dataset of 53-year (1961-2013) rainfall measurements from 104 stations uniformly distributed in the Northeast China, combined with the observation-based NCEP/NCAR atmospheric reanalysis, is used to analyze the precipitation anomalies in Northeast China during late boreal summer (July-August) and their relationship with the anomalous moisture transport associated with the fluctuations of the East Asian Summer Monsoon (EASM) circulation. Based on this analysis, a new EASM influence index (I EASM ) is proposed to quantify the EASM effects on the Northeast China summer precipitation. The relationship between the IEASM variations and patterns of the anomalous regional atmospheric circulation is demonstrated. The characteristics of several precursors that lead to the major fluctuations of the I EASM index are also explored. The results show that the EASM influence index is closely linked to the anomalous rainfall in Northeast China and can be used as a major factor to measure the physical processes that affect the regional dry and wet conditions. The I EASM index responds to the large-scale anomalies of the atmospheric circulation sensitively. Specifically, the high I EASM values are associated with the intensified Mongolia cyclone, blocking developing near the Ural Mountains and a northwestward shift of subtropical high over the western Pacific. The low I EASM values are associated with a reversed pattern of these features. The I EASM anomalous fluctuation has some precursors. A major high (low) index during the summer is likely preceded with the pattern of the sea surface temperature anomalies of an El Niño (La Niña) event in the Pacific from the previous early fall to early winter.

  15. Effects of urban land-use change in East China on the East Asian summer monsoon based on the CAM5.1 model

    NASA Astrophysics Data System (ADS)

    Ma, Hongyun; Jiang, Zhihong; Song, Jie; Dai, Aiguo; Yang, Xiuqun; Huo, Fei

    2016-05-01

    The effects of urban land-use change in East China on the East Asian summer monsoon (EASM) are investigated using a Community Atmosphere Model Version 5.1. The results show that the urban land-use change in East China causes spatially-varying changes in surface net radiation and heat fluxes, atmospheric circulation, and water budgets. It results in significant surface warming (cooling) and precipitation decrease (increase) in a large region north (south) of 30°N. Urban expansion agglomerated in (29°-41°N, 110°-122°E) alters the surface energy budget and warms the surface, resulting in strengthened southwesterly airflow south of 25°N and increased convergence below the mid-troposphere between 20° and 30°N. A concomitant northward downdraft associated with the increased convection generates an anomalous high pressure north of 30°N. Meanwhile, the downdraft not only produces adiabatic warming but also inhibits the dynamic condition for precipitation formation. The anomalous high pressure formed in North China prevents the southwesterly airflow from advancing northward, leading to increase the convergence and precipitation in South China. These changes reduce the meridional temperature gradient in the mid-lower troposphere and weaken the westerly airflow near 30°N. In addition, horizontal transport of vorticity north of 35°N weakens significantly, which leads to an anomalous barotropic structure of anticyclonic there. As a result, the anomalous anticyclonic circulation and descent north of 30°N are strengthened. At the same time, the anomalous cyclonic circulation and ascent south of 30°N are enhanced. These process induced by the thermal state changes due to urbanization weakens the EASM.

  16. Nitrogen deposition fuels harmful algal blooms in the East China Sea

    NASA Astrophysics Data System (ADS)

    Mackey, K. R.; Kavanaugh, M.; Chien, C. T.; Chen, Y.; Glover, D. M.; Paytan, A.

    2015-12-01

    Chinese marginal seas support vast fisheries and vital economies, but their productivity is threatened by eutrophication and increasing harmful algal blooms (HABs). Here we provide direct experimental evidence that aerosol enrichment shifts seawater chemistry by increasing the ratio of N to phosphorus (N:P) and supports the growth of bloom-forming phytoplankton in the East China Sea. We use a combination of field-based aerosol addition incubation experiments, along with ocean color data on blooms dominated by different taxa to show that HAB forming dinoflagellates are particularly responsive to aerosol inputs. Moreover, we show that the effect of N deposition is strongest in offshore waters further from the Yangtze River outflow, consistent with the large anthropogenic flux of N from this source. This study shows the potential for aerosols to control N:P ratios in offshore waters and to shape the phytoplankton community, contributing to the success of bloom-forming organisms.

  17. A new species of free-living marine nematode (Nematoda: Chromadoridae) from the East China Sea.

    PubMed

    Chunming, Wang; Liguo, An; Yong, Huang

    2015-04-15

    A new species of free-living marine nematodes, Ptycholaimellus longibulbus sp. nov., is described from the East China Sea. Ptycholaimellus longibulbus sp. nov. is characterized by having body length of about 1100-1400 μm, cephalic seta 9 µm long (half a head diameter), a relatively long double posterior pharyngeal bulb occupying 44-49% of pharyngeal length, a voluminous ventral gland with a large ampulla, cuticle with transverse rows of punctations and lateral differentiation with two longitudinal rows of thick dots, relatively long spicules 45-55 μm long, an arcuate gubernaculum 25 µm long, and a conico-cylindrical tail with a distinct long finger-like spinneret. A key to species of Ptycholaimellus is given.

  18. Pseudolella major sp. nov. (Axonolaimidae, Nematoda) from the intertidal zone of the East China Sea

    NASA Astrophysics Data System (ADS)

    Wang, Chunming; Huang, Yong

    2016-03-01

    A new species of free-living nematode, Pseudolella major sp. nov. is described from the intertidal mudflats of Ximen Island in the East China Sea. Pseudolella major sp. nov. is characterized as follows: body length ~1 300 μm; short cephalic setae, 2-3 μm long; amphidial fovea loop-shaped with elongated ventral branch; ventral branch 50-60 μm long and extending past the base of buccal cavity; buccal cavity cylindrical with arching or spherical base; three heavy outwardly-curving odontia with blunt tips located at anterior of buccal cavity; pharynx short with posterior bulb; ventral gland cell elongate oval-shaped, located posterior to pharyngo-intestinal junction; excretory pore situated at the level of the middle of buccal cavity; tail conical to cylindrical; spicules arched, with double-cephalate proximal end; gubernaculum with a strong dorsal caudal apophysis.

  19. Oncholaimus zhangi sp. nov. (Oncholaimidae, Nematoda) from the intertidal zone of the East China Sea

    NASA Astrophysics Data System (ADS)

    Gao, Qun; Huang, Yong

    2016-10-01

    A new species of free-living marine nematode is described from intertidal sediment of the East China Sea. The new species belongs to the Oncholaimidae family. Oncholaimus zhangi sp. nov. is characterized by males having a large ventral swelling situated just posterior to the middle of the tail, no precloacal papilla, and a row of 6-7 ventral genital setae. The tails of both males and females are similar, being conico-cylindrical in shape. The new species is distinguished from other closely related species by the presence of a prominent ventral swelling at the tail of males and a similar tail shape in both sexes. About 110 valid species in this genus have been recorded to date.

  20. Investigation of atmospheric aerosols and gases at an East China Station. Technical memo

    SciTech Connect

    Parungo, F.; Nagamoto, C.; Kopcewicz, B.; Li, X.; Yang, D.

    1993-04-01

    From August to October of 1991, when the West Pacific Exploratory Mission (PEM-west) airborne expedition was conducted, ground-level measurements of gases and aerosols were carried out at Lin-an station near the east coast of China. Meteorological parameters such as temperature, pressure, humidity, solar radiation, wind direction, and wind speed were recorded continuously. Concentrations of SO[sub 2], NO[sub 2], O[sub 3], and black carbon were monitored in situ intermittently. Aerosol samples were collected and later analyzed in laboratories. A transmission electron microscope was used to analyze particle concentration, morphology, and size distribution. Elemental compositions of aerosol samples, collected on filters, were determined with an neutron activation analyzer and with a proton induced x-ray energy spectrometer. The water soluble portions of the aerosols were analyzed by ion chromatography.

  1. Free polyamine content during algal bloom succession in the East China Sea in spring 2010

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Zhao, Weihong; Li, Caiyan; Miao, Hui

    2017-01-01

    We measured the concentrations and distribution of major polyamines (spermine, putrescine and spermidine) in seawater during successive spring algal blooms in an area of frequent harmful blooms in the East China Sea. Spermine, putrescine, and spermidine concentrations were analyzed by high performance liquid chromatography and ranged from 1-64, 7-81, and 0-19 nmol/L. Spermine was present at the highest concentrations, followed by putrescine and spermidine. In late April, when a diatom bloom dominated by Skeletonema costatum dispersed, polyamine concentrations increased, presumably as a result of diatom decomposition. In early May, when a dinoflagellate bloom dominated by Prorocentrum donghaiense occurred, the polyamine concentration decreased from the level seen in late April. The abundant polyamines that decomposed and were released during the diatom bloom in late April may have promoted the growth of P. donghaiense, resulting in its dominance.

  2. Responses of phytoplankton community to the input of different aerosols in the East China Sea

    NASA Astrophysics Data System (ADS)

    Meng, X.; Chen, Y.; Wang, B.; Ma, Q. W.; Wang, F. J.

    2016-07-01

    Atmospheric deposition can affect marine phytoplankton by supplying macronutrients and trace elements. We conducted mesocosm experiments by adding aerosols with different composition (dominated by mineral dust, biomass burning and high Cu, and secondary aerosol, respectively) to the surface seawater of the East China Sea. Chlorophyll a concentrations were found to be the highest and lowest after adding aerosols containing the highest Fe and dissolved inorganic nitrogen (DIN), respectively. The relative abundance of Haptophyceae increased significantly after adding mineral dust, whereas diatom, Dinophyceae and Cryptophyceae reached the maximum accompanied with the highest DIN. Our results suggest that Fe may be more important than DIN in promoting primary productivity in the sampled seawater. The input of mineral dust and anthropogenic aerosols may result in distinct changes of phytoplankton community structure.

  3. Practices, perceptions, and implications of fertilizer use in East-Central China.

    PubMed

    Yang, Xiaoying; Fang, Shubo

    2015-11-01

    Face-to-face interviews (n = 553) were conducted in five counties in East-Central China to study farmers' fertilizer application behaviors, decision-making processes, attitudes towards adopting better fertilizer application technologies, and environmental consciousness. The survey results revealed widespread fertilizer misapplication and highly variable application behaviors in the study regions. The lack of scientific knowledge on fertilizers and the absence of guidance from agricultural extension services have forced the farmers to rely on personal judgment and advice from fertilizer dealers and friends to make decisions in fertilizer application. Overall, farmers have been idiosyncratic in fertilizer application with limited adoption of better fertilizer application technologies. There are great potentials for reducing pollutant load from agricultural runoff through promoting scientific fertilizer application in the regions. However, farmers' diverse preferences over agricultural extension programs necessitate an integrated approach emphasizing farmer involvement throughout the development of such programs for promoting better fertilizer application practices.

  4. Increased zooplankton PAH concentrations across hydrographic fronts in the East China Sea.

    PubMed

    Hung, Chin-Chang; Ko, Fung-Chi; Gong, Gwo-Ching; Chen, Kuo-Shu; Wu, Jian-Ming; Chiang, Hsin-Lun; Peng, Sen-Chueh; Santschi, Peter H

    2014-06-15

    The Changjiang has transported large quantities of polycyclic aromatic hydrocarbons (PAHs) to the East China Sea (ECS), but information of these pollutants in zooplankton is limited. To understand PAHs pollution in zooplankton in the ECS, total concentrations of PAHs in zooplankton from surface waters were measured. Values of PAHs ranged from 2 to 3500 ng m(-3) in the ECS, with highest PAHs levels located at the salinity front between the Changjiang Diluted Water (CDW) and the mid-shelf waters. In contrast, concentrations of zooplankton PAHs in the mid-shelf and outer-shelf waters were significantly lower (2-23 ng m(-3)) than those in the CDW. These results demonstrate that PAHs are conspicuously accumulated in zooplankton at the salinity front between the CDW and the mid-shelf waters. These higher levels of PAHs in zooplankton at the salinity front may be further biomagnified in marine organisms of higher trophic levels through their feeding activities.

  5. Prevalence and Molecular Characterization of Intestinal Trichomonads in Pet Dogs in East China

    PubMed Central

    Li, Wen-Chao; Wang, Kai; Zhang, Wei; Wu, Jingjing; Gu, You-Fang; Zhang, Xi-Chen

    2016-01-01

    The trichomonad species Tritrichomonas foetus and Pentatrichomonas hominis were recently detected in the feces of dogs with diarrhea. However, little information is available on the prevalence and pathogenicity of these parasites in the canine population. Therefore, the aim of this study was to determine the prevalence and molecular characterization of trichomonads infecting pet dogs in Anhui and Zhejiang provinces, east China. In total, 315 pet dogs, with or without diarrhea, from 7 pet hospitals were included in this epidemiological survey. Microscopy and PCR detected P. hominis in 19.7% (62/315) and 31.4% (99/315) of fecal samples, respectively. T. foetus infection was detected in 0% (0/315) of samples with microscopy and in 0.6% (2/315) with PCR. The prevalence of P. hominis was significantly higher in young dogs (≤12 months) than in adult dogs (>12 months), and was significantly higher in diarrheic dogs (50.6%) than in non-diarrheic dogs (24.3%; P<0.05). Infection with T. foetus did not correlate with any risk factors evaluated in this study. A sequence analysis of the P. hominis PCR products showed minor allelic variations between our sequences and those of P. hominis strains from other hosts in different parts of the world. Type CC1 was the most common strain in dogs in east China. The internal transcribed spacer 1 (ITS1)-5.8S rRNA gene sequences from the 2 T. foetus isolates detected in this study displayed 100% identity and were homologous to the sequences of other strains isolated from domestic cats in other countries. PMID:28095654

  6. Five Sarsiellidae ostracods (Crustacea: Myodocopida) from the South Coast of Korea (East China Sea).

    PubMed

    Karanovic, Ivana; Soh, Ho-Young

    2015-04-17

    The East China Sea is part of the Warm Temperate Northwest Pacific zoogeographic province and, as such, has a high biodiversity and many tropical and subtropical biotic elements. Nevertheless, many invertebrate groups from this area remain poorly studied. Ostracods are one of them, especially those belonging to the subclass Myodocopa. In this paper we provide the first data on a diverse myodocopid family, Sarsiellidae, not only for the East China Sea, but also for Korea. Five species are reported in this paper from three Korean islands (Jeju, Chuja, and Maemul), and they are only a part of the ostracods collected during this study, indicating a high diversity of the group in this region. Three new species, Eurypylus koreanus sp. nov., Eusarsiella hanguk sp. nov., and Sarsiella nereis sp. nov., clearly stand apart from their respective congeners, mostly by prominent shell characters but also by details of the soft part morphology. Their affinity though clearly indicates a close connection of the region with the more southern zoogeographical realms, especially Central Indo Pacific and partly Temperate Australasia. Two species previously known from Japan (north part of the Sea of Japan and southeastern part of the Pacific Coast of Japan), Sarsiella japonica Hiruta, 1977 and S. misakiensis Kajiyama, 1912, are redescribed. Based on 11 newly obtained COI sequences we construct a preliminary phylogenetic tree, which supports previous hypotheses based on the morphological data, that Eusarsiella Cohen & Kornicker, 1975 is a polyphyletic taxon. With the maps of species distribution provided for each of the three genera, we give an overview of their current zoogeography, and clearly indicate areas that have no data, mostly due to the lack of investigation.

  7. Characteristics of Infective Endocarditis in a Tertiary Hospital in East China

    PubMed Central

    Xu, Huimin; Cai, Siyu

    2016-01-01

    The epidemiology, clinical presentation, and treatment of infective endocarditis (IE) has significantly changed over the past few years in developed countries. However, relevant data from developing countries are different and remain scarce. The objective of this study was to evaluate the clinical presentations, treatment and outcomes of IE patients in a tertiary hospital in East China over an 8-year period. This was a retrospective observational study of consecutive cases of definite or possible IE as per the modified Duke criteria between January 2008 and December 2015. A total of 135 definite and 39 probable IE cases were identified. The mean age was 47.8 ± 15.7 years, with a male preponderance (1.9: 1). Degenerative valve disease accounted for 30.5% cases of IE, followed by congenital heart disease (29.9%) and rheumatic heart disease (14.9%). Native cardiac valves were present in 93.7% of the IE patients. Echocardiography and blood culture were performed in all patients, of whom 55.2% were found to have large vegetations (≥10 mm) and the positive rate of blood culture was 60.3%. Streptococcus remained the chief causative agent that was identified in 61.9% of culture-positive patients. Glycopeptide antibacterials and cephalosporins were the most frequently used antimicrobial drugs for IE therapy. Seventy-six (43.7%) of the IE patients were surgically treated. The mortality rate during hospital stay was 10.9%. Our data reflected clinical and microbiological profile, and treatment of IE in a tertiary hospital located in the East China. PMID:27861628

  8. [Relationships between population characters of Undinula vulgaris (Copepoda) and environment in the East China Sea].

    PubMed

    Xu, Zhaoli

    2006-01-01

    Based on the data of four seasonal oceanographic censuses in 1997 approximately 2000 in the East China Sea (23 degrees 30' approximately 33 degrees N, 118 degrees 30' approximately 128 degrees E), this paper discussed the relationships between the ecological characters of natural Undinula vulgaris population and its environment in the Sea, with the data of 1979 approximately 1980 compared. The results showed that there was a very clear seasonal change of the dominance, abundance, and occurrence frequency of U. vulgaris, i.e.,autumn (0.09, 556 ind x 100 m(-3), 93.69%) >summer (0.03, 86 ind x 100 m(-3), 68.49%) >winter (0.02, 42 ind x 100 m(-3), 53.85%) >spring (0.01, 16 ind x 100 m(-3), 34.35%). As a dominant species of pelagic copepods in the Sea, U. vulgaris showed its predominance mainly in autumn. The percentage of U. vulgaris in the total abundance of pelagic copepods was 2.31% in spring, 4.80% in summer, 3.80% in winter, and 9.90% in autumn, while its occurrence frequency was the highest in autumn and the lowest in winter. Comparing the results of this study with the data of 1979 approximately 1980, the importance of U. vulgaris in pelagic copepods in the Sea was decreased in spring, summer and autumn, but increased in winter, which might be related with the global warming in winter. The main environmental factors affecting U. vulgaris abundance were the bottom water factors that closely related with the warm current in the ocean. Because of its sensibility to low temperature and coastal water mass, U. vulgaris could be used as a good indicator of warm current, and, as a good food for fishes, this species plays an important role in marine fishing in the middle-south part of the East China Sea.

  9. Spatial variations of the Kuroshio nutrient stream from the East China Sea to South of Japan

    NASA Astrophysics Data System (ADS)

    Zhu, Xiao-Hua; Guo, Xinyu; Long, Yu; Li, Bo

    2013-04-01

    Based on velocity calculated from hydrographic data obtained from 39 cruises during from 2000 to 2009 and nitrate concentration data observed from 1964 to 2011, we calculated nitrate flux (the product of velocity and nitrate concentration) and nitrate transport (integration of flux over a section) through 5 sections along the Kuroshio path from the East China Sea (Sections PN and TK) to south of Japan (Sections ASUKA and 137E). In addition, Section OK east of the Ryukyu Islands was also examined. The nitrate flux showed a subsurface maximum core with a value of 9, 10, 6, 11 and 11 mol/m^2/s at Sections PN, TK, OK, ASUKA, 137E, respectively. The depth of subsurface maximum core changes at five sections and was about 400, 500, 800, 500, and 400 m at Sections PN, TK, OK, ASUKA, 137E, respectively. The eastward nitrate transport was 171, 167, 351, 942, 1444 k mol/s at Sections PN, TK, OK, ASUKA, 137E, respectively. The difference between nitrate transport through Section ASUKA and the sum of transports through Sections TK and OK, as well as the difference of nitrate transport between Sections ASUKA and 137E, suggest that the Kuroshio recirculation south of Shikoku can significantly intensify the eastward nitrate transport by the Kuroshio and therefore play an important role in the nitrate transport in the Kuroshio region.

  10. Spatial variations in the Kuroshio nutrient transport from the East China Sea to south of Japan

    NASA Astrophysics Data System (ADS)

    Guo, X. Y.; Zhu, X.-H.; Long, Y.; Huang, D. J.

    2013-10-01

    Based on absolute geostrophic velocity, which was calculated using repeated hydrographic data of 39 cruises from 2000 to 2009 and nitrate concentrations measured in the same areas from 1964 to 2009, we obtained the temporally averaged nitrate flux (the product of velocity and nitrate concentration) and nitrate transport (integration of flux over one section) of four sections across the Kuroshio from the East China Sea (sections PN and TK) to an area south of Japan (sections ASUKA and 137E). In addition, we examined section OK east of the Ryukyu Islands in order to understand how the Ryukyu Current contributes to the transport of nutrients by the Kuroshio south of Japan. The mean nitrate flux shows a subsurface maximum core with values of 9.6, 10.6, 11.2, 10.5, and 5.7 mol m-2 s-1 at sections PN, TK, ASUKA, 137E, and OK, respectively. The depth of the subsurface maximum core changes among these five sections and is approximately 400, 500, 500, 400, and 800 m at sections PN, TK, ASUKA, 137E, and OK, respectively. The mean downstream nitrate transport is 204.8, 165.8, 879.3, 1230.4, and 338.6 kmol s-1 at sections PN, TK, ASUKA, 137E, and OK, respectively. The transport of nutrients in these sections suggests the presence of the Kuroshio nutrient stream from its upstream to downstream regions. The deep current structure of the Ryukyu Current (section OK) contributes to the same order of nitrate transport as does the Kuroshio from the East China Sea (section TK) to the area south of Japan; however, the former only has one-fifth the volume transport of the latter. A budget calculation suggests that the downstream increase of transported nitrate along the Kuroshio is mainly caused by the recirculation of nitrate into the Kuroshio. This conclusion, however, depends on water depth. In the upper layers (< 26.5σθ), the downstream change of nitrate concentration along the Kuroshio and that from the recirculation of nitrate has a significant contribution to the downstream

  11. Data Fusion of SST from HY-2A Satellite Radiometer in China Sea and its Adjacent Waters

    NASA Astrophysics Data System (ADS)

    Li, Xiaohui; Yang, Jingsong; Zheng, Gang; Han, Guoqi; Ren, Lin; Wang, Juan

    2016-08-01

    This paper focuses on using data fusion method to solve the problem that the global sea is not seamlessly covered by the along-track sea surface temperature (SST) data of scanning microwave radiometer on board Haiyang-2A (HY-2A), which is the first ocean dynamic environment satellite of China launched on 16th August 2011. The procedure includes following steps. Firstly, the HY-2A SST data within 200 km of the coastline were identified and removed, the outliers of the HY-2A SST data and the background SST data were also identified and removed. Secondly, the HY-2A SST data were gridded, filtered and corrected. The background SST data were only filtered. Finally, the HY-2A SST data were merged into background SST data by the inverse distance weighted method. Next, the above procedure was tested in the ocean area on the southeast of China. The global 1-km sea surface temperature (G1SST) data were used as the reference data. The results of the procedure with and without the second step were made comparisons, and the results implied that the application of median filter and third-order polynomial curve fitting in the second step could help to improve performance of the merged SST data. The along-track SST data of HY-2A can be merged into OSTIA SST data successfully by the above procedure, and the gaps between tracks were filled up.

  12. Classification of typical summer rainfall patterns in the East China monsoon region and their association with the East Asian summer monsoon

    NASA Astrophysics Data System (ADS)

    Yang, Liu; Zhao, Junhu; Feng, Guolin

    2016-06-01

    In this study, the summer rainfall patterns in the East China monsoon region during 1951-2015 were objectively classified into four typical categories: the northern China rainfall pattern (NCP), the intermediate rainfall pattern (IRP), the Yangtze River rainfall pattern (YRP), and the South China rainfall pattern (SCP). The periods of the four patterns show significant decadal characteristics. The NCP occurred mainly between the late 1950s and the early 1980s, and the IRP in the late 1950s to the early 1970s and the 2000s. The YRP occurred mainly between the 1980s and the 1990s, and the SCP between the mid-1990s and the early 21st century. The relationship between the East Asian summer monsoon index (EASM I WF) and the four rainfall patterns was comparatively analyzed. The results confirmed that the four rainfall patterns have obvious differences in the EASM. In the NCP, IRP, or SCP years, the EASM I WF primarily showed a positive phase and a strong summer monsoon; in the YRP years, the EASM I WF primarily showed a negative phase and a weak summer monsoon.

  13. Damming of a mighty river weakens CO2 uptake capacity of the East China Sea

    NASA Astrophysics Data System (ADS)

    Tseng, C.; Gong, G.; Liu, K. K.; Shen, P.; Cai, W.

    2011-12-01

    Human activities have greatly altered the export of terrestrial materials. However, a clear link between river discharge and coastal ocean carbon cycle has not been established, nor do we know how human engineering of water resources impacts ocean CO2 uptake. Here we report strong correlations between Changjiang river discharge, river plume area in summer, and CO2 uptake in the East China Sea (ECS), which enables the assessment that a 17% reduction in CO2 uptake has resulted from the 10% reduction in discharge since the beginning of water impoundment in the Three-Gorges Dam. This constitutes strong evidence that human activity has changed the carbon cycle in one of the largest marginal seas in the world. The CO2 uptake capacity of the ECS will continue to decrease as the result of a predicted shrink of the plume area during flood season due to increased reservoir evaporation and flood regulation, increased agriculture and industrial water use, and future transport of water to the semiarid northern China.

  14. Molecular typing of Vibrio parahaemolyticus isolates from the middle-east coastline of China.

    PubMed

    Chen, Wanyi; Xie, Yanping; Xu, Jingye; Wang, Qingzhong; Gu, Ming; Yang, Jielin; Zhou, Min; Wang, Dapeng; Shi, Chunlei; Shi, Xianming

    2012-02-15

    The occurrence of outbreaks of Vibrio parahaemolyticus gastroenteritis in China highlights the need for strain characterization and subtyping of this pathogenic species. A total of 56 epidemiologically-unrelated strains of V. parahaemolyticus were isolated from clinical samples, seafood and various environmental sites in the middle-east coastline of China from 2006 to 2008. The isolates were characterized using four molecular typing methods, including ribotyping, enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR), pulsed-field gel electrophoresis (PFGE), and sequence analysis of the gyrB gene. Genetic profiles of cluster analysis from these molecular typing tests clearly showed that there were differences in potential pathogenicity among isolates from seafood and its environments. Genetic characterization of two isolates (F13 and QS2) that originated from seafood demonstrated that they were potentially pathogenic. Discriminatory indices of four typing methods for the 56 V. parahaemolyticus isolates were differentiated by Simpson's Index of Diversity. The discriminatory index of ERIC-PCR typing was maximal (D=0.942), while that of sequence analysis of the gyrB gene was minimal (D=0.702). The discriminatory ability was greatly enhanced (D=0.966) when ERIC-PCR was coupled with sequence analysis of the gyrB gene. These results suggest that ERIC-PCR combined with sequence analysis of gyrB gene may be a reliable, rapid typing strategy for V. parahaemolyticus strains.

  15. Learning cities in East Asia: Japan, the Republic of Korea and China

    NASA Astrophysics Data System (ADS)

    Han, SoongHee; Makino, Atsushi

    2013-09-01

    Lifelong learning cities emerged in Japan in the 1980s and 1990s; in the Republic of Korea in the 2000s and 2010s; and in China mostly from 2000 onwards. They were a countermeasure to the increasing challenges of global as well as post-industrial uncertainties at the turn of the century, when cities were trying to find governmental instruments to engage in cultural processes, community building and personal development as the new way of urban life. Learning was perceived to be a panacea to solve the social problems occurring in overwhelming processes of modernisation and industrialisation. The authors of this paper assert that the practice of and research on learning cities, especially in the East Asian region, need to go beyond the technical rationalities which are guiding government tools, and explain the realities to which they are meant to be applied. In order to do this, the authors investigated three separate but inter-connected scenes found in Japan, the Republic of Korea and China, revealing that the learning city is a phenomenon which reflects complex social dynamics and the interaction of many minds. While the cases in this region are distinctive, they do share some common characteristics. The authors place these within what they term a "community relations model", which they contrast with the "individual competence model" which is usually found in initiatives of the Organisation for Economic Co-operation and Development (OECD) and schemes implemented in the area of the European Union (EU).

  16. DDTs and HCHs in sediment cores from the coastal East China Sea.

    PubMed

    Lin, Tian; Nizzetto, Luca; Guo, Zhigang; Li, Yuanyuan; Li, Jun; Zhang, Gan

    2016-01-01

    Four sediment cores were collected along the Yangtze-derived sediment transport pathway in the inner shelf of the East China Sea (ECS) for OCP analysis. The sediment records of HCHs and DDTs in estuarine environment reflected remobilization of chemicals from enhanced soil erosion associated to extreme flood events or large scale land use transformation. The sediment records in the open sea, instead, reflected long-term historical trends of OCP application in the source region. Unlike the so-called mud wedge distribution of sediment, inventories of HCHs and DDTs slightly increased from the mouth of Yangtze River alongshore toward south, suggesting the sediment deposition rate was one of factors on the exposure of chemicals within the inner shelf of the ECS. Re-suspension and transport of the Yangtze-derived sediment and consequent fractionation in grain size and TOC were also responsible for the spatial variation of inventories of catchment derived OCPs in a major repository area of the Yangtze suspended sediment. The total burdens of HCHs and DDTs in the inner shelf of the ECS were 35tons and 110tons, respectively. After 1983 (year of the official ban in China), those values were 13tons and 50tons, respectively. It appears that the Yangtze still delivers relatively high inputs of DDTs more than 30years after the official ban. High proportions of DDD+DDE and β-HCH suggested those OCPs mainly originated from historical usage in the catchment recent years.

  17. Precipitation chemistry and corresponding transport patterns of influencing air masses at Huangshan Mountain in East China

    NASA Astrophysics Data System (ADS)

    Shi, ChunE; Deng, Xueliang; Yang, Yuanjian; Huang, Xiangrong; Wu, Biwen

    2014-09-01

    One hundred and ten samples of rainwater were collected for chemical analysis at the summit of Huangshan Mountain, a high-altitude site in East China, from July 2010 to June 2011. The volume-weighted-mean (VWM) pH for the whole sampling period was 5.03. SO{4/2-} and Ca2+ were the most abundant anion and cation, respectively. The ionic concentrations varied monthly with the highest concentrations in winter/spring and the lowest in summer. Evident inter-correlations were found among most ions, indicating the common sources for some species and fully mixing characteristics of the alpine precipitation chemistry. The VWM ratio of [SO{4/2-}]/[NO{3/-}] was 2.54, suggesting the acidity of rainwater comes from both nitric and sulfuric acids. Compared with contemporary observations at other alpine continental sites in China, the precipitation at Huangshan Mountain was the least polluted, with the lowest ionic concentrations. Trajectories to Huangshan Mountain on rainy days could be classified into six groups. The rainwater with influencing air masses originating in Mongolia was the most polluted with limited effect. The emissions of Jiangxi, Anhui, Zhejiang and Jiangsu provinces had a strong influence on the overall rain chemistry at Huangshan Mountain. The rainwater with influencing air masses from Inner Mongolia was heavily polluted by anthropogenic pollutants.

  18. Observed variability of summer precipitation pattern and extreme events in East China associated with variations of the East Asian summer monsoon: VARIABILITY OF SUMMER PRECIPITATION AND EXTREME EVENT IN EAST CHINA

    SciTech Connect

    Wang, Lei; Qian, Yun; Zhang, Yaocun; Zhao, Chun; Leung, L. Ruby; Huang, Anning; Xiao, Chuliang

    2015-11-09

    This paper presents a comprehensive analysis of interannual and interdecadal variations of summer precipitation and precipitation-related extreme events in China associated with variations of the East Asian summer monsoon (EASM) from 1979-2012. A high-quality daily precipitation dataset covering 2287 weather stations in China is analyzed. Based on the precipitation pattern analysis using empirical orthogonal functions, three sub-periods of 1979-1992 (period I), 1993-1999 (period II) and 2000-2012 (period III) are identified to be representative of the precipitation variability. Similar significant variability of the extreme precipitation indices is found across four sub-regions in eastern China. The spatial patterns of summer mean precipitation, the number of days with daily rainfall exceeding 95th percentile precipitation (R95p) and the maximum number of consecutive wet days (CWD) anomalies are consistent, but opposite to that of maximum consecutive dry days (CDD) anomalies during the three sub-periods. However, the spatial patterns of hydroclimatic intensity (HY-INT) are notably different from that of the other three extreme indices, but highly correlated to the dry events. The changes of precipitation anomaly patterns are accompanied by the change of the EASM regime and the abrupt shift of the position of the west Pacific subtropical high around 1992/1993 and 1999/2000, respectively, which influence the moisture transport that contributes most to the precipitation anomalies. Lastly, the EASM intensity is linked to sea surface temperature anomaly over the tropical Indian and Pacific Ocean that influences deep convection over the oceans.

  19. Ecogenomic responses of benthic communities under multiple stressors along the marine and adjacent riverine areas of northern Bohai Sea, China.

    PubMed

    Xie, Yuwei; Hong, Seongjin; Kim, Seonjin; Zhang, Xiaowei; Yang, Jianghua; Giesy, John P; Wang, Tieyu; Lu, Yonglong; Yu, Hongxia; Khim, Jong Seong

    2017-04-01

    Benthic communities in the aquatic ecosystem are influenced by both natural and anthropogenic stressors. To understand the ecogenomic responses of sediment communities to the multiple stressors of polluted environments, the bacteria, protistan and metazoan communities in sediments from marine and adjacent riverine areas of North Bohai Sea were characterized by environmental DNA meta-systematics, and their associations with environmental variables were assessed by multiple statistical approaches. The bacterial communities were dominated by Firmicutes (mean 22.4%), Proteobacteria (mean 21.6%) and Actinobacteria (mean 21.5%). The protistan communities were dominated by Ochrophyta (33.7%), Cercozoa (18.9%) and Ciliophora (17.9%). Arthropoda (71.1%) dominated the metazoan communities in sediments. The structures of communities in sediments were shaped by both natural variables (spatial variability and/or salinity (presented as Na and Ca)) and anthropogenic contaminants, including DDTs, PAHs or metals (Cu, Al, Co, Cr, Cu, Fe, K, Mg, Mn, Ni and Zn). Particularly, the correlation network of multiple communities was modulated by the concentrations of Na and DDTs at the family level. Overall, environmental DNA meta-systematics can provide a powerful tool for biomonitoring, sediment quality assessment, and key stressors identification.

  20. Temporal and spatial distribution of red tide outbreaks in the Yangtze River Estuary and adjacent waters, China.

    PubMed

    Liu, Lusan; Zhou, Juan; Zheng, Binghui; Cai, Wenqian; Lin, Kuixuan; Tang, Jingliang

    2013-07-15

    Between 1972 and 2009, evidence of red tide outbreaks in the Yangtze River Estuary and adjacent waters was collected. A geographic information system (GIS) was used to analyze the temporal and spatial distribution of these red tides, and it was subsequently used to map the distribution of these events. The results show that the following findings. (1) There were three red tide-prone areas: outside the Yangtze River Estuary and the eastern coast of Sheshan, the Huaniaoshan-Shengshan-Gouqi waters, and the Zhoushan areas and eastern coast of Zhujiajian. In these areas, red tides occurred 174 total times, 25 of which were larger than 1000 km(2) in areal extent. After 2000, the frequency of red tide outbreaks increased significantly. (2) During the months of May and June, the red tide occurrence in these areas was 51% and 20%, respectively. (3) Outbreaks of the dominant red tide plankton species Prorocentrum dong-haiense, Skeletonema costatum, Prorocentrum dantatum, and Noctiluca scientillan occurred 38, 35, 15, and 10 times, respectively, during the study interval.

  1. Fish community diversity in the middle continental shelf of the East China Sea

    NASA Astrophysics Data System (ADS)

    Shan, Xiujuan; Jin, Xianshi; Zhou, Zhipeng; Dai, Fangqun

    2011-11-01

    The status of fishery stocks in the coastal waters of China is far from ideal, mainly due to climate change and the impacts of human activities (e.g., pollution and overfishing). Thus, the restoration and protection of fishery resources have become critical and complex. The stability and balanced structure of the fish community is a basic foundation for the protection of fishery resources. Based on data collected from bottom trawls by the R/V Beidou in continental shelf of the East China Sea in November 2006 and February 2007, changes in the composition and diversity of fish species and functional groups were analyzed. The research area was divided into offshore waters and inshore waters by the two-way indicator species analysis (TWIA). The results showed that the dominant species were different between offshore waters and inshore waters and also varied with the survey time. The most abundant family was Sciaenidae and Teraponidae in November 2006, Sciaenidae, Engraulidae and Triglidae were most abundant in February 2007. The species belonged mainly to mobile piscivores (G6), benthivores/piscivores (G4), benthivores (G3) and planktivores (G1), and the dominant species in November 2006 were commercial species (e.g. Larimichthys polyactis and Trichiurus japonicus), but small-sized species were dominant in February 2007 (e.g., Harpadon nehereus, Benthosema pterotum, Champsodon capensis, and Acropoma japonicum). The species diversity showed a similar trend as the functional group diversity. Stations with higher diversity were mainly distributed in inshore waters in February 2007, whereas higher diversity was found in offshore waters in November 2006. The highest biomass and species number were found in G6 group, followed by the G4, G5 and G1 groups. The distribution of the number of individuals of each functional group showed the opposite trend as that of the biomass distribution. In addition, the size spectra were mainly concentrated around 3-29 cm, and the individual

  2. Rapid East Asian Monsoon change during the Last Interglacial in the Bohai Sea Coastal Zone, China

    NASA Astrophysics Data System (ADS)

    Du, S.; Li, B.; Chen, M.; Zhang, D.; Xiang, R.; Niu, D.

    2013-12-01

    The Bohai Sea coastal zone of China faces the Pacific Ocean to the east and the Eurasian continent to the west, hence, this region is influenced by both the ocean and continental landmasses. The Bohai Sea coastal zone has significant monsoon climate characteristics and a strong sensitivity to climate change. The Miaodao stratigraphical section (MDS) contains historical information about climate features in the region, especially the high-frequency variations during the last interglacial, sea level changes, and the evolution of the East Asian monsoon. By analyzing the ages of different sedimentary facies in combination with proxy paleoclimatic indices (i.e., grain <63 μm fraction, average grain size (Mz), clay + silt/sand content (SC/D), magnetic susceptibility, and the ratios of Na2O/Al2O3 and (Al2O3+TOFe)/SiO2, in the fifth segments of the MDS from the last-interglacial (MDS5), we conclude that subsections 5a, 5c, and 5e were controlled by summer monsoons, whereas subsections 5b and 5d were formed when winter monsoons prevailed. These results were similar to oxygen isotope analyses from previous studies including the Spectral Mapping Project (SPECMAP) and the North Greenland Ice Core Project (NorthGRIP). Five and a half comparable oscillations in proxy indices that were dated to ca. 116.1, 118.3, 121.2, 122.7, 125.9, and 128.7 ka occurred within the MDS 5e subsection when winter monsoon winds strengthened. This millennial-scale climate variability during the Eemian period may have reached up to ten and a half oscillations with a quasi-periodicity of approximately a 1,470 year cycle during the late glacial period. This rapid period of climate change has been recorded in northern and central Europe, central Asia, as well as in East Asia. The climate forming mechanism was probably initiated by changes in solar activity, and driven by the East Asian monsoon and sea level oscillations. Comparison of Miaodao section records with other paleoclimatic records during the

  3. Burial history and thermal maturity, Rocky Mountain front ranges, foothills, and foreland, east-central British Columbia and adjacent Alberta, Canada

    SciTech Connect

    Kalkreuth, W.; McMechan, M.

    1988-11-01

    The regional pattern of maturation of Cretaceous strata in the study area was determined from vitrinite-reflectance measurements. Maturation increases from west to east across the Foothills to a maximum near the eastern limit of Foothills deformation and decreases farther east. Maturation along the eastern limit of deformation also decreases northward significantly. Reflectance measurements from Carboniferous strata exposed in the Front Ranges are much lower than values from the Lower Cretaceous near the eastern limit of deformation. Modeling using burial history curves indicates the regional maturation pattern largely reflects variations in the depth and/or duration of burial beneath Maastrichtian-Eocene foredeep deposits. However, differential vertical movements associated with the Peace River arch/embayment in the Carboniferous, Triassic, Early Cretaceous and Maastrichtian-Eocene had an important effect on the maturation pattern. Determined and estimated maturation levels for reservoir strata are consistent with the known occurrences of gas fields and oil pools, except along the relatively unexplored western margin of the study area. There, moderate maturation levels indicate a potential for wet-gas or oil preservation in shallow structures containing Triassic and Lower Carboniferous carbonates in the south. In the north, structures in the western Foothills deforming Triassic strata with lower levels of maturation are breached. 15 figures.

  4. Performance of soil particle-size distribution models for describing deposited soils adjacent to constructed dams in the China Loess Plateau

    NASA Astrophysics Data System (ADS)

    Zhao, Pei; Shao, Ming-an; Horton, Robert

    2011-02-01

    Soil particle-size distributions (PSD) have been used to estimate soil hydraulic properties. Various parametric PSD models have been proposed to describe the soil PSD from sparse experimental data. It is important to determine which PSD model best represents specific soils. Fourteen PSD models were examined in order to determine the best model for representing the deposited soils adjacent to dams in the China Loess Plateau; these were: Skaggs (S-1, S-2, and S-3), fractal (FR), Jaky (J), Lima and Silva (LS), Morgan (M), Gompertz (G), logarithm (L), exponential (E), log-exponential (LE), Weibull (W), van Genuchten type (VG) as well as Fredlund (F) models. Four-hundred and eighty samples were obtained from soils deposited in the Liudaogou catchment. The coefficient of determination (R 2), the Akaike's information criterion (AIC), and the modified AIC (mAIC) were used. Based upon R 2 and AIC, the three- and four-parameter models were both good at describing the PSDs of deposited soils, and the LE, FR, and E models were the poorest. However, the mAIC in conjunction with R 2 and AIC results indicated that the W model was optimum for describing PSD of the deposited soils for emphasizing the effect of parameter number. This analysis was also helpful for finding out which model is the best one. Our results are applicable to the China Loess Plateau.

  5. Multi-Scale Interactions Associated with the Monsoon Onset Over South China Sea and Adjacent Regions during SCSMEX-98

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.; Li, X.; Wu, H.-T.

    1999-01-01

    Using data collected during The South China Sea Monsoon Experiment (SCSMEX) (1998) as well as from the TRMM Microwave-Imager (TMI) and precipitation radar (PR), we have studied the multi-scale interactions (meso-synoptic-intraseasonal) associated with monsoon onset over South China Sea (SCS) and its subsequent evolution. Results show that the monsoon onset (defined by development of steady wind direction and heavy precipitation) over the northern SCS occurred around May 15 -17. Prevailing southerlies and southwesterlies developed over the central SCS after May 20. Shortly after, monsoon convection developed over the whole SCS region around May 23-27. The entire onset process appeared to be delayed by about a week to 10 days compared with climatology. During late spring of 1998, mid-latitude frontal systems were particularly active. These systems strongly impacted the northern SCS convection and may have been instrumental in triggering the onset of the SCS monsoon. The Tropical Oceans and Global Atmosphere (TOGA) and Bureau of Meteorology Research Centre (BMRC) radar showed a wide variety of convective systems over the Intensive Flux Array, from frontal bands to shear-banded structure, deep convection, pop-corn type shallow convection, slow moving "fine lines" to water spout. Analysis of SSM/I wind and moisture data suggested that the delayed convective activity over the SCS may be linked to the weakened northward propagation of monsoon rain band, hence contributing to a persistence of the rainband south of the Yangtze River and the disastrous flood that occurred over this region during mid to late June, 1998.

  6. Double SST fronts observed from MODIS data in the East China Sea off the Zhejiang-Fujian coast, China

    NASA Astrophysics Data System (ADS)

    He, Shuangyan; Huang, Daji; Zeng, Dingyong

    2016-02-01

    We report a double coastal front system off the Zhejiang (Zhe) and Fujian (Min) Provinces in the East China Sea in winter. In addition to the well-known Zhe-Min offshore coastal front along 50 m isobath, a secondary near-shore coastal thermal front along 20 m isobath is also apparent in December and January. The fronts were observed by Moderate Resolution Imaging Spectroradiometer (MODIS) at monthly mean nighttime sea surface temperature (SST) during 2000-2013 in terms of SST gradients. Our results showed temporal and spatial variations of the two fronts as follows: (1) both offshore front and near-shore front often co-exist between 26.5°N and 29.5°N in December and between 28.0°N and 29.5°N in January. However, only the offshore front is apparent in November and February. (2) The near-shore front is narrow (4-16 km), while the offshore front is three to four times wider (16-48 km). (3) In contrast to the well-known offshore front which exists throughout the winter with a strong intensity, the near-shore front has a shorter lifetime with a weak intensity, and has been overlooked by previous studies. Finally, we proposed that the bottom bathymetric gradients may play an important role in the frontogenesis of the double fronts.

  7. Contemporary kinematics of the Ordos block, North China and its adjacent rift systems constrained by dense GPS observations

    NASA Astrophysics Data System (ADS)

    Zhao, Bin; Zhang, Caihong; Wang, Dongzhen; Huang, Yong; Tan, Kai; Du, Ruilin; Liu, Jingnan

    2017-03-01

    The detailed kinematic pattern of the Ordos block, North China and its surrounding rift systems remains uncertain, mainly due to the low signal-to-noise ratio of the Global Positioning System (GPS) velocity data and the lack of GPS stations in this region. In this study, we have obtained a new and dense velocity field by processing GPS data primarily collected from the Crustal Motion Observation Network of China and from other GPS networks between 1998 and 2014. The GPS velocities within the Ordos block can be interpreted as counterclockwise rotation of the block about the Euler pole with respect to the Eurasia plate. Velocity profiles across the graben-bounding faults show relatively rapid right-lateral strike-slip motion along the Yinchuan graben, with a rate of 0.8-2.6 mm/a from north to south. In addition, a right-lateral slip rate of 1.1-1.6 mm/a is estimated along the central segment of the Shanxi rift. However, strike-slip motion is not detected along the northern and southern margins of the Ordos block. Conversely, significant extension motion is detected across the northwestern corner of the block, with a value of 1.6 mm/a, and along the northern segment of the Shanxi rift, where an extensional rate of 1.3-1.7 mm/a is measured. Both the Daihai and Datong basins are experiencing crustal extension. On the southwestern margin of the block, deformation across the compressional zone of the Liupanshan range is subtle; however, the far-field shorting rate is as high as 3.0 mm/a, implying that this region is experiencing ongoing compression. The results reveal that present-day fault slip occurs mainly along the block bounding faults, with the exception of faults along the northern and southern margins of the block. These results provide new insights into the nature of tectonic deformation around the Ordos block, and are useful for assessing the seismic activity in this region.

  8. Chain response of microbial loop to the decay of a diatom bloom in the East China Sea

    NASA Astrophysics Data System (ADS)

    Wu, Linnan; Lin, Shiquan; Huang, Lingfeng; Lu, Jiachang; Chen, Wenzhao; Guo, Weidong; Zhang, Wuchang; Xiao, Tian; Sun, Jun

    2016-02-01

    Algal bloom has been regarded as one of the key causes for the summer hypoxia phenomena in the bottom water adjacent to the Yangtze River estuary in the East China Sea. Although a series of biological processes within microbial loop are involved in the development of oxygen depletion during the bloom decay, little has been known about the dynamics of microorganisms in response to the decaying process of the bloom through trophic interaction context. Here, we report some preliminary results of our observations about the response of microbial loop to the bloom decay, based on the onboard incubation experiments for 10 days during a diatom bloom near the Yangtze River estuary in August, 2011. Light and dark incubations were conducted to simulate the bloom decay inside and below the euphotic layer, respectively. In the first stage of bloom decay (Day 0 to Day 4), rapid response was found in heterotrophic bacteria (HB) and ciliate growth, which was in accordance with the decrease of total Chl a, indicating a "bottom-up" control at the early stage of bloom decay. However, the increase of heterotrophic nanoflagellates (HNF) abundance was rather inconspicuous, suggesting predation pressure on HNF from ciliate or other predator at this stage. In the second stage (Day 4 to Day 8), HB and ciliate decreased rapidly with the increase of HNF, revealing the release of HNF form ciliate predation, which suggested a "top-down" control. In the last stage of our experiment (Day 8 to Day 10), the trophic interactions were more complex, but it also implied a "top-down" control within the microbial loop. Meanwhile, virus had been monitored in the whole process of our incubations. It was found that virus lysed microalgae at the first stage, and lysed HB at the second stage. In addition, the bacterial mortality was principally caused by HNF grazing in the light-sufficient incubations and by viral lysis in the light-insufficient incubations. Our results suggest tight trophic interactions

  9. Influence of Typhoon Matsa on Phytoplankton Chlorophyll-a off East China

    PubMed Central

    Shao, Jinchao; Han, Guoqi; Yang, Dezhou

    2015-01-01

    Typhoons can cause strong disturbance, mixing, and upwelling in the upper layer of the oceans. Rich nutrients from the subsurface layer can be brought to the euphotic layer, which will induce the phytoplankton to breed and grow rapidly. In this paper, we investigate the impact of an intense and fast moving tropical storm, Typhoon Matsa, on phytoplankton chlorophyll-a (Chl-a) concentration off East China. By using satellite remote sensing data, we analyze the changes of Chl-a concentration, Sea Surface Temperature (SST) and wind speed in the pre- and post-typhoon periods. We also give a preliminary discussion on the different responses of the Chl-a concentration between nearshore and offshore waters. In nearshore/coastal regions where nutrients are generally rich, the Chl-a maximum occurs usually at the surface or at the layer close to the surface. And, in offshore tropical oligotrophic oceans, the subsurface maxima of Chl-a exist usually in the stratified water column. In an offshore area east of Taiwan, the Chl-a concentration rose gradually in about two weeks after the typhoon. However, in a coastal area north of Taiwan high Chl-a concentration decreased sharply before landfall, rebounded quickly to some degree after landfall, and restored gradually to the pre-typhoon level in about two weeks. The Chl-a concentration presented a negative correlation with the wind speed in the nearshore area during the typhoon, which is opposite to the response in the offshore waters. The phenomena may be attributable to onshore advection of low Chl-a water, coastal downwelling and intensified mixing, which together bring pre-typhoon surface Chl-a downward in the coastal area. In the offshore area, the typhoon may trigger increase of Chl-a concentration through uptake of nutrients by typhoon-induced upwelling and entrainment mixing. PMID:26407324

  10. Uncertainty evaluation of copula analysis of hydrological droughts in the East River basin, China

    NASA Astrophysics Data System (ADS)

    Zhang, Qiang; Xiao, Mingzhong; Singh, Vijay P.

    2015-06-01

    The joint probability behaviors of extreme hydro-meteorological events, such as droughts, have been receiving increasing attentions in recent years. Since extreme hydro-meteorological events are reflected by more than one variable, such as duration and intensity, copula functions have been widely applied. However, uncertainties of copula-based analysis of hydrological droughts as a result of selection of marginal distribution and copulas have not yet received significant concerns. The aim of this study is to evaluate such uncertainties based on Bayesian approach. The method is used to analyze hydrological drought in the East River basin (China), which is the principal supplier of water resources for megacities in the Pearl River Delta and also for Hong Kong. The results indicate that the credible intervals of most likely design drought events with a return period of 20 years in terms of drought severity and duration are considerably large at all stations in the East River basin, covering the drought event curves at return periods of 10 and 50 years. Also the influences of heavy-tailed marginal distribution on the uncertainty evaluation of joint distribution have been investigated. Results show that the stronger the heavy-tailed marginal distribution, the greater the uncertainty of the joint distribution, especially for the extreme event. Results of this study provide a technical reference for uncertainty evaluation in copula-based analysis of drought events at regional and global scales. The large credible interval of drought severity and duration greatly challenges measures of mitigation of drought hazards and water resource management.

  11. Influence of Typhoon Matsa on Phytoplankton Chlorophyll-a off East China.

    PubMed

    Zhao, Hui; Shao, Jinchao; Han, Guoqi; Yang, Dezhou; Lv, Jianhai

    2015-01-01

    Typhoons can cause strong disturbance, mixing, and upwelling in the upper layer of the oceans. Rich nutrients from the subsurface layer can be brought to the euphotic layer, which will induce the phytoplankton to breed and grow rapidly. In this paper, we investigate the impact of an intense and fast moving tropical storm, Typhoon Matsa, on phytoplankton chlorophyll-a (Chl-a) concentration off East China. By using satellite remote sensing data, we analyze the changes of Chl-a concentration, Sea Surface Temperature (SST) and wind speed in the pre- and post-typhoon periods. We also give a preliminary discussion on the different responses of the Chl-a concentration between nearshore and offshore waters. In nearshore/coastal regions where nutrients are generally rich, the Chl-a maximum occurs usually at the surface or at the layer close to the surface. And, in offshore tropical oligotrophic oceans, the subsurface maxima of Chl-a exist usually in the stratified water column. In an offshore area east of Taiwan, the Chl-a concentration rose gradually in about two weeks after the typhoon. However, in a coastal area north of Taiwan high Chl-a concentration decreased sharply before landfall, rebounded quickly to some degree after landfall, and restored gradually to the pre-typhoon level in about two weeks. The Chl-a concentration presented a negative correlation with the wind speed in the nearshore area during the typhoon, which is opposite to the response in the offshore waters. The phenomena may be attributable to onshore advection of low Chl-a water, coastal downwelling and intensified mixing, which together bring pre-typhoon surface Chl-a downward in the coastal area. In the offshore area, the typhoon may trigger increase of Chl-a concentration through uptake of nutrients by typhoon-induced upwelling and entrainment mixing.

  12. Seasonal variation of organochlorine pesticides in the gaseous phase and aerosols over the East China Sea

    NASA Astrophysics Data System (ADS)

    Ji, Tianyi; Lin, Tian; Wang, Fengwen; Li, Yuanyuan; Guo, Zhigang

    2015-05-01

    Eighty paired gaseous phase and PM2.5 (particulate matter < 2.5 μm in diameter) samples, covering four seasons from October 2011 to August 2012 were collected simultaneously from a remote island in the East China Sea (ECS). The samples were analyzed for organochlorine pesticides (OCPs) to determine their seasonal variation and potential sources over the coastal marine environment. The concentrations of individual OCPs in the PM2.5 samples were higher in winter and lower in summer, and the reverse trend was observed for the measured OCP compounds (except hexachlorocyclohexanes, HCHs) in the gaseous phase. Principal component analysis revealed one trend that contributed 40% to PM2.5-bound OCPs characterized by β-HCH, α-HCH, p,p‧-dichlorodiphenyldichloroethane (p,p‧-DDD), p,p‧-dichlorodiphenyldichloroethylene (p,p‧-DDE), and chlordanes; whereas two seasonal trends, represented by dichlorodiphenyltrichloroethanes (DDTs) or chlordanes and HCHs, were responsible for 38% and 23% of the gaseous OCPs, respectively. Continental outflow driven by the East Asian monsoon brought large quantities of particulate OCPs to the ECS, especially in winter. Possible fresh sources or net volatilization from the Yangtze River induced by both higher ambient temperature and higher discharge rates caused the higher gaseous DDT and chlordane levels observed in summer. However, the lower concentrations of gaseous HCHs observed in summer suggested that net volatilization had a relatively limited impact on gaseous HCHs due to the long-term prohibition of their use and their low residual levels in the catchment, whereas the elevated concentrations of gaseous HCHs in winter controlled by gas-particle partitioning, resulted from increased particulate HCHs producing a partial shift to gaseous HCHs over ECS.

  13. Modeling of soil erosion and sediment transport in the East River Basin in southern China

    USGS Publications Warehouse

    Wu, Yping; Chen, Ji

    2012-01-01

    Soil erosion is a major global environmental problem that has caused many issues involving land degradation, sedimentation of waterways, ecological degradation, and nonpoint source pollution. Therefore, it is significant to understand the processes of soil erosion and sediment transport along rivers, and this can help identify the erosion prone areas and find potential measures to alleviate the environmental effects. In this study, we investigated soil erosion and identified the most seriously eroded areas in the East River Basin in southern China using a physically-based model, Soil and Water Assessment Tool (SWAT). We also introduced a classical sediment transport method (Zhang) into SWAT and compared it with the built-in Bagnold method in simulating sediment transport process along the river. The derived spatial soil erosion map and land use based erosion levels can explicitly illustrate the identification and prioritization of the critical soil erosion areas in this basin. Our results also indicate that erosion is quite sensitive to soil properties and slope. Comparison of Bagnold and Zhang methods shows that the latter can give an overall better performance especially in tracking the peak and low sediment concentrations along the river. We also found that the East River is mainly characterized by sediment deposition in most of the segments and at most times of a year. Overall, the results presented in this paper can provide decision support for watershed managers about where the best management practices (conservation measures) can be implemented effectively and at low cost. The methods we used in this study can also be of interest in sediment modeling for other basins worldwide.

  14. Crustal structure beneath Liaoning province and the Bohai Sea and its adjacent region in China based on ambient noise tomography

    NASA Astrophysics Data System (ADS)

    Pang, Guang-hua; Feng, Ji-Kun; Lin, Jun

    2017-03-01

    The velocity structure of the crust beneath Liaoning province and the Bohai sea in China was imaged using ambient seismic noise recorded by 73 regional broadband stations. All available three-component time series from the 12-month span between January and December 2013 were cross-correlated to yield empirical Green's functions for Rayleigh and Love waves. Phase-velocity dispersion curves for the Rayleigh waves and the Love waves were measured by applying the frequency-time analysis method. Dispersion measurements of the Rayleigh wave and the Love wave were then utilized to construct 2D phase-velocity maps for the Rayleigh wave at 8-35 s periods and the Love wave at 9-32 s periods, respectively. Both Rayleigh and Love phase-velocity maps show significant lateral variations that are correlated well with known geological features and tectonics units in the study region. Next, phase dispersion curves of the Rayleigh wave and the Love wave extracted from each cell of the 2D Rayleigh wave and Love wave phase-velocity maps, respectively, were inverted simultaneously to determine the 3D shear wave velocity structures. The horizontal shear wave velocity images clearly and intuitively exhibit that the earthquake swarms in the Haicheng region and the Tangshan region are mainly clustered in the transition zone between the low- and high-velocity zones in the upper crust, coinciding with fault zones, and their distribution is very closely associated with these faults. The vertical shear wave velocity image reveals that the lower crust downward to the uppermost mantle is featured by distinctly high velocities, with even a high-velocity thinner layer existing at the bottom of the lower crust near Moho in central and northern the Bohai sea along the Tanlu fault, and these phenomena could be caused by the intrusion of mantle material, indicating the Tanlu fault could be just as the uprising channel of deep materials.

  15. Assessment of the Impact of The East Asian Summer Monsoon on the Air Quality Over China from space

    NASA Astrophysics Data System (ADS)

    Hao, N.; Ding, A.; Valks, P.; Safieddine, S.; Clerbaux, C.; Trautmann, T.

    2013-12-01

    Air pollution is one of the most important environmental problems in developing Asian countries like China. Due to huge consumption of fossil fuels and rapid increase of traffic emissions in the past decades, many regions in China have been experiencing heavy air pollution. In China, studies showed that the East Asian monsoon plays a significant role in characterizing the temporal variation and spatial patterns of air pollution, since monsoon is a major atmospheric system affecting air mass transport, convection, and precipitation. Publicly available in situ observations cannot provide sufficient spatial coverage and high consistence in data quality for a long-term period. Therefore, knowledge gaps still exist in the understanding of Asian monsoon impact on the air quality in China under the background of global climate change. Satellite retrievals with high spatial coverage and high consistence for a long period can well document the change of air pollution with monsoon. We apply multi-platform satellite observations by the GOME, SCIAMACHY, GOME-2, IASI, GOMOS, MIPAS and MOPITT instruments to analyze tropospheric ozone and CO, precursors of ozone (NOx, HCHO and CH4) and other related trace gases over China. The potential of using the current generation of satellite instruments to monitor air quality changes caused by the East Asian monsoon circulation will be presented. Preliminary comparison results between satellite measurement and limited but valuable ground-based and aircraft measurements will also be showed.

  16. High-resolution depositional records of polycyclic aromatic hydrocarbons in the central continental shelf mud of the East China Sea

    SciTech Connect

    Zhigang Guo; Tian Lin; Gan Zhang; Zuosheng Yang; Ming Fang

    2006-09-01

    A well-placed {sup 210}Pb-dated sediment core extracted from the distal mud in the central continental shelf of the East China Sea is used to reconstruct the high-resolution atmospheric depositional record of polycyclic aromatic hydrocarbons (PAHs), believed to be transported mainly from China in the past 200 years due to the East Asian Monsoon. Total PAHs (TPAHs), based on the 16 USEPA priority PAHs, range from 27 in 1788 to 132 ng g{sup -1} in 2001. TPAH variation in the core reflects energy usage changes and follows closely the historical economic development in China. PAHs in the core are dominantly pyrogenic in source, i.e., they are mainly from the incomplete combustion of coal and biomass burning. Several individual PAHs suggest that contribution from incomplete petroleum combustion has increased during recent years. Analysis of the 2 + 3 ring and the 5 + 6 ring PAHs and principle component analysis provide more evidence in the change in the energy structure, especially after 1978 when China embarked on the 'Reform and Open' Policy, indicating the transformation from an agricultural to an industrial economy of China. The historical profile of PAH distribution in the study area is obviously different from the United States and Europe due to their difference in energy structure and economic development stages. 39 refs., 5 figs.

  17. Numerical Simulation of Air Mass Modification Over the East China Sea during the Winter Season

    NASA Astrophysics Data System (ADS)

    Hsu, Wu-Ron

    Air mass modification over the East China Sea during cold air outbreaks in the winter season was simulated by utilizing a high-resolution numerical model. The model includes most of the major physical processes, such as, surface exchange of heat and moisture between water and air; condensation and evaporation; and vertical turbulent transfer of heat, moisture, and momentum. The simulated convective boundary layer (CBL) consists of a surface layer, a subcloud layer, and a cloud layer. It is capped by an inversion with strong temperature and moisture gradients. Mesoscale cellular convection (MCC) embedded within the convective layer moves along with the mean wind. The average aspect ratio of the cells is 17.5, which agrees with observed aspect ratios for convective cells over the East China Sea. The upward convective motion correlates very well with the appearance of clouds, higher temperature, and higher moisture content in the CBL. The effects of diabatic heating were found to be very important in driving the thermal convection. Without the release of latent heat, the convective layer would be very shallow, and the convective motion would be greatly suppressed. Even though the formulation and dissipation of a cloud is associated with the movement of the resolvable scale MCC, the vertical transport of heat and moisture is achieved mainly by the unresolvable turbulent eddies. The distribution of specific humidity during the passage of the surface front reveals the moisture being pushed upward along the frontal surface as observed. The cold and dry air behind the cold front is quickly modified by strong convection over the warm water surface, especially over the Kuroshio Current. A cloud-free region exists near the coast where the CBL is too shallow for clouds to develop. A layer of stratocumulus forms downstream from the cloud-free region. The depth of the CBL increases toward the Kuroshio Current due to strong heat and moisture fluxes from the water surface. The CBL

  18. The correspondence analysis of the satellite gravity anomalies with the deep lithosphere structure of the East China Sea

    NASA Astrophysics Data System (ADS)

    Yao, C.; Meng, X.; Guo, W.; Zheng, Y.; Gao, D.; Li, H.; He, H.

    2010-12-01

    Based on the satellite gravity data, and the trial analysis of various parameters, the terrain correction and the correction of sea water are carried out to obtain the Bouguer gravity anomalies of the continental shelf of the East China Sea to the Phillipine Basin. The inversion of gravity anomalies and modeling are developed with the constraints of the results of seismic profiles. To infer the deep lithospheric structure of the East China Sea, the shallow geological structure is firstly analyzed. Finally, a gravity model of explanation is provided to demonstrate the site of subduction of the Phillipine plate toward the Eurasia plat, and to show the variation of the Moho and the changes of thickness of lithosphere.

  19. A fine grid two-dimensional M{sub 2} tidal model of the East China Sea

    SciTech Connect

    Han, K.M.; Choi, B.H.

    1993-12-31

    The previous two-dimensional non-linear tidal model of the East China Sea (Chung, 1986) has been further refined to resolve the flow over the continental shelf in more detail. The mesh resolution of the present finite-difference grid system used is 4 minutes latitude by 5 minutes longitude over the entire shelf. The developed fine grid two-dimensional model was utilized to reproduce the M{sub 2} tide and M{sub 4} tide for the East China Sea continental shelf. There is general agreement between the model results and the current observation made in the Eastern Yellow Sea, which supports the calculated tidal regime over the shelf. Some preliminary results on maximum bottom stress and tidally-induced residual current were also examined and discussed.

  20. Phthalic acid esters in soils from vegetable greenhouses in Shandong Peninsula, East China.

    PubMed

    Chai, Chao; Cheng, Hongzhen; Ge, Wei; Ma, Dong; Shi, Yanxi

    2014-01-01

    Soils at depths of 0 cm to 10 cm, 10 cm to 20 cm, and 20 cm to 40 cm from 37 vegetable greenhouses in Shandong Peninsula, East China, were collected, and 16 phthalic acid esters (PAEs) were detected using gas chromatography-mass spectrometry (GC-MS). All 16 PAEs could be detected in soils from vegetable greenhouses. The total of 16 PAEs (Σ16PAEs) ranged from 1.939 mg/kg to 35.442 mg/kg, with an average of 6.748 mg/kg. Among four areas, including Qingdao, Weihai, Weifang, and Yantai, the average and maximum concentrations of Σ16PAEs in soils at depths of 0 cm to 10 cm appeared in Weifang, which has a long history of vegetable production and is famous for extensive greenhouse cultivation. Despite the different concentrations of Σ16PAEs, the PAE compositions were comparable. Among the 16 PAEs, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DnOP), di-n-butyl phthalate (DnBP), and diisobutyl phthalate (DiBP) were the most abundant. Compared with the results on agricultural soils in China, soils that are being used or were used for vegetable greenhouses had higher PAE concentrations. Among PAEs, dimethyl phthalate (DMP), diethyl phthalate (DEP) and DnBP exceeded soil allowable concentrations (in US) in more than 90% of the samples, and DnOP in more than 20%. Shandong Peninsula has the highest PAE contents, which suggests that this area is severely contaminated by PAEs.

  1. Climatic Warming Increases Winter Wheat Yield but Reduces Grain Nitrogen Concentration in East China

    PubMed Central

    Deng, Aixing; Song, Zhenwei; Zhang, Baoming; Zhang, Weijian

    2014-01-01

    Climatic warming is often predicted to reduce wheat yield and grain quality in China. However, direct evidence is still lacking. We conducted a three-year experiment with a Free Air Temperature Increase (FATI) facility to examine the responses of winter wheat growth and plant N accumulation to a moderate temperature increase of 1.5°C predicted to prevail by 2050 in East China. Three warming treatments (AW: all-day warming; DW: daytime warming; NW: nighttime warming) were applied for an entire growth period. Consistent warming effects on wheat plant were recorded across the experimental years. An increase of ca. 1.5°C in daily, daytime and nighttime mean temperatures shortened the length of pre-anthesis period averagely by 12.7, 8.3 and 10.7 d (P<0.05), respectively, but had no significant impact on the length of the post-anthesis period. Warming did not significantly alter the aboveground biomass production, but the grain yield was 16.3, 18.1 and 19.6% (P<0.05) higher in the AW, DW and NW plots than the non-warmed plot, respectively. Warming also significantly increased plant N uptake and total biomass N accumulation. However, warming significantly reduced grain N concentrations while increased N concentrations in the leaves and stems. Together, our results demonstrate differential impacts of warming on the depositions of grain starch and protein, highlighting the needs to further understand the mechanisms that underlie warming impacts on plant C and N metabolism in wheat. PMID:24736557

  2. Climatic warming increases winter wheat yield but reduces grain nitrogen concentration in east China.

    PubMed

    Tian, Yunlu; Zheng, Chengyan; Chen, Jin; Chen, Changqing; Deng, Aixing; Song, Zhenwei; Zhang, Baoming; Zhang, Weijian

    2014-01-01

    Climatic warming is often predicted to reduce wheat yield and grain quality in China. However, direct evidence is still lacking. We conducted a three-year experiment with a Free Air Temperature Increase (FATI) facility to examine the responses of winter wheat growth and plant N accumulation to a moderate temperature increase of 1.5°C predicted to prevail by 2050 in East China. Three warming treatments (AW: all-day warming; DW: daytime warming; NW: nighttime warming) were applied for an entire growth period. Consistent warming effects on wheat plant were recorded across the experimental years. An increase of ca. 1.5°C in daily, daytime and nighttime mean temperatures shortened the length of pre-anthesis period averagely by 12.7, 8.3 and 10.7 d (P<0.05), respectively, but had no significant impact on the length of the post-anthesis period. Warming did not significantly alter the aboveground biomass production, but the grain yield was 16.3, 18.1 and 19.6% (P<0.05) higher in the AW, DW and NW plots than the non-warmed plot, respectively. Warming also significantly increased plant N uptake and total biomass N accumulation. However, warming significantly reduced grain N concentrations while increased N concentrations in the leaves and stems. Together, our results demonstrate differential impacts of warming on the depositions of grain starch and protein, highlighting the needs to further understand the mechanisms that underlie warming impacts on plant C and N metabolism in wheat.

  3. Variations of atmospheric CH4, N2O and SF6 over Japan and the East China Sea

    NASA Astrophysics Data System (ADS)

    Ishijima, K.; Goto, D.; Ishidoya, S.; Yashiro, H.; Umezawa, T.; Sugawara, S.; Patra, P. K.; Muromachi, A.; Elkins, J. W.; Dutton, G. S.; Dlugokencky, E. J.; Morimoto, S.; Aoki, S.; Nakazawa, T.

    2013-12-01

    East Asia is one of the most important regions for anthropogenic sources of both short-lived air pollutants and long-lived greenhouse gases (GHGs). According to recent estimates from an emission database, China has become the largest emitter of long-lived GHGs. Since Japan and the East China Sea are located at the east end of Eurasia, atmospheric species emitted from the continent are transported over them throughout the year. Particularly in winter to spring, outflow of the emitted species is enhanced over the East China Sea due to the East Asian Monsoon. To monitor temporal and spatial variability of atmospheric GHGs in the East Asian region, we conducted systematic GHG observations during 2003-2012 from flask samples collected onboard four different commercial ferry boats, which connected between Wakkanai and Rishiri islands (WAK ; 45.4°N, 141.5°E), between Sakaiminato and Oki islands (OKI ; 35.8°N, 133.2°E), between Kagoshima and Okinawa islands (RYU ; 30.0°N, 130.0°E), and between Ishigaki and Hateruma islands (HTR ; 24.0°N, 124.0°E). Air samples were collected almost weekly, and they were sent to Tohoku University and analyzed for GHGs and related gases. In this study, we present analyses of observed CH4, N2O and SF6 concentrations in comparison with simulations by the Atmospheric general circulation model-based Chemistry Transport model (ACTM). The observed three species predictably show higher concentrations than those observed at Cape Kumukahi (KUM), which is a NOAA air sampling site located in the Central Pacific, reflecting strong outflow of the species from East Asia. Annual mean latitudinal gradients found from the four locations as well as decrease toward KUM are generally reproduced by the ACTM. This is mostly because of reasonable spatial distributions in GHG emissions given in the ACTM. The three species also show discernible seasonal cycles. ACTM simulates seasonal cycles of CH4 and SF6 relatively well, but not for N2O, suggesting

  4. Impacts of the East Asian Monsoon on springtime dust concentrations over China: IMPACTS OF MONSOON ON DUST

    SciTech Connect

    Lou, Sijia; Russell, Lynn M.; Yang, Yang; Xu, Li; Lamjiri, Maryam A.; DeFlorio, Michael J.; Miller, Arthur J.; Ghan, Steven J.; Liu, Ying; Singh, Balwinder

    2016-07-12

    We use 150 year preindustrial simulations of the Community Earth System Model to quantify the impacts of the East Asian Monsoon strength on interannual variations of springtime dust concentrations over China. The simulated interannual variations in March-April-May (MAM) dust column concentrations range between 20–40% and 10–60% over eastern and western China, respectively. The dust concentrations over eastern China correlate negatively with the East Asian Monsoon (EAM) index, which represents the strength of monsoon, with a regionally averaged correlation coefficient of 0.64. Relative to the strongest EAM years, MAMdust concentrations in the weakest EAM years are higher over China, with regional relative differences of 55.6%, 29.6%, and 13.9% in the run with emissions calculated interactively and of 33.8%, 10.3%, and 8.2% over eastern, central, and western China, respectively, in the run with prescribed emissions. Both interactive run and prescribed emission run show the similar pattern of climate change between the weakest and strongest EAM years. Strong anomalous northwesterly and westerly winds over the Gobi and Taklamakan deserts during the weakest EAM years result in larger transport fluxes, and thereby increase the dust concentrations over China. These differences in dust concentrations between the weakest and strongest EAM years (weakest-strongest) lead to the change in the net radiative forcing by up to 8 and 3Wm2 at the surface, compared to 2.4 and +1.2Wm2 at the top of the atmosphere over eastern and western China, respectively.

  5. Effects of the Changjiang (Yangtze) River discharge on planktonic community respiration in the East China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Chung-Chi; Shiah, Fuh-Kwo; Chiang, Kuo-Ping; Gong, Gwo-Ching; Kemp, W. Michael

    2009-03-01

    Planktonic communities tend to flourish on the western margins of the East China Sea (ECS) fueled by substrates delivered largely from the Changjiang River, the fifth largest river in the world. To study the effects of the Changjiang River discharge on planktonic community respiration (CR), physical-chemical variables and key processes were measured in three consecutive summers in the ECS. Results showed that concentrations of nitrate and Chl a, protozoan biomass, bacterial production, as well as CR in the surface water were all negatively correlated with sea surface salinity, reflecting the strong influence of river discharge on the ECS shelf ecosystem. Moreover, mean values of nitrate, Chl a concentrations, and CR rates were proportionally related to the area of Changjiang diluted water (CDW; salinity ≤31.0 practical salinity units (psu)), an index of river discharge rate. Presumably, higher river flow delivers higher nutrient concentrations which stimulate phytoplankton growth, which in turn fuels CR. CR exhibited significant monthly and interannual variability, and rates appear to be dominated by bacteria and phytoplankton. Although the plankton community was relatively productive (mean = 0.8 mg C m-2 d-1) in the CDW, the mean ratio of production to respiration was low (0.42). This suggests that the heterotrophic processes regulating CR were supported by riverine organic carbon input in addition to in situ autotrophic production.

  6. A Case study of the daytime D-layer height variation in East China

    NASA Astrophysics Data System (ADS)

    Qin, Z.; Zhu, B.; Lu, F.; Ma, D.

    2013-12-01

    During the summer of 2012, six spaced stations were deployed in Jianghuai Area in East China. Each station was equipped with the newly improved VLF/LF lightning continuous recording system, which could give a more real and effective description of the lightning VLF/LF radiation during the thunderstorms. On July 7th, millions of lightning VLF/LF signals were collected during the daytime (8:00-18:00, local time). The time domain signal of negative return strokes (-RS) which occurred between 400 km and 600 km away from the central station, were analyzed to retrieve the effective ionosphere D-layer height, by comparing the time difference between direct ground wave and first-hop ionospheric reflection of lightning return strokes. During 8:00-18:00 (LT), D-layer height fluctuates between 55-70 km, with a lower height at noon and a higher height at morning and early evening. The overall variation of ionosphere heights is highly correlated with the variation of X-ray flux recorded by GOES satellite.

  7. Using rare earth elements to constrain particulate organic carbon flux in the East China Sea.

    PubMed

    Hung, Chin-Chang; Chen, Ya-Feng; Hsu, Shih-Chieh; Wang, Kui; Chen, Jian Feng; Burdige, David J

    2016-09-27

    Fluxes of particulate organic carbon (POC) in the East China Sea (ECS) have been reported to decrease from the inner continental shelf towards the outer continental shelf. Recent research has shown that POC fluxes in the ECS may be overestimated due to active sediment resuspension. To better characterize the effect of sediment resuspension on particle fluxes in the ECS, rare earth elements (REEs) and organic carbon (OC) were used in separate two-member mixing models to evaluate trap-collected POC fluxes. The ratio of resuspended particles from sediments to total trap-collected particles in the ECS ranged from 82-94% using the OC mixing model, and 30-80% using the REEs mixing model, respectively. These results suggest that REEs may be better proxies for sediment resuspension than OC in high turbidity marginal seas because REEs do not appear to undergo degradation during particle sinking as compared to organic carbon. Our results suggest that REEs can be used as tracers to provide quantitative estimates of POC fluxes in marginal seas.

  8. Study on the storm surges induced by cold waves in the Northern East China Sea

    NASA Astrophysics Data System (ADS)

    Mo, Dongxue; Hou, Yijun; Li, Jian; Liu, Yahao

    2016-08-01

    Cold wave, a kind of severe weather system, can bring strong wind and induce significant sea level rise to the Northern East China Sea. Based on CFSR data, the study shows the monthly distributions of invaded days and the spatiotemporal distributions of cold-wave wind direction and wind speed. A three-dimensional numerical model (ROMS) was developed to study storm surges induced by cold waves. The role of wind direction, wind speed, wind duration, extratropical cyclone and tide-surge interaction is investigated by conducting different sensitivity experiments. The results indicate that storm surges mainly happen at the coasts perpendicular to the wind directions. Surge range and time lag are related to the geometry of the basin and the continental shelf. The response of the sea-level fluctuations to cold wave indicates that there is a positive correlation between crests and wind speed, a negative correlation between troughs and wind speed, but no obvious correlations to wind duration. Coupled weather cold waves, which yield a larger range and a multi-peak structure of surges, can be classified according to cold wave tracks and extratropical cyclones. The tide-surge interaction has an obvious and different effect on the magnitudes and phases of storm surges for different tidal stages.

  9. Simultaneous retrieval of aerosol optical thickness and chlorophyll concentration from multiwavelength measurement over East China Sea

    NASA Astrophysics Data System (ADS)

    Shi, Chong; Nakajima, Teruyuki; Hashimoto, Makiko

    2016-12-01

    A flexible inversion algorithm is proposed for simultaneously retrieving aerosol optical thickness (AOT) and surface chlorophyll a (Chl) concentration from multiwavelength observation over the ocean. In this algorithm, forward radiation calculation is performed by an accurate coupled atmosphere-ocean model with a comprehensive bio-optical ocean module. Then, a full-physical nonlinear optimization approximation approach is used to retrieve AOT and Chl. For AOT retrieval, a global three-dimensional spectral radiation-transport aerosol model is used as the a priori constraint to increase the retrieval accuracy of aerosol. To investigate the algorithm's availability, the retrieval experiment is conducted using simulated radiance data to demonstrate that the relative errors in simultaneously determining AOT and Chl can be mostly controlled to within 10% using multiwavelength and angle covering in and out of sunglint. Furthermore, the inversion results are assessed using the actual satellite observation data obtained from Cloud and Aerosol Imager (CAI)/Greenhouse gas Observation SATellite GOSAT and MODerate resolution Imaging Spectroradiometer (MODIS)/Aqua instruments through comparison to Aerosol Robotic Network (AERONET) aerosol and ocean color (OC) products over East China Sea. Both the retrieved AOT and Chl compare favorably to the reported AERONET values, particularly when using the CASE 2 ocean module in turbid water, even when the retrieval is performed in the presence of high aerosol loading and sunglint. Finally, the CAI and MODIS images are used to jointly retrieve the spatial distribution of AOT and Chl in comparison to the MODIS AOT and OC products.

  10. Assessment of lead bioaccessibility in soils around lead battery plants in East China.

    PubMed

    Jin, Zan-fang; Zhang, Zhuo-jun; Zhang, Hui; Liu, Cong-qiang; Li, Fei-li

    2015-01-01

    Soil ingestion is an important human exposure pathway for lead (Pb). A modified physiologically based extraction test was applied to 70 soil samples from five battery plants in East China. The mean values for soil pH, soil organic matter, Fe and Mn concentrations ranged from 5.9% to 8.1, 0.37% to 2.2%, 2.78% to 3.75%, and 507-577 mg kg(-1), respectively, while Pb concentrations ranged widely in 14.3-2000 mg kg(-1). The isotopic ratios of 14 soils from one of the five battery plants formed a straight line in the plot of (208)Pb/(206)Pb vs. (207)Pb/(206)Pb, indicating Pb emissions from the lead battery plant as the dominant anthropogenic source within 200 m. Lead bioaccessibility in the soils ranged from 4.1% to 66.9% in the gastric phase and from 0.28% to 9.29% in the gastrointestinal phase. Multiple step regressions identified modes as BAgastric=-106.8+0.627[Pb]+19.1[Fe]+11.3[SOM], and BAgastrointestinal=-2.852+0.078[Pb].

  11. [Fluorescence characterization of dissolved organic matter in the East China Sea after diatom red tide dispersion].

    PubMed

    Zhuo, Peng-ji; Zhao, Wei-hong

    2009-05-01

    Fluorescence excitation-emission spectroscopy (EEMS) was employed to analyze the 3-dimensional fluorescence of dissolved organic matter in the East China Sea after diatom red tide dispersion. The relationships between fluorescence peak intensity, and salinity and chlorophyll-a were discussed. The centers of protein-like fluorescence peaks dispersed at Exmax/Exmax = 270-280/290-315 nm (Peak B), 220-230/290-305 nm (Peak D), 230-240/335-350 nm (Peak S) and 280/320 nm (Peak T). Two humic-like peaks appeared at 255-270/435-480 nm (Peak A)and 330-350/420-480 nm (Peak C). High tyrosine-like intensity was observed in diatom red tide dispersion area, and tryptophan-like fluorescence was also found which was lower. High FIB/FIS showed that diatom red tide produced much tyrosine-like matter during dispersion. Peaks S, A and C had positive correlation with one another, and their distributions were similar, which decreased with distance increasing away from the shore. Good negative correlations between peaks S, A and C and salinity suggested that Jiangsu-Zhejiang coastal water was the same source of them. Correlations between fluorescence peak intensity and chlorophyll-a were not remarkable enough to clear the relationship between fluorescence and living algal matter. It was supposed that the living algal matter contributed little to the fluorescence intensity of algal dispersion seawater.

  12. In situ detrimental impacts of Prorocentrum donghaiense blooms on zooplankton in the East China Sea.

    PubMed

    Lin, Jia-Ning; Yan, Tian; Zhang, Qing-Chun; Wang, Yun-Feng; Liu, Qing; Zhou, Ming-Jiang

    2014-11-15

    Large-scale algal blooms of the dinoflagellate Prorocentrum donghaiense have occurred frequently in the East China Sea (ECS) in recent decades. However, its impacts on the zooplankton in situ are still under not well understood. During a spring P. donghaiense bloom (April-May 2013) along the northern coast of Fujian Province (120°-121°30″E, 26°30″-28°N), we found that the bloom decreased the abundance of copepods and had no significant effect on chaetognaths and small jellyfish. However, the abundance of small jellyfish increased over the course of the study. The zooplankton community changed from being copepod and small jellyfish- to small jellyfish-dominated during the bloom. In the bloom areas, the copepod Calanus sinicus showed higher mortality and lower egg production rates (EPR) than those in the non-bloom areas. The results suggested that P. donghaiense blooms had detrimental effects on the structure of zooplankton community and the recruitments of C. sinicus.

  13. The impact of atmospheric deposition of cadmium on dominant algal species in the East China Sea

    NASA Astrophysics Data System (ADS)

    Quan, Qiwei; Chen, Ying; Ma, Qingwei; Wang, Fujiang; Meng, Xi; Wang, Bo

    2016-04-01

    Cadmium (Cd) mainly derived from anthropogenic emissions can be transported through atmospheric pathway to marine ecosystem, affecting the phytoplankton community and primary productivity. In this study, we identified the toxicity threshold of Cd for phytoplankton under seawater conditions of the coastal East China Sea (ECS) through both laboratory and in situ mesocosm incubation experiments. The mesocosm experiment showed that Cd in low concentration (0.003 μg per μg chl a) was conducive to the growth of natural community and increased chl a productivity. In high concentration (0.03 μg per μg chl a) Cd acted as an inhibiting factor which decreased the total chl a productivity. The diatom community was found to be more sensitive to Cd toxicity than dinoflagellate, as the low concentration Cd showed toxicity to diatom but enhanced dinoflagellate growth. We noticed that the soluble Cd estimated from atmosphere deposition to the coastal ECS was below the toxicity threshold and the Cd deposition might promote phytoplankton growth in this region. In our laboratory experiments, adding Cd, similar to aerosol deposition, stimulated the growth of both dominant algal species Prorocentrum donghaiense Lu (dinoflagellate) and Skeletonema costatum (diatom). Adding Cd on a higher level inhibited the growth of both the species, but Skeletonema costatum seemed obviously more sensitive to toxicity. This indicates the potential impact of atmospheric deposition Cd on phytoplankton community succession in the ECS.

  14. Paragnomoxyala gen. nov. (Xyalidae, Monhysterida, Nematoda) from the East China Sea.

    PubMed

    Jiang, Weijun; Huang, Yong

    2015-11-05

    A new genus, Paragnomoxyala gen. nov., and a new species, Paragnomoxyala breviseta sp. nov. are described from the East China Sea. Paragnomoxyala gen. nov. is characterized by having large funnel-shaped buccal cavity with cuticularized walls and extended anteriorly; lips very high; striated cuticle; four cephalic setae, absence of outer labial setae; circular amphidial fovea; straight spicules and absence of gubernaculum; tail conico-cylindrical with three terminal setae; female monodelphic with an anterior outstretched ovary. It differs from similar genera by having a large buccal cavity unique in Xyalidae, straight spicules, lacking gubernaculum, and conico-cylindrical tail with terminal setae. Paragnomoxyala breviseta sp. nov. is characterized by having a large funnel-shaped buccal cavity, with cuticularized walls and extended anteriorly, 1.6-1.8 hd long and 63-79% cbd wide; four cephalic setae 3-4 µm long; circular amphids 6-9 µm in diameter; spicules straight but slightly bent at both ends; absence of gubernaculum and precloacal supplement.

  15. Two new species of Chromadoridae (Chromadorida: Nematoda) from the East China Sea.

    PubMed

    Huang, Yong; Gao, Qun

    2016-07-26

    Two new species of Chromadoridae, a family of free-living marine nematodes, are described from intertidal sediments of the East China Sea. Ptycholaimellus pirus sp. nov. is characterized by having a cuticle with six longitudinal rows of double dots and long somatic setae, relatively long cephalic setae, a pear-shaped terminal pharyngeal bulb occupying less than 30% of pharyngeal length, and an elongate conical tail. The new species is distinguished from all related species by the unique character of the cuticle, with six longitudinal rows of horizontal double dots, and the pear-shaped terminal pharyngeal bulb. Hypodontolaimus ventrapophyses sp. nov. is characterized by having a cylindrical body with a slightly expanded anterior end and a conical tail, a homogeneous cuticle with lateral differentiation of two longitudinal rows of larger dots, a well developed pharynx with oval-shaped buccal bulb and terminal bulb, and a large ventral gland. Males have slender, strongly curved spicules and a gubernaculum with a ventral apophysis, and precloacal supplements are absent. The new species differs from all related species in this genus by the structure of the gubernaculum, which has a ventral apophysis.

  16. Physical mechanisms for the offshore detachment of the Changjiang Diluted Water in the East China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Changsheng; Xue, Pengfei; Ding, Pingxing; Beardsley, R. C.; Xu, Qichun; Mao, Xianmou; Gao, Guoping; Qi, Jiahua; Li, Chunyan; Lin, Huichan; Cowles, Geoffrey; Shi, Maochong

    2008-02-01

    Physical mechanisms for the summertime offshore detachment of the Changjiang Diluted Water (CDW) into the East China Sea are examined using the high-resolution, unstructured-grid, Finite-Volume Coastal Ocean Model (FVCOM). The model results suggest that isolated low salinity water lens detected west of Cheju Island can be formed by (1) a large-scale adjustment of the flow field to the Changjiang discharge and (2) the detachment of anticyclonic eddies as a result of baroclinic instability of the CDW front. Adding the Changjiang discharge intensifies the clockwise vorticity of the subsurface current (originating from the Taiwan Warm Current) flowing along the 50-m isobath and thus drives the low-salinity water in the northern coastal area of the Changjiang mouth offshore over a submerged plateau that extends toward Cheju Island. Given a model horizontal resolution of less than 1.0 km, the CDW front becomes baroclinically unstable and forms a chain of anticyclonic and cyclonic eddies. The offshore detachment of anticyclonic eddies can carry the CDW offshore. This process is enhanced under northward winds as a result of the spatially nonuniform interaction of wind-induced Ekman flow and eddy-generated frontal density currents. Characteristics of the model-predicted eddy field are consistent with previous theoretical studies of baroclinic instability of buoyancy-driven coastal density currents and existing satellite imagery. The plume stability is controlled by the horizontal Ekman number. In the Changjiang, this number is much smaller than the criterion suggested by a theoretical analysis.

  17. Aridity over a semiarid zone in northern China and responses to the East Asian summer monsoon

    NASA Astrophysics Data System (ADS)

    Zhang, Hongli; Zhang, Qiang; Yue, Ping; Zhang, Liang; Liu, Qian; Qiao, Shaobo; Yan, Pengcheng

    2016-12-01

    In this study, the variability of the aridity over a semiarid zone in Northern China from 1961 to 2013 and its association with the northernmost margin of the East Asian summer monsoon (EASM) and its intensity were investigated using composite analysis, correlative analysis, and unrotated and rotated empirical orthogonal function analyses. The results indicate that a nonsignificant drying trend (0.03/10 years) occurs over the entire eastern semiarid zone, accompanied by a southward retreat in the northernmost margin of the EASM (0.24°/10 years), and that drying (0.11/10 years) and southward retreat (0.28°/10 years) are most obvious on the Loess Plateau. The response of the annual variation of aridity to changes in the northernmost margin of the EASM is also compared with its responses to changes in the intensity of the EASM; the results indicate that it is more related to the former, especially over the Loess Plateau. Furthermore, an abnormal aridity event is likely to occur over the Loess Plateau in a year when the EASM margin advances to its northernmost latitude abnormally ahead of time and retreats abnormally ahead of time compared to the mean state.

  18. A new species of Parodontophora (Nematoda: Axonolaimidae) from the intertidal zone of the East China Sea

    NASA Astrophysics Data System (ADS)

    Wang, Haixia; Huang, Yong

    2016-02-01

    This study described a new species of free-living nematode discovered in the intertidal mudflat of Ximen Island, East China Sea. The new species, designated Parodontophora longiamphidata sp. nov., was characterized by a cylindrical body with tapering extremeties; cuticle smooth without somatic setae; four short cephalic setae; cylindrical buccal cavity with six clawlike teeth at the top of stoma; pharynx cylindrical with widened base; amphidial fovea crook-shaped with elongated scalariform branch extending past level of base of pharynx and ventral gland; ventral gland cell long-oval shaped located posterior to pharyngo-intestinal junction; excretory pore at level of middle of buccal cavity; tail conico-cylindrical with enlarged tip; three caudal gland cells, male spicules arched with cephalic proximal end and tapered distal end; gubernaculum with dorso-caudal apophysis; female with two opposed outstretched ovaries; and vulva at slightly post-midpoint of body length. This new species was close to P. wuleidaowanensis Zhang, 2005 and P. polita Gerlach, 1955 in terms of long amphidial fovea branch. The newly found species was easily distinguishable from the two documented; its amphidial fovea branch (255-290 µm versus 72-106 and 125-150 µm) was obviously longer. Key to the Parodontophora species with a longer amphidial fovea branch was given.

  19. Auditing the Immunization Data Quality from Routine Reports in Shangyu District, East China

    PubMed Central

    Hu, Yu; Zhang, Xinpei; Li, Qian; Chen, Yaping

    2016-01-01

    Objective: To evaluate the immunization data quality in Shangyu District, East China. Methods: An audit for immunization data for the year 2014 was conducted in 20 vaccination clinics of Shangyu District. The consistency of immunization data was estimated by verification factors (VFs), which was the proportion of vaccine doses reported as being administered that could be verified by written documentation at vaccination clinics. The quality of monitoring systems was evaluated using the quality index (QI). Results: The VFs of 20 vaccine doses ranged from 0.94 to 1.04 at the district level. The VFs for the 20 vaccination clinics ranged from 0.57 to 1.07. The VFs for Shangyu District was 0.98. The mean of total QI score of the 20 vaccination clinics was 80.32%. A significant correlation between the VFs of the 3rd dose of the diphtheria–tetanus–pertussis combined vaccine (DTP) and QI scores was observed at the vaccination clinic level. Conclusions: Deficiencies in data consistency and immunization reporting practice in Shangyu District were observed. Targeted measures are suggested to improve the quality of the immunization reporting system in vaccination clinics with poor data consistency. PMID:27869729

  20. Aerosol deposition favors red tide phytoplankton in the East China Sea

    NASA Astrophysics Data System (ADS)

    Mackey, K. R.; Chien, C.; Chen, Y.; Glover, D. M.; Paytan, A.

    2013-12-01

    Chinese marginal seas support vast fisheries and vital economies, but their productivity is threatened by eutrophication from runoff and atmospheric deposition. The East China Sea is inundated with nitrogen from the Yangtze River and anthropogenic emissions, leading to elevated N:P ratios. We show that aerosol additions approximating one week of moderate deposition to offshore waters favor the growth of red tide phytoplankton, such as Skeletonema costatum, by providing nutrients and trace metals (iron and zinc) needed for growth. In contrast toxin-producing Pseudonitzchia does not benefit from aerosols in this region, possibly due to its preference for lower N:P ratios. A dose-dependent toxic response was observed in Synechococcus at high aerosol loads approximating a week of heavy deposition in the region. In contrast, phytoplankton growth at an onshore station was light limited, and aerosol additions did not have an appreciable effect on phytoplankton growth. Aerosol and chlorophyll observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite have the potential to explore the effect of aerosols on phytoplankton blooms over longer time scales and seasons. This study shows the potential for aerosols to control N:P ratios in offshore waters and to shape the phytoplankton community through fertilization and toxicity, contributing to the occurrence of red tides.

  1. Diversity of Cronobacter spp. isolates from the vegetables in the middle-east coastline of China.

    PubMed

    Chen, Wanyi; Yang, Jielin; You, Chunping; Liu, Zhenmin

    2016-06-01

    Cronobacter spp. has caused life-threatening neonatal infections mainly resulted from consumption of contaminated powdered infant formula. A total of 102 vegetable samples from retail markets were evaluated for the presence of Cronobacter spp. Thirty-five presumptive Cronobacter isolates were isolated and identified using API 20E and 16S rDNA sequencing analyses. All isolates and type strains were characterized using enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR), and genetic profiles of cluster analysis from this molecular typing test clearly showed that there were differences among isolates from different vegetables. A polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) based on the amplification of the gyrB gene (1258 bp) was developed to differentiate among Cronobacter species. A new PCR-RFLP assay based on the amplification of the gyrB gene using Alu I and Hinf I endonuclease combination is established and it has been confirmed an accurate and rapid subtyping method to differentiate Cronobacter species. Sequence analysis of the gyrB gene was proven to be suitable for the phylogenetic analysis of the Cronobacter strains, which has much better resolution based on SNPs in the identification of Cronobacter species specificity than PCR-RFLP and ERIC-PCR. Our study further confirmed that vegetables are one of the most common habitats or sources of Cronobacter spp. contamination in the middle-east coastline of China.

  2. Geologic evolution and aspects of the petroleum geology of the northern East China Sea shelf basin

    SciTech Connect

    Lee, G.H.; Kim, B.Y.; Shin, K.S.; Sunwoo, D.

    2006-02-15

    Analysis of multichannel seismic reflection profiles reveals that the northern East China Sea shelf basin experienced two phases of rifting, followed by regional subsidence. The initial rifting in the Late Cretaceous created a series of grabens and half grabens, filled by alluvial and fluviolacustrine deposits. Regional uplift and folding (Yuquan movement) in the late Eocene-early Oligocene terminated the initial rifting. Rifting resumed in the early Oligocene, while alluvial and fluviolacustrine deposition continued to prevail. A second phase of uplift in the early Miocene terminated the rifting, marking the transition to the postrift phase. The early postrift phase (early Miocene-late Miocene) is characterized by regional subsidence and westward and northwestward marine transgression. Inversion (Longjing movement) in the late Miocene interrupted the postrift subsidence, resulting in an extensive thrust-fold belt in the eastern part of the area. The entire area entered a stage of regional subsidence again and has become a broad continental shelf. Source rocks include synrift lacustrine facies, fluvial shales, and coal beds. Synrift fluvial, lacustrine, and deltaic deposits, postrift littoral and/or shallow-marine sandstones, and fractured basement have the potential to provide reservoirs. Various types of hydrocarbon traps (e.g., faulted anticlines, overthrusts, rollover anticlines, faults, unconformity traps, combination structural-stratigraphic traps, weathered basement, and stratigraphic traps) are recognized, but many of these traps have not been tested.

  3. Kuroshio subsurface water feeds the wintertime Taiwan Warm Current on the inner East China Sea shelf

    NASA Astrophysics Data System (ADS)

    Lian, Ergang; Yang, Shouye; Wu, Hui; Yang, Chengfan; Li, Chao; Liu, James T.

    2016-07-01

    The Taiwan Warm Current (TWC) has an overwhelming influence on the heat, salt, and nutrients balance on one of the broadest shelf in the world, the East China Sea shelf. In winter, the TWC flows in an unusual upwind direction and reaches the Changjiang (Yangtze River) Estuary, but its origin and pathway are intensely debated. Here combined evidences from current measurement, hydrographic, and stable isotopic data all suggest that the wintertime TWC intrusion off the Changjiang Estuary mainly originates from the Kuroshio subsurface water northeast of Taiwan, rather than from the Taiwan Strait warm water. The Kuroshio-branched water northeast of Taiwan can intrude into the inner shelf near the Zhe-Min Coast via bottom layer, manifesting by a pronounced boundary at 50 m isobath around 28°N, and thereby feeds the TWC intrusion into the Changjiang Estuary. The intrusion complicates the hydrological process in the estuary and shelf sea, and its impact on marine environment deserves more research attentions.

  4. Using rare earth elements to constrain particulate organic carbon flux in the East China Sea

    PubMed Central

    Hung, Chin-Chang; Chen, Ya-Feng; Hsu, Shih-Chieh; Wang, Kui; Chen, Jian Feng; Burdige, David J.

    2016-01-01

    Fluxes of particulate organic carbon (POC) in the East China Sea (ECS) have been reported to decrease from the inner continental shelf towards the outer continental shelf. Recent research has shown that POC fluxes in the ECS may be overestimated due to active sediment resuspension. To better characterize the effect of sediment resuspension on particle fluxes in the ECS, rare earth elements (REEs) and organic carbon (OC) were used in separate two-member mixing models to evaluate trap-collected POC fluxes. The ratio of resuspended particles from sediments to total trap-collected particles in the ECS ranged from 82–94% using the OC mixing model, and 30–80% using the REEs mixing model, respectively. These results suggest that REEs may be better proxies for sediment resuspension than OC in high turbidity marginal seas because REEs do not appear to undergo degradation during particle sinking as compared to organic carbon. Our results suggest that REEs can be used as tracers to provide quantitative estimates of POC fluxes in marginal seas. PMID:27670426

  5. Microbial biomarkers from the East China Sea and implications for paleoenvironmental reconstructions

    NASA Astrophysics Data System (ADS)

    Zhao, M.; Hu, W. J.; Duan, S. S.; Cao, L. Y.; Wang, Y. Y.; Zhao, S. Z.; Xing, L.

    2015-12-01

    We report the vertical and spatial distributions of isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs), ladderanes and phytoplankton biomarkers in suspended particulates from the East China Sea (ECS) to evaluate the living habitat and environments of the planktonic archaea Thaumarchaeota and anaerobic ammonium oxidation (anammox) bacteria, respectively. Maximum GDGT concentration mostly occurred in bottom waters while maximum phytoplankton biomarker concentration occurred in the surface layers; and these results from the ECS provides further evidence for the use of the TEX86 index as a proxy for bottom water temperature in shallow shelf sea environments. Ladderanes were detected in both surface and subsurface particulates, suggesting that anammox activity was widespread in both the hypoxia zone near the Changjiang Estuary and in the mid-shelf of the ECS. Thus, anaerobic condition is not a requirement for anammox bacteria; however, ladderane-derived anammox activity was higher in lower oxygen environments, confirming ladderanes as useful proxies for reconstructing hypoxia changes. Statistical analysis will be presented to assess the link between archaea (Thaumarchaeota) performing aerobic ammonia oxidation and bacteria (anammox) performing anaerobic ammonium oxidation in the ECS, the implications for both carbon and nitrogen cycles.

  6. Atmospheric front over the East China Sea studied by multisensor satellite and in situ data

    NASA Astrophysics Data System (ADS)

    Ivanov, Andrei Y.; Alpers, Werner; Litovchenko, Konstantin T.; He, Ming-Xia; Feng, Qian; Fang, Mingqiang; Yan, Xiao-Hai

    2004-12-01

    A frontal feature visible on a synthetic aperture radar (SAR) image acquired by the Radarsat satellite over the East China Sea on 19 November 2000 is analyzed in conjunction with data acquired by Quikscat, TOPEX/Poseidon, Tropical Rain Measurement Mission (TRMM), Defense Meteorological Satellite Program (DMSP), and National Oceanic and Atmospheric Administration (NOAA) satellites, and with data obtained from ship measurements. Although this frontal feature is located close to the Kuroshio front, it is demonstrated that it is not a sea surface manifestation of an oceanic front, but rather of an atmospheric front extending over 800 km from an area of the Pacific Ocean northeast of Taiwan to the southern coast of Korea. It is a cold front moving in the southeast direction with a speed of approximately 45-50 km/hour and associated with a 40-km-wide rainband trailing the front. The Radarsat image, which has a resolution of 50 m, reveals fine-scale structures of the atmospheric front, in particular small-scale convective rain cells embedded in the front. Conclusion is drawn that accurate interpretation of frontal features in SAR images requires use of additional meteorological and remote sensing data and information.

  7. Determinants of Childhood Immunization Uptake among Socio-Economically Disadvantaged Migrants in East China

    PubMed Central

    Hu, Yu; Li, Qian; Chen, Enfu; Chen, Yaping; Qi, Xiaohua

    2013-01-01

    Objective: To determine the coverage of childhood immunization appropriate for age among socio-economically disadvantaged recent migrants living in East China and to identify the determinants of full immunization uptake among these migrant children. Methods: This is a cross-sectional survey of 1,426 migrant mothers with a child aged ≤24 months, who were interviewed with a pretested questionnaire. Various vaccines, migration history and some other social-demographic and income details were collected. Single-level logistic regression analyses were applied to identify the determinants of full immunization status. Results: Immunization coverage rates are lower among migrants and even lower among recent migrants. The likelihood of a child receiving full immunization rise with parents’ educational level and the frequency of mother’s utilization of health care. Higher household income also significantly increase the likelihood of full immunization, as dose post-natal visits by a health worker. Conclusions: Recent migrant status favours low immunization uptake, particularly in the vulnerability context of alienation and livelihood insecurity. Services must be delivered with a focus on recent migrants. Investments are needed in education, socio-economic development and secure livelihoods to improve and sustain equitable health care services. PMID:23839061

  8. Effects of an artificial oyster shell reef on macrobenthic communities in Rongcheng Bay, East China

    NASA Astrophysics Data System (ADS)

    Xu, Qinzeng; Zhang, Libin; Zhang, Tao; Zhou, Yi; Xia, Sudong; Liu, Hui; Yang, Hongsheng

    2014-01-01

    An artificial oyster shell reef was deployed in Rongcheng Bay, East China. However, the effects of this reef on the surrounding macrobenthic communities were unknown. We compared sedimentary factors, macrobenthic biomass, abundance, and community composition and ecological indicators between the reef and non-reef areas over a one year period. The mean values for chlorophyll a (Chl a), total organic matter (TOM), total organic carbon (TOC), and total nitrogen (TN) content in surface sediments in the reef area were slightly higher than those in the non-reef area. The Chl a levels differed significantly between the two areas, but the TOM, TOC, and TN were not significantly different. The abundance of crustaceans was significantly different between the two areas, but the abundance and biomass of polychaetes, echinoderms, mollusk did not differ significantly. The permutational multivariate analysis of variance (PERMANOVA) revealed that the macrobenthic community differed significantly through time and analysis of similarity multivariate analyses (ANOSIM) revealed that the macrobenthic community differed significantly in some months. The ecological indicators revealed that the environmental quality of the reef area was slightly better than that of the non-reef area. Overall, our results suggest that the artificial oyster shell reef may change the macrobenthic community and the quality of the environment. Despite the lack of an effect in the short term, long-term monitoring is still needed to evaluate the effects of artificial oyster shell reefs on macrobenthic communities.

  9. Oceanic influence on the Baiu frontal zone in the East China Sea

    NASA Astrophysics Data System (ADS)

    Kunoki, Shiori; Manda, Atsuyoshi; Kodama, Yasu-Masa; Iizuka, Satoshi; Sato, Kazutoshi; Fathrio, Ibnu; Mitsui, Taku; Seko, Hiromu; Moteki, Qoosaku; Minobe, Shoshiro; Tachibana, Yoshihiro

    2015-01-01

    high-resolution transect of atmospheric soundings across the Kuroshio Current in the East China Sea was conducted onboard a ship in June 2012 with the objective of analyzing the influence of the complex sea surface temperature (SST) distribution on the Baiu frontal zone (BFZ). Expendable bathythermograph castings and continuous surface meteorological observations were also examined. Two distinct mesoscale atmospheric fronts, characterized by changes of wind direction in the lower troposphere and surface air temperature, were found in the BFZ. One (northern) atmospheric front was observed around the SST front in relation to a warm water tongue extending from the Kuroshio. A high SST region around the northern atmospheric front enhances unstable near surface stratification and intensifies turbulent heat flux. They help modify the marine atmospheric boundary layer in the BFZ. The other (southern) atmospheric front was at the southern end of the BFZ. Intense evaporation over the Kuroshio and moisture transport by southerly winds were important in forming the conditionally unstable air masses in the lower troposphere of the BFZ.

  10. Characteristics of turbulent kinetic energy dissipation rate and turbidity near the coast of East China Sea

    NASA Astrophysics Data System (ADS)

    Zhang, Yanwei; Xu, Huiping; Qin, Rufu; Xu, Changwei; Fan, Daidu

    2016-09-01

    The East China Sea (ECS) has a high suspended-sediment concentration because of the influence of the Changjiang River, indicated by high turbidity in the water. Considering the islands offthe coast and the complex topography, and the strong influence of tides and wind, the coast offthe ECS is a typical region with strong oceanic mixing processes. The changes in the dynamic processes near the bottom play an important role in the control of water turbidity. The turbulent kinetic energy dissipation rate ( ɛ ) is a parameter that shows the strength of ocean mixing. This is estimated based on a structure method using current velocity that is measured by a high-frequency Acoustic Doppler Current Profiler (ADCP) from a seafloor observatory in the ECS. The results indicate strong ocean mixing processes with a mean ɛ value of 5.7×10-5 W/kg and distinct tidal variations in the dissipation rate. Conversely, the variation of the water turbidity leads to changes in the water dynamical structure near the bottom. Comparing the dissipation rate with the turbidity near the bottom boundary layer, we find that the high turbidity mimics strong ocean mixing.

  11. Reconstructing Late Holocene Climate Variability in North East China From Varved Maar Lake Sediments

    NASA Astrophysics Data System (ADS)

    Panizzo, V. N.; Mackay, A. W.; Rioual, P.; Chu, G.; Leng, M. J.

    2008-12-01

    Reconstructing climatic variability over the past c. 2 ka years is recognised as a key PAGES timeframe (focus 2). However few high-resolution records exist from the climate sensitive region of N) China which receives the majority of its precipitation from the east Asian summer monsoon (EASM). Interactions between the EASM and the global climate system have great resonance. Such examples include how the EASM responded to changes in climate over the documented e.g. "Medieval Warm Period" (c. AD 900 - 1300), "Little Ice Age" (c. AD 1350-1850) and recent warming. At present, literature remains contradictory to such environmental changes in NE China over this time-frame due to poor chronological control, low resolution of existing studies and even due to the inexact terminology of these climatic periods. Xiaolongwan Lake (XLW) is a small, closed, maar lake located in the Long Gang Volcanic Field, NE China (42°18'N; 126°19'E). It is at an elevation of 655 m a.s.l. with a maximum depth of 15 m. A varve chronology has been created for a 143 cm composite core (2 cores collected in 2006), and here we present diatoms and organic geochemistry (δ13C, TOC, C/N) evidence for environmental change over the past c. 2 ka years. Results show a gradual change in diatom species, moving from a composition where opportunistic species (e.g. Achnanthidium minutissimum) dominate (between c. 100 BC to 500 years AD) at the beginning of the record to one comprised of benthic/epiphytic species (e.g. Staurosira construens var venter, Punctastriata discoidea, Gomphonema parvulum). The introduction after c. 1850 years AD of the planktonic diatom species, Discotella woltereckii, not previously seen in the record, coincides with recent warming. This may be a response to changing limnological conditions, such as decreasing duration of lake ice-cover. Bulk organic δ13C results conducted on a short core collected from XLW in summer 2007, show that over the past c. 350 years there is a distinct

  12. Heterogeneity of hydraulic conductivity and Darcian flux in the submerged streambed and adjacent exposed stream bank of the Beiluo River, northwest China

    NASA Astrophysics Data System (ADS)

    Song, Jinxi; Jiang, Weiwei; Xu, Shaofeng; Zhang, Guotao; Wang, Liping; Wen, Min; Zhang, Bo; Wang, Yuanyuan; Long, Yongqing

    2016-12-01

    Recognizing the heterogeneity of hydraulic conductivity and hyporheic flow is critical for understanding contaminant transfer and biogeochemical and hydrological processes involving streams and aquifers. In this study, the heterogeneity of hydraulic conductivity and Darcian flux in a submerged streambed and its adjacent exposed stream banks were investigated in the Beiluo River, northwest China. In the submerged streambed, Darcian flux was estimated by measurement of vertical hydraulic conductivity ( K v) and vertical head gradient (VHG) using in-situ permeameter tests. On exposed stream banks, both horizontal hydraulic conductivity ( K h) and K v were measured by on-site permeameter tests. In the submerged streambed, K v values gradually decreased with depth and the higher values were concentrated in the center and close to the erosional bank. Compared to the exposed stream banks, the K v values were higher in the streambed. From stream stage to the topmost layer of tested sediment, through increasing elevation, the K h values increased on the erosional bank, while they decreased on the depositional bank. The values of VHG along the thalweg illustrate that downwelling flux occurred in the deepest area while upwelling flux appeared in the other areas, which might result from the change of streambed elevation. The higher value of the Darcian flux in the submerged streambed existed near the erosional bank.

  13. Impact of temperature variation between adjacent days on childhood hand, foot and mouth disease during April and July in urban and rural Hefei, China

    NASA Astrophysics Data System (ADS)

    Cheng, Jian; Zhu, Rui; Xu, Zhiwei; Wu, Jinju; Wang, Xu; Li, Kesheng; Wen, Liying; Yang, Huihui; Su, Hong

    2016-06-01

    Previous studies have found that both high temperature and low temperature increase the risk of childhood hand, foot and mouth disease (HFMD). However, little is known about whether temperature variation between neighboring days has any effects on childhood HFMD. A Poisson generalized linear regression model, combined with a distributed lag non-linear model, was applied to examine the relationship between temperature change and childhood HFMD in Hefei, China, from 1st January 2010 to 31st December 2012. Temperature change was defined as the difference of current day's mean temperature and previous day's mean temperature. Late spring and early summer (April-July) were chosen as the main study period due to it having the highest childhood HFMD incidence. There was a statistical association between temperature change between neighboring days and childhood HFMD. The effects of temperature change on childhood HFMD increased below a temperature change of 0 °C (temperature drop). The temperature change has the greatest adverse effect on childhood HFMD at 7 days lag, with 4 % (95 % confidence interval 2-7 %) increase per 3 °C drop of temperature. Male children and urban children appeared to be more vulnerable to the effects of temperature change. Temperature change between adjacent days might be an alternative temperature indictor for exploring the temperature-HFMD relationship.

  14. Impact of temperature variation between adjacent days on childhood hand, foot and mouth disease during April and July in urban and rural Hefei, China.

    PubMed

    Cheng, Jian; Zhu, Rui; Xu, Zhiwei; Wu, Jinju; Wang, Xu; Li, Kesheng; Wen, Liying; Yang, Huihui; Su, Hong

    2016-06-01

    Previous studies have found that both high temperature and low temperature increase the risk of childhood hand, foot and mouth disease (HFMD). However, little is known about whether temperature variation between neighboring days has any effects on childhood HFMD. A Poisson generalized linear regression model, combined with a distributed lag non-linear model, was applied to examine the relationship between temperature change and childhood HFMD in Hefei, China, from 1st January 2010 to 31st December 2012. Temperature change was defined as the difference of current day's mean temperature and previous day's mean temperature. Late spring and early summer (April-July) were chosen as the main study period due to it having the highest childhood HFMD incidence. There was a statistical association between temperature change between neighboring days and childhood HFMD. The effects of temperature change on childhood HFMD increased below a temperature change of 0 °C (temperature drop). The temperature change has the greatest adverse effect on childhood HFMD at 7 days lag, with 4 % (95 % confidence interval 2-7 %) increase per 3 °C drop of temperature. Male children and urban children appeared to be more vulnerable to the effects of temperature change. Temperature change between adjacent days might be an alternative temperature indictor for exploring the temperature-HFMD relationship.

  15. Diversity and spatial distribution of sediment ammonia-oxidizing crenarchaeota in response to estuarine and environmental gradients in the Changjiang Estuary and East China Sea.

    PubMed

    Dang, Hongyue; Zhang, Xiaoxia; Sun, Jin; Li, Tiegang; Zhang, Zhinan; Yang, Guanpin

    2008-07-01

    Ammonia-oxidizing archaea (AOA) have recently been found to be potentially important in nitrogen cycling in a variety of environments, such as terrestrial soils, wastewater treatment reactors, marine waters and sediments, and especially in estuaries, where high input of anthropogenic nitrogen is often experienced. The sedimentary AOA diversity, community structure and spatial distribution in the Changjiang Estuary and the adjacent East China Sea were studied. Multivariate statistical analysis indicated that the archaeal amoA genotype communities could be clustered according to sampling transects, and the station located in an estuarine mixing zone harboured a distinct AOA community. The distribution of AOA communities correlated significantly with the gradients of surface-water salinity and sediment sorting coefficient. The spatial distribution of putative soil-related AOA in certain sampling stations indicated a strong impact of the Changjiang freshwater discharge on the marine benthic microbial ecosystem. Besides freshwater, nutrients, organic matter and suspended particles, the Changjiang Diluted Water might also contribute to the transport of terrestrial archaea into the seawater and sediments along its flow path.

  16. In situ study on photosynthetic characteristics of phytoplankton in the Yellow Sea and East China Sea in summer 2013

    NASA Astrophysics Data System (ADS)

    Li, Junlei; Sun, Xiaoxia; Zheng, Shan

    2016-08-01

    In situ studies on photosynthetic characteristics of phytoplankton were important for the analysis of changes in community structure and for the prediction and control of algal blooms, but such studies of phytoplankton in offshore China were few. In this study, the detailed distribution of photosynthetic characteristics of phytoplankton in the summer of 2013 in the Yellow Sea and East China Sea was measured using Phyto-PAM (Pulse Amplitude Modulation). The phytoplankton community structure and the environmental parameters were also investigated to estimate the relationship between the distribution of the photochemical competence of phytoplankton and ecological factors. The total average Fv/Fm (the potential maximum quantum yield) value of phytoplankton in the Yellow Sea and East China Sea in summer 2013 was less than 0.5, reflecting that the photosynthetic activity of phytoplankton was relatively low. Fv/Fm of phytoplankton in summer was significantly positively associated with nitrate content (NO2-), which reflects relationship between metabolism and photosynthesis of phytoplankton: accompanied by NO2- metabolism, photosynthesis and photosynthetic capacity may be enhanced simultaneously, so the Fv/Fm value would increase with the NO2- released by phytoplankton. Through the in situ study on photosynthetic characteristics of phytoplankton in the Yellow Sea and East China Sea, we come to the conclusion that photosynthetic characteristics and activity of phytoplankton are influenced by its biological characteristics and surrounding ecological factors, such as irradiance, nutrients and phytoplankton community. Meanwhile, the thermally stratified structure and the movement of water masses, such as the Yangtze River diluted water, the Yellow Sea cold water mass and other different water system, also have an important impact on phytoplankton photosynthetic activity and characteristics. Greater understanding of the detailed photosynthetic characteristics of phytoplankton

  17. Source attribution and process analysis for atmospheric mercury in East China simulated by CMAQ-Hg

    NASA Astrophysics Data System (ADS)

    Zhu, J.; Wang, T.; Bieser, J.; Matthias, V.

    2015-04-01

    The contribution from different emission sources and atmospheric processes to gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), particulate bound mercury (PBM) and mercury deposition in East China were quantified using the Community Multi-scale Air Quality (CMAQ-Hg) modeling system run with nested grid resolution of 27 km. Natural source (NAT) and six categories of anthropogenic mercury sources (ANTH) including cement production (CEM), domestic life (DOM), industrial boilers (IND), metal production (MET), coal-fired power plants (PP) and traffic (TRA) were considered for source apportionment. NAT was responsible for 36.6% of annual averaged GEM concentration which was regard as the most important source for GEM in spite of obvious seasonal variation. Among ANTH, the influence of MET and PP on GEM were most evident especially in winter. ANTH dominated the variations of GOM and PBM concentration with a contribution of 86.7 and 79.1% respectively. Among ANTH, IND was the largest contributor for GOM (57.5%) and PBM (34.4%) so that most mercury deposition came from IND. The effect of mercury emitted from out of China was indicated by > 30% contribution to GEM concentration and wet deposition. The contribution from nine processes consisting of emissions (EMIS), gas-phase chemical production/loss (CHEM), horizontal advection (HADV), vertical advection (ZADV), horizontal advection (HDIF), vertical diffusion (VDIF), dry deposition (DDEP), cloud processes (CLDS) and aerosol processes (AERO) were calculated for processes analysis with their comparison in urban and non-urban regions of Yangtze River Delta (YRD). EMIS and VDIF affected surface GEM and PBM concentration most and tended to compensate each other all the time in both urban and non-urban areas. However, DDEP was the most important removal process for GOM with 7.3 and 2.9 ng m-3 reduced in the surface of urban and non-urban areas respectively in a whole day. Diurnal profile variation of processes

  18. Hygroscopic behavior of water-soluble matter in marine aerosols over the East China Sea.

    PubMed

    Yan, Yu; Fu, Pingqing; Jing, Bo; Peng, Chao; Boreddy, S K R; Yang, Fan; Wei, Lianfang; Sun, Yele; Wang, Zifa; Ge, Maofa

    2017-02-01

    In this study, we investigated hygroscopic properties of water-soluble matter (WSM) in marine aerosols over the East China Sea, which were collected during a Natural Science Foundation of China (NSFC) sharing cruise in 2014. Hygroscopic growth factors (g) of WSM were measured by a hygroscopicity tandem differential mobility analyzer (H-TDMA) with an initial dry particle mobility diameter of 100nm. The observed g at 90% relative humidity (RH), g(90%)WSM, defined as the ratio of the particle diameter at 90% RH to that at RH<5% (initial dry diameter), ranged from 1.67 to 2.41 (mean±std: 1.99±0.23). The g values were lower than that of seawater (2.1) but comparable with those reported for marine aerosols (1.79-2.08). The H-TDMA retrieved hygroscopicity parameter of WSM, κWSM, ranged from 0.46 to 1.56 (0.88±0.35). The observed g(90%)WSM during the daytime ranged from 1.67 to 2.40 (1.95±0.21) versus 1.71 to 2.41 (2.03±0.26) during the nighttime. κWSM was 0.81±0.32 in the daytime and 0.95±0.40 in the nighttime. The day/night differences of g(90%)WSM and κWSM indicated that nighttime marine aerosols were more hygroscopic than those in daytime, which was likely related to enhanced heterogeneous reaction of ammonium nitrate in nighttime and the higher Cl(-)/Na(+) molar ratios obtained (0.80) in nighttime than those (0.47) in daytime. Inorganic ions accounted for 72-99% of WSM with SO4(2-) being the dominant species, contributing to 47% of the total inorganic ion mass. The declined g(90%) comparing with sea water was likely due to the transport of anthropogenic aerosols, chemical aging of dust particles, the contribution of biomass burning products, and the aerosol hygroscopic growth inhibition of organics.

  19. [Phytoplankton assemblages on the continental shelf of East China Sea in autumn 2006].

    PubMed

    Wang, Dan; Sun, Jun; An, Bai-zheng; Ni, Xiao-bo; Liu, Su-mei

    2008-11-01

    Based on the survey from November 19 to December 24, 2006, the species composition, assemblage structure, and cell abundance of phytoplankton on the continental shelf of East China Sea (24.0 degrees N- 32.0 degrees N, 120.0 degrees - 128.0 degrees E) were studied. The phytoplankton flora in the survey area included 145 taxa, belonging to 64 genera of 4 classes (including uncertain species). Bacillariophyta was the dominant functional group, followed by Pyrrophyta. The dominant species in turn were Thalassionema nitzschioides, Thalassiosira rotula, Leptocylindrus danicus, Guinardia striata, Pseudo-nitzschia pungens, and Trichodesmium thiebautii. The cell abundance of the phytoplankton ranged from 0.09 to 35.11 cells x ml(-1), with an average of 4.92 cells x ml(-1). In the autumn, Bacillariophyta abundance discriminated the surface pattern of the phytoplankton, and the higher abundance area was located at the northeast part of offshore regions, with the cell abundance reached 30 cells x ml(-1). On the whole, the cell abundance of Bacillariophyta and Pyrrophyta was concentrated in surface water, and it reduced rapidly from surface layer down to the bottom. According to the section distribution, the phytoplankton mainly concentrated in surface water, and also, in the middle and bottom layers for some stations. The average of Shannon-Wiener indices of phytoplankton assemblage was 2.80, with the higher values occurred in the northeast and southeast of the survey area. The average of Pielou' s evenness of phytoplankton assemblage was 0.81, and the higher value was located at the middle of the survey area. The surface horizontal distribution of Shannon-Wiener indices was coincided with that of phytoplankton cell abundance. According to the Pearson correlation analysis, the factors that significantly affected the growth of the phytoplankton were nitrite, dissolved organic nitrogen (DON), and temperature.

  20. [Phytoplankton community structure in Shijiuyang constructed wetland of Jiaxing, Zhejiang Province of east China in winter].

    PubMed

    Zhang, Wei; Wang, Wei-dong; Wang, Li-qing; Zhang, Rui-lei; Chen, Qing-hua

    2011-09-01

    Aimed to explore the purification effect of constructed wetland on phytoplankton community structure, an investigation was conducted on the species composition, biomass, and community diversity of phytoplankton in the water body of Shijiuyang constructed drinking water source wetland of Jiaxing, Zhejiang Province of East China in winter, 2010. A total of 77 phytoplankton species were identified, belonging to 39 genera of 7 phyla. The main phylum was Bacillariophyta, with 33 species of 14 genera. The dominant species were Melosira varians, Cyclotella meneghiniana, Nitzschia sp., Chroococcus sp., Dactylococcopsis rhaphidioides, Scendesmus quadricauda, and Tribonema bombycium, among which, C. meneghiniana had the highest dominance (0.144). The phytoplankton density in winter was averagely 1.28 x 10(6) cell x L(-1), with the minimum (6.80 x 10(5) cell x L(-1)) in the water outlet, and the density of Cyanophyta in the water outlet was significantly lower than that in the water inlet (P < 0.05), only occupying 14.9% of the latter. The Shannon index of the phytoplankton community at the sampling sites ranged from 0.94 to 1.27. According to the cluster analysis and multidimensional scaling (MDS), the phytoplankton community was classified into five phytoplankton community groups, i.e., root-channels littoral community, root-channels flow community (2 styles), highly purified area community, and headwater region community. Diverse ecological environment and water flow velocity at the sampling sites were found to be the main contributors to the formation of the five phytoplankton community groups.

  1. [Litter decomposition and its main affecting factors in tidal marshes of Minjiang River Estuary, East China].

    PubMed

    Zhang, Lin-Hai; Zeng, Cong-Sheng; Zhang, Wen-Juan; Wang, Tian-E; Tong, Chuan

    2012-09-01

    By using litterbag method, this paper studied the decomposition of the leaf- and flower litters of two emergent macrophytes, native species Phragmites australis and invasive species Spartina alterniflora, and related affecting factors in the Minjiang River estuary of East China. In the decomposition process of the litters, the decay of standing litter (0-90 days) was an important period, and the loss rate of the flower- and leaf litters dry mass of P. australis and S. alterniflora was 15.0 +/- 3.5% and 13.3 +/- 1.1%, and 31.9 +/- 1.1% and 20.8 +/- 1.4%, respectively. During lodging decay period (91-210 days), the loss rate of the flower- and leaf litters dry mass of P. australis and S. alterniflora was 69.5 +/- 0.6% and 71.5 +/- 2.5%, and 76.8 +/- 1.9% and 67.5 +/- 2.1%, respectively. In standing decay period, the decomposition rate of the two plants litters was positively correlated with the litters C/N but negatively correlated to the litters N/P, and the litters P was an important factor limiting the litters decay. In lodging decay period, the effects of the litters C/N, C/P, and N/P decreased, while the environment factors (climate, soil moisture, soil acidity and salinity, and sediment properties) acted more important roles. The differences in the factors affecting the decay of the litters in different decomposition periods were mainly related to the micro-environment and tidal process for the two plant communities.

  2. Effects of aerosol-radiation interaction on precipitation during biomass-burning season in East China

    NASA Astrophysics Data System (ADS)

    Huang, Xin; Ding, Aijun; Liu, Lixia; Liu, Qiang; Ding, Ke; Niu, Xiaorui; Nie, Wei; Xu, Zheng; Chi, Xuguang; Wang, Minghuai; Sun, Jianning; Guo, Weidong; Fu, Congbin

    2016-08-01

    Biomass burning is a main source for primary carbonaceous particles in the atmosphere and acts as a crucial factor that alters Earth's energy budget and balance. It is also an important factor influencing air quality, regional climate and sustainability in the domain of Pan-Eurasian Experiment (PEEX). During the exceptionally intense agricultural fire season in mid-June 2012, accompanied by rapidly deteriorating air quality, a series of meteorological anomalies was observed, including a large decline in near-surface air temperature, spatial shifts and changes in precipitation in Jiangsu province of East China. To explore the underlying processes that link air pollution to weather modification, we conducted a numerical study with parallel simulations using the fully coupled meteorology-chemistry model WRF-Chem with a high-resolution emission inventory for agricultural fires. Evaluation of the modeling results with available ground-based measurements and satellite retrievals showed that this model was able to reproduce the magnitude and spatial variations of fire-induced air pollution. During the biomass-burning event in mid-June 2012, intensive emission of absorbing aerosols trapped a considerable part of solar radiation in the atmosphere and reduced incident radiation reaching the surface on a regional scale, followed by lowered surface sensible and latent heat fluxes. The perturbed energy balance and re-allocation gave rise to substantial adjustments in vertical temperature stratification, namely surface cooling and upper-air heating. Furthermore, an intimate link between temperature profile and small-scale processes like turbulent mixing and entrainment led to distinct changes in precipitation. On the one hand, by stabilizing the atmosphere below and reducing the surface flux, black carbon-laden plumes tended to dissipate daytime cloud and suppress the convective precipitation over Nanjing. On the other hand, heating aloft increased upper-level convective

  3. Preliminary results of new surface heat flow measurements in the northern East China Sea

    NASA Astrophysics Data System (ADS)

    Kim, Young-Gyun

    2013-04-01

    Conventional heat flow measurements using a marine heat probe have been rarely carried out in the shallow seas. This is generally because 1) strong bottom-water temperature variation (BTV) which significantly affects temperature distribution in the top few meters of sediments hides the background geothermal gradient generated by conductive heat from deep in Earth, and 2) coarse surficial lithology which prevents the heat probe from being penetrated enough into the sediments is prevalent. In the northern East China Sea, there is few surface heat flow data due to such harsh conditions. The sea experiences seasonal flux change of Kuroshio and Taiwan Warm currents and large amount of sediment discharge from Yangtze River. New heat flow measurements using a Ewing-type heat probe were made at 11 sites with water depths of 57-120 mbsl in December 2012. For the successive penetration of the probe, areas of the finer surficial lithology were carefully chosen as target sites based on core samples using a gravity corer as well as Chirp survey results. Also, length and weight of the heat probe were adjusted to 3 meter with 7 thermistors and ~450 kg, respectively. As a result, the heat probe nearly vertically penetrated up to its full length into the sediments. Observed temperatures at depths are not fitted into a linear line, and show overall inversion with local maximum value at the middle depths. These are clear evidences of temperature disturbance by BTV. Due to lack of information, BTV is roughly approximated based on available bottom-water temperature data in the vicinity of the study area. After removal of BTV effects, the observed temperatures are nearly aligned into a line, indicating that conductive cooling is dominant heat transfer process in this region. Accordingly, the background geothermal gradient is estimated as 20-30 mK/m comparable with results from wells around the study area.

  4. Oceanic response to Typhoon Nari (2007) in the East China Sea

    NASA Astrophysics Data System (ADS)

    Oh, Kyung-Hee; Lee, Seok; Kang, Sok-Kuh; Song, Kyu-Min

    2017-02-01

    The oceanic response to a typhoon in the East China Sea (ECS) was examined using thermal and current structures obtained from ocean surface drifters and a bottom-moored current profiler installed on the right side of the typhoon's track. Typhoon Nari (2007) had strong winds as it passed the central region of the ECS. The thermal structure in the ECS responded to Typhoon Nari (2007) very quickly: the seasonal thermocline abruptly collapsed and the sea surface temperature dropped immediately by about 4°C after the typhoon passed. The strong vertical mixing and surface cooling caused by the typhoon resulted in a change in the thermal structure. Strong near-inertial oscillation occurred immediately after the typhoon passed and lasted for at least 4-5 days, during which a strong vertical current existed in the lower layer. Characteristics of the near-inertial internal oscillation were observed in the middle layer. The clockwise component of the inertial frequency was enhanced in the surface layer and at 63 m depth after the typhoon passed, with these layers almost perfectly out of phase. The vertical shear current was intensified by the interaction of the wind-driven current in the upper layer and the background semi-diurnal tidal current during the arrival of the typhoon, and also by the near-inertial internal oscillation after the typhoon passage. The strong near-inertial internal oscillation persisted without significant interfacial structure after the mixing of the thermocline, which could enhance the vertical mixing over several days.

  5. [Geochemical distribution of dissolved bismuth in the Yellow Sea and East China Sea].

    PubMed

    Wu, Xiao-Dan; Song, Jin-Ming; Wu, Bin; Li, Xue-Gang

    2014-01-01

    Occurrence level, geochemical distribution of dissolved bismuth and its coupling relationship to eco-environment were investigated in the Yellow Sea and East China Sea to explore the source and influencing factors. The results showed that the concentration of dissolved bismuth was within the range of 0-0. 029 microg x L(-1) at the surface and 0.001-0.189 microg x L(-1) at the bottom, with the averages of 0.008 and 0.016 microg x L(-1), respectively. Horizontally, low value of dissolved bismuth exhibited the bidirectional extension feature, indicating that it could trace the path of Changjiang Diluted Water. High value of dissolved bismuth was observed where the Subei Costal Current and Yellow Sea Warm Current flowed and the Changjiang Diluted Water and Zhejiang-Fujian Coastal Current met, suggesting that it was controlled by the cycle of current system. Vertically, the coastal water was fully mixed by water convection and eddy mixing, and was divided from the stratified water by strong tidal front, which blocked the transport of dissolved bismuth to the open sea. Thus, the concentration in front area was significantly higher than that in the open sea. Diurnal variation of dissolved bismuth was related to the hydrodynamic conditions (tide, suspension and thermocline) instead of the environmental factors (temperature and salinity). Positive relationship to SPM (suspended particulate matter) clarified that bismuth was prone to release from solid phase to liquid phase. Furthermore, conditions with temperature ranging 22-27 degrees C, salinity ranging 28-31 and pH ranging 7.9-8.1 were shown to be optimal for the release process.

  6. The response of the East China Sea to the Typhoon Ewiniar 2006

    NASA Astrophysics Data System (ADS)

    Kang, H.; Jung, K.; Kang, S.; Soh, J.; Shim, J.

    2007-05-01

    Response of the upper ocean to the typhoon Ewiniar 2006 in the northern East China Sea (ECS) has been investigated using observations at Ieodo Ocean Research Station (IORS) and TRMM Microwave Imager (TMI) data. Typhoon Ewiniar 2006 lasted about twelve days since it was born near the Micronesia in the Western Pacific. It moved generally northward and it was less than two days on the ECS until it made a landfall on the western region of Korea. Evidences of the interaction between the typhoon Ewiniar and the ECS have been found at the data gathered IORS, especially when the distance between the Ewiniar and IORS was shortest (less than 70 km). The water temperature drop in the upper layer was very large as much as about 9 - 10 ° C during 15 hours. The TMI sea surface temperature supports this evidence showing about 7.6 ° C drop of the water temperature during a day. Though the cooling of upper ECS seems to be happened along the entire Ewiniar track in the ECS, the temperature drop range was not as high as at the IORS. Waters around ECS shelf near to the IORS affected much more because of relatively shallow water depth with thin mixed layer as well as cold and relatively saline bottom waters underlying it. It should be noted that this strong influence of the typhoon Ewiniar on the ECS shelf plays a negative feedback to the Ewiniar intensity resulting in rapid weakening of its strength. The interaction between the Ewiniar and the waters around the IORS is larger than other ECS area could be explained by the relatively low translation speed of the typhoon Ewiniar.

  7. Performance evaluation of operational atmospheric correction algorithms over the East China Seas

    NASA Astrophysics Data System (ADS)

    He, Shuangyan; He, Mingxia; Fischer, Jürgen

    2017-01-01

    To acquire high-quality operational data products for Chinese in-orbit and scheduled ocean color sensors, the performances of two operational atmospheric correction (AC) algorithms (ESA MEGS 7.4.1 and NASA SeaDAS 6.1) were evaluated over the East China Seas (ECS) using MERIS data. The spectral remote sensing reflectance R rs(λ), aerosol optical thickness (AOT), and Ångström exponent (α) retrieved using the two algorithms were validated using in situ measurements obtained between May 2002 and October 2009. Match-ups of R rs, AOT, and α between the in situ and MERIS data were obtained through strict exclusion criteria. Statistical analysis of R rs(λ) showed a mean percentage difference (MPD) of 9%-13% in the 490-560 nm spectral range, and significant overestimation was observed at 413 nm (MPD>72%). The AOTs were overestimated (MPD>32%), and although the ESA algorithm outperformed the NASA algorithm in the blue-green bands, the situation was reversed in the red-near-infrared bands. The value of α was obviously underestimated by the ESA algorithm (MPD=41%) but not by the NASA algorithm (MPD=35%). To clarify why the NASA algorithm performed better in the retrieval of α, scatter plots of the α single scattering albedo (SSA) density were prepared. These α-SSA density scatter plots showed that the applicability of the aerosol models used by the NASA algorithm over the ECS is better than that used by the ESA algorithm, although neither aerosol model is suitable for the ECS region. The results of this study provide a reference to both data users and data agencies regarding the use of operational data products and the investigation into the improvement of current AC schemes over the ECS.

  8. Vertical distribution of pigmented and non-pigmented nanoflagellates in the East China Sea

    NASA Astrophysics Data System (ADS)

    Tsai, Sheng-Fang; Lin, Fan-Wei; Chan, Ya-Fan; Chiang, Kuo-Ping

    2016-08-01

    Nanoflagellates can be separated into two groups according to their trophic mode, i.e. pigmented nanoflagellates (PNF) and heterotrophic nanoflagellates (HNF). However, a newly identified group, mixotrophic nanoflagellates (MNF), are pigmented and show the ability of prey on bacteria. To examine the vertical variations in PNF and HNF abundances, as well as their relationships and the nutritional strategies that they might use, two summer cruises were undertaken in the East China Sea in July 2011 (OR1 966) and July 2012 (OR1 1004). The results show that both HNF and PNF abundances decline with increasing water depth. Vertical variations of abundances are believed to be influenced by prey and light, for HNF and PNF respectively. Over a large part of the sampling area, the ratio of PNF to HNF abundances is about 1:1 in the disphotic and euphotic zones, but exceeds 1.5 in the nutrient-depleted environment along the margin of the continental shelf. The correlation between PNF abundance and bacteria/Synechococcus abundance is positive where PNF/HNF >1.5. However, there is no significant correlation between PNF/HNF abundance when PNF/HNF >1.5 and light/nutrients, indicating that vertical distributions are influenced mainly by prey (bacteria and Synechococcus) in the nutrient-depleted environment. This study assumes that PNF consists mostly of MNF. In the euphotic zone they receive energy from photosynthesis, which is stimulated by the available nutrients from grazing. Their abundance is thus higher than that of HNF. However, in the disphotic zone, both PNF and HNF satisfy their nutrient demands by grazing, and PNF/HNF is close to 1. In other words, mixotrophy might be the main trophic mode for PNF in the nutrient-depleted, oligotrophic environment. Meanwhile, in deeper water (300 m), the much lower prey density means that MNF cannot satisfy the basic energy demands of metabolism and photosynthesis, and thus HNF abundance exceeds that of PNF.

  9. Hydrodynamic condition and suspended sediment diffusion in the Yellow Sea and East China Sea

    NASA Astrophysics Data System (ADS)

    Li, Guangxue; Qiao, Lulu; Dong, Ping; Ma, Yanyan; Xu, Jishang; Liu, Shidong; Liu, Yong; Li, Jianchao; Li, Pin; Ding, Dong; Wang, Nan; Olusegun A, Dada; Liu, Ling

    2016-08-01

    Based on monthly averaged current, temperature, and salinity, we analyzed the changes of suspended sediment concentration (SSC) and the relationship with the warm current, coastal current, and cold water mass (CWM) in the East China Seas (ECSs). The result shows that the coastal current and surface diluted water are the route for transporting suspended sediment. The Kuroshio and its derived warm current branches play the important role of the continental shelf circulation system and control the diffusion of suspended sediment. High SSC has been mainly concentrated in coastal current and CWM. Two sedimentary dynamic patterns have been identified. The winter-half-year pattern lasts almost 7 months. The coastal currents off the Shandong Peninsula, northern Jiangsu, Zhejiang-Fujian coast are the main routes for diffusion and deposition of the suspended sediment from the Yellow River and Changjiang River. The summer-half-year pattern is characterized by the well-developed CWM. All CWMs have a unique function to trap suspended sediment under the thermocline due to weakening tidal current and residual current there. These CWMs in the Yellow Sea (YS) and north ECS are connected together. The layer above the thermocline is characterized by diluted water with low salinity, high temperature. Suspended sediment can be transported into the Okinawa Trough and the South Korea coast during this period. A strong eddy always occur nearby the Kuroshio bend at northeast Taiwan, which has promoted the exchange between the ECS shelf and Okinawa Trough, and the development of the shelf edge current and Taiwan warm current (TWC).

  10. Paraliobacillus sediminis sp. nov., isolated from sediment in East China Sea.

    PubMed

    Cao, Wen-Rui; Guo, Ling-Yun; Du, Zong-Jun; Das, Anindita; Saren, Gaowa; Jiang, Ming-Yu; Dunlap, Christopher A; Rooney, Alejandro P; Yu, Xin-Ke; Li, Tie-Gang

    2016-12-30

    A Gram-strain-positive, facultatively anaerobic, motile, endospore-forming, slight halophile bacterium, designated strain 126C4T, was isolated from sediment of the East China Sea. The strain was catalase-positive and oxidase-negative. Optimal growth occurred at 28-30℃, pH 7.0-7.5 and in the presence of 3-5% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequence comparisons showed that strain 126C4T was a member of the genus Paraliobacillus, with 16S rRNA gene sequence similarity to the type strains of the two described species of the genus, Paraliobacillus quinghaiensis YIM-C158T (sequence similarity 96.2 %) and Paraliobacillus ryukyuensis O15-7T (sequence similarity 95.3 %). The DNA G+C content was 39.6 mol%. The strain contained MK-7 as the sole respiratory quinone; anteiso-C15:0, C16:0, iso-C15:0 and iso-C16:0 as the major cellular fatty acids; and its polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylethanolamine, three glycolipids and four unknown phospholipid. On the basis of its phylogenetic position, phenotypic traits and chemotaxonomic characteristics, it is supported that strain 126C4T represents a novel species of genus Paraliobacillus, for which the name Paraliobacillus sediminis sp. nov. is proposed. The type strain is 126C4T (= KCTC 33762T= MCCC 1H00136T).

  11. Phenotypic Characters and Molecular Epidemiology of Campylobacter Jejuni in East China.

    PubMed

    Zeng, Dexin; Zhang, Xiaoping; Xue, Feng; Wang, Yanhong; Jiang, Luyan; Jiang, Yuan

    2016-01-01

    In this study, we investigated the distribution, phenotypic and molecular typing characters of Campylobacter jejuni in domestic fowl, and livestock populations in East China, to provide some reference for researches on its molecular epidemiology. A total of 1250 samples were collected from different animal sources, and C. jejuni strains were then isolated and tested for antibiotic sensitivity. Antibiotics-resistance gene and pathogenic genes were detected by polymerase chain reaction. Phylogenic analysis on the C. jejuni strains was performed by multilocus sequence typing (MLST) method. The results showed that 108 out of the 1250 samples (mean 8.64%) were C. jejuni positive. These 108 C. jejuni strains were highly sensitive to antibiotics such as chloramphenicol, amoxicillin, amikacin, cefotaxime, and azithromycin, whereas they were highly resistant to antibiotics such as cefoperazone, cotrimoxazole, cefamandole, sulfamethoxazole, and cefradine. Pathogenicity related gene identification indicated that the mean carrying rate of adhesion related gene cadF and racR, flagellin gene flaA, toxin regulating gene cdtA, cdtB, cdtC, wlaN and virB11, heat shock proteins and transferring proteins related genes dnaJ and ceuE, CiaB and pldA were 92.45%, 38.69%, 73.58%, 71.70%, 52.83%, 96.23%, 12.26%, 1.89%, 0.94%, 65.09%, 39.62% and 9.43%, respectively. A total of 58.82% of these strains contained more than 6 pathogenicity-related genes. MLST typed 58 ST types from the 108 isolated C. jejuni strains, including 24 new types, and ST-21 was the major type, accounting for 39.3% of the total strains.

  12. Sources, behaviors and degradation of dissolved organic matter in the East China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Yan; Yang, Gui-Peng; Liu, Li; Zhang, Peng-Yan; Leng, Wei-Song

    2016-03-01

    Concentrations of dissolved organic carbon (DOC), dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON) and its major compound classes-total hydrolysable amino acids (THAA) were measured at 4 cross-shelf transects of the East China Sea in July 2011. Surface concentrations of DOC, DIN, DON and THAA at the nearshore stations were mostly in excess of those found at the offshore sites, indicating either substantial autochthonous production or allochthonous inputs from the Changjiang River. The vertical distributions of DOC, DON and THAA showed similar trends with higher values in the surface layer, whereas the elevated concentrations of DIN were observed in the bottom layer. Major constituents of THAA presented in the study area were glycine, serine, alanine, glutamic acid, aspartic acid and valine. The mole percentages of neutral amino acids increased from surface water to bottom water, whereas acidic and hydroxy amino acids decreased with the water depth. Concentrations of DOC and THAA were negatively correlated to the ΔDIN values (the difference between the real concentration and theoretical concentration), respectively, indicating the coupling relation between dissolved organic matter (DOM) remineralization and nutrient regeneration in the water column. The C/N ratios in the water column exhibited different characteristics with elevated values appearing in the surface and bottom layers. Box and whisker plots showed that both degradation index (DI) values and THAA yields displayed a decreasing trend from the surface layer to the bottom layer, implying increasing degradation with the water depth. Our data revealed that glycine and alanine increased in relative abundance with decreasing DI, while tyrosine, valine, phenylalanine and isoleucine increased with increasing DI.

  13. Trichoderma Biodiversity of Agricultural Fields in East China Reveals a Gradient Distribution of Species

    PubMed Central

    Chen, Jing; Mao, Li-Juan; Feng, Xiao-Xiao; Zhang, Chu-Long; Lin, Fu-Cheng

    2016-01-01

    We surveyed the Trichoderma (Hypocreales, Ascomycota) biodiversity in agricultural fields in four major agricultural provinces of East China. Trichoderma strains were identified based on molecular approaches and morphological characteristics. In three sampled seasons (spring, summer and autumn), 2078 strains were isolated and identified to 17 known species: T. harzianum (429 isolates), T. asperellum (425), T. hamatum (397), T. virens (340), T. koningiopsis (248), T. brevicompactum (73), T. atroviride (73), T. fertile (26), T. longibrachiatum (22), T. pleuroticola (16), T. erinaceum (16), T. oblongisporum (2), T. polysporum (2), T. spirale (2), T. capillare (2), T. velutinum (2), and T. saturnisporum (1). T. harzianum, T. asperellum, T. hamatum, and T. virens were identified as the dominant species with dominance (Y) values of 0.057, 0.052, 0.048, and 0.039, respectively. The species amount, isolate numbers and the dominant species of Trichoderma varied between provinces. Zhejiang Province has shown the highest diversity, which was reflected in the highest species amount (14) and the highest Shannon–Wiener diversity index of Trichoderma haplotypes (1.46). We observed that relative frequencies of T. hamatum and T. koningiopsis under rice soil were higher than those under wheat and maize soil, indicating the preference of Trichoderma to different crops. Remarkable seasonal variation was shown, with summer exhibiting the highest biodiversity of the studied seasons. These results show that Trichoderma biodiversity in agricultural fields varies by region, crop, and season. Zhejiang Province (the southernmost province in the investigated area) had more T. hamatum than Shandong Province (the northernmost province), not only in isolate amounts but also in haplotype amounts. Furthermore, at haplotype level, only T. hamatum showed a gradient distribution from south to north in correspondence analysis among the four dominant species. The above results would contribute to the

  14. Distribution of phthalate esters in agricultural soil with plastic film mulching in Shandong Peninsula, East China.

    PubMed

    Li, Kankan; Ma, Dong; Wu, Juan; Chai, Chao; Shi, Yanxi

    2016-12-01

    The content of phthalate esters (PAEs) was investigated in 36 vegetable fields with plastic film mulching in Shandong Peninsula, East China. Soils at depths of 0-10 cm, 10-20 cm, and 20-40 cm were collected, and 16 PAEs were analyzed by gas chromatography-mass spectrometry. PAEs were detected in all the analyzed samples. The total contents of the 16 PAEs (Σ16PAEs) ranged from 1.374 to 18.810 mg/kg, with an average of 6.470 mg/kg. Among the four areas of Shandong Peninsula, including Qingdao, Weihai, Weifang, and Yantai, the highest Σ16PAE in the soil was observed in Weifang district (9.786 mg/kg), which is famous for large-scale vegetable production. Despite the significant differences among the Σ16PAEs, the PAE compositions in soils with plastic film mulching in Shandong Peninsula were comparable. Diethyl phthalate (DEP), diisobutyl phthalate, and di(4-methyl-2-pentyl) phthalate were present in all the samples, whereas di-n-hexyl phthalate was detected only in Qingdao (∼1%) and dicyclohexyl phthalate was observed only in Weifang (5.7-8.2%) in low proportions. The ratios of dimethyl phthalate, DEP, and di-n-butyl phthalate, which exceeded allowable concentrations, were 63.9-100% at different soil depths, indicating high PAE pollution. The concentration of butyl benzyl phthalate detected only in Weifang exceeded the recommended allowable soil concentration. Overall, the high PAE content in the soil with plastic film mulching in Shandong Peninsula is an issue of concern because of the large amounts of plastic film used.

  15. Bioluminescence of Aequorea macrodactyla, a common jellyfish species in the East China Sea.

    PubMed

    Xia, Ning-Shao; Luo, Wen-Xin; Zhang, Jun; Xie, Xiao-Yan; Yang, Hai-Jie; Li, Shao-Wei; Chen, Ming; Ng, Mun-Hon

    2002-03-01

    Studies of the bioluminescent mechanisms of jellyfish have been mainly confined to one species, Aequorea victoria. We describe the luminescent system of another species, Aequorea macrodactyla, which is commonly found in the warmer waters on the coastal region of East China Sea. The luminescent system of this species consists of a green fluorescent protein (GFP) and one or more aequorins. The GFP gene is 1042 bp. It encompasses a coding sequence of 717 bp organized as 3 exons, and it is predicted to specify a 27-kDa peptide, which shares 80% amino acid sequence identity with the GFP of A. victoria. The entire coding sequence was cloned into the pTO-T7 expression vector and expressed in Escherichia coli. Compared with GFP of A. victoria, the purified expressed protein exhibited an excitation peak at a higher wavelength of 476 nm and an emission peak at a lower wavelength of 496 nm, with a higher quantum yield of 1.0. The other photoprotein, aequorin, is encoded in a single open reading frame of 585 bp specifying a 23-kDa apoprotein. The gene was cloned in to the same expression vector and expressed in E. coli. The activity of the photoprotein was reconstituted by incubating the expressed apoprotein with coelenterazine f. In the presence of Ca(2+) the reconstituted aequorin exhibits an emission peak at 470 nm. The kinetics of regeneration and the photoactivities of the reconstituted aequorins of the 2 species of jellyfish are similar. Nevertheless, Aequorea macrodactyla is expected to appear brighter and more "blue" than Aequorea victorea because of the differences in the photoactivity of their GFPs.

  16. On the recurrent Ulva prolifera blooms in the Yellow Sea and East China Sea

    NASA Astrophysics Data System (ADS)

    Hu, Chuanmin; Li, Daqiu; Chen, Changsheng; Ge, Jianzhong; Muller-Karger, Frank E.; Liu, Junpeng; Yu, Feng; He, Ming-Xia

    2010-05-01

    A massive bloom of the green macroalgae Ulva prolifera (previously known as Enteromorpha prolifera) occurred in June 2008 in the Yellow Sea (YS), resulting in perhaps the largest "green tide" event in history. Using a novel index (Floating Algae Index) and multiresolution remote sensing data from MODIS and Landsat, we show that U. prolifera patches appeared nearly every year between April and July 2000-2009 in the YS and/or East China Sea (ECS), which all originated from the nearshore Subei Bank. A finite volume numerical circulation model, driven by realistic forcing and boundary conditions, confirmed this finding. Analysis of meteorological/environmental data and information related to local aquaculture activities strongly supports the hypothesis that the recurrent U. prolifera in the YS and ECS resulted from aquaculture of the seaweed Porphyra yezoensis (or nori) conducted along the 200 km shoreline of the Subei Bank north of the Changjiang (Yangtze) River mouth. Given the continuous growth in aquaculture efforts in the region, similar macroalgae bloom events, such as the summer 2008 event, are likely to occur in the future, particularly between May and July. This was confirmed by the 2009 bloom event in the same regions and the same period. The profit of the local P. yezoensis aquaculture industry (˜16,000 Ha in 2007) is estimated as U.S. 53 million, yet the cost to manage the impact of the summer 2008 U. prolifera bloom exceeded U.S. 100 million. Therefore, better strategies are required to balance the economic benefit of seaweed aquaculture and the costs of environmental impacts.

  17. Satellite views of the Bohai Sea, Yellow Sea, and East China Sea

    NASA Astrophysics Data System (ADS)

    Shi, Wei; Wang, Menghua

    2012-10-01

    A comprehensive study of water properties for the Bohai Sea (BS), Yellow Sea (YS), and East China Sea (ECS) has been carried out with 8-year observations between 2002 and 2009 from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Aqua platform. Normalized water-leaving radiance spectra (nLw(λ)), chlorophyll-a concentration (Chl-a), diffuse attenuation coefficient at the wavelength of 490 nm (Kd(490)), total suspended matter (TSM), and sea surface temperature (SST) are used to quantify and characterize the physical, optical, biological, and biogeochemical properties and their seasonal and interannual variability in the BS, YS, and ECS regions. The BS, YS, and ECS feature highly turbid waters in the coastal regions and river estuaries with high Kd(490) over ∼3 m-1 and TSM concentrations reach over ∼50 g m-3. The optical, biological, and biogeochemical property features in these three seas show considerable seasonal variability. The dominant empirical orthogonal function (EOF) mode for Kd(490) and TSM variability in the BS, YS, and ECS regions is the seasonal mode, which accounts for about two-thirds of the total variance. Phytoplankton dynamics in open oceans of the BS, YS, and ECS is also found to play an important role in the Kd(490) variation, while its impact on the ocean turbidity (Kd(490)) is much less than that of seasonal winds and sea surface thermodynamics in coastal regions. The first EOF mode in SST for the regions is seasonal and accounts for nearly 90% of the total SST variance. The major mechanisms that drive ocean color property variations in the BS, YS, and ECS are the seasonal winds, ocean stratification, and sea surface thermodynamics due to the seasonal climate change, as well as coastal bathymetry, seasonal phytoplankton blooms, and river discharges.

  18. Impacts of South East Biomass Burning on local air quality in South China Sea

    NASA Astrophysics Data System (ADS)

    Wai-man Yeung, Irene; Fat Lam, Yun; Eniolu Morakinyo, Tobi

    2016-04-01

    Biomass burning is a significant source of carbon monoxide and particulate matter, which is not only contribute to the local air pollution, but also regional air pollution. This study investigated the impacts of biomass burning emissions from Southeast Asia (SEA) as well as its contribution to the local air pollution in East and South China Sea, including Hong Kong and Taiwan. Three years (2012 - 2014) of the Hybrid Single Particle Lagrangian-Integrated Trajectory (HYSPLIT) with particles dispersion analyses using NCEP (Final) Operational Global Analysis data (FNL) data (2012 - 2014) were analyzed to track down all possible long-range transport from SEA with a sinking motion that worsened the surface air quality (tropospheric downwash from the free troposphere). The major sources of SEA biomass burning emissions were first identified using high fire emissions from the Global Fire Emission Database (GFED), followed by the HYSPLIT backward trajectory dispersion modeling analysis. The analyses were compared with the local observation data from Tai Mo Shan (1,000 msl) and Tap Mun (60 msl) in Hong Kong, as well as the data from Lulin mountain (2,600 msl) in Taiwan, to assess the possible impacts of SEA biomass burning on local air quality. The correlation between long-range transport events from the particles dispersion results and locally observed air quality data indicated that the background concentrations of ozone, PM2.5 and PM10 at the surface stations were enhanced by 12 μg/m3, 4 μg/m3 and 7 μg/m3, respectively, while the long-range transport contributed to enhancements of 4 μg/m3, 4 μg/m3 and 8 μg/m3 for O3, PM2.5 and PM10, respectively at the lower free atmosphere.

  19. Appendix C: Summary of Major Metallogenic Belts in Northeast Asia (the Russian Far East, Yakutia, Siberia, Transbaikalia, Northern China, Mongolia, South Korea, and Japan)

    USGS Publications Warehouse

    Rodionov, Sergey M.; Obolenskiy, Alexander A.; Distanov, Elimir G.; Badarch, Gombosuren; Dejidmaa, Gunchin; Hwang, Duk-Hwan; Khanchuk, Alexander I.; Ogasawara, Masatsugu; Nokleberg, Warren J.; Parfenov, Leonid M.; Prokopiev, Andrei V.; Seminskiy, Zhan V.; Smelov, Alexander P.; Yan, Hongquan; Davydov, Yuriy V.V.; Fridovskiy, Valeriy Yu.; Gamyanin, Gennandiy N.; Gerel, Ochir; Kostin, Alexei V.; Letunov, Sergey A.; Li, Xujun; Nikitin, Valeriy M.; Ratkin, Vladimir V.; Shpikerman, Vladimir I.; Sudo, Sadahisa; Sotnikov, Vitaly I.; Spiridonov, Alexander V.; Stepanov, Vitaly A.; Sun, Fengyue; Sun, Jiapeng; Sun, Weizhi; Supletsov, Valeriy M.; Timofeev, Vladimir F.; Tyan, Oleg A.; Vetluzhskikh, Valeriy G.; Wakita, Koji; Yakovlev, Yakov V.; Zorina, Lydia M.

    2010-01-01

    tectonics of Northeast Asia that have been led by the U.S. Geological Survey (USGS). These studies have produced two broad types of publications (1) a series of regional geologic, mineral-deposit, and metallogenic-belt maps, with companion descriptions of the region, and (2) a suite of metallogenic and tectonic analyses of the same region. The study area consists of eastern Russia (most of eastern Siberia and the Russian Far East), Mongolia, northern China, South Korea, Japan, and adjacent offshore areas. The major cooperative agencies are the Russian Academy of Sciences; the Academy of Sciences of the Sakha Republic (Yakutia); VNIIOkeangeologia and Ministry of Natural Resources of the Russian Federation; the Mongolian Academy of Sciences; the Mongolian University of Science and Technology; the Mongolian National University; Jilin University, Changchun, People?s Republic of China, the China Geological Survey; the Korea Institute of Geosciences and Mineral Resources; the Geological Survey of Japan/AIST; the University of Texas, Arlington, and the U.S. Geological Survey (USGS). This study builds on and extends the data and interpretations from a previous project on the Major Mineral Deposits, Metallogenesis, and Tectonics of the Russian Far East, Alaska, and the Canadian Cordillera conducted by the USGS, the Russian Academy of Sciences, the Alaska Division of Geological and Geophysical Surveys, and the Geological Survey of Canada. The major products of this project were summarized by Naumova and others (2006) and are described in appendix A.

  20. Holocene East Asian summer monsoon records in northern China and their inconsistency with Chinese stalagmite δ18O records

    NASA Astrophysics Data System (ADS)

    Liu, Jianbao; Chen, Jianhui; Zhang, Xiaojian; Chen, Fahu

    2016-04-01

    Monsoon precipitation over China exhibits large spatial differences. It has been found that a significantly enhanced East Asian summer monsoon (EASM) is characterized by increased rainfall in northern China and by reduced rainfall in southern China, and this relationship occurs on different time scales during the Holocene. This study presents results from a diverse range of proxy paleoclimatic records from northern China where precipitation variability is traditionally considered as an EASM proxy. Our aim is to evaluate the evolution of the EASM during the Holocene and to compare it with all of the published stalagmite δ18O records from the Asian Monsoon region in order to explore the potential mechanism(s) controlling the Chinese stalagmite δ18O. We found that the intensity of the EASM during the Holocene recorded by the traditional EASM proxy of moisture (or precipitation) records from northern China are significantly different from the Chinese stalagmite δ18O records. The EASM maximum occurred during the mid-Holocene, challenging the prevailing view of an early Holocene EASM maximum mainly inferred from stalagmite δ18O records in eastern China. In addition, all of the well-dated Holocene stalagmite δ18O records, covering a broad geographical region, exhibit a remarkably similar trend of variation and are statistically well-correlated on different time scales, thus indicating a common signal. However, in contrast with the clear consistency in the δ18O values in all of the cave records, both instrumental and paleoclimatic records exhibit significant spatial variations in rainfall on decadal-to- centennial time scales over eastern China. In addition, both paleoclimatic records and modeling results suggest that Holocene East Asian summer monsoon precipitation reached a maximum at different periods in different regions of China. Thus the stalagmite δ18O records from the EASM region should not be regarded as a reliable indicator of the strength of the East

  1. [Spatial distribution and pollution assessment of heavy metals in the tidal reach and its adjacent sea estuary of Daliaohe area, China ].

    PubMed

    Zhang, Lei; Qin, Yan-wen; Ma, Ying-qun; Zhao, Yan-min; Shi, Yao

    2014-09-01

    The aim of this article was to explore the pollution level of heavy metals in the tidal reach and its adjacent sea estuary of Daliaohe area. The contents and spatial distribution of As, Cd, Cr, Cu, Ph and Zn in surface water, suspended solids and surface sediments were analyzed respectively. The integrated pollution index and geoaccumulation index were used to evaluate the contamination degree of heavy metals in surface water and surface sediments respectively. The results indicated that the contents of heavy metals in surface water was in the order of Pb < Cu < Cd < Cr < As < Zn. The heavy metal contents in surface water increased from river to sea. Compared with the contents of heavy metals in surface water of the typical domestic estuary in China, the overall contents of heavy metals in surface water were at a higher level. The contents of heavy metals in suspended solids was in the order of Cd < Cu < As < Cr

  2. Distribution and ecological risk assessment of polycyclic aromatic hydrocarbons in water, suspended particulate matter and sediment from Daliao River estuary and the adjacent area, China.

    PubMed

    Zheng, Binghui; Wang, Liping; Lei, Kun; Nan, Bingxu

    2016-04-01

    Polycyclic aromatic hydrocarbons (PAHs) contamination was investigated in concurrently sampled surface water, suspended particulate matter (SPM) and sediment of Daliao River estuary and the adjacent area, China. The total concentrations of PAHs ranged from 71.12 to 4255.43 ng/L in water, from 1969.95 to 11612.21 ng/L in SPM, and from 374.84 to 11588.85 ng/g dry weight (dw) in sediment. Although the 2-3 ring PAHs were main PAH congeners in water and SPM, the 4-6 ring PAHs were also detected and their distribution was site-specific, indicating a very recent PAHs input around the area since they were hydrophobic. The PAHs pollution was identified as mixed combustion and petroleum sources. Based on species sensitivity distribution (SSD), the ecological risk in SPM from 82% stations was found to be higher obviously than that in water. The risk in water was basically ranked as medium, while the risk in SPM was ranked as high. Analysis with sediment quality guidelines (SQGs) indicated that negative eco-risk occasionally occurred in about 50% stations, while negative eco-risk frequently occurred in about 3% stations only caused by Phenanthrene(Phe) and Dibenzo(a,h)anthracene(DBA). Here freshwater acute effects data together with saltwater data were used for SSD model. And this method could quickly give the rational risk information, and achieved our objective that compared the spatial difference of risk levels among three compartments. The results confirmed that the use of freshwater acute effects data from the ECOTOX database together with saltwater effects data is acceptable for risk assessment purposes in estuary.

  3. Characteristics and potential sources of atmospheric mercury at a subtropical near-coastal site in East China

    NASA Astrophysics Data System (ADS)

    Yu, Ben; Wang, Xun; Lin, Che-Jen; Fu, Xuewu; Zhang, Hui; Shang, Lihai; Feng, Xinbin

    2015-08-01

    To evaluate the impact of regional mercury (Hg) emissions and understand possible source regions of atmospheric Hg in Eastern China, 2 year observation for speciated atmospheric Hg was conducted at the Dameishan Atmospheric Observatory, a mountain site near the east coast of China. The observed concentration of total gaseous Hg (TGM) was 3.3 ± 1.4 ng m-3. During the sampling period, gaseous oxidized Hg and particulate bound Hg were 6.7 ± 4.3 pg m-3 and 180 ± 110 pg m-3 in winter and 5.9 ± 3.4 pg m-3 and 130 ± 100 pg m-3 in spring, respectively. The relatively high mean concentration of TGM was mainly caused by regional anthropogenic emissions and occasional long-range transport from domestic source regions. Seasonal variation in the TGM concentration was observed with lower values in the wet monsoon season (from May to September) and higher values in the dry monsoon season (from October to April). Backward trajectories and potential source contribution function analysis suggested that anthropogenic Hg emission from coal combustion in the Yangtze River Delta region was the most likely cause for the elevated TGM concentrations. Relatively clean air originating from the East China Sea was the most possible cause for the observed low TGM concentrations. Positive correlation between TGM concentration and air quality index suggests that emissions that influenced regional air quality contributed to the elevated TGM concentrations.

  4. Genetic diversity and population structure of Eleutheronema rhadinum in the East and South China Seas revealed in mitochondrial COI sequences

    NASA Astrophysics Data System (ADS)

    Sun, Xinxu; Xu, Dongdong; Lou, Bao; Zhang, Tao; Xin, Jian; Guo, Yaoshi; Ma, Shilei

    2013-11-01

    Eleutheronema rhadinum is a potential commercial fisheries species and is subject to intense exploitation in China. Knowledge on the population structure of E. rhadinum in Chinese coastal waters, which is important for sustainable exploitation and proper resource management, is lacking. In the present study, the genetic diversity and population structure of E. rhadinum were evaluated using a 564-base pair fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene. A total of 76 specimens were collected from three localities around the East (Qidong and Zhoushan) and South China Seas (Zhuhai). Among these individuals, nine polymorphic sites were detected and 11 distinct haplotypes were defined. High levels of haplotype diversity ( h =0.759±0.035) and low levels of nucleotide diversity ( π= 0.001 98±0.003 26) were observed in these populations. Hierarchical analysis of molecular variance (AMOVA) indicated that 96.72% of the genetic variation occurred within the populations, whereas 3.28% occurred among populations. No significant genealogical branches or clusters were recognized on the neighbor-joining tree. Intra-group variation among populations was significant ( φ st=0.032 85, P<0.01). These results suggest that E. rhadinum populations in the East and South China Seas have developed divergent genetic structures. Tests of neutral evolution and mismatch distribution suggest that E. rhadinum may have experienced a population expansion. The present study provides basic information for the conservation and sustainable exploitation of this species.

  5. Clay minerals as proxies of the late Quaternary East Asian monsoon evolution in the South China Sea revisited

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Li, X.; He, Z.; Colin, C.; Zhao, Y.

    2012-12-01

    Clay minerals have a significant role in sedimentation and paleoenvironment studies of the South China Sea. Many previous studies showed that the time series variation in late Quaternary clay mineral assemblages presents mostly glacial-interglacial cyclicity, and they were interpreted chemical weathering closely related to contemporaneous climatic changes of source areas. It is quite debatable whether clay minerals can directly indicate the East Asian monsoon evolution. To answer this question, we investigated sediment cores collected in various locations in the South China Sea during the MARCO POLO cruise in 2005, MD05-2904 (2066 m water depth, abbreviated w.d.) and MD05-2905 (1198 m w.d.) in the north, MD05-2901 (1254 m w.d.) and MD05-2899 (2393 m w.d.) in the west, and MD05-2895 (1982 m w.d.) in the south. Our results show that provenance supply and current transport directly control the clay mineralogical compositions in core and surface sediments, with various expression forms in different locations. In the north, the clay mineral assemblage indicates a relationship between surface current transport (for smectite) under the significant influence of the Kuroshio intrusion and deep water transport (for illite and chlorite). In the west, the East Asian monsoons forced surface currents and different clay-composition provenances affect the glacial-interglacial cyclicity of clay mineral variations. In the south, land-sea distribution variations controlled by the sea level change determine the sources of clay minerals. Our new studies suggest that the late Quaternary clay minerals in the South China Sea do not bear contemporaneous paleoclimatic features, and their implication for proxies of the East Asian monsoon evolution is realized through both the provenance supply and current transport processes.

  6. Increasing zooplankton size diversity enhances the strength of top-down control on phytoplankton in the East China Sea

    NASA Astrophysics Data System (ADS)

    Ye, L.; Chang, C.; García-Comas, C.; Gong, G.; Hsieh, C.

    2012-12-01

    Body size is one of the fundamental characteristics of organisms linking many ecosystem properties and functions. Recent studies suggest that environmental changes alter the size structure of pelagic food webs; however, ecosystem consequences of such changes remain unclear. Here we tested our main hypothesis that increasing zooplankton size diversity enhances top-down control on phytoplankton in the East China Sea (H1), as well as five conventional hypotheses explaining the top-down control: shallower zooplankton size spectrum enhances the strength of top-down control (H2); nutrient enrichment lessens the strength of top-down control (H3); increasing zooplankton taxonomic diversity enhances the strength of top-down control (H4); increasing fish predation is linked to decreasing the strength of top-down control of zooplankton on phytoplankton (H5); increasing temperature intensifies the strength of top-down control (H6). While the results of our univariate analyses support H1, H2, H3, and H4, more in depth analyses indicate that zooplankton size diversity is the most important factor in determining the strength of top-down control on phytoplankton in East China Sea. Our results suggest a new potential mechanism that increasing predator size diversity enhances the strength of top-down control on prey through diet niche partitioning. This mechanism can be explained by the concept of optimal predator-prey body-mass ratio concept. Suppose each size group of zooplankton predators has its own optimal phytoplankton prey size, increasing size diversity of zooplankton would promote diet niche partitioning of predators and thus elevates the top-down control.Fig. 1 Scatter plots the relationship between zooplankton/phytoplankton biomass ratio versus (A) zooplankton size diversity, (B) slope of zooplankton size spectrum, (C) Zoolankton Shannon diversity, (D) NO3, (E) PO4, (F) SiO3, (G) water temperature, and (H) fish larvae density in the East China Sea. Table 1. Results of the

  7. Characteristics of Flow Field in Relation to transportation of Eggs and Larvae of Pelagic Fish in the East China Sea

    NASA Astrophysics Data System (ADS)

    Morinaga, K.

    2003-12-01

    Jack mackerel (Trachurus japonicus), one of the most familiar pelagic fishes in the East China Sea was been spawned between winter and spring, estimating from temporal and spatial distributions of fishing grounds near the Kyushu coast. Recently, from result of distributions of larvae collected during February to March, it was reported that main spawning grounds had been formed in the southern part of the East China Sea. These eggs and larvae are transported from spawning grounds by the Kuroshio, and a part of them branches northward at northwest of the Amami Oshima Island. This portion is considered to be distributed to the Sea of Japan by the origin of the Tsushima warm current. However, it is difficult to estimate the amount of eggs and larvae, since there is little information about the branched flow from northern edge of the Kuroshio to the Tsushima warm current during winter season. In this paper, in order to make it clear that how eggs and larvae are transported to the Pacific Ocean or the Sea of Japan from the southern East China Sea, the flow pattern in the East China Sea is to be described. Especially a flow that branches from the Kuroshio at northwest of the Amami Oshima Island is described in detail. Using many infrared imagery obtained by NOAA satellite, we detected both the frontal waves generated at the northern edge of the Kuroshio and the path of warm water branched from the frontal waves. These results revealed important information to measure the volume transport of the Tsushima warm current efficiently. Frontal waves are to be broken on the northern edge of the Kuroshio and became the origins of the Tsushima warm current. We carried out ADCP measurement in and around a breaking frontal wave, by using the quadrireciprocal method which requires four round trip surveys along a transect during a diurnal tidal period of 24 hours and 50 minutes in order to remove a tidal current. We were able to acquire a detailed information about a fine structure of

  8. [Variations of zooplankton's community structure in reclaimed waters of Nanhui east tidal flat of Shanghai, East China].

    PubMed

    Li, Qiang; Ma, Chang-An; Lü, Wei-Wei; Tian, Wei; Yu, Ji; Zhao, Yun-Long

    2012-08-01

    From October 2010 to July 2011, an investigation was conducted on the zooplankton communities in reclaimed and natural waters in Nanhui east tidal flat to study the seasonal variations of the zooplankton's species composition, abundance, biomass, dominant species, and biodiversity, aimed to explore the differences in the zooplankton's community structure within and outside the reclaimed waters and the relationships of the community structure with several indispensable environmental factors such as water salinity, water temperature, and human activities. A total of 30 zooplankton species were identified, among which, 24 species were in reclaimed waters and dominated by rotifers, and 14 species were in natural waters and dominated by copepods. The average abundance of the zooplankton was obviously higher in reclaimed waters than in natural waters, but the average biomass was in adverse. The dominant species in reclaimed waters were freshwater species, such as Brachionus angularis, B. calyciflorus, and Mesocyclops leuckarti, while those in natural waters were brackish species, such as Sinocalanus sinensis, Schmackeria poplesia, and Tortanus vermiculus. Both in reclaimed and in natural waters, the dominant species had seasonal alternation. The Shannon index (H) and Pielou evenness index (J) of the zooplankton communities were higher in natural waters, but the Margalef species richness (d) and simplicity index (C) were higher in reclaimed waters. Cluster analysis and MDS evaluation indicated that there was an obvious difference in the community structure of zooplankton between reclaimed and natural waters. Reclamation could be the primary cause for the variations of the zooplankton's community structure in reclaimed waters, and environmental factors such as water salinity and tidal power also contributed to the variations.

  9. Sedimentary phosphorus species and sedimentation flux in the East China Sea

    NASA Astrophysics Data System (ADS)

    Fang, Tien-Hsi; Chen, Jui-Lin; Huh, Chih-An

    2007-06-01

    Core sediment samples were collected from the middle shelf of the East China Sea (ECS) to study the phosphorus forms, P accumulation rate (PAR), P burial efficiency and the burial flux in the ECS. The sediment samples were sequentially extracted and directly extracted to analyze different forms of sedimentary P: lossely sorbed P and iron-bound P (P CDB); inorganic P associated with francolite (carbonate fluorapatite, CFA), biogenic hydroxyapatite, smecite, and CaCO 3 (P CFA); detrital P (P Detrital); organic P (P Organic); and total P. In addition, the Fe contents in the citrate-dithionite-bicarbonate (CDB) extracted solution were also measured. The total concentrations of P in the surface sediments in the study area ranged from 13.5 to 22.3 μmol g -1. Inorganic P was the major form and accounted for 72-93% of the total P pool. The average percentage of each fraction of P followed the sequence: P Detrital (70%)>P Organic (15.5%)>P CDB (8.4%)>P CFA (5.8%). The distribution pattern of total P in the surface sediment was similar to that of P Detrital and P Organic, but different from that of P CDB and P CFA. The profile variation of P Organic was the most significant among the phosphorus forms at the study stations. The concentrations of P CDB and P CFA showed minor variation with depth. These results may suggest that transformations of P Organic, P CFA and P CDB occurred at the study stations during sedimentary P burial. Based on the concentrations of total P, P CDB and Fe CDB obtained in the present study and the mass accumulation rate (MAR) reported in the literature, the values of the PAR, the P diffusion flux ( JPFe) supplied by reducible iron hydroxides and the P burial efficiency were calculated. The calculated results for PAR and JPFe in the study area ranged from 1.02 to 24.23 μmol cm -2 yr -1 and from 0.1 to 2.11 μmol cm -2 yr -1, respectively. The phosphorus burial efficiency (PBE) was approximately 90%. The ECS is a phosphorus sink, and the average

  10. Importance of planktonic community respiration on the carbon balance of the East China Sea in summer

    NASA Astrophysics Data System (ADS)

    Chen, Chung-Chi; Chiang, Kuo-Ping; Gong, Gwo-Ching; Shiah, Fuh-Kwo; Tseng, Chun-Mao; Liu, Kon-Kee

    2006-12-01

    The East China Sea (ECS) is one of the largest continental shelves in the world; however, the role that biota plays in the carbon fluxes of this shelf ecosystem is still obscure. To evaluate the organic carbon balance and the roles played by planktonic communities in organic carbon consumption, two cruises with stations covering almost the entire shelf were conducted during the high productivity and high river flow season of the ECS in June (the early summer) and August (the middle summer) 2003. Results showed that biological activity was significantly higher in the early summer. To flourish in the early summer, plankton need a significant fluvial input of dissolved inorganic nutrients and organic matter from the Chinese coast, especially from the Changjiang (aka Yangtze River), might be one of the main driving forces. Further analysis showed that most planktonic community respiration (PCR) could be attributed to phytoplankton and bacterioplankton, which accounted for over 96% of the total planktonic biomass (in carbon units) in summer. This might partially explain why mean PCR was higher in June (˜114 mg C m-3 d-1), with higher phytoplankton biomass, than in August (˜40 mg m-3 d-1). The ratio of integrated primary production to PCR (i.e., the P/R ratio) was, however, less than 1, with a mean ± SD value of 0.35 ± 0.41 for all the pooled data. This indicates a significant amount of organic carbon has been regenerated through planktonic activity in the water column. The sea-air difference in fCO2, however, changed from a mean value of -64.5 ± 61.3 ppm in June to 10.0 ± 37.5 ppm in August. To explain the contradictory results between PCR and fCO2, we suggest that the dissolved inorganic carbon regenerated through planktonic respiration could be stored in the subsurface layer and may affect the fCO2 in the surface water, which is what controls the shelf sea either as an atmospheric CO2 sink or as a source, depending on the prevailing physical forces. These

  11. Geochemical forms and seasonal variations of phosphorus in surface sediments of the East China Sea shelf

    NASA Astrophysics Data System (ADS)

    Zhou, Fengxia; Gao, Xuelu; Yuan, Huamao; Song, Jinming; Chen, Chen-Tung Arthur; Lui, Hon-Kit; Zhang, Yong

    2016-07-01

    Geochemical characteristics of phosphorus (P) in the surface sediments of the East China Sea shelf (ECSS) were studied in spring and autumn, 2014. Distributions, seasonal variations, transformations and their influencing factors were discussed. Besides, burial fluxes of P in different seasons were also calculated. Five operationally defined forms of P, namely exchangeable or loosely sorbed P (Ads-P), iron-bound P (Fe-P), authigenic P (Au-P), detrital apatite plus other inorganic P (De-P) and organic P (OP), were obtained using a sequential extraction procedure. Generally, the concentrations of Ads-P, Fe-P, Au-P and OP decreased seaward and the concentrations of De-P increased seaward in both seasons. In spring, the average concentrations of Ads-P, Fe-P, Au-P, De-P and OP were 13.8 ± 5.0, 21.9 ± 7.6, 148.5 ± 44.5, 153.1 ± 55.8 and 91.7 ± 21.5 μg g- 1, respectively. The corresponding concentrations in autumn were 11.4 ± 4.3, 20.0 ± 10.9, 170.4 ± 53.6, 225.6 ± 101.7 and 77.1 ± 33.9 μg g- 1, respectively. The average percentages of P fractions in total P (TP) in spring and autumn were both in the order: De-P > Au-P > OP > Fe-P > Ads-P. The average concentrations of Bio-available P (Bio-P) were 127.4 ± 31.4 μg g- 1 in spring and 108.5 ± 47.2 μg g- 1 in autumn, accounting for 29.8% ± 7.3% and 21.5% ± 8.2% of corresponding TP, respectively. Seasonal variations of the primary production, hydrodynamic conditions, hypoxia and other environmental conditions were responsible for the seasonal variations of different phosphorus forms. The calculation of burial fluxes reflected that, in most parts of the studied area, TP had relative high burial fluxes in autumn, while Bio-P had relatively high burial fluxes in spring. The burial fluxes of other phosphorus forms also showed different seasonal variations in different parts of the studied area.

  12. Exposure to pyrethroid pesticides and the risk of childhood brain tumors in East China.

    PubMed

    Chen, Sheng; Gu, Shuo; Wang, Yue; Yao, Yongliang; Wang, Guoquan; Jin, Yue; Wu, Yeming

    2016-11-01

    Pesticide exposure is hypothesized as one of the risk factors for the development of childhood brain tumors (CBT). This hospital-based case-control study evaluated the association of pyrethroid pesticide exposure with the risk for CBT in a children population in East China. In total, 161 CBT cases and 170 controls were recruited from 2 children's medical centers in Shanghai (Xinhua Hospital and Shanghai Children's Medical Center) between September 2012 and June 2015. The cases and controls were matched for age, sex, and province of residence. Pyrethroid pesticide exposure was evaluated by urinalysis of 3 nonspecific metabolites of pyrethroids (cis-DCCA, trans-DCCA, and 3-PBA) using gas chromatography-mass spectrometry (GC-MS) detection and by administering a questionnaire. Unconditional logistic regression showed that trans-DCCA, 3-PBA, and total metabolites (sum of the 3 metabolites) were positively associated with the increased risk of CBT. Children in the highest quartile had a nearly 3-fold increased risk of CBT compared with those in the lowest quartile after adjusting for confounding factors (trans-DCCA, odds ratio (OR) = 2.58, 95% confidence interval (CI), 1.38-4.80, p = 0.003; 3-PBA, OR = 3.26, 95% CI, 1.73-6.14, p < 0.0001; total metabolites, OR = 3.60, 95% CI, 1.87-6.93, p < 0.0001). We also found that exposure to both mosquitocide and cockroach killer was related to the increased risk of CBT (mosquitocide, OR = 1.68, 95% CI, 1.06-2.67, p = 0.027; cockroach killer, OR = 1.83, 95% CI, 1.13-2.95, p = 0.013). These findings indicate that exposure to pyrethroid pesticides might be associated with increased risk of CBT. Prospective cohort studies with larger sample sizes are required to confirm this conclusion.

  13. Detection and temporal variation of (60)Co in the digestive glands of the common octopus, Octopus vulgaris, in the East China Sea.

    PubMed

    Morita, Takami; Otosaka, Shigeyoshi; Fujimoto, Ken; Nishiuchi, Kou; Kimoto, Katsunori; Yamada, Haruya; Kasai, Hiromi; Minakawa, Masayuki; Yoshida, Katsuhiko

    2010-08-01

    (60)Co were detected in common octopus specimens collected in the East China Sea in 1996-2005. The source of (60)Co has remained unclear yet. Stable isotope analyses showed that there was no difference in stable Co concentrations between octopus samples with (60)Co and without (60)Co. This result showed that the stable Co in the digestive gland of octopus potentially did not include a trace amount of (60)Co and the source of (60)Co existed independently. Furthermore, investigations of octopus in other area and other species indicated that the origin of the source of (60)Co occurred locally in the restricted area in the East China Sea and not in the coastal area of Japan. Concentrations of (60)Co have annually decreased with shorter half-life than the physical half-life. This decrease tendency suggests that the sources of (60)Co were identical and were temporary dumped into the East China Sea as a solid waste.

  14. Driving forces in energy-related CO2 emissions in south and east coastal China: commonality and variations

    NASA Astrophysics Data System (ADS)

    Gao, C.; Liu, Y.; Jin, J.; Wei, T.

    2015-12-01

    East and south coastal China contributes to respectively about 30% and 8% of CO2 emissions in China and the world, and therefore play a critical role in achieving the national goal of emission reduction to mitigate the global warming. It also serves as a benchmark for the less developed regions of China, in terms of achieving the developed world's human development standard under lower per capita emissions. We analyze the driving forces of emissions in this region and their provincial characteristics by applying the Logarithmic Mean Divisia Index method. Our findings show that emissions have been doubled during the period from 2000 to 2012, along with three and two folds increase in economy and energy consumption, respectively. This suggests a persistent lock between economic growth and emissions, even in this socioeconomically advanced region in China. Provincial difference in annual emission growth reveals three distinguished low-carbon developmental stages, owning mainly to the effectiveness of energy efficiency in reducing emission growth. This may explain why previous climate policies have aimed to reduce carbon intensity. These results indicate that targeted measures on enhancing energy efficiency in the short term and de-carbonization of both the economic and energy structure in the long term can lower the emission growth more effectively and efficiently. They also suggest that factor-driven emission reduction strategies and policies are needed in the geographically and socioeconomically similar regions.

  15. The effect of grazing and viral lysis on the diel variations of Synechococcus spp. abundance in the East China Sea

    NASA Astrophysics Data System (ADS)

    Tsai, An Yi; Gong, Gwo-Ching; Hu, Shu Ling; Chao, Chien Fu

    2015-09-01

    Diel variations in the nanoflagellate grazing and viral-mediated mortality of Synechococcus spp. were simultaneously estimated using a dilution and size-fractionation approach in the inner (I-1 and I-2) and outer regions (O-1, O2 and O-3) of the Changjiang River plume in the East China Sea during summer 2014. Synechococcus spp. abundance generally tended to increase during the dark period, followed by a plateau until midnight at all sampling stations. Overall, gross growth rate of Synechococcus spp. ranged from 0.069 h-1 to 0.122 h-1 during the growth phase. Microzooplankton, nanoflagellate grazing, and viral lysis had no effect on the Synechococcus spp. abundance during this phase. Moreover, nanoflagellate grazing was the largest cause of Synechococcus spp. mortality during the loss phase at nighttime. Compared to the predators, viruses exerted only a minor impact on mortality at St. I-1, where we detected some of the effect that this community had on Synechococcus spp.. Little is known about the impact of nanoflagellates and viruses on the short-term dynamics of Synechococcus spp. in the East China Sea. Therefore, this study's characterization of the relative importance of nanoflagellates and viruses may help provide a better understanding of trophic structures and the energy flow within the microbial loop.

  16. Analysis of weather regime dependent wind biases over the east coast of China using 3 year WRF simulations

    NASA Astrophysics Data System (ADS)

    Lin, N.; Zhao, Y.; Xue, W.; Lin, Y.

    2015-12-01

    Reliable wind power resource estimates required by wind energy industry can be achieved by long term wind tower measurements or mesoscale model simulations. However, how to quantify and investigate the characteristics of wind bias of mesoscale modeling remain a challenge.Three-year simulations using WRF over the east coast of China have been conducted. A K-means cluster analysis is used to categorize the dominant weather regimes over this area.A systematic overestimate of wind speed over the coastal area is found during the daytime within the sea breeze dominant regime. Further analysis indicates that the positive bias is closely related to the strength of mixing within the boundary layer and land surface temperature bias. A typical sea breeze case is analyzed in terms of its evolution with a focus on the vertical and inland intrusion extent. A good simulation of local land sea breeze is critical for offshore and onshore wind farm design and operations over the east coast of China.

  17. Variations of surface ozone at Ieodo Ocean Research Station in the East China Sea and influence of Asian outflows

    NASA Astrophysics Data System (ADS)

    Han, J.; Shin, B.; Lee, M.; Hwang, G.; Kim, J.; Shim, J.; Lee, G.; Shim, C.

    2015-06-01

    Ieodo Ocean Research Station (IORS), a research tower (~ 40 m a.s.l.) for atmospheric and oceanographic observations, is located in the East China Sea (32.07° N, 125.10° E). The IORS is almost equidistant from South Korea, China, and Japan and, therefore, it is an ideal place to observe Asian outflows without local emission effects. The average ozone concentrations were 51.8 ± 15.9 ppbv during June 2003-December 2010. The seasonal variation of ozone was distinct, with a summer minimum (37.8 ppbv) and a spring maximum (61.1 ppbv), and was largely affected by seasonal wind pattern over East Asia. The fractional contribution of ozone at IORS could be attributed to six well distinguished air masses that were classified by the cluster analysis of backward trajectories. Marine air from the Pacific Ocean represents a relatively clean background air with a lowest ozone level of 32.2 ppbv in summer. In spring and winter the influence of Chinese outflows was dominant with higher ozone concentrations of 61.6 and 49.3 ppbv, respectively. This study confirms that the influence of Chinese outflows was the main factor determining O3 levels at IORS, of which extent was apt to be changed by meteorological state, particularly at a long-term scale.

  18. Variations of surface ozone at Ieodo Ocean Research Station in the East China Sea and the influence of Asian outflows

    NASA Astrophysics Data System (ADS)

    Han, J.; Shin, B.; Lee, M.; Hwang, G.; Kim, J.; Shim, J.; Lee, G.; Shim, C.

    2015-11-01

    Ieodo Ocean Research Station (IORS), a research tower (~ 40 m a.s.l.) for atmospheric and oceanographic observations, is located in the East China Sea (32.07° N, 125.10° E). The IORS is almost equidistant from South Korea, China, and Japan and, therefore, it is an ideal place to observe Asian outflows without local emission effects. The seasonal variation of ozone was distinct, with a minimum in August (37 ppbv) and two peaks in April and October (62 ppbv), and was largely affected by the seasonal wind pattern over east Asia. At IORS, six types of air masses were distinguished with different levels of O3 concentrations by the cluster analysis of backward trajectories. Marine air masses from the Pacific Ocean represent a relatively clean background air with a lowest ozone level of 32 ppbv, which was most frequently observed in summer (July-August). In spring (March-April) and winter (December-February), the influence of Chinese outflows was dominant with higher ozone concentrations of 62 and 49 ppbv, respectively. This study confirms that the influence of Chinese outflows was the main factor determining O3 levels at IORS and its extent was dependent on meteorological state, particularly at a long-term scale.

  19. Tracing floating green algae blooms in the Yellow Sea and the East China Sea using Lagrangian transport simulations

    NASA Astrophysics Data System (ADS)

    Park, Young-Gyu; Son, Young Baek; Choi, Byoung-Ju; Kim, Yong Hoon

    2014-05-01

    Lagrangian particle tracking experiments were conducted to understand the pathway of the floating green algae patches observed in the Yellow Sea (YS) and East China Sea (ECS) in summer 2011. The numerical simulation results indicated that dominant southerly winds during June and July 2011 were related to offshore movement of the floating green algae, especially their eastward extension in the YS/ECS. An infrequent and unusual event occurred in June 2011: a severe Tropical Strom MEARI, caused the green algae to detach from the coast and initiated movement to the east. After the typhoon event, sea surface temperature recovered rapidly enough to grow the floating green algae, and wind and local current controlled the movement of the massive floating algae patches (coastal accumulation or offshore advection in the area). Analysis of the floating green algae movement using satellite images during passage of Typhoon MAON in July 2011 revealed that the floating green algae patches were significantly controlled by both ocean currents and enhanced winds. These findings suggest that the floating green algae bloom off Qingdao, China and in the middle of the YS and ECS in the summer of 2011 occurred due to the combined effects of recent rapid expansion of seaweed aquaculture, strong winds, and the wind patterns in blooming regions. Our combined approach, using satellite data and numerical simulations, provides a robust estimate for tracing and monitoring changes in green algae blooms on a regional scale.

  20. Molecular identification of Anisakis and Hysterothylacium larvae in marine fishes from the East China Sea and the Pacific coast of central Japan.

    PubMed

    Kong, Qingming; Fan, Lanfen; Zhang, Junhe; Akao, Nobuaki; Dong, Kewei; Lou, Di; Ding, Jianzu; Tong, Qunbo; Zheng, Bin; Chen, Rui; Ohta, Nobuo; Lu, Shaohong

    2015-04-16

    Anisakiasis is a human disease caused by the accidental ingestion of larvae belonging to the family Anisakidae. Three fish species, the small yellow croaker Pseudosciaena polyactis, the mackerel Pneumatophorus japonicus and the hairtail Trichiurus haumela are important source for food products in the East China Sea. The prevalence and the identification of Anisakidae larvae in these fishes will benefit the prevention and control of anisakiasis. In this study, fish samples were obtained from fish markers in the East China Sea and the Pacific coast of central Japan during April 2011 and July 2013. For species identification, the PCR-based restriction fragment length polymorphism (PCR-RFLP) analysis of the entire ITS region (ITS1, 5.8 S and ITS2) of nuclear ribosomal DNA (rDNA) was performed. In total, 2004 larvae were collected from 80 hairtail fish, 20 small yellow croaker, and 27 mackerel from the East China Sea and the Pacific coast of central Japan. High prevalence of Anisakidae larvae infection (116/122, 95.1%) was detected in the East China Sea. Seven species were identified belonging to the genera Anisakis (Nematoda: Anisakidae) and Hysterothylacium (Nematoda: Anisakidae). Anisakis pegreffii was the predominant species accounting for 84.8% of all larvae examined in East China Sea, while all Anisakidae larvae isolated from Japan were identified as Anisakis simplex sensu stricto (s.s.). In the East China Sea, A. simplex s.s. and Anisakis typica were 0.6% (4/619) and 1.5% (9/619) of the identified nematodes, respectively. Interestingly, one larva was identified as a recombinant genotype of A. simplex s.s. and A. pegreffii. In addition, four species of the genus Hysterothylacium, namely, Hysterothylacium amoyense (31/619, 5.0%), Hysterothylacium aduncum (10/619, 1.6%), Hysterothylacium fabri (21/619, 3.4%) and Hysterothylacium spp. (18/619, 2.9%) were also identified in the present study. This is a comprehensive epidemiological dataset for the family Anisakidae in

  1. 21ST Century United States Military Strategy for East Asia: Countering an Emerging China

    DTIC Science & Technology

    2006-05-31

    with other nations.16 China opened its diplomatic and economic doors in the 1960s and 1970s. At first glance it might appear as a symbolic gesture to be...both the U.S. and China have avoided direct military engagement, tacitly acknowledging the potential consequences of open conflict on their...Dragon or Dinosaur ? Nuclear Weapons in a Modernizing China, ”Parameters 34 (Winter 2003-04): 101. 6 Alfred D. Wilhelm, Jr., The Chinese at the

  2. [Temporal and spatial distribution of particulate organic carbon in the Yellow Sea and East China Sea in spring].

    PubMed

    Cheng, Jun; Shi, Xiao-Yong; Zhang, Chuan-Song; Wang, Li-Sha; Huang, Shuang; Liu, Dong-Sheng

    2011-09-01

    Based on the data from cruises that carried out in the Yellow Sea and East China Sea from April to May, 2009, the temporal and spatial distributions of the particulate organic carbon (POC) were analyzed. And the sources of POC were further discussed according to the chlorophyll a (Chl-a) and C/N. The results showed that the concentration of POC in the Yellow Sea and East China Sea ranged from 24.33 microg/L to 2 817.29 microg/L in spring and the average content was 230.76 microg/L. In horizontal distribution, the highest POC content is in the coastal zones and it tends to decrease toward the far shore on the whole. The highest concentration of POC appears at the northern of Jiangsu Province coastal waters both in surface layer and bottom layer in particular, which is mainly affected by resuspension of sediments. And there is also a second highest concentration in the vicinity of the Yangtze River estuary, indicating the primary influence in the Yangtze River is by diluted water. The concentration of POC in shallow sea area is the highest and distributed uniformly and it is primarily from terrestrial inputs and resuspension. Moreover, the resuspension is relatively stronger than terrestrial inputs. However, the POC concentration in far coast deep water area is under 75 microg/L and it reduces gradually with the increase of water depth, which shows ocean water characteristics. And the POC is mainly from the ocean. The diurnal change of POC concentration in the middle of East Sea shows half-cycle variation, as a whole, the concentration value is high both in the afternoon and midnight, while it is relatively low at dusk, which is mainly under the influence of biological activity at the scene.

  3. Modern muddy deposit along the Zhejiang coast in the East China Sea: Response to large-scale human projects

    NASA Astrophysics Data System (ADS)

    Xu, Gang; Liu, Jian; Liu, Shengfa; Wang, Zhongbo; Hu, Gang; Kong, Xianghuai

    2016-11-01

    Grain size and clay minerals in the surface sediment off Zhejiang Province, China, of the East China Sea were analyzed to study changes in grain size, muddy deposit boundary, and major riverine and other derived matters transport paths in the Zhejiang coastal muddy deposit since the impoundment of the Three Gorges Dam and after other large-scale human projects. The results show that the sediment types are mainly silt and mud in the muddy deposit, divided based on the 10% isoline of the sand-sized component. The sources of sediment in the muddy deposit are mainly the Yangtze River and simultaneously supplies from the Qiantang Jiang, Ou Jiang, relict fine-grain matter, and hydrolyzed volcanic rocks around the Zhoushan Islands. The transport and dispersal of sediments in the study area are largely controlled by the Zhejiang-Fujian coastal current and the Taiwan Warm Current and appear seasonally. The contributions from the Ou Jiang, relict matter, local hydrolyzed matter, and the Qiantang Jiang are enlarged owing to the decline of Yangtze suspended matter and the constructions of major human projects in the Hangzhou Bay, respectively. In addition, the sediment grain size exhibits a fining trend because of the influence of the Three Gorges Dam. The boundary of the muddy deposit is relatively stable after the Three Gorges Dam impoundment north of the city of Zhoushan. In contrast, south of the city of Zhoushan the boundary of the muddy deposit lies toward the east because the sediment supply from the relict fine-grained matters resuspended by the Taiwan Warm Current east of the study area. The changes in the grain size and contributions from smaller rivers and other derived matter as well as the boundary of the muddy deposit there will probably become more pronounced in the future.

  4. The effect of Kuroshio Current on nitrate dynamics in the southern East China Sea revealed by nitrate isotopic composition

    NASA Astrophysics Data System (ADS)

    Wang, Wentao; Yu, Zhiming; Song, Xiuxian; Wu, Zaixing; Yuan, Yongquan; Zhou, Peng; Cao, Xihua

    2016-09-01

    In spring 2014 (May-June), in the southern East China Sea (ECS) and east of Taiwan, nutrient and isotope samples were collected and analyzed. Also, dissolved oxygen (DO), chlorophyll-a, and physical parameters were determined. The Kuroshio subsurface water intruded into the ECS and separated into two branches on the continental shelf: the nearshore Kuroshio branch current (NKBC) and the offshore Kuroshio branch current (OKBC). Nitrate concentration in the Kuroshio subsurface water slightly decreased east of Taiwan by assimilation and was supplied by upwelling currents northeast of Taiwan. The variations of DO, nitrate, and nitrogen isotopes in the bottom water showed that continuous nitrification occurred in the NKBC after intrusion into the ECS. This process might contribute to the hypoxia zone near the coast of Zhejiang Province, China. Our results also indicated that internal nitrogen cycles appeared in NKBC since the isotope fractionation ratio of oxygen and nitrogen (18ɛ:15ɛ) in NO3- was 1.40. The NO3- flux and budget were calculated in the NKBC via numerical simulations. It demonstrated that at least ˜0.52 kmol NO3-·s-1 was produced by nitrification from DH9 to DH5 transect, and ˜0.11 kmol NO3-·s-1 was consumed in the DH4 transect. Moreover, according to the Rayleigh model, primary production in most of southern ECS was supported by the intrusion of the Kuroshio subsurface water, causing 5‰ isotope fractionation. In some of nearshore stations which located in the northern investigated area, the assimilated nitrate was contributed from both the NKBC and coastal currents originated from the Changjiang diluted water.

  5. Lateral variation in oxygen fugacity and halogen contents in early Cretaceous magmas in Jiaodong area, East China: Implication for triggers of the destruction of the North China Craton

    NASA Astrophysics Data System (ADS)

    Huang, Xiao-Long; He, Peng-Li; Wang, Xue; Zhong, Jun-Wei; Xu, Yi-Gang

    2016-04-01

    Pacific subduction has been suggested as the trigger of the destruction of the North China Craton, but evidence for it remains ambiguous. To further investigate this issue, we studied Wulian pyroxene monzonite (123 ± 1 Ma) in the west and Rushan gabbro-diorite (115 ± 1 Ma) in the east of the Sulu orogen, East China. The rocks of both locations are characterized by low TiO2 but high SiO2 and K2O, fractionated REE patterns with notable negative Ta-Nb-Ti anomalies, and by high initial 87Sr/86Sr ratios and strongly negative εNd (t) and εHf (t) values. These geochemical and isotopic characteristics can be interpreted to be formed by partial melting of enriched lithosphere mantle refertilized by recycled crustal materials that were associated with the Sulu orogeny. Oxygen fugacities of the Rushan gabbro-diorites, estimated based on magnetite-ilmenite equilibration, are significantly higher than those of Wulian pyroxene monzonite. This lateral difference is mirrored by lower F and F/Cl but higher Cl in biotite in the Rushan gabbro-diorite compared to Wulian pyroxene monzonite. All these data suggest a spatially heterogeneous Cretaceous mantle source in terms of halogens and water contents beneath the Sulu orogen, which was most likely caused by the subduction processes of the Pacific plate. H2O-rich fluid in the mantle beneath the east of the Sulu orogen closer to the mantle wedge was prominently from early dehydration of subducted slab at shallow depth, while F-bearing fluid to further west was released by dehydrated deeper slab or stagnant oceanic slab within the mantle transition zone.

  6. Remote sensing observations and numerical studies of a super typhoon-induced suspended sediment concentration variation in the East China Sea

    NASA Astrophysics Data System (ADS)

    Li, Yangdong; Li, Xiaofeng

    2016-08-01

    By integrating remote sensing observations and a numerical modeling technique, we studied the influences of super Typhoon Saomai on the suspended sediment concentration (SSC) in the Yangtze River estuary and its adjacent coastal areas in the East China Sea. First, three consecutive Moderate Resolution Imaging Spectroradiometer (MODIS) images acquired during the post-typhoon stage were used to estimate the SSC. Then, we implemented a hydrodynamic model, including a sediment transport module, based on Delft3D to simulate the sediment erosion, re-suspension, transport and deposition processes in the study area during the passage of Typhoon Saomai. The model-simulated water level was validated against the in situ station data to show the feasibility of the model. The simulated SSC results agree reasonably well with the satellite observations. Time series of the simulation results showed that the model revealed the whole SSC variations during this extreme weather event and made up for the scarcity of in-situ and satellite observations. SSC significantly increased during the passage of the typhoon and decreased gradually during the post-typhoon stage. Modeled results also reveal that the spring-neap tidal effect significantly controlled the distribution and variation of SSC in the shallower coastal water (<20-30 m in depth) and the typhoon-induced re-suspension is evident in most of the study area, especially in the coastal waters near the Yangtze River estuary and Hangzhou Bay during the passage of the typhoon. Finally, based on the simulation results, we discuss the dynamic mechanisms including turbulent energy, bed shear stress and vertical mixing that caused the SSC variation.

  7. Spatial-temporal variations of dominant drought/flood modes and the associated atmospheric circulation and ocean events in rainy season over the east of China

    NASA Astrophysics Data System (ADS)

    Huang, Shaoni; Huang, Fei

    2012-06-01

    By using Season-reliant Empirical Orthogonal Function (S-EOF) analysis, three dominant modes of the spatial-temporal evolution of the drought/flood patterns in the rainy season over the east of China are revealed for the period of 1960-2004. The first two leading modes occur during the turnabout phase of El Niño-Southern Oscillation (ENSO) decaying year, but the drought/flood patterns in the rainy season over the east of China are different due to the role of the Indian Ocean (IO). The first leading mode appears closely correlated with the ENSO events. In the decaying year of El Niño, the associated western North Pacific (WNP) anticyclone located over the Philippine Sea persists from the previous winter to the next early summer, transports warm and moist air toward the southern Yangtze River in China, and leads to wet conditions over this entire region. Therefore, the precipitation anomaly in summer exhibits a `Southern Flood and Northern Drought' pattern over East China. On the other hand, the basin-wide Indian Ocean sea surface temperature anomaly (SSTA) plays a crucial role in prolonging the impact of ENSO on the second mode during the ENSO decaying summer. The Indian Ocean basin mode (IOBM) warming persists through summer and unleashes its influence, which forces a Matsuno-Gill pattern in the upper troposphere. Over the subtropical western North Pacific, an anomalous anticyclone forms in the lower troposphere. The southerlies on the northwest flank of this anticyclone increase the moisture transport onto central China, leading to abundant rainfall over the middle and lower reaches of the Yangtze River and Huaihe River valleys. The anomalous anticyclone causes dry conditions over South China and the South China Sea (SCS). The precipitation anomaly in summer exhibits a `Northern Flood and Southern Drought' pattern over East China. Therefore, besides the ENSO event the IOBM is an important factor to influence the drought/flood patterns in the rainy season over

  8. Enrichment of heavy metals in the inner shelf mud of the East China Sea and its indication to human activity

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Fan, Dejiang; Li, Weiran; Wang, Liang; Zhang, Xilin; Liu, Ming; Guo, Zhigang

    2014-11-01

    The Yangtze River Basin, which has a population of 0.4 billion and an economic output accounting for 50% of China's Gross Domestic Product (GDP), is one of the most developed regions in China. With dramatic developments in the economy, large quantities of pollutants have entered the Yangtze River and have eventually been discharged into the East China Sea (ECS), and then most of them were preserved in the inner shelf coastal mud areas of the ECS. The inner shelf costal mud areas of the ECS, with sedimentation rate ranging from 0.8 cm/a to 1.2 cm/a, are an ideal place to obtain the high-resolution heavy metal record. In this work, two sediment cores collected in the inner shelf of the coastal mud areas of the ECS in 2009 were used to reconstruct historical records of anthropogenic heavy metal input from the Yangtze River Basin. The temporal distribution of enrichment factors (EFs) is in good accordance with social development of Yangtze River Basin. Before the 1930s, the EFs of Pb and Zn are considered as the background level of study area, according to the agricultural country of China in that time. The much higher EFs of Pb and Zn from the 1930s to 1980s were associated with significant improvement of industry of the Yangtze River Basin. After 1983, the dramatical incensement of EFs of Pb and Zn responded to the remarkable economic development of the Yangtze River Basin. Of particular interest, the construction of the Three Gorges Dam (TGD) in 2003 possibly induced a significant increase in the heavy metal levels in the coastal ECS, and the ban on leaded gasoline in China induced a remarkable decrease in Pb levels. Although heavy metal levels have increased since the 1930s, the coastal mud area of the ECS remains under low ecological risk.

  9. Education Policy Borrowing in China: Has the West Wind Overpowered the East Wind?

    ERIC Educational Resources Information Center

    Tan, Charlene; Chua, Catherine S. K.

    2015-01-01

    Recent education reform in China reflects the global trend of education policy borrowing from Anglophone countries such as the USA. The reform in China essentially advocates shifting from knowledge reproduction and didacticism to knowledge construction by students through a learner-centredness approach. Aware of the trend of borrowing policy from…

  10. [Distribution, flux and biological consumption of carbon monoxide in the East China Sea and the South Yellow Sea in summer].

    PubMed

    Wang, Jing; Lu, Xiao-Lan; Yang, Gui-Peng; Xu, Guan-Qiu

    2014-11-01

    Carbon monoxide (CO) concentration distribution, sea-to-air flux and microbial consumption rate constant, along with atmospheric CO mixing ratio, were measured in the East China Sea and the South Yellow Sea in summer. Atmospheric CO mixing ratios varied from 68 x 10(-9) -448 x 10(-9), with an average of 117 x 10(-9) (SD = 68 x 10(-9), n = 36). Overall, the concentrations of atmospheric CO displayed a decreasing trend from the coastal stations to the offshore stations. The surface water CO concentrations in the investigated area ranged from 0.23-7.10 nmol x L(-1), with an average of 2.49 nmol x L(-1) (SD = 2.11, n = 36). The surface water CO concentrations were significantly affected by sunlight. Vertical profiles showed that CO concentrations rapidly declined with depth, with the maximum values appearing in the surface water. CO concentrations exhibited obvious diurnal variations in the study area, with the maximum values being 6-40 folds higher than the minimum values. Minimal concentrations of CO all occurred before dawn. However, the maximal concentrations of CO occurred at noon. Marked diurnal variation in the concentrations of CO in the water column indicated that CO was produced primarily by photochemistry. The surface CO concentrations were oversaturated relative to the atmospheric concentrations and the saturation factors ranged from 1.99-99.18, with an average of 29.36 (SD = 24.42, n = 29). The East China Sea and the South Yellow Sea was a net source of atmospheric CO. The sea-to-air fluxes of CO in the East China Sea and the South Yellow Sea ranged 0.37-44.84 μmol x (m2 x d)(-1), with an average of 12.73 μmol x (m2 x d)(-1) (SD = 11.40, n = 29). In the incubation experiments, CO concentrations decreased exponentially with incubation time and the processes conformed to the first order reaction characteristics. The microbial CO consumption rate constants (K(co)) in the surface water ranged from 0.12 to 1.45 h(-1), with an average of 0.47 h(-1) (SD = 0

  11. Health Status, Cognitive and Motor Development of Young Children Adopted from China, East Asia, and Russia across the First 6 Months after Adoption

    ERIC Educational Resources Information Center

    Pomerleau, Andree; Malcuit, Gerard; Chicoine, Jean-Francois; Seguin, Renee; Belhumeur, Celine; Germain, Patricia; Amyot, Isabelle; Jeliu, Gloria

    2005-01-01

    We compared health status, anthropometric and psychological development of 123 children adopted before 18 months of age from China, East Asia (Vietnam, Taiwan, Thailand, South Korea, Cambodia), and Eastern Europe (mostly Russia). Data were collected close to the time of arrival, and 3 and 6 months later. Anthropometric measures included weight,…

  12. East Meet West? U.S. and China: Strategies for Global Leadership

    DTIC Science & Technology

    2013-03-01

    years of rich and ancient heritage, experience and cultural longevity is to be marveled at. The notion of “Zhongguo” or “Middle Kingdom” has stayed...founding hero; yet in the founding myth , he is reestablishing, not creating, an empire. China predated him; it strides into the historical... myths and pre-history inconsistencies also contribute to some of the territorial disputes in present-day China. “China’s history is accurately one of

  13. [Distributions of COD and petroleum hydrocarbons and their relationships with occurrence of red tide in East China Sea].

    PubMed

    Zhang, Chuansong; Wang, Xiulin; Shi, Xiaoyong; Han, Xiurong; Sun, Xia; Zhu, Chenjian; Lu, Rong

    2003-07-01

    Based on the data of COD and petroleum hydrocarbons collected in the cruise from April 25 to May 2, 2002 in intensive red tide occurrence areas in East China Sea, the distribution of COD, and petroleum hydrocarbons and the eutrophication index(EI) were analyzed. The results showed that the EI and COD value were both high in coastal water, and decreased gradually away from shore. After the preliminary study on the relationships between correlative factors and occurrence of red tide, it was found that high EI and COD were necessary. There would be great chances for the red tide to break out under conditions that the EI was between 2.5 and 15 and COD concentration was between 0.8 to 1.4 mg.L-1 in seawater, along with the favorable temperature and salinity.

  14. Internal wave effects on the ambient noise notch in the East China Sea: model/data comparison.

    PubMed

    Rouseff, Daniel; Tang, Dajun

    2006-09-01

    The vertical directivity pattern of the ambient noise field observed in shallow water is typically anisotropic with a trough in the horizontal. This trough, often called the ambient noise notch, develops because downward refraction steepens all rays emanating from near the sea surface. Variability in the environment has the potential to redistribute the noise into shallower angles and thereby fill the notch. In the present work, a model for the width and depth of the ambient noise notch is developed. Transport theory for acoustic propagation is combined with a shallow water internal wave model to predict the average output of a beamformer. Ambient noise data from the East China Sea are analyzed in the 1-to-5-kHz band. Good agreement between the model and the data for both the width and depth of the ambient noise notch is obtained at multiple frequencies, suggesting that internal wave effects are significant.

  15. Application of CEDA and ASPIC computer packages to the hairtail ( Trichiurus japonicus) fishery in the East China Sea

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Liu, Qun

    2013-01-01

    Surplus-production models are widely used in fish stock assessment and fisheries management due to their simplicity and lower data demands than age-structured models such as Virtual Population Analysis. The CEDA (catch-effort data analysis) and ASPIC (a surplus-production model incorporating covariates) computer packages are data-fitting or parameter estimation tools that have been developed to analyze catch-and-effort data using non-equilibrium surplus production models. We applied CEDA and ASPIC to the hairtail ( Trichiurus japonicus) fishery in the East China Sea. Both packages produced robust results and yielded similar estimates. In CEDA, the Schaefer surplus production model with log-normal error assumption produced results close to those of ASPIC. CEDA is sensitive to the choice of initial proportion, while ASPIC is not. However, CEDA produced higher R 2 values than ASPIC.

  16. The possible physical barrier and coastal dispersal strategy for Japanese grenadier anchovy, Coilia nasus in the East China Sea and Yellow Sea: evidence from AFLP markers.

    PubMed

    Han, Zhi-Qiang; Han, Gang; Wang, Zhi-Yong; Gao, Tian-Xiang

    2015-02-03

    In order to ascertain the taxonomic status of the Ariake Sea population of Japanese grenadier anchovy, Coilia nasus, and assess the contemporary possible genetic barrier between the west and east coastal waters of the East China Sea, we used amplified fragment length polymorphism (AFLP) markers to detect the genetic structure of C. nasus, in the East China Sea and Yellow Sea. Eighty-one individuals of C. nasus were collected from five locations and 12 individuals of Coilia mystus were sampled from the Yangtze River Estuary. A total of 371 loci were detected by five primer combinations, 310 of which were polymorphic (83.56%). Analysis of molecular variation (AMOVA) and pairwise fixation index (FST) revealed significant genetic differentiation among five samples, indicating limited gene flow among populations. The dendrogram for populations by neighbor-joining (NJ) cluster analysis provided evidence of a clear relationship between genetic and geographic patterns, supporting significant genetic differentiation between China coastal populations and Ariake Sea populations. Compared to the genetic divergence between C. nasus and C. mystus, the level of genetic differentiation between China and the Ariake Sea populations of C. nasus is obvious below the species level, indicating isolated populations of C. nasus in the Ariake Sea. Isolation by distance analysis revealed that direct ocean distance with deep-water at the continental slope and high salinity between west and east coastal waters of the East China Sea served as major physical barrier to C. nasus, supporting the coastal dispersal pattern in this estuarine species, and rejecting offshore dispersal strategy.

  17. Formation of the modern current system in the East China Sea since the early Holocene and its relationship with sea level and the monsoon system

    NASA Astrophysics Data System (ADS)

    Zheng, Xufeng; Li, Anchun; Wan, Shiming; Jiang, Fuqing; Yin, Xueming; Lu, Jian

    2015-07-01

    The Okinawa Trough is a natural laboratory for the study of air-sea interaction and paleoenvironmental change. It has been demonstrated that present offshore export of particles in the bottom nepheloid layer occur primarily with downwelling from the northeast winter monsoon, which is inhibited by a transverse circulation pattern in summer. This current system was very different during the Last Glacial Maximum owing to low sea level (-120 m) and exposure of a large shelf area. We collected sediment core Oki01 from the middle Okinawa Trough during 2012 using R/V Kexue No. 1 to elucidate the timing and cause of the current system transition in the East China Sea. Clay mineral, dry density, and elemental (Ti, Ca) composition of core Oki01 was analyzed. The results indicate that clay minerals derived mainly from the Huanghe (Yellow) and the Changjiang (Yangtze) Rivers during 16.0-11.6 ka, and the modern current system in the East China Sea formed beginning in the early Holocene. Therefore, mixing of East China Sea continental shelf, Changjiang River and partially Taiwan Island sediment are the major contributors. The decrease of log(Ti/Ca) and alternating provenance since the early Holocene indicate less sediment from the East China in summer because of resistance of the modern current system, i.e., a "water barrier" and upwelling. Conversely, sediment delivery persists in winter and log(Ti/Ca) indicates the winter monsoon signal since the early Holocene. Our evidence also suggests that sediment from Taiwan Island could be transported by the Kuroshio Current to the middle Okinawa Trough, where it mingles with winter monsoon-induced export of sediment from the Changjiang River and East China Sea continental shelf. Although the present research advances understanding of the evolutionary history of paleoenvironmental change in the Okinawa Trough, more sediment cores should be retrieved over wide areas to construct a larger scenario.

  18. The Possible Physical Barrier and Coastal Dispersal Strategy for Japanese Grenadier Anchovy, Coilia nasus in the East China Sea and Yellow Sea: Evidence from AFLP Markers

    PubMed Central

    Han, Zhi-Qiang; Han, Gang; Wang, Zhi-Yong; Gao, Tian-Xiang

    2015-01-01

    In order to ascertain the taxonomic status of the Ariake Sea population of Japanese grenadier anchovy, Coilia nasus, and assess the contemporary possible genetic barrier between the west and east coastal waters of the East China Sea, we used amplified fragment length polymorphism (AFLP) markers to detect the genetic structure of C. nasus, in the East China Sea and Yellow Sea. Eighty-one individuals of C. nasus were collected from five locations and 12 individuals of Coilia mystus were sampled from the Yangtze River Estuary. A total of 371 loci were detected by five primer combinations, 310 of which were polymorphic (83.56%). Analysis of molecular variation (AMOVA) and pairwise fixation index (FST) revealed significant genetic differentiation among five samples, indicating limited gene flow among populations. The dendrogram for populations by neighbor-joining (NJ) cluster analysis provided evidence of a clear relationship between genetic and geographic patterns, supporting significant genetic differentiation between China coastal populations and Ariake Sea populations. Compared to the genetic divergence between C. nasus and C. mystus, the level of genetic differentiation between China and the Ariake Sea populations of C. nasus is obvious below the species level, indicating isolated populations of C. nasus in the Ariake Sea. Isolation by distance analysis revealed that direct ocean distance with deep-water at the continental slope and high salinity between west and east coastal waters of the East China Sea served as major physical barrier to C. nasus, supporting the coastal dispersal pattern in this estuarine species, and rejecting offshore dispersal strategy. PMID:25654225

  19. Transport of East Asian dust storms to the marginal seas of China and the southern North Pacific in spring 2010

    NASA Astrophysics Data System (ADS)

    Tan, Sai-Chun; Li, Jiawei; Che, Huizheng; Chen, Bin; Wang, Hong

    2017-01-01

    The transport of a super-severe dust storm that occurred in East Asia from 19 to 22 March 2010 has been well documented by both model simulations and surface observations. We investigated the transport of this severe dust storm and several other spring 2010 dust storms using model simulations, backward trajectories, and measurements from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite. The model simulations indicated that the emission of dust in spring 2010 was about 35% higher than that in spring 2006 and was twice that of the 44-year average from 1960 to 2003. The dust emissions over two major source regions (western China and the Gobi Desert) in spring 2010 accounted for 86% of the total amount of dust. The simulated depositional flux over the two major source regions was c.2.7-9.0 times that over two marginal seas (the Yellow Sea and the East China Sea) and more than two magnitudes higher than that over the North Pacific Subtropical Gyre. The mean extinction coefficient observed by the CALIPSO satellite over the two source regions was c.1.3-3.7 times that over the two marginal seas and one magnitude higher than that over the North Pacific. This was consistent with the result from our model, suggesting that this model is able to capture the major features of dust storms. The vertical profiles recorded by the CALIPSO satellite indicated that the dust aerosol mainly floated from the ground to 13 km above ground level over the source regions and above the seas. A multiple dust layer appeared over the seas and the backward trajectories suggested that the dust aerosol in different layers may have been sourced from different regions.

  20. Alongshore and cross-shore circulations and their response to winter monsoon in the western East China Sea

    NASA Astrophysics Data System (ADS)

    Huang, Daji; Zeng, Dingyong; Ni, Xiaobo; Zhang, Tao; Xuan, Jiliang; Zhou, Feng; Li, Jia; He, Shuangyan

    2016-02-01

    An array of four bottom-mounted acoustic Doppler current profilers (ADCPs) were deployed during the winter of 2008 (28 December 2008 to 12 March 2009) along a cross-shelf section in the western East China Sea to investigate the winter circulation and its response to wind. During the observation period, the observed subtidal currents exhibit coherent spatial structure and temporal variation in terms of their mean (seasonal), trend (intra-seasonal), and synoptic variability. The subtidal currents are polarized roughly in the alongshore direction parallel to local isobaths, and the weak cross-shore current is closely linked to the alongshore component. The temporal variation of the currents follows the rhythm of wind stress, sea level, and sea level difference at the synoptic scale. The mean currents are basically composed of two anti-parallel currents in the alongshore direction: the East China Sea coastal current (ECSCC) flows southwestward along the inner shelf and the Taiwan warm current (TWC) flows in the opposite direction along the outer-shelf. The strongest current occurs over the mid-shelf as a coastal jet. The intra-seasonal currents exhibit an expansion and intensification of the ECSCC along with shrinking and weakening the alongshore component of the TWC. There is a significant increase in onshore current particularly over the mid-shelf. The fluctuations of synoptic currents show a significant positive correlation with wind stress, and the fluctuations are negatively correlated with sea level and sea level difference. The coherent spatial structure of the currents indicates that the depth-independent column motion is related to the sea level difference through a barotropic pressure gradient. The vertical shear of currents is related to the density-related baroclinic pressure gradient in the whole water column and to the friction within the surface and bottom boundary layers.

  1. Large particle flux of 239+240Pu on the continental margin of the East China Sea.

    PubMed

    Yamada, Masatoshi; Aono, Tatsuo

    2002-03-15

    Settling particles were collected from three locations in the East China Sea continental margin and analyzed for 239+240Pu. Two types of sediment traps were used, cylindrical traps and conical time-series traps. Surface sediment samples collected from five locations were also analyzed for 239+240Pu. Data from cylindrical traps showed there was a clear tendency for total mass fluxes to increase with depth at all three stations, and there was an especially large increase near the bottom. 239+240Pu concentrations in settling particles increased with depth from 1.76 mBq/g at 97-m depth to 3.0 mBq/g at 120-m depth and ranged from approximately 3 to 4 mBq/g at depths greater than 120 m. 239+240Pu concentrations collected in the near-bottom traps were approximately two times higher than those in the underlying surface sediments. Like total mass fluxes there was a clear tendency for 239+240Pu fluxes to increase with depth at every station, and the highest 239+240Pu fluxes were observed near the bottom. 239+240Pu concentrations in the time-series traps had little variation throughout the sampling period, though the total mass fluxes showed a large variation. A high variability of 239+240Pu fluxes occurred in very short period of time (1/2 day). The large fluxes of 239+240Pu might be attributed to episodic lateral transport of particles that flow down the continental slope with the nepheloid layer which was considered to be significant for 239+240Pu transport on the continental slope in the East China Sea.

  2. Human Remains from the Pleistocene-Holocene Transition of Southwest China Suggest a Complex Evolutionary History for East Asians

    PubMed Central

    Curnoe, Darren; Xueping, Ji; Herries, Andy I. R.; Kanning, Bai; Taçon, Paul S. C.; Zhende, Bao; Fink, David; Yunsheng, Zhu; Hellstrom, John; Yun, Luo; Cassis, Gerasimos; Bing, Su; Wroe, Stephen; Shi, Hong; Parr, William C. H.; Shengmin, Huang; Rogers, Natalie

    2012-01-01

    Background Later Pleistocene human evolution in East Asia remains poorly understood owing to a scarcity of well described, reliably classified and accurately dated fossils. Southwest China has been identified from genetic research as a hotspot of human diversity, containing ancient mtDNA and Y-DNA lineages, and has yielded a number of human remains thought to derive from Pleistocene deposits. We have prepared, reconstructed, described and dated a new partial skull from a consolidated sediment block collected in 1979 from the site of Longlin Cave (Guangxi Province). We also undertook new excavations at Maludong (Yunnan Province) to clarify the stratigraphy and dating of a large sample of mostly undescribed human remains from the site. Methodology/Principal Findings We undertook a detailed comparison of cranial, including a virtual endocast for the Maludong calotte, mandibular and dental remains from these two localities. Both samples probably derive from the same population, exhibiting an unusual mixture of modern human traits, characters probably plesiomorphic for later Homo, and some unusual features. We dated charcoal with AMS radiocarbon dating and speleothem with the Uranium-series technique and the results show both samples to be from the Pleistocene-Holocene transition: ∼14.3-11.5 ka. Conclusions/Significance Our analysis suggests two plausible explanations for the morphology sampled at Longlin Cave and Maludong. First, it may represent a late-surviving archaic population, perhaps paralleling the situation seen in North Africa as indicated by remains from Dar-es-Soltane and Temara, and maybe also in southern China at Zhirendong. Alternatively, East Asia may have been colonised during multiple waves during the Pleistocene, with the Longlin-Maludong morphology possibly reflecting deep population substructure in Africa prior to modern humans dispersing into Eurasia. PMID:22431968

  3. Seasonal circulation patterns of the Yellow and East China Seas derived from satellite-tracked drifter trajectories and hydrographic observations

    NASA Astrophysics Data System (ADS)

    Lie, Heung-Jae; Cho, Cheol-Ho

    2016-08-01

    We investigated seasonal circulation patterns of the Yellow and East China Seas (YECS), by reviewing previous works on the circulation and its dominant currents, and taking into account newly-compiled trajectories of satellite-tracked drifters collected between the 1980s and 2000s. The circulation patterns suggested before the 1990s can be categorized into two groups, depending on the identified origin of the Tsushima Warm Current in the Korea-Tsushima Straits: (i) branching from the Kuroshio southwest of Kyushu, or (ii) northeastward continuation of the Taiwan Strait throughflow. The branching of the Kuroshio southwest of Kyushu and northeast of Taiwan was clearly evidenced by current measurements and concurrent hydrographic surveys. However, there is still no clear evidence for the northeastward pathway of Taiwan Strait throughflow across the mid-shelf area of the East China Sea. Target-oriented surveys in the 1990s and 2000s employing advanced instruments, such as drifter tracking and acoustic Doppler current profiler measurements, now provide decisive proof of the clockwise rounding of the Cheju Warm Current around Jeju-do throughout the year, of the northeastward extension of Changjiang discharge in summer, and of the presence of the Yellow Sea Warm Current only in winter. Thus, both coastal currents in shallow water and secondary branch currents of the Kuroshio (such as the Yellow Sea Warm Current) are found to significantly change from winter to summer. To better present the basic pattern of YECS circulation and its seasonality, we have constructed seasonal circulations patterns, based on review results, on the newly-compiled drifter trajectories, and on hydrographic observations. Further investigations should be carried out in future, with support of comprehensive current measurements on shelf areas and through elaborate numerical modeling.

  4. The status of coastal oceanography in heavily impacted Yellow and East China Sea: Past trends, progress, and possible futures

    NASA Astrophysics Data System (ADS)

    Wang, Xiao Hua; Cho, Yang-Ki; Guo, Xinyu; Wu, Chau-Ron; Zhou, Junliang

    2015-09-01

    Coastal environments are a key location for transport, commercial, residential and defence infrastructure, and have provided conditions suitable for economic growth. They also fulfil important cultural, recreational and aesthetic needs; have intrinsic ecosystem service values; and provide essential biogeochemical functions such as primary productivity, nutrient cycling and water filtration. The rapid expansion in economic development and anticipated growth of the population in the coastal zones along the Yellow and East China Sea basin has placed this region under intense multiple stresses. Here we aim to: 1) synthesize the new knowledge/science in coastal oceanography since 2010 within the context of the scientific literature published in English; 2) report on a citation analysis that assesses whether new research topics have emerged and integrated over time, indicate the location of modelling and field-based studies; and 3) suggest where the new research should develop for heavily impacted estuaries and coastal seas of East Asia. The conclusions of the synthesis include: 1) China has emerged as a dominant force in the region in producing scientific literature in coastal oceanography, although the area of publications has shifted from its traditional fields such as physical oceanography; 2) there has been an increasing number of publications with cross-disciplinary themes between physical oceanography and other fields of the biological, chemical, and geological disciplines, but vigorous and systematic funding mechanisms are still lacking to ensure the viability of large scale multi-disciplinary teams and projects in order to support trans-disciplinary research and newly emerging fields; 3) coastal oceanography is responding to new challenges, with many papers studying the impacts of human activities on marine environment and ecology, but so far very few studying management and conservation strategies or offering policy solutions.

  5. Lagrangian Coherent Structures (LCS) and the dispersion of algal bloom and marine debris in the Yellow and East China Sea

    NASA Astrophysics Data System (ADS)

    Kim, Y. H.; Choi, B.; Son, Y. B.; Shim, W. J.; Hwang, J. H.; Park, Y.

    2012-12-01

    Series of satellite images show that the development and migration of green macroalgal bloom (known as Ulva prolifera) in the Yellow Sea (YS) and Eastern China Sea (ECS). This presentation will utilize the Lagrangian Coherent Structures (LCS) analysis to demonstrate the dispersion pattern of algal bloom patches. Analyzing LCS such as stable and unstable manifolds is one of emerging technologies for characterizing Lagrangian pathways in aquatic environments. This approach is based on the assumption that unstable manifolds such as ridges (i.e., high values) in the finite-time Lyapunov exponent (FTLE) fields coincide with material transport barriers. In this study, the FTLE fields were computed from gridded trajectories using flow fields provided by Regional Ocean Modeling System (ROMS) in the YS/ECS during summer 2011. The results show that there exist two strong transport barriers that lie along the east-west direction, at least, for the simulation period; one is located from the north of Changjiang River mouth to the middle of the Yellow Sea and the other one is stretched from the south of Shandong Peninsular toward east/southeast. This LCS analysis suggests that patches of green algae developed in the coastal region of Jiangsu Province during summer may migrate toward east into the middle of the YS or even toward Korean coast rather than extending along the Jiangsu coast, which is consistent with the observation results derived from the satellite ocean color data. In the very same manner, the utilization of LCS results to evaluate the distribution/transport pattern of marine debris in the YS/ECS will also be discussed during the presentation.

  6. Deviation from zeitgeist and motivation in the intergenerational transmission of individualistic and collectivistic values in East Germany and Shanghai, China.

    PubMed

    Schönpflug, Ute; Yan, Song

    2014-01-01

    Intergenerational intrafamilial transmission is a process by which acquired information passes from parent to offspring. The authors examined mechanisms of intergenerational transmission of individualistic and collectivistic values in 216 families with 1 adolescent child in 2 societies: East Germany and the Shanghai region in China. To clarify the impact of transmission from mother and father to son or daughter, this study analyzed the filter model by U. Schönpflug and L. Bilz (2009), including zeitgeist concerning value climate in the social context, each family member's deviation from the zeitgeist, and the familial motivation to transmit. The 2-dimensional structure (individualism and collectivism) of 10 values of the Portrait Value Questionnaire (Schwartz, Lehmann, & Rocca, 1999) differed somewhat in the 2 regions for adolescents and their fathers, but not for mothers. In East Germany, no significant direct transmission of value orientation was observed, whereas in Shanghai, fathers transmitted individualism and collectivism values. Family motivation impacted significantly on the child's value orientation in both regions. The zeitgeist measure had no significant influence on the transmission process whereas deviation from zeitgeist did. The gender of the child determined the level and transmission of collectivism, but not the transfer of individualism.

  7. Observations of flow variability through the Kerama Gap between the East China Sea and the Northwestern Pacific

    NASA Astrophysics Data System (ADS)

    Na, Hanna; Wimbush, Mark; Park, Jae-Hun; Nakamura, Hirohiko; Nishina, Ayako

    2014-02-01

    The Kerama Gap, near the middle of the Ryukyu Island chain, is the deepest channel with a sill depth of 1050 m connecting the East China Sea (ECS) to the Northwestern Pacific. We measured the flow through the Kerama Gap from June 2009 to June 2011. The 2 year mean transport, 2.0 ± 0.7 Sv, is into the ECS from the Northwestern Pacific; it contributes about 11% of the mean Kuroshio transport in the ECS at the PN line. Subtidal standard deviation of the transport through the Kerama Gap is 3.2 Sv, comparable to that of the PN-line Kuroshio transport (4.0 Sv), suggesting a significant effect of Kerama Gap transport on temporal variability of the Kuroshio transport in the ECS. Comparison with time series of satellite-measured sea surface height maps reveals that temporal variability of the Kerama Gap transport is related to the arrival of mesoscale eddies from the east: high (low) transport into the ECS is associated with the presence of a cyclonic (anticyclonic) eddy south of the Kerama Gap.

  8. A Trend Analysis: Rising Threshold for China to Use Force in Territorial Disputes in South and East China Seas

    DTIC Science & Technology

    2012-12-01

    and Political Implications.” Review of International Studies 31, no. 4 (October 2005): 715–733. Wang, Yong. “Evolving Asian Power Balances and...formulated at the beginning of the study . The first one posits that China has not changed its realist international attitude after the Cold War and its...strategies. However, regarding the regional militarization, it is difficult to determine the effects of military balance on the Chinese

  9. The Emergence of China in the Middle East (Strategic Forum, Number 271, December 2011)

    DTIC Science & Technology

    2011-12-01

    Chinese outbound tourism , but it is also indicative of Chinese travelers’ interests in the Middle East. Lo- cal tourism industries in countries such as...that used to take up to 4 months. For non–oil-producing countries whose economies rely heavily on the tourism industry , Chinese visitors repre- sent a...Moreover, the Iranian government even allowed Chinese fighter jets to travel through its airspace to join the drills. The Chinese arms industry has

  10. Distribution of short chain chlorinated paraffins in marine sediments of the East China Sea: influencing factors, transport and implications.

    PubMed

    Zeng, Lixi; Zhao, Zongshan; Li, Huijuan; Wang, Thanh; Liu, Qian; Xiao, Ke; Du, Yuguo; Wang, Yawei; Jiang, Guibin

    2012-09-18

    Short chain chlorinated paraffins (SCCPs) are high production volume chemicals in China and found to be widely present in the environment. In this study, fifty-one surface sediments and two sediment cores were collected from the East China Sea to study their occurrence, distribution patterns and potential transport in the marginal sea. SCCPs were found in all surface sediments and ranged from 5.8 to 64.8 ng/g (dry weight, d.w.) with an average value of 25.9 ng/g d.w. A general decreasing trend with distance from the coast was observed, but the highest value was found in a distal mud area far away from the land. The C10 homologue was the most predominant carbon chain group, followed by C11, C12, and C13 homologue groups. Significant linear relationship was found between total organic carbon (TOC) and total SCCP concentrations (R(2) = 0.51, p < 0.05). Spatial distributions and correlation analysis indicated that TOC, riverine input, ocean current, and atmospheric deposition played an important role in controlling SCCP accumulation in marine sediments. Vertical profiles of sediment cores showed that SCCP concentrations decreased from surface to the depth of 36 cm, and then slightly increased again with depth, which showed a significant positive correlation with TOC and chlorine contents (Cl%). The results suggest that SCCPs are being regionally or globally distributed by long-range atmospheric or ocean current transport.

  11. The intensification of the East Asian winter monsoon contributed to the disappearance of Cedrus (Pinaceae) in southwestern China

    NASA Astrophysics Data System (ADS)

    Su, Tao; Liu, Yu-Sheng (Christopher); Jacques, Frédéric M. B.; Huang, Yong-Jiang; Xing, Yao-Wu; Zhou, Zhe-Kun

    2013-09-01

    Climate change during the Quaternary played an important role in the distribution of extant plants. Herein, cone scales of Cedrus (Pinaceae) were uncovered from the Upper Pliocene Sanying Formation, Longmen Village, Yongping County of Yunnan Province in southwestern China. Detailed comparisons show that these fossils all belong to the genus Cedrus (Pinaceae), and a new species is proposed, Cedrus angusta sp. nov. This find expands the known distribution of Cedrus during the Late Pliocene to Yunnan, where the genus no longer exists in natural forests. Based on the analysis of reconstructed Neogene climate data, we suggest that the intensification of the East Asian winter monsoon during the Quaternary may have dramatically increased seasonality and given rise to a much drier winter in Yunnan. Combined with information on Cedrus fossil records and its seed physiology, we conclude that the intensification of a drier climate after the Late Pliocene may have prevented the survival of Cedrus seedlings, leading to the eventual disappearance of Cedrus in western Yunnan. This study indicates that the topography in southwestern China acted as a vital refuge for many plants during the Quaternary, but that other species gradually disappeared due to the intensification of the monsoonal climate.

  12. Mapping surface tidal currents and Changjiang plume in the East China Sea from Geostationary Ocean Color Imager

    NASA Astrophysics Data System (ADS)

    Hu, Zifeng; Wang, Dong-Ping; Pan, Delu; He, Xianqiang; Miyazawa, Yasumasa; Bai, Yan; Wang, Difeng; Gong, Fang

    2016-03-01

    The spatial pattern of the semidiurnal M2 tidal currents in the East China Sea (ECS) is mapped from the Geostationary Ocean Color Imager (GOCI), taking advantage of the satellite's unique 8 hourly local daytime sequential images. The GOCI-derived surface M2 tidal currents are validated with a comprehensive set of twenty-eight surface drifters and four mooring observations. The agreement is outstanding with the error variance less than 10% of the total variance. The gridded GOCI-derived tidal currents are also in good agreement with the Oregon State University (OSU) high-resolution regional tidal model of the China Seas. The detided mean flow shows a strong Changjiang plume extending hundreds of kilometers offshore, in agreement with the concurrent satellite sea surface temperature (SST) and sea surface salinity (SSS) distributions. The observed surface currents are compared with the daily mean flows derived from the Japan Coastal Ocean Predictability Experiment (JCOPE2). The model results are consistent with the observations, showing the sensitivity of Changjiang plume to wind forcing. The study clearly demonstrates the utility of geostationary satellite in mapping the surface currents over a wide (˜400 km), tidally dominated continental shelf.

  13. Impact of urban land-use change in eastern China on the East Asian subtropical monsoon: A numerical study

    NASA Astrophysics Data System (ADS)

    Yu, Rong; Jiang, Zhihong; Zhai, Panmao

    2016-04-01

    The effect of urban land-use change in eastern China on the East Asian subtropical monsoon (EASTM) is investigated by using the Community Atmosphere Model version 5.1. Comparison of the results between the urban expansion and reference experiments shows that with the urban expansion, the land surface energy balance alters: surface net radiation and sensible heat fluxes enhance while the latent heat fluxes reduce. As a result, a significant increase in surface air temperature over eastern China is detected. The urban land-use change contributes to a change in the zonal land-sea temperature difference (LSTD), leading to a delay in the time when LSTD changes from positive to negative, and vice versa. Additionally, the onset and retreat dates of the EASTM are also delayed. Meanwhile, the rise in surface air temperature leads to formation of abnormal northerly air flows, which may be the reason for the slower northward movement of the EASTM and a more southward location of its northern boundary.

  14. Interdecadal Variations of East Asian Monsoon as Inferred by Tree-ring Data From Northeastern Qaidam Basin, Northwestern China

    NASA Astrophysics Data System (ADS)

    Shao, X.; Huang, L.; Yin, Z.; Guo, Q.

    2006-12-01

    East Asian monsoon is crucial for modulating the climate in China. Especially, the summer monsoon is closely related to the severe flood and drought events in eastern China. To study the characteristics of summer monsoon a long-term record is needed. In this study we attempted to examine the interdecadal variations of East Asian monsoon by using tree-ring data. The summer monsoon index (Ism) for the period of 1873- 2000 was calculated using sea level pressure data. Firstly, we calculated the difference (ΔP) of the sea level pressure between the land (110ºE) and sea (160ºE) from 10ºN to 50ºN with 5º intervals. Then the ΔP values that are smaller than or equal to -5 hPa in June, July and August were summed and defined as the Ism. By this definition Ism values greater than 1.0 represent strong monsoon conditions, and vice versa. Sea level pressure data prior to 1951 were obtained from the Meteorological Office of United Kingdom, and that afterwards were from the NCEP data set. The tree ring data of Qilian junipers (Sabina przewalskii Kom.) are from the northeastern part of the Qaidam Basin, located along the northeastern margin of the Qinghai-Tibetan Plateau. These tree-ring data have been used to reconstruct local precipitation and soil moisture conditions. Previous studies have revealed that there was a teleconnection in rainfall between eastern China and the Qinghai-Tibetan Plateau. We examined the relationships of the ring-width series with the Ism series over the common period of 1873-2000 AD. We found that the tree-ring widths were statistical significantly correlated with Ism. These negative correlations increased significantly after a low-pass filter was used for both data sets, indicating very good potential for reconstruction of low-frequency variations of Ism in the past. Variability of the Ism series and ring-width series were examined using power spectrum analysis and wavelet transformation. The reconstructed Ism values during the period 1440

  15. Learning Cities in East Asia: Japan, the Republic of Korea and China

    ERIC Educational Resources Information Center

    Han, SoongHee; Makino, Atsushi

    2013-01-01

    Lifelong learning cities emerged in Japan in the 1980s and 1990s; in the Republic of Korea in the 2000s and 2010s; and in China mostly from 2000 onwards. They were a countermeasure to the increasing challenges of global as well as post-industrial uncertainties at the turn of the century, when cities were trying to find governmental instruments to…

  16. To promote peaceful and collaborative resolution of maritime territorial disputes in the South China Sea and its environs and other maritime areas adjacent to the East Asian mainland.

    THOMAS, 112th Congress

    Rep. Faleomavaega, Eni F. H. [D-AS-At Large

    2012-08-02

    09/12/2012 Committee Agreed to Seek Consideration Under Suspension of the Rules, (Amended) by Unanimous Consent. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  17. GIS/RS-based Integrated Eco-hydrologic Modeling in the East River Basin, South China

    NASA Astrophysics Data System (ADS)

    Wang, Kai

    Land use/cover change (LUCC) has significantly altered the hydrologic system in the East River (Dongjiang) Basin. Quantitative modeling of hydrologic impacts of LUCC is of great importance for water supply, drought monitoring and integrated water resources management. An integrated eco-hydrologic modeling system of Distributed Monthly Water Balance Model (DMWBM), Surface Energy Balance System (SEBS) was developed with aid of GIS/RS to quantify LUCC, to conduct physically-based ET (evapotranspiration) mapping and to predict hydrologic impacts of LUCC. To begin with, in order to evaluate LUCC, understand implications of LUCC and provide boundary condition for the integrated eco-hydrologic modeling, firstly the long-term vegetation dynamics was investigated based on Normalized Difference Vegetation Index (NDVI) data, and then LUCC was analyzed with post-classification methods and finally LUCC prediction was conducted based on Markov chain model. The results demonstrate that the vegetation activities decreased significantly in summer over the years. Moreover, there were significant changes in land use/cover over the past two decades. Particularly there was a sharp increase of urban and built-up area and a significant decrease of grassland and cropland. All these indicate that human activities are intensive in the East River Basin and provide valuable information for constructing scenarios for studying hydrologic impacts of LUCC. The physically-remote-sensing-based Surface Energy Balance System (SEBS) was employed to estimate areal actual ET for a large area rather than traditional point measurements . The SEBS was enhanced for application in complex vegetated area. Then the inter-comparison with complimentary ET model and distributed monthly water balance model was made to validate the enhanced SEBS (ESEBS). The application and test of ESEBS show that it has a good accuracy both monthly and annually and can be effectively applied in the East River Basin. The results of

  18. Overall view of tower and adjacent aircraft shelters on flight ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Overall view of tower and adjacent aircraft shelters on flight line. View to east. - Plattsburgh Air Force Base, Security Guard Tower, Florida Street at Aircraft Shelters Area, Plattsburgh, Clinton County, NY

  19. Using International Law to Defuse Current Controversies in the South and East China Seas

    DTIC Science & Technology

    2015-02-01

    conditions for accepting arbitration and the positive outcomes in the arbitral decisions can apply to other, similar disputes in the neighboring South and...above position is consistently held by the Chinese Government and is widely known by the international community.” Had this statement said something... position would have been at least somewhat more tenable in international legal forums. 11 “New Chinese Map Gives Greater Plan to South China Sea Claims

  20. Fire and flood management of coastal swamp enabled first rice paddy cultivation in east China.

    PubMed

    Zong, Y; Chen, Z; Innes, J B; Chen, C; Wang, Z; Wang, H

    2007-09-27

    The adoption of cereal cultivation was one of the most important cultural processes in history, marking the transition from hunting and gathering by Mesolithic foragers to the food-producing economy of Neolithic farmers. In the Lower Yangtze region of China, a centre of rice domestication, the timing and system of initial rice cultivation remain unclear. Here we report detailed evidence from Kuahuqiao that reveals the precise cultural and environmental context of rice cultivation at this earliest known Neolithic site in eastern China, 7,700 calibrated years before present (cal. yr bp). Pollen, algal, fungal spore and micro-charcoal data from sediments demonstrate that these Neolithic communities selected lowland swamps for their rice cultivation and settlement, using fire to clear alder-dominated wetland scrub and prepare the site for occupation, then to maintain wet grassland vegetation of paddy type. Regular flooding by slightly brackish water was probably controlled by 'bunding' to maintain crop yields. The site's exploitation ceased when it was overwhelmed by marine inundation 7,550 cal. yr bp. Our results establish that rice cultivation began in coastal wetlands of eastern China, an ecosystem vulnerable to coastal change but of high fertility and productivity, attractions maximized for about two centuries by sustained high levels of cultural management of the environment.

  1. Characterizing distributions, composition profiles, sources and potential health risk of polybrominated diphenyl ethers (PBDEs) in the coastal sediments from East China Sea.

    PubMed

    Wang, Guoguang; Peng, Jialin; Zhang, Dahai; Li, Xianguo

    2016-06-01

    Sediment samples (n = 20) were collected from Yangtze River Estuary (YRE) and the adjacent East China Sea (ECS) inner shelf to explore spatial and temporal distributions, environmental fate, sources and potential health risk of polybrominated diphenyl ethers (PBDEs). Concentrations of BDE-209 and total 7 PBDEs (without BDE-209; ∑7PBDEs) ranged from 62.3 to 1758 pg g(-1) and from 36.9 to 233.6 pg g(-1) dry weight, respectively; both of the highest values occurred near the city of Wenzhou. Concentrations of BDE-209 and ∑7PBDEs both indicated a decreasing trend from inshore areas toward outer shelf. Significantly positive linear correlations were only observed between logBDE-183 concentrations and TOC/grain size (r(2) = 0.6734 and 0.5977 for TOC and grain size, respectively) as well as BDE-209 and TOC/grain size (r(2) = 0.4137 and 0.5332 for TOC and grain size, respectively) in the north of 28(°)N, indicating that YR had significant influence on the distribution of higher brominated congeners only in the north part. Depth profiles of PBDEs in a sediment core P01 (n = 1, m = 11) collected from YRE showed that the input of BDE-209 gradually increased from 1930 to 2010, while the levels of ∑7PBDEs peaked in 1986 and obviously decreased in recent years. Partial Least-Squares Regression (PLSR) revealed that PBDEs in the coastal ECS were mainly from direct discharge of local anthropogenic activities (80.7%), followed by surface runoff of contaminated soils (15.1%), microbial degradation after sedimentation (2.6%) and photodegradation during atmospheric transportation (1.6%). The cancer risk of human exposure to BDE-209 at the 95% confidence level was 3.09 × 10(-7), 1.67 × 10(-7) and 8.86 × 10(-7) for children, teens and adults, respectively, significantly lower than the threshold level (10(-6)). Hazard index (HI) calculated for non-cancer risk was also far less than 1 for the three groups, suggesting no non-cancer risk.

  2. Stable isotope ratios reveal food source of benthic fish and crustaceans along a gradient of trophic status in the East China Sea

    NASA Astrophysics Data System (ADS)

    Chang, Ni-Na; Shiao, Jen-Chieh; Gong, Gwo-Ching; Kao, Shuh-Ji; Hsieh, Chih-hao

    2014-08-01

    The East China Sea (ECS) receives large quantities of particulate organic matter (POM) and inorganic nutrients transported from the Changjiang (Yangtze River), which have produced high productivity in the northwestern ECS. This study evaluated potential contributions of terrigenous POM (allochthonous food source) and nutrient-induced marine production (autochthonous source) to the ECS benthic ecosystem by analyzing stable isotopic compositions of phytoplankton, zooplankton, benthic crustaceans and fish. Benthic consumers exhibited δ13C values similar to those of their autochthonous food sources (i.e., phytoplankton and zooplankton), revealing their major reliance on marine production. In contrast, the δ13C values of benthic fish (-19.6‰ to -13.5‰) and crustaceans (-18.9‰ to -15.0‰) were much higher than that of terrigenous POM (-25.7‰), which generally accounted for less than 20% of the most fish diet. Phytoplankton and zooplankton generally exhibited higher δ13C values at eutrophic and highly productive inshore sites than at oligotrophic offshore sites. This enrichment of inshore δ13C values was mainly attributed to lower photosynthetic fractionation during algal blooms, an effect that was further enhanced during flood period of the Changjiang. The δ13C values of demersal fish assemblages were also significantly higher at inshore sites and decreased seaward. However, fish δ15N values and their estimated trophic levels showed relatively small spatial variation. The disproportionate variations in δ13C and δ15N values suggested that the enriched C isotopic signatures derived from an elevated δ13C baseline of the inshore food web instead of trophic enrichment of the isotopic ratios. The significantly positive correlations between concentrations of chlorophyll a and nutrients versus fish δ13C provided further evidence for the use of pelagic algal bloom materials by inshore consumers. The isotopic and oceanographic survey data suggested that

  3. Influence of ENSO on precipitation in the East River basin, south China

    NASA Astrophysics Data System (ADS)

    Zhang, Qiang; Li, Jianfeng; Singh, Vijay P.; Xu, Chong-Yu; Deng, Jingyun

    2013-03-01

    A majority of the literature analyzing the role of El Niño-Southern Oscillation (ENSO) and other teleconnections has focused on summer precipitation and on global and regional scales. Seasonal precipitation, occurring at local scale (<50,000 km2; i.e., a size of one grid cell of a typical global climate model), is of considerable importance for flood mitigation, water supply, and water resources management. In view of the relative absence of studies exploring the forces driving local precipitation, the present study examines this precipitation regime (represented by monthly precipitation data for a period of 1956-2005 from 21 gauge stations in the East River basin) as a response to well-known determining factors, i.e., Southern Oscillation Index (SOI), El Niño Modoki index (EMI), and sea surface temperature anomalies (SSTA) of Niño 1 + 2, Niño 3, Niño 4, and Niño 3.4. To achieve the goal of the study, three types of ENSO events were defined: eastern Pacific warming (EPW), central Pacific warming (CPW), and eastern Pacific cooling (EPC). Mann-Whitney U test was applied to assess whether the probabilistic behavior of precipitation in the ENSO period was different from that in the normal period. The Pearson correlation coefficient was calculated to investigate the relations between areal precipitation in the East River basin and the above-mentioned ENSO indices. Results indicated that (1) EPW caused more precipitation in autumn and winter, but less precipitation in summer. EPW even brought about extremely heavy precipitation in summer and winter. (2) CPW caused less precipitation in spring, autumn, and the annual totals. Sometimes, CPW might bring about heavy precipitation. The precipitation pattern in summer in CPW was different from the normal years. (3) EPC caused more precipitation in autumn and less precipitation in spring and winter. The middle East River basin is the region where precipitation has decreased most severely due to EPC. (4) SSTA, SOI, and EMI

  4. [Area changes of emergent herbaceous wetlands in relation to water level in East Dongting Lake, China in 1989-2011].

    PubMed

    Tang, Yue; Xie, Yong-Hong; Li, Feng; Chen, Xin-Sheng

    2013-11-01

    Based on multi-temporal Landsat MSS/TM/ETM+ images, and by using decision tree method, this paper extracted the areas of emergent herbaceous wetlands with different water levels in 1989-2011 in the East Dongting Lake, China. The change characteristics and change trends of the emergent herbaceous wetlands areas were investigated based on the DEM data and the daily water level data from the Chenglingji Hydrological Station. The area of the emergent herbaceous wetlands was significantly affected by water level (R2 = 0.875, P < 0.001), presenting a significant linear relationship between the two. Moreover, the emergent herbaceous wetlands area decreased with increasing water level. The higher the water level, the smaller the effects of the water level on the emergent area were. The emergent area changed regularly with water level. In January-July, water level increased, and the emergent area decreased; in July-December, it was opposite. In 1989-2011, the areas of emergent herbaceous wetlands had a continual increase. The newly emergent herbaceous wetlands area was mainly transformed from mudflat. The emergent herbaceous wetlands expansion was the co-effects of the increase of the emergent herbaceous wetlands areas at different elevations, and the rapid expansion of the emergent herbaceous wetlands in low bottomland (22-25 m of Yellow Sea elevation) played the most important role in the expansion. The change of water level at different elevations was the dominant cause for the changes of emergent herbaceous wetlands areas in the East Dongting Lake in the past 20 years.

  5. Assessing depth-integrated phytoplankton biomass in the East China Sea using a unique empirical protocol to estimate euphotic depth

    NASA Astrophysics Data System (ADS)

    Koshikawa, Hiroshi; Higashi, Hironori; Hasegawa, Toru; Nishiuchi, Kou; Sasaki, Hiroaki; Kawachi, Masanobu; Kiyomoto, Yoko; Takayanagi, Kazufumi; Kohata, Kunio; Murakami, Shogo

    2015-02-01

    The Changjiang (Yangtze) River plume has a direct impact on phytoplankton biomass in the East China Sea (ECS). The present study aimed to analyze the spatial distribution of depth-integrated chlorophyll a (Chl-a) concentrations from the surface to the euphotic depth (Ze; ∑ ChlZe) using samples collected at 50 stations in the ECS during a cruise in June 2007. However, spatial coverage was limited because the Ze, obtained from radiometric measurement of the vertical diffuse attenuation of solar irradiance, was only available at the 20 daytime stations. To address this limitation, it was determined that Ze could be expressed empirically using the vertical means of Chl-a concentration, turbidity, and salinity in the euphotic zone. Using this relationship, the potential value of Ze at night-time or low-light stations was calculated, and a dataset of (∑ ChlZe) for the entire research area was obtained. A low salinity surface water mass (LSSW) was identified on the eastern continental shelf (125.0°-126.5°E, 30.0°-31.0°N), probably part of the Yellow Sea Mixed Water, but clearly influenced by Changjiang Diluted Water (CDW) extending from the west. The Taiwan Current Warm Water mass (TCWW) was located to the south of the LSSW. Other oceanic water masses, including Kuroshio Surface Water, were located to the east of the LSSW. The means of the Ze and ∑ ChlZe in the LSSW were significantly shallower and higher, respectively, compared with the TCWW and other oceanic water masses (p < 0.01). The present study suggests that the extension of the Changjiang River plume beyond the CDW affects the phytoplankton biomass on the eastern continental shelf of the ECS, more than 300 km from the river mouth.

  6. Three Gorges Dam controls sediment coarsening of the mud patch on the inner East China Sea shelf

    NASA Astrophysics Data System (ADS)

    Miao, Anyang; Chu, Zhongxin; Li, Yingkun

    2016-06-01

    The well-known Three Gorges Dam (TGD) within the Yangtze catchment launched its operation in 2003. The effect of the TGD operation on the sediment size on the East China Sea shelf is rarely known. High resolution (0.5 cm sampling) grain size analysis and 137Cs and 210Pb dating of the DH8-1 core were conducted with core collected from the distal part of a main sink for the modern Yangtze sediment entering the sea, the Min-Zhe Coastal Mud Deposits (MZCMD) on the inner East China Sea shelf. The 137Cs dating results show that the core DH8-1 formed during 1946-2012 with a mean deposition rate of 0.65 cm yr-1, indicating that the 0.5 cm sampling for grain size analysis in this local area could reflect environmental changes generally on a one-year time scale. The mean grain size of DH8-1 core sediment that deposited after 2003 is significantly larger than that deposited during 1988-2002. After ruling out other possible factors, we infer that the sediment coarsening of DH8-1 core after 2003 is attributed to the TGD operation which causes the erosion of the Yangtze subaqueous delta. Specifically, the TGD operation significantly intensifies the declining trend of the Yangtze sediment loads to the sea despite no decreased water discharge, which results in extensive erosion of the Yangtze subaqueous delta. The relatively coarse sediment of the subaqueous delta is eroded and resuspended by ocean dynamics and then transported by coastal current, finally depositing on the MZCMD area. In addition, the general sediment fining of core DH8-1 that deposited during 1988-2002, comparing with 1946-1987, is mainly caused by dam construction and soil and water conservation within the Yangtze catchment. Our findings are helpful for better understanding the effects of such a huge dam as the TGD on a sediment sink like the MZCMD of such a large river as the Yangtze River.

  7. [Effect of stock abundance and environmental factors on the recruitment success of small yellow croaker in the East China Sea].

    PubMed

    Liu, Zun-lei; Yuan, Xing-wei; Yang, Lin-lin; Yan, Li-ping; Zhang, Hui; Cheng, Jia-hua

    2015-02-01

    Multiple hypotheses are available to explain recruitment rate. Model selection methods can be used to identify the best model that supports a particular hypothesis. However, using a single model for estimating recruitment success is often inadequate for overexploited population because of high model uncertainty. In this study, stock-recruitment data of small yellow croaker in the East China Sea collected from fishery dependent and independent surveys between 1992 and 2012 were used to examine density-dependent effects on recruitment success. Model selection methods based on frequentist (AIC, maximum adjusted R2 and P-values) and Bayesian (Bayesian model averaging, BMA) methods were applied to identify the relationship between recruitment and environment conditions. Interannual variability of the East China Sea environment was indicated by sea surface temperature ( SST) , meridional wind stress (MWS), zonal wind stress (ZWS), sea surface pressure (SPP) and runoff of Changjiang River ( RCR). Mean absolute error, mean squared predictive error and continuous ranked probability score were calculated to evaluate the predictive performance of recruitment success. The results showed that models structures were not consistent based on three kinds of model selection methods, predictive variables of models were spawning abundance and MWS by AIC, spawning abundance by P-values, spawning abundance, MWS and RCR by maximum adjusted R2. The recruitment success decreased linearly with stock abundance (P < 0.01), suggesting overcompensation effect in the recruitment success might be due to cannibalism or food competition. Meridional wind intensity showed marginally significant and positive effects on the recruitment success (P = 0.06), while runoff of Changjiang River showed a marginally negative effect (P = 0.07). Based on mean absolute error and continuous ranked probability score, predictive error associated with models obtained from BMA was the smallest amongst different

  8. A new genus and new species of Potamidea (Crustacea: Decapoda: Brachyura: Potamoidae), the first stygomorphic cave crab known from China and East Asia.

    PubMed

    Huang, Chao; Shih, Hsi-Te; Ng, Peter K L

    2017-02-15

    A new genus and species of freshwater crab, Diyutamon cereum n. gen., n. sp., is described from a cave in Guizhou, China. This is the first record of a true stygomorphic crab from China and East Asia, possessing pale body coloration, strongly reduced eyes, and long ambulatory legs. While superficially similar to Chinapotamon Dai & Naiyanetr, 1994, and Tiwaripotamon Bott, 1970, the new genus possesses a diagnostic combination of carapace, ambulatory leg, thoracic sternal, and male abdominal characters that easily distinguishes it from other genera. Molecular data derived from the mitochondrial 16S rDNA supports the establishment of the new genus.

  9. Two new benthic Euphilomedes Kornicker, 1967 (Ostracoda, Myodocopida, Philomedidae) from the Taiwan Strait (East China Sea)

    PubMed Central

    Chen, Xiaoyin; Chen, Ruixiang; Lin, Jinghong; Wang, Yu; Ye, Youyin

    2017-01-01

    Ostracods are small bivalved crustaceans widely distributed in aquatic environments and in total 99 species have been recorded in genus Euphilomedes Kornicker, 1967. In this study, we further describe two new species of benthic ostracods in this genus, Euphilomedes liuruiyii sp. nov. and Euphilomedes pentacanthos sp. nov., collected from the Taiwan Strait in China. These two species can be easily distinguished from their congeners by some crucial morphological characteristics, including the carapace shape, the numbers of main and secondary furcal claws, and their arrangement of furcal claws. In addition the first antenna, endopod of second antenna, frontal organ, mandible and the seventh limb also differentiate these two species from related species.

  10. Establishment of trophic continuum in the food web of the Yellow Sea and East China Sea ecosystem: insight from carbon and nitrogen stable isotopes.

    PubMed

    Cai, Deling; Li, Hongyan; Tang, Qisheng; Sun, Yao

    2005-12-01

    Stable carbon and nitrogen isotope ratios (delta (13)C and delta (15)N) are used to study the trophic structure of food web in the Yellow Sea and East China Sea ecosystem. The trophic continuum of pelagic food web from phytoplankton to top preyer was elementarily established, and a trophic structure diagram in the Yellow Sea and East China Sea was outlined in combination with carbon isotopic data of benthic organisms, which is basically consistent with and makes some improvements on the simplified Yellow Sea food web and the trophic structure diagram drawn based on the biomass of main resource population during 1985-1986. This result indicates that the stable isotope method is a potential useful means for further studying the complete marine food web trophic continuum from viruses to top predators and food web stability.

  11. Use of Stochastic Modeling of Stratigraphic Relationships in High Resolution Seismic Reflection Data for Prediction of the Distribution of Acoustic and Geotechnical Property Variability in Near Surface Sediments on the East China Sea Continental Margin

    DTIC Science & Technology

    2004-09-01

    Sequence Stratigraphy of the East China Sea: Where are the Incised Valleys?, In J.M. Armentrout and N.C. Rosen, (eds), Sequence Stratigraphic Models for...Bartek, L.R., 2002, The Sequence Stratigraphy of the East China Sea: Where are the Incised Valleys? Invited Paper, In J.M. Armentrout (ed.), Proceedings of...C. C., and Bartek, L . R., Pearce, P., 1999, Reservoir Facies Distribution within Stacked Channel Sands of Falling-Stage/Lowstand Systems on

  12. Multiple Suppression and Imaging of Marine Seismic Data from The Shallow Water Area in Southern East China Sea Shelf Basin

    NASA Astrophysics Data System (ADS)

    Shi, J.; Luan, X.; Yang, C.

    2015-12-01

    Neither surface-related multiple elimination(SRME) nor predictive de-convolution method is effective to suppress the multiple of marine seismic data from the shallow water area. The former method needs the accurate reflection of seafloor, which is mixed with the direct wave in the near offset range. The other one could probably lose the primary wave when applied to the shallow water seismic data. We introduced the new method: deterministic water-layer de-multiple method (DWD) which is capable for the poor extrapolate result of near-offset traces. Firstly, the data shifts as downward continuation in tau-p domain with a water-layer period and the multiple model will be obtained. Then, the original seismic subtracts adaptively with the multiple model. Finally, we would get the de-multiple data after inverse tau-p transform. Marine seismic real data is from southern part of East China Sea Shelf Basin. This area has become the potential target for marine hydrocarbon exploration, it is located in the junction of the Eurasian plate pacific plate and Indian plate. Because the average water depth is less than 100 meters, seismic data contains abundant of multiple, especially the surface-related multiple. As a result it is difficult to distinguish the strata structure clearly. We used DWD approach to remove the water-layer multiple, cut off the seafloor reflection events and then suppressed the residual surface-related multiple by the traditional SRME. At last , the radon transform was applied to eliminate the multiple with long period . With these steps, we suppressed the multiple of marine seismic data from this area effectively. After multiple is removed , we acquired more accurate velocity to build the velocity model of migration. With the pre-stack migration technique, reflections from each geological period are shown clearly in the seismic section. This work was supported by the National Science Foundation of China(grant no. 41476053).

  13. [Eco-environmental quality assessment of Luoyuan Bay, Fujian province of East China based on biotic indices].

    PubMed

    Wu, Hai-Yan; Chen, Ke-Liang; Zhang, Ping; Fu, Shi-Feng; Hou, Jian-Ping; Chen, Qing-Hui

    2013-03-01

    In this paper, two types of eco-environmental quality assessment indices that have been successively applied abroad, i.e., the AZTI marine biotic index (AMBI) and BENTIX index based on the ecological sensitivity of benthos and the multivariate-AMBI (M-AMBI), a multivariate index integrating AMBI, Shannon Index H', and species richness, were applied to assess the eco-environmental quality of Luoyuan Bay, Fujian Province of East China, and the assessment results were compared with those by the H', an index based on community structure, which is often applied in China, aimed to test the applicability of these indices to the Bay, and to provide reference in selecting the indices for assessing our coastal eco-environment quality. Similar assessment results were obtained by applying AMBI and BENTIX index, and M-AMBI and H'. At most stations (13 of 16), the assessment results by applying AMBI and BENTIX index, M-AMBI and H' were coincident, respectively; while at the other 3 stations, the assessment grade was high or good based on AMBI and BENTIX index, but moderate based on M-AMBI and H'. Taking account of the richness, individual abundance, and ecological group composition of the benthos in Luoyuan Bay, the assessment results based on M-AMBI and H' could be more reasonable. It was suggested that for the Luoyuan Bay which has a high level of eutrophication and low organic matter enrichment in sediment and is dominated by sensitive benthos species, M-AMBI and H' could be more applicative and objective than AMBI and BENTIX index in assessing its eco-environmental quality.

  14. Development of a Plug-and-Play Monitoring System for Cabled Observatories in the East China Sea

    PubMed Central

    Yu, Yang; Xu, Huiping; Xu, Changwei

    2015-01-01

    Seafloor observatories enable long term, continuous and multidisciplinary observations, promising major breakthroughs in marine environment research. The effort to remotely control in situ multidisciplinary equipment performing individual and cooperative tasks is both a challenge and a guarantee for the stable operations of functional observatories. With China starting to establish ocean observatory sensor networks, in this study we describe a monitoring system for cabled observatories in the East China Sea (ESOMS) that enables this effort in a plug and play way. An information oriented monitoring architecture for ESOMS was first introduced, derived from a layered control model for ocean observatory sensor network. The architecture contained three components and enabled bidirectional information flow of observation data and commands, based on which architecture components were designed to enable plug-and-play control within related model layers. A control method enabled by general junction box (GJB) and ocean sensor markup language (OSML) was thus proposed as the plug-and-play solution for implementing ESOMS. The GJB-OSML enabled control method (GOE Control Method) mainly actualized two processes, one of which was that the in situ GJB interfaced and represented every attached sensor as a Sensing Endpoint in the cabled observatory network. The other process was that the remote ESOMS utilized the same IP/Port related information modeled by OSML to create/operate a Function Node acted as agent of the in situ sensor. A case study for using ESOMS in the Xiaoqushan Seafloor Observatory was finally presented to prove its performance and applicability. Given this successful engineering trial, the ESOMS design and implementation could be applicable and beneficial for similar efforts in future construction of seafloor observatory network both at home and abroad. PMID:26213931

  15. Development of a Plug-and-Play Monitoring System for Cabled Observatories in the East China Sea.

    PubMed

    Yu, Yang; Xu, Huiping; Xu, Changwei

    2015-07-23

    Seafloor observatories enable long term, continuous and multidisciplinary observations, promising major breakthroughs in marine environment research. The effort to remotely control in situ multidisciplinary equipment performing individual and cooperative tasks is both a challenge and a guarantee for the stable operations of functional observatories. With China starting to establish ocean observatory sensor networks, in this study we describe a monitoring system for cabled observatories in the East China Sea (ESOMS) that enables this effort in a plug and play way. An information oriented monitoring architecture for ESOMS was first introduced, derived from a layered control model for ocean observatory sensor network. The architecture contained three components and enabled bidirectional information flow of observation data and commands, based on which architecture components were designed to enable plug-and-play control within related model layers. A control method enabled by general junction box (GJB) and ocean sensor markup language (OSML) was thus proposed as the plug-and-play solution for implementing ESOMS. The GJB-OSML enabled control method (GOE Control Method) mainly actualized two processes, one of which was that the in situ GJB interfaced and represented every attached sensor as a Sensing Endpoint in the cabled observatory network. The other process was that the remote ESOMS utilized the same IP/Port related information modeled by OSML to create/operate a Function Node acted as agent of the in situ sensor. A case study for using ESOMS in the Xiaoqushan Seafloor Observatory was finally presented to prove its performance and applicability. Given this successful engineering trial, the ESOMS design and implementation could be applicable and beneficial for similar efforts in future construction of seafloor observatory network both at home and abroad.

  16. Measurements of regional-scale aerosol impacts on cloud microphysics over the East China Sea: Possible influences of warm sea surface temperature over the Kuroshio ocean current

    NASA Astrophysics Data System (ADS)

    Koike, M.; Takegawa, N.; Moteki, N.; Kondo, Y.; Nakamura, H.; Kita, K.; Matsui, H.; Oshima, N.; Kajino, M.; Nakajima, T. Y.

    2012-09-01

    Cloud microphysical properties and aerosol concentrations were measured aboard an aircraft over the East China Sea and Yellow Sea in April 2009 during the Aerosol Radiative Forcing in East Asia (A-FORCE) experiment. We sampled stratocumulus and shallow cumulus clouds over the ocean in 9 cases during 7 flights 500-900 km off the east coast of Mainland China. In this study we report aerosol impacts on cloud microphysical properties by focusing on regional characteristics of two key parameters, namely updraft velocity and aerosol size distribution. First, we show that the cloud droplet number concentration (highest 5%, Nc_max) correlates well with the accumulation-mode aerosol number concentration (Na) below the clouds. We then show that Nc_maxcorrelates partly with near-surface stratification evaluated as the difference between the sea surface temperature (SST) and 950-hPa temperature (SST - T950). Cold air advection from China to the East China Sea was found to bring not only a large number of aerosols but also a dry and cold air mass that destabilized the atmospheric boundary layer, especially over the warm Kuroshio ocean current. Over this high-SST region, greater updraft velocities and hence greater Nc_maxlikely resulted. We hypothesize that the low-level static stability determined by SST and regional-scale airflow modulates both the cloud microphysics (aerosol impact on clouds) and macro-structure of clouds (cloud base and top altitudes, hence cloud liquid water path). Second, we show that not only higher aerosol loading in terms of total aerosol number concentration (NCN, D > 10 nm) but also larger aerosol mode diameters likely contributed to high Ncduring A-FORCE. The mean Nc of 650 ± 240 cm-3was more than a factor of 2 larger than the global average for clouds influenced by continental sources. A crude estimate of the aerosol-induced cloud albedo radiative forcing is also given.

  17. Effects of internal tidal dissipation and self-attraction and loading on semidiurnal tides in the Bohai Sea, Yellow Sea and East China Sea: a numerical study

    NASA Astrophysics Data System (ADS)

    Teng, Fei; Fang, Guohong; Xu, Xiaoqing

    2016-09-01

    A parameterized internal tide dissipation term and self-attraction and loading (SAL) tide term are introduced in a barotropic numerical model to investigate the dynamics of semidiurnal tidal constituents M2 and S2 in the Bohai Sea, Yellow Sea and East China Sea (BYECS). The optimal parameters for bottom friction and internal dissipation are obtained through a series of numerical computations. Numerical simulation shows that the tide-generating force contributes 1.2% of M2 power for the entire BYECS and up to 2.8% for the East China Sea deep basin. SAL tide contributes 4.4% of M2 power for the BYECS and up to 9.3% for the East China Sea deep basin. Bottom friction plays a major role in dissipating tidal energy in the shelf regions, and the internal tide effect is important in the deep water regions. Numerical experiments show that artificial removal of tide-generating force in the BYECS can cause a significant difference (as much as 30 cm) in model output. Artificial removal of SAL tide in the BYECS can cause even greater difference, up to 40 cm. This indicates that SAL tide should be taken into account in numerical simulations, especially if the tide-generating force is considered.

  18. Heavy metal enrichments in the Changjiang (Yangtze River) catchment and on the inner shelf of the East China Sea over the last 150 years.

    PubMed

    Guo, Yanwei; Yang, Shouye

    2016-02-01

    Compositions of heavy metals including Cu, Zn, Cr and Pb in three sediment cores recovered from the lower basin of the Changjiang (Yangtze River) and the inner shelf mud of the East China Sea were analyzed by traditional X-ray florescence (XRF) and XRF Core Scanner. This study aims to investigate the accumulation of heavy metals in the fluvial sediments and to decipher the influence of anthropogenic activities within the large catchment over the last 150 years. The data suggest that the heavy metals, especially Pb and Zn, show obvious enrichments in concentrations since 1950s, and the small and consistent variations of heavy metal concentrations before 1950s can represent geochemical background values. After removing the grain size effect on elemental concentrations, we infer that the sources of heavy metals predominantly come from natural weathering detritus, while human contamination has increased over the last half century. The calculations of both enrichment factor and geoaccumulation index, however, indicate that the pollution of these heavy metals in the fluvial and shelf environments is not significant. The rapid increase in human activities and fast socioeconomic development in the Changjiang catchment and East China over the last five decades accounts for the enrichments of heavy metals in the river and marine sediments. The inner shelf of the East China Sea, as the major sink of the Changjiang-derived fine sediments, provides a high-resolution sediment archive for tracing the anthropogenic impacts on the catchment.

  19. Interior view showing north and east access doors, view facing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view showing north and east access doors, view facing east-northeast - U.S. Naval Base, Pearl Harbor, Temporary Storehouse & Gas Cylinder Storage, Avenue D, adjacent to east side of Facility No. 29, Pearl City, Honolulu County, HI

  20. [Application of carrying capacity assessment in spatial allocation of regional population: a case of Changzhou City of East China].

    PubMed

    Chen, Shuang; Wang, Dan; Li, Guang-Yu; Liu, Deng-E; Wu, Song

    2012-02-01

    Based on the spatial differences in urban ecosystem carrying capacity, and by using geographic information system (GIS) spatial analysis technology and system dynamics (SD) model, this paper ascertained the moderate population size in urban area and its subareas, and presented an alternative method for quantitatively allocate the population. This method was applied in Changzhou, a city with more than three million populations in East China. A SD model consisted of population, economy, land and environment modules for the city was established and scenario analysis was made. The results showed that under the requirements of satisfying both economic development and environmental protection, the total population in the city in 2050 would reach nearly 4 million, and according to the differences in the urban ecosystem carrying capacity, a spatial allocation pattern of 2.4 million populations in main city and 150000-400000 populations in each of 5 new towns was proposed. This study could provide scientific support for the spatial allocation of population and economy in country land development and management.

  1. Long-Term Study of the Relationship between Precipitation and Aquatic Vegetation Succession in East Taihu Lake, China.

    PubMed

    Zhang, Yehui; Yang, Na; Xu, Jiawei; Yin, Yixing

    2017-01-01

    Based on long-term rainfall measurements (1956-2012), water level records (1956-2006), and aquatic plants field survey data (1960-2014), the relationship between precipitation and aquatic vegetation succession in east Taihu Lake, China, is studied. Neither abrupt changes nor any trends were found in the annual rainfall series in Taihu Lake during the studied period (1956-2012). However, for seasonal variations, statistically significant decreases are found in spring and autumn, while the rainfall in winter exhibits statistically significant increase. No significant trend was obtained in summer. A "dry" period was detected in our studied period (1963/1964~1978/1979). Total annual rainfall was significantly positively correlated to the number of rain-days (r = 0.59) and the water level (r = 0.84). Our results indicate that the variations of rainfall and water level may have an impact on the aquatic plants in Taihu Lake. The dry period may be not suitable for the growth of the aquatic plants. All aquatic plants in Taihu Lake were dramatically reduced in the dry period, especially for submerged macrophytes and floating-leaf macrophytes. Our results may be helpful for the aquatic restoration in the future.

  2. Seasonal variation of polybrominated diphenyl ethers in PM2.5 aerosols over the East China Sea.

    PubMed

    Li, Yuanyuan; Lin, Tian; Wang, Fengwen; Ji, Tianyi; Guo, Zhigang

    2015-01-01

    PM2.5 aerosol samples were collected from a receptor site in the East China Sea (ECS) to explore the seasonal variation and sources of polybrominated diphenyl ethers (PBDEs). The concentrations of BDE-209 and total 11 PBDEs without BDE-209 (∑11PBDEs) were 7.1±6.8 and 0.97±0.52 pg m(-3), respectively. A distinct seasonal variation was observed for both BDE-209 and ∑11PBDEs, that higher concentrations in winter and spring dominated by the northwesterly winds while lower concentrations in autumn and summer when the southeasterly winds prevailed, suggesting a significant role of continental outflow on the elevated concentrations of PM2.5-bound PBDEs in winter and spring. Besides, the strong dust storm could increase the load of PBDEs in continental outflow to the atmosphere over ECS. Differently, due to the absence of continental outflow in autumn and summer, the good correlations between BDE-209 and ∑11PBDEs implied a potential contribution of the low brominated PBDEs from photoproducts of BDE-209 in high temperature circumstance, while the good correlations of OC with BDE-209 and BDE-99 suggested a significant role of OC in the occurrence of PM2.5-bound PBDEs over ECS.

  3. [Responses of functional diversity of aquatic insect community to land use change in middle reach of Qiantang River, East China].

    PubMed

    Zhang, Lian-Bo; Liu, Dong-Xiao; Liu, Shuo-Ru; Zhang, Yong; Tong, Xiao-Li; Wang, Bei-Xin

    2013-10-01

    Based on the biological traits such as life history, resistance ability against environmental disturbance, and physiological characteristics of aquatic insects, and by using the fourth-corner statistical method, this paper studied the responses of the functional diversity of aquatic insect community to land use change in the middle reach of Qiantang River, Zhejiang Province of East China. For the test aquatic insect community, some of its biological traits were sensitive to land use change, and altered along human disturbance gradients as expected. With the increasing intensity of human disturbance, the maximal insect body length decreased gradually, the dominant respiration pattern evolved from gill respiration to tegument respiration, and the abundance of burrowers increased significantly. At the same time, the functional diversity measured as Rao's quadratic entropy was significantly higher in reference sites than in disturbed sites (P < 0.001), demonstrating that the changes in the functional diversity of the aquatic community were mainly induced by the land use change caused by human activities, which resulted in the decline of stream water quality and habitat quality and the variations of aquatic insect community composition and biological traits. The aquatic insect biological traits and functional diversity could be the potentially effective indicators in the stream health assessment in the future.

  4. Long-Term Study of the Relationship between Precipitation and Aquatic Vegetation Succession in East Taihu Lake, China

    PubMed Central

    Xu, Jiawei; Yin, Yixing

    2017-01-01

    Based on long-term rainfall measurements (1956–2012), water level records (1956–2006), and aquatic plants field survey data (1960–2014), the relationship between precipitation and aquatic vegetation succession in east Taihu Lake, China, is studied. Neither abrupt changes nor any trends were found in the annual rainfall series in Taihu Lake during the studied period (1956–2012). However, for seasonal variations, statistically significant decreases are found in spring and autumn, while the rainfall in winter exhibits statistically significant increase. No significant trend was obtained in summer. A “dry” period was detected in our studied period (1963/1964~1978/1979). Total annual rainfall was significantly positively correlated to the number of rain-days (r = 0.59) and the water level (r = 0.84). Our results indicate that the variations of rainfall and water level may have an impact on the aquatic plants in Taihu Lake. The dry period may be not suitable for the growth of the aquatic plants. All aquatic plants in Taihu Lake were dramatically reduced in the dry period, especially for submerged macrophytes and floating-leaf macrophytes. Our results may be helpful for the aquatic restoration in the future. PMID:28261516

  5. Regional variations in the diversity and predicted metabolic potential of benthic prokaryotes in coastal northern Zhejiang, East China Sea

    PubMed Central

    Wang, Kai; Ye, Xiansen; Zhang, Huajun; Chen, Heping; Zhang, Demin; Liu, Lian

    2016-01-01

    Knowledge about the drivers of benthic prokaryotic diversity and metabolic potential in interconnected coastal sediments at regional scales is limited. We collected surface sediments across six zones covering ~200 km in coastal northern Zhejiang, East China Sea and combined 16 S rRNA gene sequencing, community-level metabolic prediction, and sediment physicochemical measurements to investigate variations in prokaryotic diversity and metabolic gene composition with geographic distance and under local environmental conditions. Geographic distance was the most influential factor in prokaryotic β-diversity compared with major environmental drivers, including temperature, sediment texture, acid-volatile sulfide, and water depth, but a large unexplained variation in community composition suggested the potential effects of unmeasured abiotic/biotic factors and stochastic processes. Moreover, prokaryotic assemblages showed a biogeographic provincialism across the zones. The predicted metabolic gene composition similarly shifted as taxonomic composition did. Acid-volatile sulfide was strongly correlated with variation in metabolic gene composition. The enrichments in the relative abundance of sulfate-reducing bacteria and genes relevant with dissimilatory sulfate reduction were observed and predicted, respectively, in the Yushan area. These results provide insights into the relative importance of geographic distance and environmental condition in driving benthic prokaryotic diversity in coastal areas and predict specific biogeochemically-relevant genes for future studies. PMID:27917954

  6. Age and growth of chub mackerel ( Xcomber japonicus) in the East China and Yellow Seas using sectioned otolith samples

    NASA Astrophysics Data System (ADS)

    Li, Gang; Chen, Xinjun; Feng, Bo

    2008-11-01

    Although chub mackerel ( Scomber japonicus) is a primary pelagic fish species, we have only limited knowledge on its key life history processes. The present work studied the age and growth of chub mackerel in the East China and Yellow Seas. Age was determined by interpreting and counting growth rings on the sagitta otoliths of 252 adult fish caught by the Chinese commercial purse seine fleet during the period from November 2006 to January 2007 and 150 juveniles from bottom trawl surveys on the spawning ground in May 2006. The difference between the assumed birth date of 1st April and date of capture was used to adjust the age determined from counting the number of complete translucent rings. The parameters of three commonly used growth models, the von Bertalanffy, Logistic and Gompertz models, were estimated using the maximum likelihood method. Based on the Akaike Information Criterion ( AIC), the von Bertalanffy growth model was found to be the most appropriate model. The size-at-age and size-at-maturity values were also found to decrease greatly compared with the results achieved in the 1950s, which was caused by heavy exploitation over the last few decades.

  7. Seasonal and spatial variations of macro- and megabenthic community characteristics in two sections of the East China Sea

    NASA Astrophysics Data System (ADS)

    Xu, Yong; Li, Xinzheng; Ma, Lin; Dong, Dong; Kou, Qi; Sui, Jixing; Gan, Zhibin; Wang, Hongfa

    2016-10-01

    In spring and summer 2011, the macro- and megabenthic fauna in two sections of the East China Sea were investigated using an Agassiz net trawl to detect the seasonal and spatial variations of benthic community characteristics and the relation to environmental variables. The total number of species increased slightly from spring (131 species) to summer (133) whereas the percentage of Mollusca decreased significantly. The index of relative importance (IRI) indicated that the top five important species changed completely from spring to summer. Species number, abundance and biomass in summer were significantly higher than in spring, but no significant difference was observed among areas (coastal, transitional and oceanic areas, divided basically from inshore to offshore). Species richness (d), diversity (H') and evenness (J') showed no significant seasonal or spatial variations. Cluster analysis and nMDS ordination identified three benthic communities from inshore to offshore, corresponding to the three areas. Analysis of Similarity (ANOSIM) indicated the overall significant difference in community structure between seasons and among areas. K-dominance curves revealed the high intrinsic diversity in the offshore area. Canonical correspondence analysis showed that the coastal community was positively correlated to total nitrogen and total organic carbon in spring, but negatively in summer; oceanic community was positively correlated to total nitrogen and total organic carbon in both seasons. Species such as Coelorhynchus multispinulosus, Neobythites sivicola, Lepidotrigla alata, Solenocera melantho, Parapenaeus fissuroides, Oratosquilla gonypetes and Spiropagurus spiriger occurred exclusively in the offshore oceanic area and their presence may reflect the influence of the offshore Kuroshio Current.

  8. Macrobenthic community structure and species composition in the Yellow Sea and East China Sea in jellyfish bloom

    NASA Astrophysics Data System (ADS)

    Peng, Songyao; Li, Xinzheng; Wang, Hongfa; Zhang, Baolin

    2014-05-01

    To understand the characteristics of macrobenthic structures and the relationship between environment and benthic assemblages in jellyfish bloom, we studied the macrobenthos and related environmental factors in the coastal waters of the Yellow Sea and East China Sea. Data were collected during two seasonal cruises in April and August of 2011, and analyzed with multivariate statistical methods. Up to 306 macrobenthic species were registered from the research areas, including 115 species of Polychaeta, 78 of Crustacea, 61 of Mollusca, 30 of Echinodermata, and 22 of other groups. Nine polychaete species occurred at frequencies higher than 25% from the sampling stations: Lumbrineris longifolia, Notomastus latericeus, Ninöe palmata, Ophelina acuminata, Nephtys oligobranchia, Onuphis geophiliformis, Glycera chirori, Terebellides stroemii, and Aricidea fragilis. Both the average biomass and abundance of macrobenthos are higher in August (23.8 g/m2 and 237.7 ind./m2) than those in April (11.3 g/m2 and 128 ind./m2); the dissimilarity of macrobenthic structures among stations is as high as 70%. In terms of the dissimilarity values, we divided the stations into four clusters in spring and eight in summer. The ABC curve shows that the macrofauna communities in high jellyfish abundance were not changed. Canonical correspondence analysis showed that depth, temperature, median grain size, total organic carbon of sediment and total nitrogen in sediment were important factors affecting the macrozoobenthic community in the study area.

  9. Phylogenetic diversity of actinobacteria associated with soft coral Alcyonium gracllimum and stony coral Tubastraea coccinea in the East China Sea.

    PubMed

    Yang, Shan; Sun, Wei; Tang, Cen; Jin, Liling; Zhang, Fengli; Li, Zhiyong

    2013-07-01

    Actinobacteria are widely distributed in the marine environment. To date, few studies have been performed to explore the coral-associated Actinobacteria, and little is known about the diversity of coral-associated Actinobacteria. In this study, the actinobacterial diversity associated with one soft coral Alcyonium gracllimum and one stony coral Tubastraea coccinea collected from the East China Sea was investigated using both culture-independent and culture-dependent approaches. A total of 19 actinobacterial genera were detected in these two corals, among which nine genera (Corynebacterium, Dietzia, Gordonia, Kocuria, Microbacterium, Micrococcus, Mycobacterium, Streptomyces, and Candidatus Microthrix) were common, three genera (Cellulomonas, Dermatophilus, and Janibacter) were unique to the soft coral, and seven genera (Brevibacterium, Dermacoccus, Leucobacter, Micromonospora, Nocardioides, Rhodococcus, and Serinicoccus) were unique to the stony coral. This finding suggested that highly diverse Actinobacteria were associated with different types of corals. In particular, five actinobacterial genera (Cellulomonas, Dermacoccus, Gordonia, Serinicoccus, and Candidatus Microthrix) were recovered from corals for the first time, extending the known diversity of coral-associated Actinobacteria. This study shows that soft and stony corals host diverse Actinobacteria and can serve as a new source of marine actinomycetes.

  10. The burial of biogenic silica, organic carbon and organic nitrogen in the sediments of the East China Sea

    NASA Astrophysics Data System (ADS)

    Wang, Lisha; Zhang, Chuansong; Shi, Xiaoyong

    2015-06-01

    We sampled the sediments of the East China Sea during 2005 and 2006, and analysed the contents of the biogenic matters: biogenic silica, organic carbon, and organic nitrogen. From the surface distribution we found the contents of these substances to be in the ranges of 0.72%-1.64%, 0.043%-0.82%, and 0.006%-0.11%, respectively. Their distributions were similar to each other, being high inside the Hangzhou Bay and low outside the bay. The vertical variations of the contents were also similar. In order to discuss the relation between them we analysed the variations of content with depth. They increased in the first 7 cm and then decreased with depth. The peaks were found at depths between 20 to 25 cm. The distribution of carbonate showed an opposite trend to that of biogenic matters. The content of total carbon was relatively stable with respect to depth, and the ratio of high organic carbon to carbonate showed a low burial efficiency of carbonate, which means that the main burial of carbon is organic carbon. In order to discuss the source of organic matters, the ratio of organic carbon to organic nitrogen was calculated, which was 8.01 to 9.65, indicating that the organic matter in the sediments was derived mainly from phytoplankton in the seawater.

  11. Biogeography of the sediment bacterial community responds to a nitrogen pollution gradient in the East China Sea.

    PubMed

    Xiong, Jinbo; Ye, Xiansen; Wang, Kai; Chen, Heping; Hu, Changju; Zhu, Jianlin; Zhang, Demin

    2014-03-01

    Patterns of microbial distribution represent the integrated effects of historical and biological processes and are thus a central issue in ecology. However, there is still active debate on whether dispersal limitation contributes to microbial diversification in strongly connected systems. In this study, sediment samples were collected along a transect representing a variety of seawater pollution levels in the East China Sea. We investigated whether changes in sediment bacterial community structures would indicate the effects of the pollution gradient and of dispersal limitation. Our results showed consistent shifts in bacterial communities in response to pollution. More geographically distant sites had more dissimilar communities (r = -0.886, P < 0.001) in this strongly connected sediment ecosystem. A variance analysis based on partitioning by principal coordinates of neighbor matrices (PCNM) showed that spatial distance (dispersal limitation) contributed more to bacterial community variation (8.2%) than any other factor, although the environmental factors explained more variance when combined (11.2%). In addition, potential indicator taxa (primarily affiliated with Deltaproteobacteria and Gammaproteobacteria) were identified; these taxa characterized the pollution gradient. This study provides direct evidence that dispersal limitation exists in a strongly connected marine sediment ecosystem and that candidate indicator taxa can be applied to evaluate coastal pollution levels.

  12. Polycyclic aromatic hydrocarbons in the largest deepwater port of East China Sea: impact of port construction and operation.

    PubMed

    Li, Juan-Ying; Cui, Yu; Su, Lei; Chen, Yiqin; Jin, Ling

    2015-08-01

    PAHs were analyzed for samples of seawater, sediment, and oyster (Saccostrea cucullata) collected from Yangshan Port, East China between 2012 and 2013. Concentrations of ∑PAHs in seawater (180-7,700 ng/L) and oyster (1,100-29,000 ng/g dry weight (dw)) fell at the higher end of the global concentration range, while sediment concentrations (120-780 ng/g dw) were generally comparable to or lower than those reported elsewhere. PAHs in the particulate phase accounted for 85% (52-93%) of the total PAHs in seawater. Congener profile analysis revealed that PAHs in waters originate mainly from petrogenic sources, while high-temperature combustion processes are the predominant sources for sediment. ∑PAHs in oyster well correlated with ∑PAHs in the particulate phase, suggesting particle ingestion as an important pathway for bioaccumulation of PAHs. Cancer risk assessment of PAHs in oyster indicated high human health risks posed by these chemicals to the coastal population consuming this seafood.

  13. Factor contribution to fire occurrence, size, and burn probability in a subtropical coniferous forest in East China

    PubMed Central

    Guo, Zhixing; Li, Yijia

    2017-01-01

    The contribution of factors including fuel type, fire-weather conditions, topography and human activity to fire regime attributes (e.g. fire occurrence, size distribution and severity) has been intensively discussed. The relative importance of those factors in explaining the burn probability (BP), which is critical in terms of fire risk management, has been insufficiently addressed. Focusing on a subtropical coniferous forest with strong human disturbance in East China, our main objective was to evaluate and compare the relative importance of fuel composition, topography, and human activity for fire occurrence, size and BP. Local BP distribution was derived with stochastic fire simulation approach using detailed historical fire data (1990–2010) and forest-resource survey results, based on which our factor contribution analysis was carried out. Our results indicated that fuel composition had the greatest relative importance in explaining fire occurrence and size, but human activity explained most of the variance in BP. This implies that the influence of human activity is amplified through the process of overlapping repeated ignition and spreading events. This result emphasizes the status of strong human disturbance in local fire processes. It further confirms the need for a holistic perspective on factor contribution to fire likelihood, rather than focusing on individual fire regime attributes, for the purpose of fire risk management. PMID:28207837

  14. Compound-specific isotopes of fatty acids as indicators of trophic interactions in the East China Sea ecosystem

    NASA Astrophysics Data System (ADS)

    Wu, Ying; Wang, Na; Zhang, Jing; Wan, Ruijing; Dai, Fangqun; Jin, Xianshi

    2016-09-01

    The composition and compound-specific isotopes of fatty acids were studied within food webs in the East China Sea. Lipid-normalized stable carbon isotopes of total organic carbon had a good correlation with trophic level. Variations in fatty acid compositions among diff erent species were observed but were unclear. Diff erent dietary structures could be traced from molecular isotopes of selected fatty acids in the Shiba shrimp ( Matapenaeus joyneri), the coastal mud shrimp ( Solenocera crassicornis) and the northern Maoxia shrimp ( Acetes chinensis). Both M. joyneri and S. crassicornis are mainly benthos feeders, while A. chinensis is a pelagic species, although they have a similar fatty acid composition. There was a good correlation for isotopes of arachidonic acid (C20:4n6; ARA) and docosahexaenoic acid (C22:6n3; DHA) among pelagic species from higher trophic levels. The isotopic compositions of DHA in benthic species were more negative than those of pelagic species at the same trophic level. The fact that the diet of benthic species contains more degraded items, the carbon isotopes of which are derived from a large biochemical fraction, may be the reason for this variation. A comparative study of benthic and pelagic species demonstrated the diff erent carbon sources in potential food items and the presence of a more complex system at the water-sediment interface.

  15. 129I and its species in the East China Sea: level, distribution, sources and tracing water masses exchange and movement

    PubMed Central

    Liu, Dan; Hou, Xiaolin; Du, Jinzhou; Zhang, Luyuan; Zhou, Weijian

    2016-01-01

    Anthropogenic 129I as a long-lived radioisotope of iodine has been considered as an ideal oceanographic tracer due to its high residence time and conservative property in the ocean. Surface water samples collected from the East China Sea (ECS) in August 2013 were analyzed for 129I, 127I and their inorganic chemical species in the first time. The measured 129I/127I ratio is 1–3 orders of magnitude higher than the pre-nuclear level, indicating its dominantly anthropogenic sources. Relatively high 129I levels were observed in the Yangtze River and its estuary, as well as in the southern Yellow Sea, and 129I level in seawater declines towards the ECS shelf. In the open sea, 129I and 127I in surface water exists mainly as iodate, while in Yangtze River estuary and some locations, iodide is dominated. The results indicate that the Fukushima nuclear accident has no detectable effects in the ECS until August 2013. The obtained results are used for investigation of interaction of various water masses and water circulation in the ECS, as well as the marine environment in this region. Meanwhile this work provides essential data for evaluation of the possible influence of the increasing NPPs along the coast of the ECS in the future. PMID:27849026

  16. Levels and distribution of hexabromocyclododecane (HBCD) in environmental samples near manufacturing facilities in Laizhou Bay area, East China.

    PubMed

    Li, Honghua; Zhang, Qinghua; Wang, Pu; Li, Yingming; Lv, Jianxia; Chen, Weihai; Geng, Dawei; Wang, Yawei; Wang, Thanh; Jiang, Guibin

    2012-10-26

    A total of 55 samples including soil, sediment, plants (cypress, reed and seepweed) and aquatic species were collected at locations around hexabromocyclododecane (HBCD) manufacturing facilities in Laizhou Bay area, East China. HBCD was determined at concentrations ranging between 0.88 and 6901 ng g(-1) dry weight (dw), 2.93-1029 ng g(-1) dw, 8.88-160241 ng g(-1) dw, and 7.09-815 ng g(-1) lipid weight (lw), respectively. Significant negative correlations (r(2) = 0.54, p = 0.006) were observed between HBCD concentrations in soils and the distance from the manufacturing facility, and the concentrations became constant when the distance was >4 km. The calculation results on the bioaccumulation factors (BAFs) suggested that HBCD may be accumulated in plants. Tissue-specific bioaccumulation of HBCD diastereoisomers was found in aquatic species. For example, in crabs the highest concentrations of HBCD (815 ng g(-1) lw for female and 446 ng g(-1) lw for male) were observed in the gill. Besides the gill, α-HBCD was more preferentially accumulated in the spermary and ovary, while β- and γ-HBCD were more accumulated in the muscle. A similar distribution was also observed in roe and muscle of goby fish.

  17. Ecotoxicological bioassays of sediment leachates in a river bed flanked by decommissioned pesticide plants in Nantong City, East China.

    PubMed

    Zhou, Yan; Wang, Fenghe; Wan, Jinzhong; He, Jian; Li, Qun; Qiang Chen; Gao, Jay; Lin, Yusuo; Zhang, Shengtian

    2017-03-01

    Traditionally, the toxicity of river contaminants is analyzed chemically or physically through river bed sediments. The biotoxicity of polluted sediment leachates has not caught our attention. This study aims to overcome this deficiency through a battery of biotests which were conducted to monitor comprehensive toxicity of sediment leachates for the Yaogang River in East Jiangsu Province of China, which is in close proximity to former pesticide plants. The general physical and chemical parameters of major pollutants were analyzed from river bed sediments collected at five strategic locations. The ecotoxicity analyses undertaken include overall fish (adult zebrafish) acute toxicity, luminescent bacteria (Vibrio fischeri) bioassay, and zebrafish embryo toxicity assay. Compared with the control group, sediment leachates increased the lethality, inhibited the embryos hatching and induced development abnormalities of zebrafish embryos, and inhibited the luminescence of V. fischeri. The results show that sediment leachates may assume various toxic effects, depending on the test organism. This diverse toxicity to aquatic organisms reflects their different sensitivity to sediment leachates. It is found clearly that V. fischeri was the organism which was characterized by the highest sensitivity to the sediment leachates. The complicated toxicity of leachates was not caused by one single factor but by multiple pollutants together. This indicates the need of estimations of sediment leachate not only taking into account chemical detection but also of applying the biotests to the problem. Thus, multigroup bioassays are necessary to realistically evaluate river ecological risks imposed by leachates.

  18. Application of a sea surface temperature front composite algorithm in the Bohai, Yellow, and East China Seas

    NASA Astrophysics Data System (ADS)

    Ping, Bo; Su, Fenzhen; Meng, Yunshan; Du, Yunyan; Fang, Shenghui

    2016-05-01

    The oceanic front is a narrow zone in which water properties change abruptly within a short distance. The sea surface temperature (SST) front is an important type of oceanic front, which plays a signifi cant role in many fi elds including fi sheries, the military, and industry. Satellite-derived SST images have been used widely for front detection, although these data are susceptible to infl uence by many objective factors such as clouds, which can cause missing data and a reduction in front detection accuracy. However, front detection in a single SST image cannot fully refl ect its temporal variability and therefore, the long-term mean frequency of occurrence of SST fronts and their gradients are often used to analyze the variations of fronts over time. In this paper, an SST front composite algorithm is proposed that exploits the frontal average gradient and frequency more eff ectively. Through experiments based on MODIS Terra and Aqua data, we verifi ed that fronts could be distinguished better by using the proposed algorithm. Additionally through its use, we analyzed the monthly variations of fronts in the Bohai, Yellow, and East China Seas, based on Terra data from 2000 to 2013.

  19. The Distribution of 18 Enterotoxin and Enterotoxin-Like Genes in Staphylococcus aureus Strains from Different Sources in East China.

    PubMed

    Cheng, Jinghua; Wang, Yan; Cao, Yongzhong; Yan, Wenguang; Niu, Xiaosai; Zhou, Liping; Chen, Jianhao; Sun, Ying; Li, Chenxi; Zhang, Xiaorong; Wu, Yantao

    2016-04-01

    The distribution of 18 staphylococcal enterotoxin (SE) or SE-like (SEl) genes in Staphylococcus aureus strains from different sources in east China was investigated. Among all 496 S. aureus strains, 291 strains carried one or more SE genes. The more frequently occurred genes were sea, seb, seg, selk, sell, selm, selo, and seq; the less frequent occurred genes were sec, selj, and ser. The classic SE genes and the enterotoxin gene cluster (egc) (seg, sei, selm, seln, selo, and/or selu) accounted for 25.67% and 61.68% of all detected genes, respectively. There were three gene clusters (egc, sea-sek-seq, and sed-sej-ser), of which the egc cluster was the important one that could generate novel complexes, and the sea-sek-seq cluster was a close relative to the hospital-acquired methicillin-resistant S. aureus. The SE gene distributions were different among strains of different sources and formed diverse toxin gene profiles. The human- and foodborne-origin strains harbored classic and novel SE and SEl genes, whereas animal-origin strains harbored egc and other novel SE and SEl genes mainly. The foodborne- and human-origin strains were the main dangerous factors of classic staphylococcal foodborne poisoning, whereas the strains (especially from animals) that carried egc and other novel genes mainly should be new potential dangerous factors for food safety.

  20. 129I and its species in the East China Sea: level, distribution, sources and tracing water masses exchange and movement

    NASA Astrophysics Data System (ADS)

    Liu, Dan; Hou, Xiaolin; Du, Jinzhou; Zhang, Luyuan; Zhou, Weijian

    2016-11-01

    Anthropogenic 129I as a long-lived radioisotope of iodine has been considered as an ideal oceanographic tracer due to its high residence time and conservative property in the ocean. Surface water samples collected from the East China Sea (ECS) in August 2013 were analyzed for 129I, 127I and their inorganic chemical species in the first time. The measured 129I/127I ratio is 1–3 orders of magnitude higher than the pre-nuclear level, indicating its dominantly anthropogenic sources. Relatively high 129I levels were observed in the Yangtze River and its estuary, as well as in the southern Yellow Sea, and 129I level in seawater declines towards the ECS shelf. In the open sea, 129I and 127I in surface water exists mainly as iodate, while in Yangtze River estuary and some locations, iodide is dominated. The results indicate that the Fukushima nuclear accident has no detectable effects in the ECS until August 2013. The obtained results are used for investigation of interaction of various water masses and water circulation in the ECS, as well as the marine environment in this region. Meanwhile this work provides essential data for evaluation of the possible influence of the increasing NPPs along the coast of the ECS in the future.

  1. Distribution and preservation of black carbon in the East China Sea sediments: Perspectives on carbon cycling at continental margins

    NASA Astrophysics Data System (ADS)

    Huang, Liang; Zhang, Jing; Wu, Ying; Wang, Jinlong

    2016-02-01

    We determined the concentrations and radiocarbon (14C) compositions of black carbon (BC) in the sediments of the East China Sea (ECS). The BC concentrations, which were in the range of 0.30-1.52 mg/g, accounted for 12-65% of the total organic carbon (TOC). The distribution of BC in ECS sediments was controlled by factors such as grain size, distance from the coast, and deposition rate. Radiocarbon measurements of BC yielded ages of 6350-10,440 years before present (BP), suggesting that the percentage of BC derived from biomass combustion was in the range of 29-48%. The BC burial flux in sediments of the ECS was estimated to be ∼1.39×106 t/yr, which was similar to burial fluxes reported for shelf sediments in other areas. However, the magnitude of the total BC sink was far greater than that of any other shelf regions studied to date, indicating the global importance of BC accumulation in the ECS, and the magnitude of BC input from large rivers (e.g., the Changjiang). The riverine delivery of BC to the ECS (73%) was far greater than that of atmospheric flux (27%). Further study of the BC cycle and the interactions of BC with other organic compounds in marginal seas was required to better understand the role of BC in the global carbon cycle.

  2. The origin of Cenozoic continental basalts in east-central China: Constrained by linking Pb isotopes to other geochemical variables

    NASA Astrophysics Data System (ADS)

    Xu, Zheng; Zheng, Yong-Fei; Zhao, Zi-Fu

    2017-01-01

    Cenozoic continental basalts in east-central China are characterized by OIB-like trace element patterns with more depleted to less enriched Sr-Nd isotope compositions. Such geochemical signatures are attributable to variable contributions to their mantle sources from crustal components in the oceanic subduction zone. A combined study of basalt Pb isotope variations with other geochemical variables indicates that four mantle and crustal components were involved in the basalt petrogenesis. Model calculations verify the geochemical transfer from the subducted crustal components to the mantle sources. The depleted MORB mantle component is indicated by the depleted Sr-Nd isotope compositions of basalts. Relatively high 206Pb/204Pb and low Δ8/4 ratios are ascribed to contributions from the igneous oceanic crust with high U/Pb and low Th/U ratios, low 206Pb/204Pb and high Δ8/4 ratios are ascribed to the lower continental crust, and high 206Pb/204Pb and high Δ8/4 ratios are linked to the seafloor sediment. This generates different compositions of mantle sources for these OIB-like continental basalts. The basalts with the most depleted Sr-Nd isotope compositions show Pb isotope compositions distinct from Pacific MORB but similar to Indian MORB, suggesting the occurrence of Indian type asthenospheric mantle beneath the continental lithosphere of eastern China. The depleted MORB mantle would be metasomatized by the three crustal components at the slab-mantle interface in oceanic subduction channel, generating the mantle sources that are enriched in melt-mobile incompatible trace elements and their pertinent radiogenic isotopes. Nevertheless, the crustal components were not directly incorporated in the forms of crustal rocks into the mantle sources, but underwent partial melting to produce the felsic melts that predominate the composition of those trace elements and their pertinent radiogenic isotopes in the basalts. As such, the depleted MORB mantle component was

  3. Ontogenetic changes in isotopic signatures of an omnivorous fish Cultrichthys erythropterus in East Lake Taihu, China

    NASA Astrophysics Data System (ADS)

    Li, Yunkai; Zhang, Miao

    2015-05-01

    The relationship between body size and stable isotopic signatures of the omnivorous Redfin Culter ( Cultrichthys erythropterus), commonly found in East Lake Taihu, was investigated. Previous analyses of C. erythropterus stomach contents have shown that this species undergoes a diet switch from being predominantly zooplanktivorous to piscivorous during its life history. This was confirmed by stable carbon isotopic signature (δ13C) in this study, in which δ13C was positively correlated with both standard length and weight. The importance of littoral-benthic resources in supporting C. erythropterus during its lifespan was also demonstrated using a two-source mixing model, the results of which showed a significant increasing trend in the contribution of littoral-benthic energy. However, the stable nitrogen isotopic signature (δ15N) exhibited an unusual pattern compared with previous studies. The δ15N of C. erythropterus showed no relationship with body size, even though dietary changes were observed. This indicated that δ15N alone cannot fully reflect a diet shift in a species and possible variability in isotopic signatures over its life history. This should be considered when using stable isotopic signatures to investigate intra-specific variations and the timing of life-history events, such as estimating the trophic positions of fish species.

  4. A strong ‘filter’ effect of the East China Sea land bridge for East Asia’s temperate plant species: inferences from molecular phylogeography and ecological niche modelling of Platycrater arguta (Hydrangeaceae)

    PubMed Central

    2014-01-01

    Background In East Asia, an increasing number of studies on temperate forest tree species find evidence for migration and gene exchange across the East China Sea (ECS) land bridge up until the last glacial maximum (LGM). However, it is less clear when and how lineages diverged in this region, whether in full isolation or in the face of post-divergence gene flow. Here, we investigate the effects of Quaternary changes in climate and sea level on the evolutionary and demographic history of Platycrater arguta, a rare temperate understorey shrub with disjunct distributions in East China (var. sinensis) and South Japan (var. arguta). Molecular data were obtained from 14 P. arguta populations to infer current patterns of molecular structure and diversity in relation to past (Last Interglacial and Last Glacial Maximum) and present distributions based on ecological niche modelling (ENM). A coalescent-based isolation-with-migration (IM) model was used to estimate lineage divergence times and population demographic parameters. Results Combining information from nuclear/chloroplast sequence data with nuclear microsatellites, our IM analyses identify the two varieties as genetically distinct units that evolved in strict allopatry since the mid-Pleistocene, c. 0.89 (0.51–1.2) Ma. Together with Bayesian Skyeline Plots, our data further suggest that both lineages experienced post-divergence demographic growth, followed by refugial isolation, divergence, and in the case of var. arguta post-glacial admixture. However, past species distribution modelling indicates that the species’ overall distribution has not greatly changed over the last glacial cycles. Conclusions Our findings highlight the important influence of ancient sea-level changes on the diversification of East Asia’s temperate flora. Implicitly, they challenge the notion of general temperate forest expansion across the ECS land bridge, demonstrating instead its ‘filter’ effect owing to an unsuitable environment

  5. Correlation of surface sensible heat flux in the arid region of northwestern China with the northern boundary of the East Asian summer monsoon and Chinese summer precipitation

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Li, Dongliang

    2011-10-01

    Northwestern (NW) China is the typical arid region of central Asia, and its surface sensible heat (SSH) anomaly significantly affects the Chinese climate and the atmospheric circulation of East Asia. In this study, we investigated the relationship between the SSH flux in the NW arid region of China and the northern boundary of the East Asian summer monsoon (EASM) and Chinese summer rainfall using a climatic diagnosis analysis method. Then the causes of formation were analyzed from the changes of the transfer of water vapor, geopotential height field, and the upper- and lower-level atmospheric circulation fields, and so on. It is found that during years of unusually weak (strong) SSH flux, the northern boundary of the EASM shifts northward (southward) than in normal years. There is an interplay between the SSH in the NW arid region of China and the precipitation in the northern boundary zone of the EASM: In the early stage of the monsoon, the SSH inhibits the latter precipitation, and during the peak of the monsoon, the precipitation suppresses the SSH. The teleconnection wave train structure of the geopotential height field at 500 hPa and the upper- lower-level atmospheric circulation fields above the Eurasian continent exhibit profound changes when summer SSH fluxes are unusually weak and strong. These changes are accompanied by significant alterations to the vertical velocity field and the water vapor field above northern China. The combination of these changes thereby contributes to the unusually southward shift of the northern boundary of the EASM.

  6. Risk factors for sporadic Vibrio parahaemolyticus gastroenteritis in east China: a matched case-control study.

    PubMed

    Yan, W X; Dai, Y; Zhou, Y J; Liu, H; Duan, S G; Han, H H; Chen, Y

    2015-04-01

    SUMMARY To determine risk factors for sporadic Vibrio parahaemolyticus gastroenteritis, we conducted a population-based case-control study in sentinel hospital surveillance areas of Shanghai and Jiangsu province, China. Seventy-one patients with diarrhoea and confirmed V. parahaemolyticus infections were enrolled, and they were matched with 142 controls for gender, age and residential area. From the multivariable analysis, V. parahaemolyticus infections were associated with antibiotics taken during the 4 weeks prior to illness [odds ratio (OR) 7·6, 95% confidence interval (CI) 1·1–54·4)], frequent eating out (OR 3·3, 95% CI 1·0–10·4), and shellfish consumption (OR 3·4, 95% CI 1·0–11·1), with population-attributable fractions of 0·09, 0·24, and 0·14, respectively. Protective factors included keeping the aquatic products refrigerated (OR 0·4, 95% CI 0·2–1·0) and pork consumption (OR 0·2, 95% CI 0·1–0·9) [corrected] .

  7. Type 1 Retinopathy of Prematurity and Its Laser Treatment of Large Preterm Infants in East China

    PubMed Central

    Shan, Haidong; Ni, Yinqing; Xue, Kang; Yu, Jia; Huang, Xin

    2015-01-01

    Purpose To describe Type 1 retinopathy of prematurity (ROP) and its laser treatment outcomes in premature infants with birth weight > 1250 g in Eastern China. Methods A retrospective review of 3175 ROP records was conducted at Shanghai Eye & ENT Hospital of Fudan University. The records were collected at the ROP clinic from 2006 to 2014, including their demographic and medical information such as gestational age, birth weight, supplemental oxygen therapy, systemic complications, ROP stage, location, presence of plus disease. All infants were examined by RetCam fundus camera. Those with Type 1 ROP were also examined by indirect ophthalmoscope before undergoing transpupillary laser treatment. Results A total of 12 infants (24 eyes) with Type 1 ROP and birth weight > 1250 g were enrolled. All infants enrolled had plus disease and ROP in zone II retina. Specifically, 16 eyes (67%) had stage 2 ROP. 8 eyes (33%) had stage 3 ROP. ROP regressed in 23 eyes (96%) following laser treatment. Partial retinal detachment developed in one eye (4%). No severe involution sequelaes or laser-related complications were recorded. Mean follow-up was 30±6 weeks. Conclusion Type 1 ROP may occur in large premature infants who have undergone supplemental oxygen therapy. This Type 1 ROP is mainly located in zone II retina. Laser treatment is a safe and effective intervention for these infants. PMID:26674190

  8. Land-sea interactions at the east coast of Hainan Island, South China Sea: A synthesis

    NASA Astrophysics Data System (ADS)

    Zhang, Jing; Wang, Dao Ru; Jennerjahn, Tim; Dsikowitzky, Larissa

    2013-04-01

    The structure and function of coastal ecosystems is affected by land-based human activities, including changes in water, sediment and pollutant input, as well as land reclamation in coastal areas. Many coastal areas can be considered over-stressed systems as a whole, the ecosystem services of which are strongly impaired. This is particularly important in tropical regions, where the coastal zone is under the influence of a strong climate variability including monsoons and frequent extreme weather events, such as typhoons. During the past decades the continuous development of Hainan's coastal zone and its hinterland, in combination with episodic natural events (e.g., typhoons), caused environmental changes in its coastal ecosystems. However, little is known on the consequences of environmental changes for the biogeochemistry and ecology and, hence, the natural resources of the Hainan coastal ecosystems. The Sino-German inter-disciplinary LANCET (land-sea interactions along coastal ecosystems of tropical China: Hainan) project was designed to address these issues on a local to regional scale and at the same time, to contribute to the global data base in which this type of information from tropical regions is still under-represented. The results obtained from LANCET have been delivered to the local government for an adaptive management at the ecosystem level, and the knowledge is believed to be relevant to other studies of tropical and coastal regions.

  9. JPRS Report, East Europe.

    DTIC Science & Technology

    2007-11-02

    rent news and information and is published Monday through Friday in 8 volumes: China, East Europe, Soviet Union, East Asia, Near East & South Asia...JPRS-EER-87-141 23 SEPTFMRFR 1QS7 u etc* U ü J. Ma M i%\\ ■■■■■« FOREIGN BROADCAST INFORMATION SERVICE JPRS Report— East Eur ft e N9BQ6W M...EER-87-141 23 SEPTEMBER 1987 EAST EUROPE CONTENTS POLITICAL INTRABLOC Romanian Efforts To Weaken Minority Magyar Position Viewed (Martti Valkonen

  10. Seasonal variability of nutrients in the Yangtze Estuary and adjacent waters: A model study

    NASA Astrophysics Data System (ADS)

    Zong, H.; Ding, P.

    2014-12-01

    Eutrophication has been one of the major threats to the coastal ecosystem. Several factors are believed to be associated with eutrophication, which including the high nutrient loads delivered into the estuary from river. Yangtze river is the longest river in China. It brings huge amount of nutrients into the Yangtze Estuary (YE) and adjacent East China Sea (ECS) and contributes significantly to the eutrophication in estuary and the adjacent waters. The eutrophication in this region exhibits strong seasonal variability, with the worst situation occurring in summer. This seasonal variability might be coupled with the timing of riverine nutrient inputs and physical processes (wind and along-shore current). To study seasonal variability of nutrients (N/P) in YE, a 3D physical-biological coupled model was applied to the YE and its adjacent waters. The physical model was the Regional Ocean Model System (ROMS) and the biological model was a nitrogen, phytoplankton, zooplankton, and detritus (NPZD) model. The simulated nutrients distribution pattern was consistent with observation. With the numerical experiments, we examined nutrients transport under different river loads and different physical processes. Seasonal variability of nutrients budget in YE and alone-shelf transport flux were also studied.

  11. Deep conductivity characteristics and preliminary acquaintance of the Lushan earthquake, east edge of Tibetan Plateau, China

    NASA Astrophysics Data System (ADS)

    Zhou, J.; Wang, X.; Wang, Y.; Min, G.

    2013-12-01

    resistive intermediate belt at the edge of western basin. Be different form Wenchuan earthquake, Lushan earthquake located in the south of Longmenshan tectonic zone which have a strong connection with the piedmont fault. MT research reveals the difference of the deep electrical structure between the south of Longmenshan tectonic belt and the middle-north belt, from which we can infer that the seismogenic environment are not the same. The epicenter of Lushan earthquake occurred in the east edge of Longmenshan tectonic belt which close to Longmenshan ';s piedmont fault combine with the MT inversion infer that Lushan earthquake has a stronger relationship with Longmenshan ';s piedmont fault. Because of the short term of our work, now further work is ongoing.

  12. Tracking Monsoon Related Provenance Changes in Continental Margin Sediments of the East China Sea: Preliminary Results from IODP Expedition 346.

    NASA Astrophysics Data System (ADS)

    Anderson, C. H.; Dunlea, A. G.; Murray, R. W.; Kinsley, C. W.; McGee, D.; Giosan, L.; Zheng, H.; Tada, R.; Alvarez Zarikian, C. A.

    2014-12-01

    Sedimentation in the East China Sea (ECS) is driven largely by fluvial and eolian fluxes that are likely influenced by the East Asian Monsoon (EAM). Terrigenous matter from the Yangtze River is transported into the ECS and is also carried by winds of the Westerly Jet. Seasonal and long term shifts in the atmospheric and precipitation regimes over Asia are recorded in the inorganic chemistry of the sediment of the ECS and other Asian coastal seas. For example, changes in intensity and timing of the EAM over short and long term time scales likely impact the relative proportion of fluvial and eolian inputs to the region, and perhaps their individual sources. Bulk sediment was recovered from IODP Sites U1428 and U1429 in the ECS during Expedition 346. T these sites are separated by 7.4 km, located in the northernmost portion of the ECS in the Danjo Basin, and are generally characterized by two sedimentary units. Unit A is largely nannofossil-rich calcareous ooze and calcareous-rich clays, punctuated with smaller tephra layers throughout. Unit B is composed of fine- to medium-grained, rounded sands. Here we present major, trace and rare earth element (REE) data for 54 bulk sediment samples analyzed via ICP-ES and ICP-MS. We trace downhole fluctuations in the geochemical data in order to investigate the provenance of terrigenous material during the Pleistocene. Preliminary major element concentration data indicate the presence of distinct continental sediment and carbonates at both sites. Average downhole major element ratios exhibit limited variation at both sites. For example, Ti/Al (g/g) is tightly constrained with values of 0.05 /- 0.003, Fe/Al 0.5 /- 0.05, and Si/Al 3.3 /- 0.3. In addition to standard geochemical techniques to assess provenance, we are using multivariate statistics (e.g., Q-Mode Factor Analyses, Multiple Linear Regressions) to examine this large dataset. We focus on a smaller suite of elements that are exclusively associated with the terrigenous

  13. Tree diversity promotes insect herbivory in subtropical forests of south-east China

    PubMed Central

    Schuldt, Andreas; Baruffol, Martin; Böhnke, Martin; Bruelheide, Helge; Härdtle, Werner; Lang, Anne C; Nadrowski, Karin; von Oheimb, Goddert; Voigt, Winfried; Zhou, Hongzhang; Assmann, Thorsten; Fridley, Jason

    2010-01-01

    1.Insect herbivory can strongly affect ecosystem processes, and its relationship with plant diversity is a central topic in biodiversity–functioning research. However, very little is known about this relationship from complex ecosystems dominated by long-lived individuals, such as forests, especially over gradients of high plant diversity. 2.We analysed insect herbivory on saplings of 10 tree and shrub species across 27 forest stands differing in age and tree species richness in an extraordinarily diverse subtropical forest ecosystem in China. We tested whether plant species richness significantly influences folivory in these highly diverse forests or whether other factors play a more important role at such high levels of phytodiversity. 3.Leaf damage was assessed on 58 297 leaves of 1284 saplings at the end of the rainy season in 2008, together with structural and abiotic stand characteristics. 4.Species-specific mean damage of leaf area ranged from 3% to 16%. Herbivory increased with plant species richness even after accounting for potentially confounding effects of stand characteristics, of which stand age-related aspects most clearly covaried with herbivory. Intraspecific density dependence or other abiotic factors did not significantly influence overall herbivory across forest stands. 5.Synthesis.The positive herbivory–plant diversity relationship indicates that effects related to hypotheses of resource concentration, according to which a reduction in damage by specialized herbivores might be expected as host plant concentration decreases with increasing plant diversity, do not seem to be major determinants for overall herbivory levels in our phytodiverse subtropical forest ecosystem. We discuss the potential role of host specificity of dominant herbivores, which are often expected to show a high degree of specialization in many (sub)tropical forests. In the forest system we studied, a much higher impact of polyphagous species than traditionally assumed

  14. Acidifying intermediate water accelerates the acidification of seawater on shelves: An example of the East China Sea

    NASA Astrophysics Data System (ADS)

    Lui, Hon-Kit; Chen, Chen-Tung Arthur; Lee, Jay; Wang, Shu-Lun; Gong, Gwo-Ching; Bai, Yan; He, Xianqiang

    2015-12-01

    This study is the first to present observed acidification rates at the shelf break of the East China Sea (ECS) and in the Okinawa Trough between 1982 and 2007. The use of apparent oxygen utilization (AOU) data to quantify the change in pH due to physical changes and changes in biological activities is demonstrated. The results thus obtained reveal that the drop in pH of the Kuroshio Intermediate Water (KIW) in the ECS is a result of not only the intrusion of atmospheric CO2, but also an increase in AOU concentration. The acidification rates caused by the increasing AOU concentration could contribute up to -0.00086±0.00017 pH unit yr-1 at 900 m in the Okinawa Trough and -0.00082±0.00057 pH unit yr-1 on the shelf break of the ECS. These values are equivalent to 54% and 51%, respectively, of the acidification rate of -0.0016 pH unit yr-1 based on an assumption of the air-sea CO2 equilibrium. When the effects of changing AOU and θ are eliminated, the acidification rate in the basin of the ECS captures the rate of change that is caused by an increase in anthropogenic CO2 concentration. In contrast, when the effects of changing AOU and θ are eliminated, the acidification rate at the shelf break is 69% higher than the rate based on an assumption of the air-sea CO2 equilibrium. Since the seawater on the shelf contains a higher proportion of the South China Sea (SCS) seawater and coastal water than does that in the Okinawa Trough, the result herein may imply that the SCS seawater, coastal water, or a combination of them suffered a higher acidification rate during the studied period. This study, to the best of the authors' knowledge, is the first to demonstrate that changing the carbonate chemistry of both incoming offshore intermediate seawater and coastal water results in the acidification of seawater on a continental shelf. The results herein reveal a situation in which the acidification of coastal seawater may be faster than expected when the reduction of pH of the

  15. Chemical composition and mass size distribution of PM1.0 at an elevated site in central east China

    NASA Astrophysics Data System (ADS)

    Zhang, Y. M.; Zhang, X. Y.; Sun, J. Y.; Hu, G. Y.; Shen, X. J.; Wang, Y. Q.; Wang, T. T.; Wang, D. Z.; Zhao, Y.

    2014-06-01

    Size-resolved aerosol chemical compositions were measured continuously for one and half years with an aerosol mass spectrometer (AMS) to characterize the mass and size distributions (MSDs) of each component in bulk, fresh and aged submicron particles (approximately PM1.0) at Mountain Tai, an elevated site in Central East China (CEC) from June 2010 to January 2012. The majority of the regionally-dispersed aerosols were found to be contributed from short distance mixed aerosol, mostly from its south with organics and sulfate as the major components. The annual mean mass concentrations of organics, sulfate, nitrate, ammonium and chloride were 11.2, 9.2, 7.2, 5.8 and 0.95 μg m-3, respectively, which are much lower for organics and sulfate, and slightly lower for nitrate, ammonium and chloride than those at the nearby surface rural sites. High organics were observed for all four seasons, and the relatively fresh organic aerosol (OA) containing high proportion of less-photo chemically OA, were found from long-range transported aerosol from northwest. Semi-volatile and low-volatile oxidized OAs together contributed approximately 49%, 55% in spring and 72% and 51% in winter of total OA, showing at least 50% of OA can be attributable to SOA. Seasonally, the chemical components at the elevated site showed a "winter high and autumn low" pattern, with organics, sulfate and ammonium peaking in summer. Though no obvious differences of MSDs were seen for various chemical components in the planetary boundary layer (PBL) and free troposphere (FT), the concentrations were a factor of 5-7 higher in PBL than in FT. The averaged MSDs of particles between 30-1000 nm for organics, sulfate, nitrate, and ammonium are approximately log-normal with similar mass median diameters (MMDs) of 539, 585, 542, and 545 nm, respectively, which were slightly larger than those in ground sites within North China Plain (NCP). Obvious differences in MMDs were found between fresh and aged aerosols for

  16. Temporal evolution of granitic magmas in the Luanchuan metallogenic belt, east Qinling Orogen, central China: Implications for Mo metallogenesis

    NASA Astrophysics Data System (ADS)

    Li, Dong; Han, Jiangwei; Zhang, Shouting; Yan, Changhai; Cao, Huawen; Song, Yaowu

    2015-11-01

    The Luanchuan metallogenic belt, located within the eastern part of the Qinling Orogen, central China, hosts a number of world-class Mo deposits that are closely related to small late Mesozoic granitic plutons. Zircon U-Pb dating of distinct plutons in the Luanchuan metallogenic belt has yielded ages of 153 ± 1, 154 ± 2, 152 ± 2, and 148 ± 1 Ma. Molybdenite Re-Os isotopic compositions of Yuku ore district in the southern part of Luanchuan metallogenic belt has yielded an isochron age of 146 ± 1 Ma, which is consistent with the large-scale mineralization ages in the northern part of the Luanchuan metallogenic belt. A combination of previous studies and new geochronological and isotopic data show a concordant temporal and genetic link between granitic magmatism and Mo mineralization in the Luanchuan metallogenic belt, suggesting that this mineralization episode formed the most extensive Mo mineralization belt in the east Qinling Orogen. Zircon grains from Mo-related granitic plutons show similar trace element distributions. High-precision Multi Collector-Inductively Coupled Plasma-Mass Spectrometry (MC-ICP-MS) Pb isotope analysis of K-feldspar megacrysts from mineralization-related granites suggest that they were derived from the lower crust. Similarly, the Pb isotopic compositions of pyrite coprecipitated with molybdenite also suggest that the metals were derived form the lower crust, with probably minor mantle contribution. A continuum mineralization model that describes the sourcing of Mo from an evolving granitic magma over successive differentiation events, possibly in separate but connected magma chambers, could explain the remarkable Mo enrichment in the Luanchuan metallogenic belt. The volatile- and Mo-bearing granitic magmas ascended as diapirs from the deep crust, and were emplaced as dikes in the upper crust. Lithological differences between these Mo-bearing granites may relate to different stages in the evolution of individual magmas. Finally, ore

  17. Enhancement of Eddy Heat Transport due to the Anticyclonic Submesoscale Eddies around Ryukyu Islands near Kuroshio in East China Sea

    NASA Astrophysics Data System (ADS)

    Kamidaira, Y.; Uchiyama, Y.; Mitarai, S.; Miyazawa, Y.

    2014-12-01

    A synoptic, regional downscaling experiment of Kuroshio off Ryukyu Islands, Japan, exhibits the evident predominance of submesoscale anticyclonic eddies over cyclones in the narrow strip between Kuroshio and the islands (Uchiyama et al., 2013). In the present study, the mechanism and impacts of the anticyclone dominance are examined with a detailed oceanic downscaling model in a double nested ROMS configuration at the horizontal resolution of 3km (ROMS-L1) and 1km (ROMS-L2), forced by the assimilative JCOPE2 oceanic reanalysis and the JMA GPV-MSM atmospheric hindcast. The model results are extensively validated against a variety of data including shipboard hydrography and satellite altimetry and temperature data to show a good agreement. An alternative ROMS-L2 experiment is also conducted to examine topographic effects on the anticyclones around the Ryukyu Islands by eliminating all the island topography above z > -1000 m, while the other configurations are held unchanged. If the islands are removed, the submesoscale negative vortices on the eastern side of the Kuroshio become much weaker than those of the original case with the islands. The experiment clearly demonstrates that dominance of the negative vorticity between Kuroshio and the Ryukyu Islands is caused by enhanced lateral shear due to the concentrated Kuroshio mean current associated with appropriate formation of the eastern branch, the northward-drifting Ryuku Current, and resultant eddy shedding in the narrow channel between the continental shelf of the East China Sea and the Okinawan ridge. A diagnostic eddy heat flux analysis illustrates that the submesoscale anticyclonic eddies play a crucial role in enhancing the eddy heat transport and thus the lateral mixing between Kuroshio and the islands as compared to those in the coarser resolution models (L1 and JCOPE2), resulting in promoting regional larval and material transport from Kuroshio to the islands.

  18. Role of mariculture in the loading and speciation of mercury at the coast of the East China Sea.

    PubMed

    Liang, Peng; Gao, Xuefei; You, Qiongzhi; Zhang, Jin; Cao, Yucheng; Zhang, Chan; Wong, Ming-Hung; Wu, Sheng-Chun

    2016-11-01

    The effects of mariculture on mercury (Hg) contamination and speciation in water, sediment and cultured fish in a typical mariculture zone located in Xiangshan bay, Zhejiang province, east China, were studied. Water, sediment and fish samples were collected from mariculture sites (MS) and from corresponding reference sites (RS) 2500 m away from the MS. The THg concentration in overlying water in Xiangshan bay reached as high as 16.6 ± 19.5 ng L(-1), indicating that anthropogenic sources in this bay may contribution on Hg contamination in overlying water. Mariculture activities resulted in an increase in THg concentration in water from surface and bottom layers, which may be attributed to the discharge of domestic sewage and the accumulation of unconsumed fish feed and fish excreta in the benthic environment. Methylmercury (MeHg) concentrations in the bottom layer of overlying water and top surface layer of porewater underneath MS were higher than at RS, implying that mariculture activities promote Hg methylation in the interface between sediments and water. In addition, the concentrations of MeHg in sediment and porewater were significantly higher in summer than winter. It was observed that THg and MeHg contents in the muscle of blackhead seabream (Acanthopagrus schlegelii) (fed by the trash fish) were significantly higher (p < 0.001) than those in red snapper (Lutjanus campechanus) or perch (Perca fluviatilis) (fed by pellet fish feed). The THg and MeHg concentrations in the fish meat were closely related to the feeding mode, which indicate that fish feed rather than environmental media is the major pathway for Hg accumulation in fish muscle.

  19. Subsurface lacustrine storm-seiche depositional model in the Eocene Lijin Sag of the Bohai Bay Basin, East China

    NASA Astrophysics Data System (ADS)

    Wang, Junhui; Jiang, Zaixing; Zhang, Yuanfu

    2015-10-01

    Recent progress in facies analysis helps to discriminate storm-induced deposits based on interpretation of sedimentary records of combination of oscillatory and unidirectional flows. Located in the southeastern corner of the Bohai Bay Basin in East China, the Lijin Sag is a NE-SW trending Cenozoic half-graben basin. Part of its Eocene deposits (Bindong deposits), which are deposited far away from a contemporary shoreline, consists of thin bedded fine-sandstones and siltstones, interlayed with dark-gray mudstones. New data from drilling wells permit an interpretation of the sedimentary facies. Based on seismic data, well log data, core data and thin-section analyses, storm-dominated deposits were recognized. Petrologic analysis shows that these deposits mainly consist of fine sand- to silt-sized lithic arkose. Detailed sedimentological analyses on lithofacies were conducted to address flowtypes dominant during their geneses. The beds are normal graded and contain Bouma-like sequences. The typical and complete sedimentary sequence consists of fining-upwards successions from an erosive base, followed by gravity flow-induced massive or faint laminated bed or soft sediment deformation structures and unidirectional-combined-oscillatory flow induced beddings, which are attributed to storm wave and seiche processes. From proximal to distal in plane, the Bindong storm deposits exhibit different lithofacies associations and sedimentary processes, i.e., the proximal facies is coarser and dominated by gravity flows, unidirectional flows and combined flows, and formed under strong hydrodynamic conditions; the transitional facies is formed under full range of flow regimes exhibiting a complete Bouma-like sequence; while the distal facies is dominated by gravity flows and pure unidirectional flows without influence of waves. During the deposition period of the Bindong deposits, the paleo-environmental characteristics, such as paleogeographic position, paleoclimate, provenance

  20. A unique Fe-rich carbonate chimney associated with cold seeps in the Northern Okinawa Trough, East China Sea

    NASA Astrophysics Data System (ADS)

    Sun, Zhilei; Wei, Helong; Zhang, Xunhua; Shang, Luning; Yin, Xijie; Sun, Yunbao; Xu, Lei; Huang, Wei; Zhang, Xianrong

    2015-01-01

    The East China Sea is an important marginal sea of the Western Pacific Ocean, from which natural gas hydrate sample has not been acquired so far. Recently, copious carbonate chimneys have been discovered in turbidite deposits in the olistostrome zone located on the west slope of the northern section of Okinawa Trough. Here, the petrology, geochemistry and chronology of an iron-rich carbonate chimney were characterized, confirming a close relationship between its formation and the dissociation of natural gas hydrate beneath the chimney in OT. A distinctive relationship has been observed between goethite and total carbonate contents along with a negative correlation between Fe and Ca contents. Conversely, abundant Fe accumulated on carbonate substrate by mineralized microorganisms. The δ13C values of the chimney wall were from -27.56 to -43.66‰ (average: -37.18‰, V-PDB), implying anaerobic oxidation of methane (AOM) as a predominant controlling factor on carbonate precipitation. As no pyrite and organic residues were identified in the iron-rich chimney, it was assumed that AOM was coupled to the iron reduction reaction at least to some extent during the chimney growth owing to the local deficiency of sulfate supply. The δ56Fe values of bulk chimney wall (ranging from -0.316‰ to -0.023‰, average -0.134‰) suggest mass and isotope exchanges between the chimney and ambient environment during its growth history, whereas the enrichment of δ18O of the carbonate implies these carbonate sourcing from hydrate dissociation underlying our sampling site. This assumption has been supported by a distinct bottom simulation reflector (BSR) and a well-developed fault system beneath the sampling site. This is the first report of cold seepage inside the OT and the identified iron-dependent AOM has shed a new light to the Carbon cycle related to the marine methane oxidation, particularly before the Great Oxidation Event ~2.45 Ga ago.

  1. The influence of Asian dust outflow on particle microphysical and optical properties at Mt. Tai in central east China

    NASA Astrophysics Data System (ADS)

    Shen, X. J.; Sun, J. Y.; Zhang, Y. M.; Zhang, X. Y.; Wang, T. T.; Wang, Y. Q.; Zhang, L.; Fan, R. X.; Zhao, Y.; Wang, D. Z.

    2016-10-01

    An in-situ measurement of the particle number size distribution and optical properties (scattering and absorption coefficients) of PM2.5 was conducted at Mt. Tai, a mountain top station in central east China in the spring of 2011. It was found that the particle size distribution, mass concentration, as well as the optical properties have been modified during the dust periods. The mean mass concentration of PM2.5 during the dust periods was nearly twice of that during the non-dust period. The number and volume size distribution showed a higher concentration in the size range of 0.5-2.5 μm during the dust period, which were identified as dust particles. The absorption coefficient increased by ∼40%, while the scattering coefficient did not show much difference. The single scattering albedo of 0.85 during dust period was also comparable with the value of 0.89 during non-dust period. The Mie model was applied to simulate the aerosol optical properties and validated through a closure study for an intensive dust event. This study quantitatively demonstrated that dust particles contributed to nearly 63% of the scattering coefficient, while the remainder was mainly due to anthropogenic particles on dust days. The dust particles took a lower portion to the absorption, about 40%, indicating the anthropogenic particles still played a more dominant role in absorbing. This study also indicated that although there were only a few tens of dust particles during dust period, they could influence in particle optical properties significantly.

  2. Niche partitioning of marine group I Crenarchaeota in the euphotic and upper mesopelagic zones of the East China Sea.

    PubMed

    Hu, Anyi; Jiao, Nianzhi; Zhang, Rui; Yang, Zao

    2011-11-01

    Marine group I Crenarchaeota (MGI) represents a ubiquitous and numerically predominant microbial population in marine environments. An understanding of the spatial dynamics of MGI and its controlling mechanisms is essential for an understanding of the role of MGI in energy and element cycling in the ocean. In the present study, we investigated the diversity and abundance of MGI in the East China Sea (ECS) by analysis of crenarchaeal 16S rRNA gene, the ammonia monooxygenase gene amoA, and the biotin carboxylase gene accA. Quantitative PCR analyses revealed that these genes were higher in abundance in the mesopelagic than in the euphotic zone. In addition, the crenarchaeal amoA gene was positively correlated with the copy number of the MGI 16S rRNA gene, suggesting that most of the MGI in the ECS are nitrifiers. Furthermore, the ratios of crenarchaeal accA to amoA or to MGI 16S rRNA genes increased from the euphotic to the mesopelagic zone, suggesting that the role of MGI in carbon cycling may change from the epipelagic to the mesopelagic zones. Denaturing gradient gel electrophoretic profiling of the 16S rRNA genes revealed depth partitioning in MGI community structures. Clone libraries of the crenarchaeal amoA and accA genes showed both "shallow" and "deep" groups, and their relative abundances varied in the water column. Ecotype simulation analysis revealed that MGI in the upper ocean could diverge into special ecotypes associated with depth to adapt to the light gradient across the water column. Overall, our results showed niche partitioning of the MGI population and suggested a shift in their ecological functions between the euphotic and mesopelagic zones of the ECS.

  3. Comparison of buried sand ridges and regressive sand ridges on the outer shelf of the East China Sea

    NASA Astrophysics Data System (ADS)

    Wu, Ziyin; Jin, Xianglong; Zhou, Jieqiong; Zhao, Dineng; Shang, Jihong; Li, Shoujun; Cao, Zhenyi; Liang, Yuyang

    2016-07-01

    Based on multi-beam echo soundings and high-resolution single-channel seismic profiles, linear sand ridges in U14 and U2 on the East China Sea (ECS) shelf are identified and compared in detail. Linear sand ridges in U14 are buried sand ridges, which are 90 m below the seafloor. It is presumed that these buried sand ridges belong to the transgressive systems tract (TST) formed 320-200 ka ago and that their top interface is the maximal flooding surface (MFS). Linear sand ridges in U2 are regressive sand ridges. It is presumed that these buried sand ridges belong to the TST of the last glacial maximum (LGM) and that their top interface is the MFS of the LGM. Four sub-stage sand ridges of U2 are discerned from the high-resolution single-channel seismic profile and four strikes of regressive sand ridges are distinguished from the submarine topographic map based on the multi-beam echo soundings. These multi-stage and multi-strike linear sand ridges are the response of, and evidence for, the evolution of submarine topography with respect to sea-level fluctuations since the LGM. Although the difference in the age of formation between U14 and U2 is 200 ka and their sequences are 90 m apart, the general strikes of the sand ridges are similar. This indicates that the basic configuration of tidal waves on the ECS shelf has been stable for the last 200 ka. A basic evolutionary model of the strata of the ECS shelf is proposed, in which sea-level change is the controlling factor. During the sea-level change of about 100 ka, five to six strata are developed and the sand ridges develop in the TST. A similar story of the evolution of paleo-topography on the ECS shelf has been repeated during the last 300 ka.

  4. Distribution and cycling of carbon monoxide in the east china sea and the marine atmosphere in autumn

    NASA Astrophysics Data System (ADS)

    He, Zhen; Xu, Guanqiu; Yang, Guipeng

    2015-12-01

    Carbon monoxide (CO) concentrations, sea-to-air fluxes and microbial consumption rate constants, along with atmospheric CO mixing ratios, were measured in the East China Sea (ECS) in autumn. Atmospheric CO mixing ratios varied from 96 to 256 ppbv, with an average of 146 ppbv (SD = 54 ppbv, n = 31). Overall, the atmospheric CO concentrations displayed a decreasing trend from inshore to offshore stations. The surface water CO concentrations in the investigated area ranged from 0.24 to 6.12 nmol L-1, with an average of 1.68 nmol L-1 (SD = 1.50 nmol L-1, n = 31). The surface water CO concentrations were affected significantly by sunlight. Vertical profiles showed that CO concentrations declined rapidly with depth, with the maximum appearing in the surface water. The surface CO concentrations were oversaturated, with the saturation factors ranging from 1.4 to 56.9, suggesting that the ECS was a net source of atmospheric CO. The sea-to-air fluxes of CO in the ECS ranged from 0.06 to 11.31 µmol m-2 d-1, with an average of 2.90 µmol m-2 d-1 (SD = 2.95µmol m-2 d-1, n = 31). In the incubation experiments, CO concentrations decreased exponentially with incubation time and the processes conformed to the first order reaction characteristics. The microbial CO consumption rate constants in the surface water (KCO) ranged from 0.063 to 0.22 h-1, with an average of 0.12 h-1 (SD = 0.062 h-1, n = 6). A negative correlation between KCO and salinity was observed in the present study.

  5. Cross-shelf water exchange in the East China Sea as estimated by satellite altimetry and in situ hydrographic measurement

    NASA Astrophysics Data System (ADS)

    Ding, Ruibin; Huang, Daji; Xuan, Jiliang; Mayer, Bernhard; Zhou, Feng; Pohlmann, Thomas

    2016-09-01

    Combining satellite altimetry and in situ hydrographic measurement, we estimated the cross-shelf transport (CST) and its spatial and temporal variations across 200 m isobath in the East China Sea (ECS) from 1993 to 2014. The vertically integrated CST can be dynamically divided into three parts: surface Ekman transport, geostrophic transport, and bottom Ekman transport. The results show that the 22 year-mean, sectionally integrated CST to be 1.7 ± 2.0 Sv (positive in the on-shelf direction), comprised of bottom and surface Ekman transports of 2.7 ± 1.0 Sv and 0.6 ± 0.6 Sv, respectively, that are partially offset by a geostrophic transport of -1.5 ± 1.7 Sv. The sectionally integrated CST shows significantly high power at roughly annual period from 1999 to 2001, with lower power at intra-annual period. The vertically integrated CST to the northeast of Taiwan is the main source of sectionally integrated CST. The vertically integrated CST also shows significant variations in the 6-15 month period band to the northeast of Taiwan as well. The temporal variations of the sectionally integrated and vertically integrated CST are both controlled primarily by geostrophic transport and modulated by bottom Ekman transport. In the upper 50 m, the geostrophic current to the northeast of Taiwan exhibits large mean and significant variability. The empirical orthogonal function analysis of vertical structure of geostrophic current shows two significant modes with strong annual signal. The first mode is associated with the migration of Kuroshio axis near Taiwan, while the second mode is associated with the variation of the meander of the Kuroshio to the northeast of Taiwan.

  6. Dynamics of phytoplankton community structure in the South China Sea in response to the East Asian aerosol input

    NASA Astrophysics Data System (ADS)

    Guo, C.; Yu, J.; Ho, T.-Y.; Wang, L.; Song, S.; Kong, L.; Liu, H.

    2012-04-01

    Recent studies have demonstrated atmospheric deposition as an important source of bioreactive compounds to the ocean. The South China Sea (SCS), where aerosol loading is among the highest in the world, however, is poorly studied, particularly on the in situ response of phytoplankton community structures to atmospheric deposition. By conducting a series of microcosm bioassays at different hydrographical locations and simulating different aerosol event scales, we observed both positive and negative responses to the input of East Asian (EA) aerosol with high nitrogen (N) and trace metal contents, in terms of biomass, composition and physiological characteristics of phytoplankton communities. High levels of aerosol loading relieved phytoplankton nitrogen and trace metal limitations in SCS, and thus increased total phytoplankton biomass, enhanced their physiological indicators (e.g. photosynthetic efficiency) and shifted phytoplankton assemblages from being dominated by picoplankton to microphytoplanton, especially diatoms. However, under low levels of aerosol loading, the composition shift and biomass accumulation were not apparent, suggesting that the stimulation effects might be counterbalanced by enhanced grazing mortality indicated by increased abundance of protist grazers. Trace metal toxicity of the aerosols might also be the reason for the reduction of picocyanobacteria when amended with high EA aerosols. The magnitude and duration of the deposition event, as well as the hydrographical and trophic conditions of receiving waters are also important factors when predicting the influence of an aerosol deposition event. Our results demonstrated different responses of phytoplankton and microbial food web dynamics to different scales of atmospheric input events in SCS and highlighted the need for achieving an accurate comprehension of atmospheric nutrient on the biogeochemical cycles of the oceans.

  7. Comparative reproductive biology of three dominant myctophids of the genus Diaphus on the slope region of the East China Sea

    NASA Astrophysics Data System (ADS)

    Sassa, Chiyuki; Tanaka, Hiroshige; Ohshimo, Seiji

    2016-09-01

    We examined the reproductive biology of three dominant pseudoceanic myctophids, Diaphus garmani, D. chrysorhynchus, and D. watasei, on the slope region of the East China Sea. Overall, females were more abundant in D. garmani and D. chrysorhynchus, while males were more abundant in D. watasei. The gonadosomatic index (GSI) at 50% sexual maturity of females of D. garmani, D. chrysorhynchus, and D. watasei was 3.65, 3.92, and 6.27, respectively. Based on these criteria, females of each species can mature at sizes larger than 42, 71, and 120 mm standard length (SL), respectively. In all three species, GSI of females showed high values during summer, i.e. the primary spawning season, and occurrence of females with hydrated ovaries was restricted to the daytime (0600-1530 h) in the mesopelagic layer of 270-450 m depth. Oocytes at various sizes were found in mature ovaries, indicating that they are multiple spawners. Spawning frequencies were estimated to be approximately 3-9 days. Mean egg size at hydration and batch fecundity was respectively smallest and lowest in D. garmani (0.60 mm and 612-2200 eggs) and largest and highest in D. watasei (0.65 mm and 10,356-44,879 eggs). Batch fecundity increased linearly with SL in all species, with a steeper slope in D. watasei. Diaphus garmani is characterized by early maturation at a smaller size, while D. watasei channels a larger part of the energy budget into somatic growth during the juvenile and later immature stages (<120 mm SL) than the other two species and subsequently reproduces at a larger size as mature adults.

  8. Variation of levels and distribution of N-nitrosamines in different seasons in drinking waters of East China.

    PubMed

    Li, Ting; Yu, Dian; Xian, Qiming; Li, Aimin; Sun, Cheng

    2015-08-01

    We surveyed the occurrence of nine N-nitrosamine species in ten bottled drinking waters from supermarket and other water samples including raw waters, finished waters, and distribution system waters from nine municipal drinking water treatment plants in eight cities of Jiangsu Province, East China. N-nitrosodimethylamine (NDMA) was detected in one of ten bottled drinking water samples at concentration of 4.8 ng/L and N-nitrosomorpholine (NMor) was detected in four of the ten bottles with an average concentration and a standard deviation of 16 ± 15 ng/L. The levels of nitrosamines in the distribution system water samples collected during summer season ranged from below detection limit (BDL) to 5.4 ng/L for NDMA, BDL to 9.5 ng/L for N-nitrosomethylethylamine (NMEA), BDL to 2.7 ng/L for N-nitrosodiethylamine (NDEA) and BDL to 8.5 ng/L for N-nitrosopyrrolidine (NPyr). Samples of distribution system waters collected in winter season had levels of nitrosamines ranged from BDL to 45 ng/L for NDMA, BDL to 5.2 ng/L for NPyr, and BDL to 309 ng/L for N-nitrosopiperidine (NPip). A positive correlation of the concentration of NDMA as well as the total nine N-nitrosamines between finished waters and distribution system waters was observed. Both dissolved organic carbon and nitrite were found to correlate linearly with N-nitrosamine levels in raw waters.

  9. Geomorphic change in Dingzi Bay, East China since the 1950s: impacts of human activity and fluvial input

    NASA Astrophysics Data System (ADS)

    Tian, Qing; Wang, Qing; Liu, Yalong

    2016-11-01

    This study examines the geomorphic evolution of Dingzi Bay, East China in response to human activity and variations in fluvial input since the 1950s. The analysis is based on data from multiple mathematical methods, along with information obtained from Remote Sensing, Geographic Information System and Global Position System technology. The results show that the annual runoff and sediment load discharged into Dingzi Bay display significant decreasing trends overall, and marked downward steps were observed in 1966 and 1980. Around 60%-80% of the decline is attributed to decreasing precipitation in the Wulong River Basin. The landform types in Dingzi Bay have changed significantly since the 1950s, especially over the period between 1981 and 1995. Large areas of tidal flats, swamp, salt fields, and paddy fields have been reclaimed, and aquaculture ponds have been constructed. Consequently, the patterns of erosion and deposition in the bay have changed substantially. Despite a reduction in sediment input of 65.68% after 1966, low rates of sediment deposition continued in the bay. However, deposition rates changed significantly after 1981 owing to large-scale development in the bay, with a net depositional area approximately 10 times larger than that during 1961-1981. This geomorphic evolution stabilized following the termination of large-scale human activity in the bay after 1995. Overall, Dingzi Bay has shown a tendency towards silting-up during 1952-2010, with the bay head migrating seaward, the number of channels in the tidal creek system decreasing, and the tidal inlet becoming narrower and shorter. In conclusion, largescale development and human activity in Dingzi Bay have controlled the geomorphic evolution of the bay since the 1950s.

  10. Levels of flame retardants HBCD, TBBPA and TBC in surface soils from an industrialized region of East China.

    PubMed

    Tang, Jianfeng; Feng, Jiayong; Li, Xinhu; Li, Gang

    2014-05-01

    Hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA) are of increasing concern because of their potential environmental persistence, bioaccumulation and toxicity. Tris-(2,3-dibromopropyl)isocyanurate (TBC) is another brominated flame retardant (BFR) which has recently been found in the environment and begun to attract attention. The objective of this study is to determine the concentration of these three BFRs in surface soil samples collected from a heavily industrialized and urbanized region in East China. Levels of ∑HBCDs ranged from below detection limits (0.020 ng g(-1)) to 102.6 ng g(-1) on a dry weight basis (dw) with a median level of 15.8 ng g(-1) dw. For TBBPA, the concentration ranged from below detection limits (0.025 ng g(-1)) to 78.6 ng g(-1) dw with a median level of 9.17 ng g(-1) dw. TBC was found at relatively lower concentrations ranging from below detection limits (0.024 ng g(-1)) to 16.4 ng g(-1) dw with a median level of 0.95 ng g(-1) dw. The concentrations of these three BFRs are significantly positively correlated, indicating a common source. Variable BFRs levels were found in different types of soils, with significantly higher concentrations observed at waste dumping sites and industrial areas. The diastereoisomer profiles of HBCDs in most of the soil samples differed from those of the commercial products. The mass inventories of HBCDs, TBBPA and TBC in this region gave preliminarily estimates of 6.68, 2.67 and 0.85 kg, respectively. Therefore, the ubiquitous contamination of soils by these BFRs may well reflect their widespread usage in the study area.

  11. Fine processing and analysis of seabed topographic features in the outer shelf of the north of the East China Sea

    NASA Astrophysics Data System (ADS)

    Tang, Q.; Zhou, X.; Ding, J.; Chen, Y.

    2015-12-01

    On the outer shelf of the north of the East China Sea, seabed ridges and troughs are widely distributed consecutively. The seabed bedforms are in the area where Yellow Sea Trough extends to the Okinawa Trough and lies in the entrance channel of Yellow Sea Warm Current (YSWC), one branch of the Kuroshio Current. The fine post-processing and characteristic analysis for seabed bedforms data will contribute to an overall understanding of seabed topographic features and distribution of the ridges and troughs. Based on the high-precision multi-beam echo sounder (MBES) data, we create a high-precision seabed Digital Terrain Model (DTM) and sonar mosaic images to generate high-resolution 3D seabed maps, as well as seabed slope, aspect maps and other special terrain profiles. From those maps, we can measure height, width, length, direction and other characteristic parameters of the seabed Rippled Scour Depressions (RSDs) and sand ridges. We find a deep seabed gully with the water depth of 153.2 m in the northeast corner of the study area. The relative height difference is up to 32 m indicates strong erosion with dramatic changes in seabed topography. There are also more than 10 large-scale straight RSDs and sand ridges, all NW-SE direction, in length from a few kilometers to 40 km. The general height difference is about 5 m and the maximum height difference can reach up to 10 m. In the study area we find out a great quantity of seabed sand ridges and erode RSDs, which form ridges-troughs and erosion-deposition special seabed topographic features.

  12. Spatiotemporal variations of phytoplankton in the East China Sea and the Yellow Sea revealed by lipid biomarkers

    NASA Astrophysics Data System (ADS)

    Wu, Peng; Bi, Rong; Duan, Shanshan; Jin, Haiyan; Chen, Jianfang; Hao, Qiang; Cai, Yuming; Mao, Xinyan; Zhao, Meixun

    2016-01-01

    The East China Sea (ECS) and the Southern Yellow Sea (SYS) ecosystem is undergoing dramatic changes, but the spatiotemporal patterns and forcing mechanisms of phytoplankton variations remain understudied. Phytoplankton lipid biomarkers are useful proxies for productivity and community structure changes, and they were measured in suspended particles of more than 81 sites from spring and summer of 2011 in the ECS and SYS. In spring, the concentrations of brassicasterol (4.7-127 ng L-1) and dinosterol (0.7-37 ng L-1) were markedly higher in the northern and central SYS, while C37 alkenones (0-15 ng L-1) were detected at only seven sites in the ECS. In summer, brassicasterol (25.3-1178 ng L-1) and dinosterol (0-125 ng L-1) showed high values off the Changjiang River Estuary (CRE), while C37 alkenones (0-410 ng L-1) had high values in the northwest and central SYS. The mean concentrations of the three lipid biomarkers in summer were 3 to 61 times higher than those in spring. Spatiotemporal patterns of biomarkers reveal higher ratios of diatom/dinoflagellate and diatom/haptophyte in higher productivity areas, off the CRE in summer and the northern and central SYS in spring. This study validates the applicability of brassicasterol, dinosterol, and alkenones as proxies of productivity and community structure of the three phytoplankton taxa: diatoms, dinoflagellates, and haptophytes. The results indicate that nutrients (in summer) and turbidity-induced photosynthetic available radiation (in spring) play important roles in regulating spatiotemporal variations of phytoplankton in the ECS and SYS.

  13. Spatial distributions of polyunsaturated aldehydes and their biogeochemical implications in the Pearl River Estuary and the adjacent northern South China Sea

    NASA Astrophysics Data System (ADS)

    Wu, Zhengchao; Li, Qian P.

    2016-09-01

    This study reports the first comprehensive exploration of the spatial patterns of dissolved and particulate polyunsaturated aldehydes (PUAs), their physical and biological controlling factors, and their potential biogeochemical influences in the Pearl River Estuary (PRE) of the northern South China Sea (NSCS). High levels of total particulate PUAs (0-41 nM) and dissolved PUAs (0.10-0.37 nM) were observed with substantial spatial variation during an intense summer phytoplankton bloom outside the PRE mouth. We found the particulate PUAs strongly correlated with temperature within the high chlorophyll bloom, while showing a generally positive correlation with chlorophyll-a for the entire region. Additionally, the Si/N ratio significantly correlated with the particulate PUAs along the estuary suggesting the important role of silica on PUA production in this region. The dissolved PUAs counterparts exhibited a positive correlation with chlorophyll-a within the high chlorophyll bloom, but a negatively one with temperature outside, reflecting the essential bio-physical coupling effects on the dissolved PUAs distributions in the ocean. Biogeochemical implications of PUAs on the coastal ecosystem include not only the deleterious restriction of high PUAs-producing diatom bloom on copepod population, but also the profound influence of particulate PUAs on the microbial cycling of organic carbon in the NSCS.

  14. A review of the paleomagnetic data from Cretaceous to lower Tertiary rocks from Vietnam, Indochina and South China, and their implications for Cenozoic tectonism in Vietnam and adjacent areas

    NASA Astrophysics Data System (ADS)

    Cung, Thu'ọ'ng Chí; Geissman, John W.

    2013-09-01

    Available paleomagnetic data from rock formations of Cretaceous age from Vietnam, Indochina and South China are compiled and reviewed in the context of their tectonic importance in a common reference frame with respect to Eurasia's coeval paleopoles. Key factors that play an important role in determining the reliability of a paleomagnetic result for utilization in tectonic studies have been taken into consideration and include the absence of evidence of remagnetization, which is a feature common to many rocks in this region. Overall, the Cretaceous paleomagnetic data from the South China Block show that the present geographic position of the South China Block has been relatively stable with respect to Eurasia since the mid-Cretaceous and that the paleomagnetically detected motion of a coherent lithospheric block must be based on the representative data obtained from different specific localities across the block in order to separate more localized, smaller scale deformation from true lithosphere scale motion (translation and/or rotation) of a tectonic block. Cretaceous to early Tertiary paleomagnetic data from the Indochina-Shan Thai Block reveal complex patterns of intra-plate deformation in response to the India-Eurasia collision. Paleomagnetically detected motions from the margins of tectonic blocks are interpreted to mainly reflect displacement of upper crustal blocks due to folding and faulting processes. Rigid, lithosphere scale block rotation is not necessarily supported by the paleomagnetic data. The paleomagnetic results from areas east and south of the Red River fault system suggest that this major transcurrent fault system has had a complicated slip history through much of the Cenozoic and that it does not demarcate completely non-rotated and significantly rotated parts of the crust in this area. However, most paleomagnetic results from areas east and south of the Red River fault system at the latitude of Yunnan Province are consistent with a very modest

  15. Distinct groundwater recharge sources and geochemical evolution of two adjacent sub-basins in the lower Shule River Basin, northwest China

    NASA Astrophysics Data System (ADS)

    Wang, Liheng; Dong, Yanhui; Xie, Yueqing; Song, Fan; Wei, Yaqiang; Zhang, Jiangyi

    2016-12-01

    Based on analysis of groundwater hydrogeochemical and isotopic data, this study aims to identify the recharge sources and understand geochemical evolution of groundwater along the downstream section of the Shule River, northwest China, including two sub-basins. Groundwater samples from the Tashi sub-basin show markedly depleted stable isotopes compared to those in the Guazhou sub-basin. This difference suggests that groundwater in the Tashi sub-basin mainly originates from meltwater in the Qilian Mountains, while the groundwater in the Guazhou sub-basin may be recharged by seepage of the Shule River water. During the groundwater flow process in the Tashi sub-basin, minerals within the aquifer material (e.g., halite, calcite, dolomite, gypsum) dissolve in groundwater. Mineral dissolution leads to strongly linear relationships between Na+ and Cl- and between Mg2++ Ca2+ and SO4 2- + HCO3 -, with stoichiometry ratios of approximately 1:1 in both cases. The ion-exchange reaction plays a dominant role in hydrogeochemical evolution of groundwater in the Guazhou sub-basin and causes a good linear relationship between (Mg2++ Ca2+)-(SO4 2- + HCO3 -) and (Na++ K+)-Cl- with a slope of -0.89 and also results in positive chloroalkaline indices CAI 1 and CAI 2. The scientific results have implications for groundwater management in the downstream section of Shule River. As an important irrigation district in Hexi Corridor, groundwater in the Guazhou sub-basin should be used sustainably and rationally because its recharge source is not as abundant as expected. It is recommended that the surface water should be used efficiently and routinely, while groundwater exploitation should be limited as much as possible.

  16. Spatial and Seasonal Dynamics of Ship Emissions over the Yangtze River Delta and East China Sea and Their Potential Environmental Influence.

    PubMed

    Fan, Qianzhu; Zhang, Yan; Ma, Weichun; Ma, Huixin; Feng, Junlan; Yu, Qi; Yang, Xin; Ng, Simon K W; Fu, Qingyan; Chen, Limin

    2016-02-02

    The Yangtze River Delta (YRD) port cluster is one of five major port clusters in China and is home to Shanghai port, the largest port worldwide. In this study, an automatic identification system-based model was built to estimate the ship exhaust emissions in the YRD and the East China Sea within 400 km of the coastline. In 2010, the total emissions of SO2, NOX, and PM2.5 were 3.8 × 10(5) tonnes/yr, 7.1 × 10(5) tonnes/yr, and 5.1 × 10(4) tonnes/yr, respectively. More than 60% and 85% of the ship emissions occurred within 100 km and 200 km of the coastline, respectively. Ship emissions also showed distinct seasonal variability. The emission of SO2 and NOX by ships in hot spots, such as ports and vessel traffic hubs was much higher than that on land, with maximum SO2 and NOX intensities from ships that were 36 times and 17 times greater, respectively, than the maximal land-based emissions. The potential impact of ship emissions at six hot spots on the surrounding atmospheric environment was estimated with the HYSPLIT model. Our study demonstrated that ship emissions have an important impact on both the entire YRD region and on greater East China.

  17. The concurrent variability of East Asian subtropical and polar-front jets and its implication for the winter climate anomaly in China

    NASA Astrophysics Data System (ADS)

    Xiao, Chuliang; Zhang, Yaocun; Lofgren, Brent M.; Nie, Yu

    2016-06-01

    The variability of East Asian upper level westerly jets in winter is studied with regard to the concurrent existence of subtropical jet (East Asian subtropical jet (EASJ)) and polar-front jet (East Asian polar-front jet (EAPJ)) using the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis. In the distribution of jet occurrence revealed in 6-hourly data, two jet branches along 30°N and 55°N, corresponding to locations of EASJ and EAPJ, respectively, are separated over the Tibetan Plateau. The leading two modes of zonal-mean zonal wind in East Asia extracted from a mass-weighted empirical orthogonal function analysis are characterized by the intensity changes and location displacements of two jets. The key regions for EASJ and EAPJ are then defined to represent variabilities of these two jets. Correlation analysis indicates that the subseasonal variation of EAPJ precedes EASJ by around 5 days, which can be interpreted as wave-mean flow interactions via synoptic-scale transient eddy activities. Based on the pentad intensity indices of two jets, the concurrent variabilities of EASJ and EAPJ are investigated with typical temperature and precipitation anomalies in China. The results suggest that by taking account of the two jets, we are able to get a more comprehensive understanding of the winter climate.

  18. Chemical composition and mass size distribution of PM1 at an elevated site in central east China

    NASA Astrophysics Data System (ADS)

    Zhang, Y. M.; Zhang, X. Y.; Sun, J. Y.; Hu, G. Y.; Shen, X. J.; Wang, Y. Q.; Wang, T. T.; Wang, D. Z.; Zhao, Y.

    2014-11-01

    Size-resolved aerosol chemical compositions were measured continuously for 1.5 years from June 2010 to January 2012 with an aerosol mass spectrometer (AMS) to characterize the mass and size distributions (MSDs) of major chemical components in submicron particles (approximately PM1) at Mountain Tai (Mt. Tai), an elevated site in central east China. The annual mean mass concentrations of organic, sulfate, nitrate, ammonium, and chloride were 11.2, 9.2, 7.2, 5.8, and 0.95 μg m-3, respectively, which are much higher than those at most mountain sites in the USA and Europe, but lower than those at the nearby surface rural sites in China. A clear seasonality was observed for all major components throughout the study, with low concentration in fall and high in summer, and is believed to be caused by seasonal variations in planetary boundary layer (PBL) height, near surface pollutant concentrations and regional transport processes. Air masses were classified into categories impacted by PBL, lower free troposphere (LFT), new particle formation (NPF), in-cloud processes, and polluted aerosols. Organics dominated the PM1 mass during the NPF episodes, while sulfate contributed most to PM1 in cloud events. The average MSDs of particles between 30 and 1000 nm during the entire study for organics, sulfate, nitrate, and ammonium were approximately log-normal with mass median diameters (MMDs) of 539, 585, 542, and 545 nm, respectively. These values are slightly larger than those observed at ground sites within the North China Plain (NCP), likely due to the relative aged and well-mixed aerosol masses at Mt. Tai. There were no obvious differences in MMDs during the PBL, LFT, in-cloud and polluted episodes, but smaller MMDs, especially for organics, were observed during the NPF events. During the PBL, NPF, and polluted episodes, organics accounted for major proportions at smaller modes, and reached 70% at 100-200 nm particles in the polluted events. In cloud episodes, inorganics

  19. The simulation of a storm surge and wave due to Typhoon Sarah using an integrally coupled tide-surge-wave model of the Yellow and East China Seas

    NASA Astrophysics Data System (ADS)

    Yuk, Jin-Hee; Kim, Kyeong Ok; Choi, Byung Ho

    2015-12-01

    The Yellow and East China Seas are characterized by shallow shelf seas, seasonal monsoons and typhoons, especially the Korean Peninsula's western coastal area, which features large tides, a complex coastline and many islands. This study implemented an integrally coupled tide-surge-wave model based on an unstructured grid to evaluate the impact of Typhoon Sarah, which occurred in September of 1959, on the Yellow and East China Seas and, specifically, the southern coast of Korea in terms of waves and storm surges. The model results projected a significant wave height of 2-7 m, a mean wave period of 4-14 sec, and positive surge heights that were 0.3-1 m along the southern coast of Korea. Additional model runs included two independent model runs for waves and tides, and one tide-surge model run was conducted to investigate the interactions in the wave, tide and storm surge processes. The coupled tide-surgewave model reasonably reproduced wave properties and storm surges, but uncoupled models, i.e. independent models, slightly overestimated waves and surges. The wave forces associated with the gradient radiation stress resulted in water being elevated into coastal regions, thereby the water elevation increased onshore and the reverse happened offshore. A possible water level change due to a storm equivalent to Typhoon Sarah in the year 2100 was estimated by considering a mean sea level rise of 70 cm and was generally in the range of 70-100 cm in the Yellow and East China Seas and approximately 68 cm along the southern coast of Korea.

  20. China in Maps 1890-1960: A Selective and Annotated Cartobibliography. East Asia Series Occasional Paper No. 4.

    ERIC Educational Resources Information Center

    Williams, Jack F.

    This study is an extensive bibliography of government-published maps relating to China that have been produced by the United States, Japan, China, Great Britain, Germany, France, and the Union of Soviet Socialist Republics. Several introductory, narrative chapters discuss the development of modern mapping in China and various mapping activities of…

  1. δ 18Osw estimate for Globigerinoides ruber from core-top sediments in the East China Sea

    NASA Astrophysics Data System (ADS)

    Horikawa, Keiji; Kodaira, Tomohiro; Zhang, Jing; Murayama, Masafumi

    2015-12-01

    The paired analyses of the Mg/Ca ratio and oxygen isotopic composition ( δ 18Oc) of surface-dwelling planktonic foraminifera have become a widely used method for reconstructing the oxygen isotopic composition of ambient seawater ( δ 18Osw) as a robust proxy for surface salinity. Globigerinoides ruber ( G. ruber) is a mixed-layer dweller, and its fossil shell is an ideal archive for recording past sea surface water conditions, such as those caused by variability in the East Asian summer monsoon (EASM). Here, we investigate the validity of shell-derived δ 18Osw estimates for G. ruber using core-top sediments from the East China Sea (ECS). First, we determined a local δ 18Osw-salinity equation for the eastern part of the ECS in July [ δ 18Osw = -7.74 + 0.23 × salinity]. Then, we calculated δ 18Osw from core-top δ 18Oc and Mg/Ca values in G. ruber using the δ 18Oc-temperature equation of Bemis et al. (Paleoceanography 13(2):150-160, 1998) and the Mg/Ca-temperature equation of Hastings et al. (EOS 82:PP12B-10, 2001). The core-top δ 18Osw and salinity were estimated to be in the ranges of -0.2 to +0.39 ‰ and 33.7 to 34.5, respectively, which fall close to the local δ 18Osw-salinity regression line. The core-top data showed that the Mg/Ca-temperature calibration by Hastings et al. (EOS 82:PP12B-10, 2001) and the δ 18Oc-temperature equation by Bemis et al. (Paleoceanography 13(2):150-160, 1998) are appropriate for calculating δ 18Osw in the ECS. Furthermore, we measured core-top Ba/Ca ratios of G. ruber (Ba/Ca G. ruber ), which ranged from 0.66 to 2.82 μmol mol-1. There was not a significant relationship between the salinity and Ba/Ca G. ruber ratios due to the highly variable Ba/Ca G. ruber data. Given the seawater Ba/Ca data and the published partition coefficient for Ba ( D Ba = 0.15-0.22), pristine Ba/Ca G. ruber ratios at northern Okinawa Trough sites should be less than 0.84 μmol mol-1. Anomalously high Ba/Ca G. ruber ratios (>0.84 μmol mol-1) might

  2. Significant impact of the East Asia monsoon on ozone seasonal behavior in the boundary layer of Eastern China and the west Pacific region

    NASA Astrophysics Data System (ADS)

    He, Y. J.; Uno, I.; Wang, Z. F.; Pochanart, P.; Li, J.; Akimoto, H.

    2008-12-01

    The impact of the East Asia monsoon on the seasonal behavior of O3 in the boundary layer of Eastern China and the west Pacific region was analyzed for 2004-2006 by means of full-year nested chemical transport model simulations and continuous observational data obtained from three inland mountain sites in central and eastern China and three oceanic sites in the west Pacific region. The basic common features of O3 seasonal behaviors over all the monitoring sites are the pre- and post-monsoon peaks with a summer trough. Such bimodal seasonal patterns of O3 are predominant over the region with strong summer monsoon penetration, and become weaker or even disappear outside the monsoon region. The seasonal/geographical distribution of the pre-defined monsoon index indicated that the East Asia summer monsoon is responsible for the bimodal seasonal O3 pattern, and also partly account for the differences in the O3 seasonal variations between the inland mountain and oceanic sites. Over the inland mountain sites, the O3 concentration increased gradually from the beginning of the year, reached a maximum in June, decreased rapidly to the summer valley in July or August, and then peaked in September or October, thereafter decreased gradually again. Over the oceanic sites, O3 abundance showed a similar increasing trend beginning in January, but then decreased gradually from the end of March, followed by a wide trough with the minimum in July and August and a small peak in October or November. A sensitivity analysis performed by setting China-emission to zero revealed that the chemically produced O3 from China-emission contributed substantially to the O3 abundance, particularly the pre- and post-monsoon O3 peaks, over China mainland. We found that China-emission contributed more than 40% to total boundary layer O3 during summertime (60-70% in July) and accounted for about 40 ppb of each peak value over the inland region if without considering the effect of the nonlinear chemical

  3. From food to feed: Assessment of the stationary lift net fishery of East Hainan, Northern South China Sea

    NASA Astrophysics Data System (ADS)

    Krumme, Uwe; Wang, Tian C.; Wang, Dao R.

    2013-04-01

    In the Asia-Pacific region, the increasing demand for low value/trash fish as feed for mariculture drives unsustainable fisheries on already overexploited marine resources. The mariculture demand may also affect artisanal nearshore fisheries operating in shallow nursery grounds, e.g., lift net fisheries, but little is known about how they work. We describe the stationary lift net artisanal fishery on the East coast of Hainan Island (northern South China Sea). A trapezoidal blanket net (mean surface area: 478 m2), stretched between four upright poles at the corners, is lowered and lifted via a rope system from a tower by a single fisher. In 2009 ˜200 households depended on 288 lift nets, 82% of which were located in the Wenchang/Wenjiao estuary. The number of lift nets decreased by 15% from 2007 to 2009. Presently, it is mainly an early retirement activity of fishers with a median age of 52 years and younger men rarely enter the fishery due to low catch rates. However, not one fisher would stop fishing even at 50% hypothetical decline in catch — due to lack of alternatives. Mean catch weight per fishing day is 12 kg (range: 0-1.7 t). In the past, the entire catch was used as food. Presently, an average of 52% of the catch is sold as feed to local pond and floating net cage mariculturists who, subsequently, supply the live food trade to markets as far as Hong Kong. Larger dead fishes are sold at village markets or at Qinglan harbor and are locally or regionally consumed. The density of lift-net operation is highest around the Wenchang/Wenjiao lagoon due to the presence of an extensive sheltered, shallow subtidal area in proximity to mariculture and export markets in Qinglan. Thus, the modern mariculture demand for low value/trash fish supports the continuation of an ancient artisanal fishery despite severe resource depletion. The existence of similar lift nets in Vietnam points to an exchange in the artisanal fishing knowledge between Vietnam and Hainan

  4. Bacterial community radial-spatial distribution in biofilms along pipe wall in chlorinated drinking water distribution system of East China.

    PubMed

    Liu, Jingqing; Ren, Hongxing; Ye, Xianbei; Wang, Wei; Liu, Yan; Lou, Liping; Cheng, Dongqing; He, Xiaofang; Zhou, Xiaoyan; Qiu, Shangde; Fu, Liusong; Hu, Baolan

    2017-01-01

    Biofilms in the pipe wall may lead to water quality deterioration and biological instability in drinking water distribution systems (DWDSs). In this study, bacterial community radial-spatial distribution in biofilms along the pipe wall in a chlorinated DWDS of East China was investigated. Three pipes of large diameter (300, 600, and 600 mm) were sampled in this DWDS, including a ductile cast iron pipe (DCIP) with pipe age of 11 years and two gray cast iron pipes (GCIP) with pipe ages of 17 and 19 years, and biofilms in the upper, middle, and lower parts of each pipe wall were collected. Real-time quantitative polymerase chain reaction (qPCR) and culture-based method were used to quantify bacteria. 454 pyrosequencing was used for bacterial community analysis. The results showed that the biofilm density and total solid (TS) and volatile solid (VS) contents increased gradually from the top to the bottom along the pipe wall. Microorganisms were concentrated in the upper and lower parts of the pipe wall, together accounting for more than 80 % of the total biomass in the biofilms. The bacterial communities in biofilms were significantly different in different areas of the pipe wall and had no strong interaction. Compared with the upper and lower parts of the pipe wall, the bacterial community in the middle of the pipe wall was distributed evenly and had the highest diversity. The 16S rRNA genes of various possible pathogens, including Escherichia coli, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Salmonella enterica, were detected in the biofilms, and the abundances of these possible pathogens were highest in the middle of the pipe wall among three areas. The detachment of the biofilms is the main reason for the deterioration of the water quality in DWDSs. The results of this study suggest that the biofilms in the middle of the pipe wall have highly potential risk for drinking water safety, which provides new ideas for the study of the microbial ecology in

  5. Influence of the Changjiang River on the light absorption properties of phytoplankton from the East China Sea

    NASA Astrophysics Data System (ADS)

    Wang, S. Q.; Ishizaka, J.; Yamaguchi, H.; Tripathy, S. C.; Hayashi, M.; Xu, Y. J.; Mino, Y.; Matsuno, T.; Watanabe, Y.; Yoo, S. J.

    2014-04-01

    Phytoplankton light absorption properties were investigated at the surface and subsurface chlorophyll a maximum (SCM) layer in the East China Sea (ECS), a marginal sea which is strongly influenced by the Changjiang discharge in summer. Results from ECS were compared with those from the Tsushima Strait (TS) where the influence of Changjiang discharge is less. The probable controlling factors, packaging effect (cell size) and pigment composition of total chlorophyll a (Tchl a)-specific absorption coefficient (aph*(λ)) were examined by the corresponding measurements of pigments identified by high-performance liquid chromatography. We observed distinct phytoplankton size structure and thereby absorption properties between ECS and TS. At the surface, mixed populations of micro-, nano- and pico-phytoplankton were recorded in ECS while pico-phytoplankton dominated in TS, generating a lower average aph*(λ) in ECS than in TS. Within SCM, average aph*(λ) was higher in ECS than in TS because of the dominance of nano- and micro-phytoplankton in ECS and TS, respectively. By pooling surface and SCM samples, we found regular trends in phytoplankton size-fraction versus Tchl a; and correlations between aph*(λ) and Tchl a consistent with previous observations for the global ocean in TS but not in ECS. In ECS phytoplankton size-fraction was not correlated with Tchl a, which consequently caused poor relationships between aph*(λ) and Tchl a. The abnormal values mainly originated from the surface low-salinity waters and SCM waters beneath them. At high Tchl a, aph*(λ) of these samples was substantially higher compared to the values in TS and from the global regressions, which was attributable to the lower micro-phytoplankton fraction, and higher nano- and/or pico-phytoplankton fractions in ECS. These observations indicated that the distinct light absorption properties of phytoplankton in ECS were possibly influenced by the Changjiang discharge. Our

  6. Study on shallow-water delta characteristics by utilizing seismic sedimentologic methods in Zilaitun Oilfield, Huanghua Depression, East China

    NASA Astrophysics Data System (ADS)

    Liu, Shan; Wang, Jiahao

    2015-04-01

    Shallow-water delta is characterized by widely distributed distributary channels from plentiful previous studies. But how to tenuously depict its planar geomorphology remains a difficult problem at present. This paper discussed the feasibility of seismic sedimentologic methods to interpret distributary channels distribution and summarized shallow-water delta characteristics. Huanghua Depression of Bohai Bay Basin is the Cenozoic rift basin in east China. Zilaitun Oilfield lies in the Kongdian buried-hill belt of Huanghua Depression. The oil layer is mainly distributed in the Paleocene Kongdian Formation. From core samples, 1st member of Kongdian Formation mainly consists of finer grain-size sandstone and amaranth mudstone, revealing a shallow-water environment. In the sandstone of distributary channels, sedimentary structures such as erosional surface, lag deposit, parallel bedding and trough cross-bedding are developed, illustrating an intensive hydrodynamic condition. Combining logging data, shallow-water delta mainly developed delta front subfacies. Microfacies of the delta front include subaqueous distributary channel, mouth bar and interdistributary bay in study area. A vertical discontinuous sequence was formed on account of the lack of distal bar. Subaqueous distributary channels are characterized by cylinder and conical well log curves. By extraction of RMS amplitudes from 3-D seismic data, seismic strata slices reveal banding distribution of sand bodies. Cylinder and conical logging curves demonstrated that these sand bodies are developed in distributary channels. The NE-trending anastomosing and dendritic distributary channels are widely developed in 1st member of Kongdian Formation. When the lake expanded, the river frequently bifurcated and diverted due to the rise of the relative lake-level, forming deep and wide anastomosing distributary channels. These channels extended as far as 13.2 km. The width is from 600 m to 1000 m. The average thickness of

  7. Distinction and grain-size characteristics of intertidal heterolithic deposits in the middle Qiantang Estuary (East China Sea)

    NASA Astrophysics Data System (ADS)

    Fan, Daidu; Shang, Shuai; Cai, Guofu; Tu, Junbiao

    2015-06-01

    The routine sampling procedure for grain-size analysis of intertidal heterolithic deposits runs a high risk of inadvertent mixing of two or more different sedimentation units, which would consequently complicate data interpretation. Traditionally, sedimentologists pay less attention to muddy layers due to a lack of internal structures, although the grain-size populations of such layers should encode more information on fine-mud flocculation processes than sandy layers. In this paper, individual muddy and sandy layers of nine short cores from the Da-Jian-Shan tidal flats of the middle Qiantang Estuary in the East China Sea, which experiences tidal bores, were sampled separately for grain-size analysis. A core taken at Huang-Jia-Yan from the lower estuary, not affected by tidal bores, served for comparison. A curve-fitting method was employed to decompose each grain-size distribution into two Gaussian populations. Cumulative plots indicate that intertidal sediments are mostly dispersed as intermittent and uniform suspension loads, traction loads being absent or very subordinate. This is conceivably linked to flows agitated by tidal bores, and to the highly dynamic nature of fine sand and coarse silt particles. Selective transport and deposition have produced three distinct sedimentation units, namely, tidal-bore deposits, tidal sandy deposits, and tidal muddy deposits. These can also be discriminated on bivariate plots of any two textural parameters. Shoreward attenuation of tidal flows is reflected in the gradual fining and thinning of sandy layers from lower-flat massive sands, through middle-flat hybrid deposits (alternations of massive sands and tidal rhythmites), to upper-flat tidal rhythmites. This gradient is also well represented in slightly decreasing (increasing) sorting and decreasing (increasing) proportions of the coarser (finer) hydraulic populations in the muddy layers. Although no corresponding trends are discernible in the hydraulic populations of

  8. The lower Triassic microbiolites in Chaohu region, East China and their contribution to the early Triassic recovery

    NASA Astrophysics Data System (ADS)

    Jia, Zhihai; Zhang, Liwei; Hong, Tianqiu

    2010-05-01

    The lower Triassic is well preserved in Chaohu Region, Anhui Province, East China. It can be divided into Yinkeng Formation (80 meters thick, was formed during the Indian and early Smitian), Helongshan Formation (21 meters thick, was formed during the end Smithian) and Nanlinghu Formation (more than 157 meters thick, was formed during the Spathian) from bottom to top. It is mainly composed of carbonatites such as micrite limestones and nodular limestones, as well as shales and calcareous marls. The lower Triassic in this area has been well researched for more than a decade, and many fossils such as ammonites, bivalves, fishes, ichthyosaurus, conodonts, and ichnofossils have been found, but the microbiolites have been neglected. Microbiolites were mainly outcropped in the Helongshan Formaiton and the lower Nanlinghu Formation. In the lower Helongshan Formaiton, tens microbial mat layers and thin bedded calcareous marl layers formed cyclothems which have been named as nodular limstones. The thin-section observation of the microbial mats indicate that many films and thin-shell bivalve fragments deposited almost horizontally. In the upper Helongshan Formaiton, six microstromatolite bioherm layers were outcropped in the thin bedded calcareous marl layers. The diameter of the stromatolite column is about 2 millimeters, the bioherms are lenticular and no more than 3 centimeters thick in the central, their diameters change from 5 centimeters to 30 centimeters, calcareous marls were deposited around the bioherms, and many ammonoids, bivalves and burrows were found in such layers. The microfacies differentiation of the stromatolites such as the basement, reef core and the capping beds can be recognised clearly in thin sections. Several microstromatolite layers were outcropped in the micritic limestones with a stable thickness of 15 millimeters in the lower Nanlinghu Formation and the stromatolite column look like the ones in the Helongshan Formation. Few microbiolites have

  9. Decline in suspended sediment concentration delivered by the Changjiang (Yangtze) River into the East China Sea between 1956 and 2013

    NASA Astrophysics Data System (ADS)

    Dai, Zhijun; Fagherazzi, Sergio; Mei, Xuefei; Gao, Jinjuan

    2016-09-01

    The temporal evolution of suspended sediment concentration (SSC) in a river debouching into the ocean provides vital insights into erosion processes in the watershed and dictates the evolution of the inner continental shelf. While the delivery of sediment from rivers to the ocean has received special attention in the recent past, few studies focused on the variability and dynamics of river SSC, especially in the Changjiang (Yangtze) river, China, the longest river in Asia. Here, variations in SSC delivered by the Changjiang River to the East China Sea and possible causes of its variability were detected based on a long-term time series of daily SSC and monthly water discharge measured at the Datong gauging station. The SSC data are further compared to a hydrological analysis of yearly precipitation covering the entire catchment. The results indicate the presence of a decline in SSC in the period 1956-2013, which can be divided into three phases: (i) high SSC (0.69 kg/m3) in the wet season and low SSC (0.2 kg/m3) in the dry season from 1956 to 1970; (ii) relative high SSC (0.58 kg/m3) in the wet season and low SSC (0.15 kg/m3) in the dry season from 1971 to 2002; and (iii) low SSC (0.19 kg/m3) in the wet season and very low SSC (0.09 kg/m3) in the dry season after 2002. These three periods have a mean yearly SSC values of 0.62, 0.42, and 0.18 kg/m3, respectively. Compared with 1956-1970, the slope of the rating curve between SSC and water discharge decreased, respectively, by 2% and 30% during the period 1971-2002 and 2002-2013. Soil erosion, dam construction, and banks reinforcement along the Changjiang River are the main causes of SSC variations. Fluctuations in water discharge are also controlling the SSC long-term variations. Specifically, from 1956 to 1970, the effect of soil erosion overrules that of dam impoundment, which is likely responsible for the high SSC; during the period 1970-2002, the influence of dam impoundment increases while that of soil erosion

  10. Acoustics and Oceanographic Observations Collected During the QPE Experiment by Research Vessels OR1, OR2 and OR3 in the East China Sea in the Summer of 2009

    DTIC Science & Technology

    2010-08-01

    OR1, OR2 and OR3 in the East China Sea in the Summer of 2009 by Arthur E. Newhall1, James F. Lynch1, Glen G. Gawarkiewicz1, Timothy F. Duda1, Neil M...Vessels OR1, OR2, and OR3 in the East China Sea in the Summer of 2009 Arthur E. Newhall, James F. Lynch, Glen G. Gawarkiewicz,  Timothy F. Duda, Neil M...number: N00014­08­1­0763 Keywords:   QPE experiment and mooring information   acoustic and oceanography data in the East China  Sea   quantifying

  11. Analysis of Cu, Co, V and Zn in coastal waters of the East China Sea by inductively coupled plasma mass spectrometry (ICP-MS)

    NASA Astrophysics Data System (ADS)

    Yang, Rujun; Ning, Yutong; Zhang, Aibin; Li, Yan; Su, Han

    2016-10-01

    In this study, a simple method for the simultaneous determination of trace metals (Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry (ICP-MS) was developed. This multi-element method enables the simultaneous extraction of four metals, particularly Co and V. The recoveries of Cu, Co, V and Zn after Mg(OH)2 coprecipitation were 73%, 96%, 94% and 92%, which means that our procedure was well-suited to the determination of these four trace metals. The detection limits were 3.81, 0.18, 6.09 and 1.91 nmol L-1, respectively. Then, applying this method to the simultaneous determination of these four metals in coastal water samples from the East China Sea revealed that the concentrations of Cu, Zn, Co and V were higher in bottom waters compared to water at other depths, and higher concentrations were generally observed at the Yangtze River estuary. Additionally, example vertical profiles of dissolved trace metal concentrations for the East China Sea in spring and autumn are compared. These findings indicate that Zn had the greatest seasonal variation followed by Cu, V and Co. For Zn and Co, the concentrations were higher during spring than during autumn. For Cu and V, the seasonal variation in the concentrations was opposite.

  12. On-board flow cytometric observation of picoplankton community structure in the East China Sea during the fall of different years.

    PubMed

    Pan, L A; Zhang, L H; Zhang, J; Gasol, Josep M; Chao, M

    2005-04-01

    On-board flow cytometric determinations of picoplankton abundance (i.e. Synechococcus spp., Prochlorococcus spp., picoeukaryotes and also heterotrophic bacteria) were obtained in the East China Sea in fall of 2000 and 2003. The average abundances of Synechococcus, Prochlorococcus, picoeukaryotes and heterotrophic bacteria were 10(5), 10(5), 10(4) and 10(6) cells ml(-1), respectively. Synechococcus, picoeukaryotes and heterotrophic bacteria were abundant at all the stations and presented higher concentration in the inner shelf where influences from the Changjiang effluent plumes and the coastal upwelling were evident, while Prochlorococcus was absent from the near-shore stations and became the dominant picophytoplankton population in offshore waters, where its abundance was comparable to that for heterotrophic bacteria. All picoplankton groups showed a reduction in cell number with depth, and a positive correlation with water temperature were observed, which reflected the importance of light and temperature on picoplankton growth. A negative relationship with salinity was found for heterotrophic bacteria along two sections across the East China Sea Shelf, and distribution of picoplankton was dominated by different water masses. The fixation could lead to loss in Prochlorococcus cell numbers within one month, and all the picoplankton numbers decreased dramatically after three months.

  13. Future vegetation patterns and primary production in the coastal wetlands of East China under sea level rise, sediment reduction, and saltwater intrusion

    NASA Astrophysics Data System (ADS)

    Ge, Zhen-Ming; Cao, Hao-Bin; Cui, Li-Fang; Zhao, Bin; Zhang, Li-Quan

    2015-10-01

    To explore the effects of sea level rise (SLR), sediment reduction (SR), and saltwater intrusion (SWI) on the vegetation patterns and primary production of one exotic (Spartina alterniflora) and two native dominant (Scirpus mariqueter and Phragmites australis) species in the coastal wetlands of East China, range expansion monitoring and stress experiments were conducted, followed by model prediction. After a rapid invasion period, the expansion rate of S. alterniflora slowed down due to the decreasing availability of suitable habitat under prolonged inundation. SLR was shown to decrease the colonization of S. alterniflora and the native P. australis up to 2100. In contrast, the native S. mariqueter that has a high tolerance of inundation increased in area following SLR, due to a reduction in competition from S. alterniflora in low-lying habitats and even recolonized areas previously invaded by the exotic species. The combination of SLR and SR resulted in further degradation of S. alterniflora and P. australis, while the area of S. mariqueter was not reduced significantly. The decrease in the area of vegetation would reduce the gross primary production under SLR and SR. SWI exacerbates the impacts, especially for P. australis, because S. alterniflora and S. mariqueter have a higher tolerance of salinity. Thus, the coastal vegetation pattern was predicted to be modified due to species-specific adaption to changed geophysical features. This study indicated that the native species better adapted to prolonged inundation and increased salinity might once again become key contributors to primary production on the muddy coasts of East China.

  14. Morphological variability and molecular characterisation of Dichelyne (Cucullanellus) pleuronectidis (Yamaguti, 1935) (Ascaridida: Cucullanidae) from the flatfish Pleuronichthys cornutus (Temminck & Schlegel) (Pleuronectiformes: Pleuronectidae) in the East China Sea.

    PubMed

    Li, Liang; Du, Li-Qiang; Xu, Zhen; Guo, Yan-Ning; Wang, Shu-Xia; Zhang, Lu-Ping

    2014-01-01

    Cucullanid nematodes identified morphologically as Dichelyne (Cucullanellus) pleuronectidis (Yamaguti, 1935) were collected from the ridged-eye flounder Pleuronichthys cornutus (Temminck & Schlegel) (Pleuronectiformes: Pleuronectidae) in the East China Sea. Their examination using light microscopy and, for the first time, scanning electron microscopy, revealed several important, but previously unreported morphological features and the presence of remarkable morphological differences in the intestinal caecum and deirids among some individuals. Consequently, specimens of D. pleuronectidis were characterised using molecular methods by sequencing and analysing the internal transcribed spacer (ITS) of the ribosomal DNA to test whether the present material with broad range of morphological variability, represents a complex of sibling species or a single species. The results of molecular analyses proved that the differences in the intestinal ceacum and deirids should be considered as intraspecific variation and that the nematode material collected from P. cornutus in the East China Sea represented a single species, D. pleuronectidis. These new morphological and genetic data contributed to an accurate diagnosis of this hitherto insufficiently known nematode and also indicated that a more rigorous study based on morphological and genetic data with broader representation of the Cucullanidae is required to assess whether the traditionally used diagnostic character of absence or presence of intestinal ceacum is of generic importance in distinguishing Dichelyne and Cucullanus.

  15. International study on antidepressant prescription pattern at 20 teaching hospitals and major psychiatric institutions in East Asia: Analysis of 1898 cases from China, Japan, Korea, Singapore and Taiwan.

    PubMed

    Uchida, Naoki; Chong, Mian-Yoon; Tan, Chay Hoon; Nagai, Hiroshi; Tanaka, Mariko; Lee, Min-Soo; Fujii, Senta; Yang, Shu-Yu; Si, Tainmei; Sim, Kang; Wei, Hao; Ling, He Yan; Nishimura, Ryoji; Kawaguchi, Yoshichika; Edwards, Glen; Sartorius, Norman; Shinfuku, Naotaka

    2007-10-01

    The purpose of the present study was to review the prescription patterns of antidepressants in different countries in East Asia. The survey was conducted in China, Japan, Korea, Singapore and Taiwan from October 2003 to March 2004 using the unified research protocol and questionnaire. Twenty teaching hospitals and major psychiatric hospitals participated and a total of 1898 patients receiving antidepressants were analyzed. The survey provided a number of interesting characteristics on the prescription patterns of antidepressant in East Asia. Out of 56 antidepressants listed in the Anatomical Therapeutic Chemical Classification (ATC) index by the World Health Organization (WHO) Collaborating Center for Drug Statistics Methodology (Oslo), only 26 antidepressants were prescribed in participating countries in East Asia. On average 38.4% of prescriptions of antidepressants were for patients with diagnoses other than depressive disorders. The availability and commonly prescribed antidepressants varied greatly by country. The selective serotonin re-uptake inhibitors (SSRI) and other newer antidepressants were prescribed in approximately 77.0% of all cases. At the time of the survey, only two SSRI medications were available in Japan. However, five types of SSRI were available and were often prescribed in Korea.

  16. Current progress toward eradicating Helicobacter pylori in East Asian countries: differences in the 2013 revised guidelines between China, Japan, and South Korea.

    PubMed

    Lee, Sun-Young

    2014-02-14

    New 2013 guidelines on Helicobacter pylori (H. pylori) infection have been published in China, Japan, and South Korea. Like the previous ones, these new guidelines differ between the three countries with regard to the indications for H. pylori eradication, diagnostic methods, and treatment regimens. The most profound change among all of the guidelines is that the Japanese national health insurance system now covers the expenses for all infected subjects up to second-line treatment. This makes the Japanese indications for eradication much wider than those in China and South Korea. With regard to the diagnosis, a serum H. pylori antibody test is not recommended in China, whereas it is considered to be the most reliable method in Japan. A decrease relative to the initial antibody titer of more than 50% after 6-12 mo is considered to be the most accurate method for determining successful eradication in Japan. In contrast, only the urea breath test is recommended after eradication in China, while either noninvasive or invasive methods (except the bacterial culture) are recommended in South Korea. Due to the increased rate of antibiotics resistance, first-line treatment is omitted in China and South Korea in cases of clarithromycin resistance. Notably, the Japanese regimen consists of a lower dose of antibiotics for a shorter duration (7 d) than in the other countries. There is neither 14 d nor bismuth-based regimen in the first-line and second-line treatment in Japan. Such differences among countries might be due to differences in the approvals granted by the governments and national health insurance system in each country. Further studies are required to achieve the best results in the diagnosis and treatment of H. pylori infection based on cost-effectiveness in East Asian countries.

  17. Educational Policy Borrowing in China: Looking West or Looking East? Routledge Research in International and Comparative Education

    ERIC Educational Resources Information Center

    Tan, Charlene

    2016-01-01

    For over a decade, Mainland China has been embarking on an ambitious nation-wide education reform ("New Curriculum Reform") for its basic education. The reform reflects China's propensity to borrow selected educational policies from elsewhere, particularly North America and Europe. Chinese scholars have used a local proverb "the…

  18. Significant impact of the East Asia monsoon on ozone seasonal behavior in the boundary layer of Eastern China and the west Pacific region

    NASA Astrophysics Data System (ADS)

    He, Y. J.; Uno, I.; Wang, Z. F.; Pochanart, P.; Li, J.; Akimoto, H.

    2008-08-01

    The impact of the East Asia monsoon on the seasonal behavior of O3 in the boundary layer of Eastern China and the west Pacific region was analyzed for 2004 2006 by means of full-year nested chemical transport model simulations and continuous observational data obtained from three inland mountain sites in central and eastern China and three oceanic sites in the west Pacific region. The basic common features of O3 seasonal behaviors over all the monitoring sites are the pre- and post-monsoon peaks with a summer trough. Such bimodal seasonal patterns of O3 are predominant over the region with strong summer monsoon penetration, and become weaker or even disappear outside the monsoon region. The seasonal/geographical distribution of the pre-defined Monsoon Index indicated that the East Asia summer monsoon is responsible for the bimodal seasonal O3 pattern, and also partly account for the differences in the O3 seasonal variations between the inland mountain and oceanic sites. Over the inland mountain sites, the O3 concentration increased gradually from the beginning of the year, reached a maximum in June, decreased rapidly to a minimum in July or August, and then peaked in September or October, thereafter decreased gradually again. Over the oceanic sites, O3 abundance showed a similar increasing trend beginning in January, but then decreased gradually from the end of March, followed by a wide trough with the minimum in July and August and a small peak in October or November. A sensitivity analysis performed by setting China-emission to zero revealed that the chemically produced O3 from China-emission contributed more than 40% of total boundary layer O3 during summertime (60 70% in June) and accounted for about 40 ppb of each peak value over the inland region. In contrast, over the oceanic region in the high monsoon index zone, the contribution of China-emission to total O3 was always less than 20% (<10 ppb), and less than 10% in summer.

  19. Atmospheric outflow of PM2.5 saccharides from megacity Shanghai to East China Sea: Impact of biological and biomass burning sources

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Chen, Minxuan; Le, Hoa Phuoc; Wang, Fengwen; Guo, Zhigang; Iinuma, Yoshiteru; Chen, Jianmin; Herrmann, Hartmut

    2016-10-01

    In an effort to more fully understand atmospheric outflow of PM2.5-associated saccharide species, we investigated primary saccharides (fructose, glucose, sucrose, and trehalose), saccharide alcohols (arabitol and mannitol), and anhydrosaccharides (levoglucosan and mannosan) in atmospheric aerosols at both a megacity site, Shanghai, and a sea background site, Huaniao Island. The results showed that the saccharide species presented pronounced temporal and spatial variability in the outflow from the megacity to the East China Sea, and varied widely with a total concentration range of 8.6-2400 ng m-3 (283 ng m-3 mean) in Shanghai and 0-1050 ng m-3 (51 ng m-3 mean) in Huaniao Island. Both saccharide species (e.g., levoglucosan and sucrose) showed higher concentrations and a noticeable seasonal gradient during the study period ― there was a high level of levoglucosan in the cold season (161 ng m-3 in winter and 229 ng m-3 in autumn) due to elevated biomass burning activities, and a high level of sucrose in the warm seasons (146 ng m-3 in summer and 145 ng m-3 in spring) due to elevated levels of intense biological aerosols including fungal spores and pollen. The calculated levoglucosan/mannosan (L/M) ratio, which may represent the signature of aerosol particles at the two sites, ranged from 5.2 to 10.9 during the cold season. Back-trajectory analysis results indicated that the saccharides originated from regional sources in East and North China before being transported to the sampling site. Emissions due to biomass burning were estimated to correspond to 46% (mass) of the saccharides quantified in the haze particle samples, whereas biogenic emissions corresponded to 18%, indicating that biomass burning was a considerable aerosol source to the regional atmosphere throughout the year. The results presented here support the theory that levoglucosan could be utilized as a molecular marker for East Asian biomass burning outflow, and sucrose as a molecular marker for

  20. Study of a Wind Front over the Northern South China Sea Generated by the Freshening of the North-East Monsoon

    NASA Astrophysics Data System (ADS)

    Alpers, Werner; Wong, Wai Kin; Dagestad, Knut-Frode; Chan, Pak Wai

    2015-10-01

    Wind fronts associated with cold-air outbreaks from the Chinese continent in the winter are often observed over the northern South China Sea and are well studied. However, wind fronts caused by another type of synoptic setting, the sudden increase or freshening of the north-east monsoon, which is caused by the merging of two anticyclonic regions over the Chinese continent, are also frequently encountered over the northern South China Sea. For the first time, such an event is investigated using multi-sensor satellite data, weather radar images, and a high-resolution atmospheric numerical model. It is shown that the wind front generated by the freshening of the north-east monsoon is quite similar to wind fronts generated by cold-air outbreaks. Furthermore, we investigate fine-scale features of the wind front that are visible on synthetic aperture radar (SAR) images through variations of the small-scale sea-surface roughness. The SAR image was acquired by the Advanced SAR of the European Envisat satellite over the South China Sea off the coast of Hong Kong and has a resolution of 150 m. It shows notches (dents) in the frontal line and also radar signatures of embedded rain cells. This (rare) SAR image, together with a quasi-simultaneously acquired weather radar image, provide excellent data with which to test the performance of the pre-operational version of the Atmospheric Integrated Rapid-cycle (AIR) forecast model system of the Hong Kong Observatory with respect to modelling rain cells at frontal boundaries. The calculations using a horizontal resolution with 3-km resolution show that the model reproduces quite well the position of the notches where rain cells are generated. The model shows further that at the position of the notches the vorticity of the airflow is increased leading to the uplift of warmer, moister air from the sea-surface to higher levels. With respect to the 10-km resolution model, the comparison of model data with the near-surface wind field

  1. Clay mineral contribution from various provenances in the northern South China Sea over the past 400 kyr: implications for the East Asian monsoon evolution

    NASA Astrophysics Data System (ADS)

    Chen, Quan; Liu, Zhifei; Xie, Xin; Kissel, Catherine

    2014-05-01

    Clay mineralogy of Core MD12-3432 taken at 2125 m water depth (CIRCEA cruise on board the R.V. Marion Dufresne, IPEV) in the northern South China Sea was investigated in order to understand the time series contribution of terrigenous sediments from various provenances. With calibration of a low-resolution analysis on carbonate concentration and major elements, we converted the XRF core scanned calcium data into a high-resolution carbonate content records. Through referring to the well-dated carbonate record of nearby Core MD05-2904, we established a reliable age model, indicating about 400 kyr ago at the bottom of Core MD12-3432. The clay mineral assemblage is dominated by smectite (23-59%) and illite (22-43%), with minor chlorite (13-27%) and kaolinite (4-13%). The time series variation of clay mineral assemblages indicates strong glacial-interglacial cyclicity. In general, the variation in smectite content is similar to that of carbonate concentration, with higher values during interglacials than during glacials, while illite and chlorite contents showing opposite patterns. The change in kaolinite content shows an independent pattern with high values during glacials, corresponding well with the illite crystallinity variation. The provenance analysis of these clay minerals suggests three end-member sources: all smectites derive from Luzon, all kaolinites originate from the Pearl River, and illite and chlorite are coming from both the Pearl River and Taiwan. Using the linear separation method of illite crystallinity, a time series of the clay mineral contribution from the three major provenances to the northern South China Sea was reconstructed. Combined with spectral analyses, we suggest the clay mineral contribution from Pearl River was mainly influenced by sea level change, while the East Asian summer monsoon controlled the contribution from Luzon. The strong precipitation rate related to intensive East Asian summer monsoon would have enhanced the denudation and

  2. China’s Perspectives on the Major Island Disputes in the East and South China Seas: Implications for the US’s Strategic Rebalance toward Asia

    DTIC Science & Technology

    2013-02-14

    dynamic, which pertains to the difficulty in resolving island disputes among nations. According to Rodolfo Severino , as it is “most difficult to appear...2012, http://www.cnn.com/2012/06/02/us/panetta-asia/index.html. 10 Rodolfo Severino , “A Code of Conduct for the South China Sea?” Pacific Forum CSIS...2012, http://blogs.voanews.com/state-department-news/2012/09/06/china- says-no-questioning-its-sovereignty-over-south-china-sea/. 39 Rodolfo Severino

  3. 9. PERSPECTIVE OF EAST ELEVATION, SHOT FROM TRACK BED OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. PERSPECTIVE OF EAST ELEVATION, SHOT FROM TRACK BED OF ADJACENT LAKE SHORE & MICHIGAN SOUTHERN RAILWAY BRIDGE. - Pittsburgh, Fort Wayne & Chicago Railway, Calumet River Bridge, Spanning Calumet River, east of Chicago Skyway (I-90), Chicago, Cook County, IL

  4. Oblique view of east end and south side, view facing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Oblique view of east end and south side, view facing northwest - U.S. Naval Base, Pearl Harbor, Temporary Storehouse & Gas Cylinder Storage, Avenue D, adjacent to east side of Facility No. 29, Pearl City, Honolulu County, HI

  5. 12. LOG FOUNDATION ELEMENTS OF THE SAWMILL ADJACENT TO THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. LOG FOUNDATION ELEMENTS OF THE SAWMILL ADJACENT TO THE CANAL, LOOKING EAST. BARREN AREA IN FOREGROUND IS DECOMPOSING SAWDUST. DIRT PILE IN BACKGROUND IS THE EDGE OF THE SUMMIT COUNTY LANDFILL. - Snake River Ditch, Headgate on north bank of Snake River, Dillon, Summit County, CO

  6. VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING RECREATION AREA ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING RECREATION AREA ON RIGHT, AND HOUSING AREA ON LEFT. VIEW FACING EAST/NORTHEAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  7. Pacific Currents: The Responses of U.S. Allies and Security Partners in East Asia to China’s Rise

    DTIC Science & Technology

    2008-01-01

    India, Australia, New Zealand, and Japan. Politically and militarily, it cooperates with India, Singapore, Malaysia , and Indonesia, as well as with...ASEAN countries are Indonesia, Malaysia , the Philippines, Thailand, and Vietnam. RAND MG736-2.10 China Six nationsa Subset of the sixb Five ASEAN...Indonesia, and Malaysia ) was higher than its return on investment in China—a change from the five preceding years, when return on investment in China

  8. Source apportionment of polycyclic aromatic hydrocarbons in surface sediment of mud areas in the East China Sea using diagnostic ratios and factor analysis.

    PubMed

    Deng, Wei; Li, Xian Guo; Li, Sheng Yong; Ma, Yan Yan; Zhang, Da Hai

    2013-05-15

    Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHs) have been quantified for surface sediments collected from the East China Sea (ECS). Our results showed that relatively high levels of PAHs and AHs occurred in both the inner and outer mud areas, while their concentrations at the control site were much lower. AHs for all samples were dominated by the unresolved complex mixture (UCM). Results from diagnostic ratios revealed that sedimentary PAHs were mainly originated from mixed combustion residues of biomass, coal, and petroleum. Combustion residues of petroleum and oil were responsible for the presence of high AHs concentrations. We also conducted factor analysis (FA) to further characterize the PAH and AH sources. Four factors were identified based on the loading of components and attributed to coal and wood combustion (Factor 1), traffic-related sources (Factor 2), petrogenic source (Factor 3) and natural gas combustion (Factor 4).

  9. Reconstruction of the East China Sea paleoenvironment at 16 ka by comparison of fossil and modern Faviidae corals from the Ryukyus, southwestern Japan

    NASA Astrophysics Data System (ADS)

    Mishima, M.; Kawahata, H.; Suzuki, A.; Inoue, M.; Okai, T.; Omura, A.

    2008-12-01

    We conducted paired measurements of the Sr/Ca ratio and oxygen and carbon stable isotopes of a fossil Faviidae coral specimen (MYK90), age 16 ka, collected from near Miyako Island, the Ryukyus, southwestern Japan. Our study aimed to reconstruct the paleoenvironment in the East China Sea at 16 ka by comparing the fossil sample with modern Faviidae corals. Our data with annual or longer time resolution may be very suitable for paleoceanographic reconstruction, although no general calibration method for Faviidae corals has been reported. Our calibration showed that the annual mean sea surface temperature was approximately 5°C lower and sea surface salinity (SSS) at the study site was locally higher at 16 ka than at present. Weak summer monsoon activity during the last glacial, which decreased summer precipitation over the Asian continent, and an enhanced winter monsoon, which may have led to more evaporation, likely contributed to the inferred high SSS at the study site.

  10. Morphological and molecular study of Longicollum pagrosomi Yamaguti, 1935 (Acanthocephala: Pomphorhynchidae) from the barred knifejaw Oplegnathus fasciatus (Temminck & Schlegel) (Perciformes: Oplegnathidae) in the East China Sea.

    PubMed

    Li, Liang; Yang, Yue; Zhang, Lu-Ping

    2017-02-01

    Longicollum pagrosomi Yamaguti, 1935 (Acanthocephala: Pomphorhynchidae) collected from the barred knifejaw Oplegnathus fasciatus (Temminck & Schlegel) (Perciformes: Oplegnathidae) in the East China Sea (off Zhoushan Islands) was studied using light and scanning electron microscopy. The SEM observations revealed for the first time the presence of about 28 well-developed sensory papillae arranged in a circle on the copulatory bursa. In addition, L. pagrosomi was characterised using molecular methods by sequencing of the internal transcribed spacer (ITS) of the ribosomal DNA based on the newly collected material. Longicollum pagrosomi is the first species of the genus with the ITS region sequenced for the purpose of species identification. These new morphological and molecular data contributed to a reliable and accurate specific identification and differentiation of species.

  11. Air quality impact of the coal-fired power plants in the northern passageway of the China West-East Power Transmission Project.

    PubMed

    Xue, Zhigang; Hao, Jiming; Chai, Fahe; Duan, Ning; Chen, Yizhen; Li, Jindan; Chen, Fu; Liu, Simei; Pu, Wenqing

    2005-12-01

    This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO2) and coarse particulate matter (PM10) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO2 and PM10 concentrations exceed 2 and 2.5 microg/m3, respectively. The maximum increases of the annually averaged SO2 and PM10 concentrations are 8.3 and 7.2 microg/m3, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO2 and PM10 concentrations fall to 4.9 and 4 microg/m3, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO2 and PM10, concentrations are, respectively, 6.3 and 5.6 microg/m3, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 microg/m3 after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.

  12. Differentiation of fecal Escherichia coli from human, livestock, and poultry sources by rep-PCR DNA fingerprinting on the shellfish culture area of East China Sea.

    PubMed

    Ma, Hong-Jia; Fu, Ling-Lin; Li, Jian-Rong

    2011-05-01

    The rep-PCR DNA fingerprinting performed with REP, BOX A1R, and (GTG)(5) primers was investigated as a way to differentiate between human, livestock, and poultry sources of fecal pollution on the area of Xiangshan Bay, East China Sea. Of the three methods, the BOX-PCR DNA fingerprints analyzed by jack-knife algorithm were revealed high rate of correct classification (RCC) with 91.30, 80.39, 89.39, 86.14, 93.24, 87.72, and 89.28% of human, cattle, swine, chicken, duck, sheep, and goose E. coli isolates classified into the correct host source, respectively. The average rate of correct classification (ARCC) of REP-, BOX-, and (GTG)(5)-PCR patterns was 79.88, 88.21, and 86.39%, respectively. Although the highest amount of bands in (GTG)(5)-PCR fingerprints could be observed, the discriminatory efficacy of BOX-PCR was superior to both REP- and (GTG)(5)-PCR. Moreover, the similarity of 459 isolates originated from shellfish and growing water was compared with fecal-obtained strains. The results showed that 92.4 and 96.2% E. coli strains isolated from midstream and downstream shellfish samples, respectively, had a ≥ 80% similarity with corresponding strains isolated from fecal samples. It was indicated that E. coli in feces could spread from human sewage or domestic farms to the surrounding shellfish culture water, and potentially affect the quality of shellfish. This work suggests that rep-PCR fingerprinting can be a promising genotypic tool applied in the shellfish growing water management on East China Sea for source identification of fecal pollution.

  13. Early Permian East-Ujimqin mafic-ultramafic and granitic rocks from the Xing'an-Mongolian Orogenic Belt, North China: Origin, chronology, and tectonic implications

    NASA Astrophysics Data System (ADS)

    Cheng, Yinhang; Teng, Xuejian; Li, Yanfeng; Li, Min; Zhang, Tianfu

    2014-12-01

    The East-Ujimqin complex, located north of the Erenhot-Hegenshan fault, North China, is composed of mafic-ultramafic and granitic rocks including peridotite, gabbro, alkali granite, and syenite. We investigated the tectonic setting, age, and anorogenic characteristics of the Xing'an-Mongolian Orogenic Belt (XMOB) through field investigation and microscopic and geochemical analyses of samples from the East-Ujimqin complex and LA-MC-ICP-MS zircon U-Pb dating of gabbro and alkali granite. Petrographic and geochemical studies of the complex indicate that this multiphase plutonic suite developed through a combination of fractional crystallization, assimilation processes, and magma mixing. The mafic-ultramafic rocks are alkaline and have within-plate geochemical characteristics, indicating anorogenic magmatism in an extensional setting and derivation from a mantle source. The mafic-ultramafic magmas triggered partial melting of the crust and generated the granitic rocks. The granitic rocks are alkali and metaluminous and have high Fe/(Fe + Mg) characteristics, all of which are common features of within-plate plutons. Zircon U-Pb geochronological dating of two samples of gabbro and alkali granite yielded ages of 280.8 ± 1.5 and 276.4 ± 0.7 Ma, placing them within the Early Permian. The zircon Hf isotopic data give inhomogeneous εHf(t) values of 8.2-14.7 for gabbroic zircons and extraordinary high εHf(t) values (8.9-12.5) for the alkali granite in magmatic zircons. Thus, we consider the East-Ujimqin mafic-ultramafic and granitic rocks to have been formed in an extensional tectonic setting caused by asthenospheric upwelling and lithospheric thinning. The sources of mafic-ultramafic and granitic rocks could be depleted garnet lherzolite mantle and juvenile continental lower crust, respectively. All the above indicate that an anorogenic magma event may have occurred in part of the XMOB during 280-276 Ma.

  14. Climate response and spatial-temporal model on the inter-annual change of winter temperature-salinity in the East China Sea

    NASA Astrophysics Data System (ADS)

    Yang, Jin-kun; Miao, Qing-sheng; Yang, Yang; Xu, Shan-shan

    2017-01-01

    Spatial distributions and time variation characteristics were analyzed using Rotated Empirical Orthogonal Function (REOF) and spectrum analysis methods using surface and bottom temperature and salinity data in February of 1976-2013 along 30°N section in the East China Sea. Result showed that temperature trends can be divided into western part and east part, salinity trend divided into western, middle and eastern part. The first mode of surface temperature presented a quasi-equilibrium trend and the range was higher in the near-shore than the offshores, first mode of bottom temperature presented a decreasing trend; surface salinity had a decreasing trend and the extent was higher in the near-shore than the offshores, the bottom salinity showed a decreasing trend in recent years. The temperature inter-annual variability related to El Niño closely; short-term shocks of salinity related to El Niño, and long-term changes had something to do with PDO.

  15. The Formation of Barrier Winds East of the Loess Plateau and Their Effects on Dispersion Conditions in the North China Plains

    NASA Astrophysics Data System (ADS)

    Hu, Xiao-Ming; Li, Xingliang; Xue, Ming; Wu, Dui; Fuentes, Jose D.

    2016-10-01

    The North China Plain (NCP) to the east of the Loess Plateau is one of the most heavily polluted areas in the world. Weak surface flow in the western part of the NCP exacerbates the air pollution in this region. Deceleration of low-level flow when approaching the Loess Plateau, together with enhanced roughness associated with large cities, were previously ascribed as the causes for low wind speeds in the NCP. Using numerical simulations with a one-layer dispersion model, we identify that dynamic modification of airflow by the Loess Plateau (not just simple deceleration due to mountain blocking) plays an important role in reducing the wind speed over the NCP. Dynamically-induced northerly barrier winds, superimposed on the prevailing southerly/south-easterly flow, reduce the wind speed in a 50-100 km wide region to the east of the Plateau, partially explaining the weak winds in the western part of the NCP. Poor dispersion conditions due to weak horizontal winds likely contribute to the accumulation of pollutants in this region.

  16. A unique Middle Pleistocene beech (Fagus)-rich deciduous broad-leaved forest in the Yangtze Delta Plain, East China: Its climatic and stratigraphic implication

    NASA Astrophysics Data System (ADS)

    Shu, Jun-wu; Wang, Wei-ming

    2012-08-01

    Pollen analysis of Middle Pleistocene sediments from the Yangtze Delta Plain provides a paleoecological reconstruction and has implications for stratigraphic correlation in East China. The pollen assemblage is characterized by high values of Fagus (16.8% on average), which is unusual because Fagus is generally present only sporadically in other lowland Quaternary pollen records from the region. In addition to Fagus, the assemblage has a rich diversity of broad-leaved deciduous trees, including Quercus, Ulmus, Carpinus/Ostrya, Juglans, Betula, and Liquidambar, as well as conifers, including Pinus, Picea, Abies, Larix, and Tsuga. Thus, the pollen flora suggests a broad-leaved deciduous forest mixed with abundant conifers, which developed under cooler and more humid conditions than present. The stable pollen sequence throughout the studied section suggests a stable environment. Beech forests also characterize the Middle Pleistocene of Taiwan and Japan, and thus may be a stratigraphic indicator of the Middle Pleistocene in East Asia. The Yangtze Delta Plain may have been an important refugium for the last survival of Fagus in the lowlands.

  17. Long-term variations of O3 at Ieodo Ocean Research Station in the East China Sea and the influence of Asian Outflows

    NASA Astrophysics Data System (ADS)

    Han, J.; Lee, M.; Shin, B.; Shim, J.

    2013-12-01

    Surface ozone was measured at Ieodo Ocean Research Station (IORS) from June 2003 to December 2010. IORS, a research tower of 40 m located in the East China Sea (32.07°N, 125.10°E), is equally distanced from South Korea, China, and Japan and therefore, it is an ideal place to observe Asian outflows without local effects. Compared with measurements at other remote sites in the North Pacific Ocean, the concentrations of ozone were noticeably higher at IORS, of which seasonal variation was in good agreement with those observed at remote stations with a distinct minimum (33 ppbv) in Jul-Aug and maximum (61 ppbv) in Mar-Apr. The 90th percentiles of ozone concentrations were 74-76 ppbv but the lowest (60 ppbv) during winter. It highlights the importance of photochemistry in ozone formation at IORS. This seasonal pattern was mainly due to different meteorological settings that determined the degree of anthropogenic influence from nearby lands. Ozone concentrations were well distinguished in six groups of air masses that were classified by the cluster analysis of backward trajectories. The marine air from the Pacific Ocean represents the relatively clean background air with the lowest ozone below 40 ppbv. In other seasons, the influence of Asian outflows was dominant with higher ozone concentrations over 55 ppbv. The monthly mean concentrations tended to increase until 2008 and slightly decreased afterwards.

  18. Distribution and mass inventory of mercury in sediment from the Yangtze River estuarine-inner shelf of the East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, Wenchuan; Hu, Limin; Lin, Tian; Li, Yuanyuan; Guo, Zhigang

    2017-01-01

    Mercury (Hg) was measured in 70 sediment samples from the Yangtze River estuarine-inner shelf of the East China Sea (ECS) to evaluate its occurrence, distribution, and deposition flux. Its concentrations were 10-92 ng/g with a mean of 46±17 ng/g. A decrease of Hg concentration with increasing distance offshore suggested a dominance of riverine input. The high levels of Hg observed at the southern inner shelf were partly due to the sorption affinity of fine-grained sediments. Hg concentration was significantly correlated with total organic carbon content and sediment grain size, implying that the nature of sedimentary organic matter and hydrodynamic forces could influence the Hg occurrence. A moderate correlation between Hg with high-molecular-weight polycyclic aromatic hydrocarbons in the YRE suggested that they shared a similar input pathway. The total deposition flux of Hg was estimated to be 52 t/y with a deposition rate of 6-120 ng/cm2 y, which indicated that the estuarine-inner shelf of the ECS was a major sink of Hg in the margins off China, and this area could play a significant role in the Hg biogeochemical cycle on a global scale.

  19. Distribution and sea-to-air flux of isoprene in the East China Sea and the South Yellow Sea during summer.

    PubMed

    Li, Jian-Long; Zhang, Hong-Hai; Yang, Gui-Peng

    2017-07-01

    Spatial distribution and sea-to-air flux of isoprene in the East China Sea and the South Yellow Sea in July 2013 were investigated. This study is the first to report the concentrations of isoprene in the China marginal seas. Isoprene concentrations in the surface seawater during summer ranged from 32.46 to 173.5 pM, with an average of 83.62 ± 29.22 pM. Distribution of isoprene in the study area was influenced by the diluted water from the Yangtze River, which stimulated higher in-situ phytoplankton production of isoprene rather than direct freshwater input. Variations in isoprene concentrations were found to be diurnal, with high values observed during daytime. A significant correlation was observed between isoprene and chlorophyll a in the study area. Relatively higher isoprene concentrations were recorded at stations where the phytoplankton biomass was dominated by Chaetoceros, Skeletonema, Pennate-nitzschia, and Thalassiosira. Positive correlation was observed between isoprene and methyl iodide. In addition, sea-to-air fluxes of isoprene approximately ranged from 22.17 nmol m(-2) d(-1)-537.2 nmol m(-2) d(-1), with an average of 161.5 ± 133.3 nmol m(-2) d(-1). These results indicate that the coastal and shelf areas may be important sources of atmospheric isoprene.

  20. [Polymorphism of hordein-coding loci in barley (Hordeum vulgare L.) populations from the countries of East Asia (China, Nepal, Pakistan, India)].

    PubMed

    Pomortsev, A A; Martynov, S P; Lialina, E V

    2012-08-01

    In this study, starch gel electrophoresis was used to examine polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd Floci in 201 accessions of barley landraces from China (including Tibet), Nepal, Pakistan, and India. Altogether, 50 alleles with the frequencies of 0.001-0.2269 were determined for the Hrd A locus, 65 alleles with the frequencies of 0.001-0.1612 were determined for the Hrd B locus, and five alleles with the frequencies of 0.001-0.4537 were determined for the Hrd Flocus. In barley populations from these countries, irregular distribution of alleles and allele frequencies was observed. Cluster analysis of the matrix of allele frequencies in populations from known sampling sites revealed cluster structure of local barley populations within each country. Local populations formed five differently sized clusters in Nepal, four such clusters in India, three clusters in China, and three clusters, in Pakistan. These results suggest that variation and allele frequency distribution of the hordein-coding loci in the countries of East Asia resulted from the introduction and spreading of barley forms through the husbandmen migrations.

  1. Characteristics and source appointment of atmospheric particulate mercury over East China Sea: Implication on the deposition of atmospheric particulate mercury in marine environment.

    PubMed

    Duan, Lian; Cheng, Na; Xiu, Guangli; Wang, Fujiang; Chen, Ying

    2017-02-12

    Total Suspended Particulate (TSP) samples were collected at Huaniao Island in northern East China Sea (ECS) from March 2012 to January 2013. Chemical analysis were conducted to measure the concentration of total particulate mercury (TPM) and speciated particulate mercury including HCl-soluble particulate mercury (HPM), elemental particulate mercury (EPM) and residual particulate mercury (RPM). The bromine (Br) and iodine (I) on particles were also detected. The mean concentration of TPM during the study period was 0.23 ± 0.15 ng m(-3), while the obviously seasonal variation was found that the concentrations of TPM in spring, summer, fall and winter were 0.34 ± 0.20 ng m(-3), 0.15 ± 0.03 ng m(-3), 0.15 ± 0.05 ng m(-3) and 0.27 ± 0.26 ng m(-3), respectively. The statistically strong correlation of bromine and iodine to HPM was only found in spring with r = 0.81 and 0.77 (p < 0.01), respectively. While the strongest correlations between EPM and bromine and iodine were found in winter with r = 0.92 (Br) and 0.96 (I) (p < 0.01), respectively. The clustered 72-h backward trajectories of different seasons and the whole sampling period were categorized into 4 groups. In spring, the clusters passed a long distance across the East China Sea and brought about low concentration of mercury due to the deposition of mercury over the sea. The cluster of air mass across the sea had low concentration of HPM in winter, which suggested that the oxidation of mercury in winter might be related to other oxidants. During the whole sampling period, the air mass from the north of China contributed to the higher concentration of TPM in Huaniao Island.

  2. Population Mobility in the People's Republic of China. Papers of the East-West Population Institute, No. 95.

    ERIC Educational Resources Information Center

    Goldstein, Sidney; Goldstein, Alice

    In attempts to forestall problems inherent in too-rapid urbanization, China has instituted a migration policy designed to strictly control changes in permanent residence from rural areas or small urban places to larger cities and to encourage the development of small cities and towns. The policy is enforced through the household registration…

  3. Meritocracy and the "Gaokao:" A Survey Study of Higher Education Selection and Socio-Economic Participation in East China

    ERIC Educational Resources Information Center

    Liu, Ye

    2013-01-01

    Meritocracy is a powerful ideology that was used by the Chinese Communist Party during China's transition to a market economy. With the "Gaokao" in particular, higher education selection became an ideal vehicle for the Party to associate itself with the ideology of meritocracy. This article investigates the extent to which higher…

  4. Potential linkages between the moisture variability in the northeastern Qaidam Basin, China, since 1800 and the East Asian summer monsoon as reflected by tree ring δ18O

    NASA Astrophysics Data System (ADS)

    Xu, Guobao; Chen, Tuo; Liu, Xiaohong; An, Wenling; Wang, Wenzhi; Yun, Hanbo

    2011-05-01

    We established the first annual resolution tree ring δ18O chronology of Qilian juniper (Sabina przewalskii Kom.) for the eastern margin of the Qaidam Basin, northwestern China. The mean tree ring cellulose δ18O in the study region (33.46‰ ± 0.99‰) was higher than that in the Qilian (28.7‰) and Helan Mountains (27.66‰), northwest China, and higher than the values in other published research (15.0‰ to 33.0‰), possibly as a result of the heavier δ18O in precipitation and the lower relative humidity (43%) during the growing season. The results of our simple correlation, bootstrap correlation, and response analyses showed that the cellulose δ18O was negatively and significantly correlated with relative humidity in July and August and that this correlation explained about 31.4% of the total variance in the moisture variability from 1954 to 2006. We also detected significant correlations among the Palmer drought severity index, the standard precipitation index, and the tree ring δ18O series. These analyses revealed that the summer relative humidity was the main limiting factor that affected δ18O values in the tree ring cellulose. Previous research indicates that the direct influence of the East Asian summer monsoon (EASM) reaches as far west as 100°E in China. However, our study revealed that the tree ring δ18O series was significantly correlated with the EASM index from 1873 to 1975, which means that the EASM influences moisture variability in the Qaidam Basin (farther west than 100°E) and that the tree ring δ18O chronology we obtained can be used as a proxy to study historical variability in the EASM.

  5. Over 100-year sedimentary record of polycyclic aromatic hydrocarbons (PAHs) and organochlorine compounds (OCs) in the continental shelf of the East China Sea.

    PubMed

    Cai, Yizhi; Wang, Xinhong; Wu, Yuling; Li, Yongyu; Ya, Miaolei

    2016-12-01

    Historical records of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were analyzed in two dated sediment cores (DH05 and DH11) collected from the continental shelf of the East China Sea (ECS) to investigate the influence of anthropogenic activities on marine sediment over the past century. The concentrations and fluxes of 15 PAHs were in the range of 28.6-96.5 ng g(-1) and 7.6-35.2 ng cm(-2) yr(-1) in DH05 (1920s-2009), 18.8-76.4 ng g(-1) and 13.9-30.9 ng cm(-2) yr(-1) in DH11 (1860s-2009). The sedimentary records of PAHs in the two cores generally reflected the economic development and energy consumption change in China. Identification of sources suggested that PAHs in ECS were predominantly from petrogenic origin and various combustion sources. A change of source from low- and moderate-temperature combustion to high-temperature combustion process was observed. Although a production ban of technical HCH and DDT was imposed in China in 1983, their sedimentary fluxes display increasing trends or strong rebounds from 1980s to 1990s as recorded in the core profiles. High proportions of DDD + DDE and γ-HCH suggested those OCPs mainly derived from early residuals. Temporal trends of PCBs presented relative high levels from 1970s to 1980s and high proportions of PCB congeners with 3-6 chlorines atoms indicated industrial sources.

  6. The peatlands developing history in the Sanjiang Plain, NE China, and its response to East Asian monsoon variation.

    PubMed

    Zhang, Zhenqing; Xing, Wei; Wang, Guoping; Tong, Shouzheng; Lv, Xianguo; Sun, Jimin

    2015-06-16

    Studying the peatlands accumulation and carbon (C) storage in monsoonal areas could provide useful insights into the response of C dynamics to climate variation in the geological past. Here, we integrated 40 well-dated peat/lake sediment cores to reveal the peatlands evolution history in the Sanjiang Plain and examine its links to East Asian monsoon variations during the Holocene. The results show that 80% peatlands in the Sanjiang Plain initiated after 4.7 ka (1 ka = 1000 cal yr BP), with the largest initiating frequency around 4.5 ka. The mean C accumulation rate of peatlands in the Sanjiang Plain exhibits a synchronous increase with the peatlands expansion during the Holocene. Such a peatlands expanding and C accumulating pattern corresponds well to the remarkable drying event subsequent to the Holocene monsoon maximum. We suggest that in addition to the locally topographic conditions, Holocene variations of East Asian summer monsoon (especially its associated precipitation) have played a critical role in driving the peatlands initiation and expansion in the Sanjiang Plain.

  7. Research of water resources allocation of South-to-North Water Diversion East Route Project in Jiangsu Province ,Eastern China

    NASA Astrophysics Data System (ADS)

    Zeng, C.

    2015-12-01

    Optimized allocation of water resources is the important means of solving regional water shortage and can improve the utilization of water resources. Water resources allocation in the large-scale water diversion project area is the current research focus. This research takes the east route of the South-to-North Water Transfer Project in Jiangsu province as the research area, based on the hydrological model, agricultural irrigation quota model, and water project scheduling model, a water resources allocation model was constructed. The research carried on generalized regional water supply network, simulated the water supply, water demand and water deficit in agriculture, industry, life, ecology and lock under the status quo and planning engineering conditions. According to the results, the east route of the South-to-North Water Transfer Project is helpful to improve regional water shortage situation. The results showed that pump output increase by 2.8 billion cubic meters of water. On the conditions of P = 95%, 75% and 50%, compared with the benchmark year, water demand increases slightly due to the need of social and economic development in planning years, and water supply increased significantly because of new diversion ability. Water deficit are greatly reduced by 74.9% especially in the commonly drought condition because of the new project operation and optimized allocation of water resources.

  8. Cross-shelf transport of terrestrial Al enhanced by the transition of northeasterly to southwesterly monsoon wind over the East China Sea

    NASA Astrophysics Data System (ADS)

    Ren, Jing-Ling; Xuan, Ji-Liang; Wang, Zhao-Wei; Huang, Daji; Zhang, Jing

    2015-07-01

    Aluminum (Al) is one of the key parameters of GEOTRACES. In spring 2011, we examined the distribution of dissolved Al in the East China Sea (ECS) to assess the potential passage of coastal water across the shelf to the western Pacific. Measurement of dissolved Al in coastal, shelf, and shelf break waters indicated decreasing concentrations with distance from the coast. However, the northward increase of dissolved Al in the upper 100 m along the shelf break transect, corresponding to the northward flow of Kuroshio Water along the Okinawa Trough from the north of Taiwan to the Tokara strait, indicates contributions of terrestrial material. The presence of an Al plume indicated cross-shelf transport at the subsurface at a potential density of 23.3-24.0 kg/m3. This plume originates from the near-bottom layer along the coast off Zhejiang and Fujian Provinces, and first moves southeastward (to the north of Taiwan) and then northeastward (to shelf break with export at 29°N, 127°E). We calculated the cross-shelf fluxes of water and dissolved Al based on simulation results of the 3-D Massachusetts Institute of Technology general circulation model (MITgcm). The calculated cross-shelf fluxes of Al at the subsurface layer indicate that the ECS is highly efficient in pumping Al-rich coastal waters northward to the Japan Sea/East Sea and/or eastward into the western Pacific. We also identified an important role of the monsoon, with a change from northeasterly wind to southwesterly wind in spring, on the cross-shelf transport of Al by use of numerical tracer experiments.

  9. Distribution and bioaccumulation of heavy metals in marine organisms in east and west Guangdong coastal regions, South China.

    PubMed

    Zhang, Ling; Shi, Zhen; Jiang, Zhijian; Zhang, Jingping; Wang, Fei; Huang, Xiaoping

    2015-12-30

    Heavy metal (Cu, Pb, Zn, Cr, Cd, As) concentrations, distribution and bioaccumulation were studied in marine organisms in Guangdong coastal regions. Heavy metal concentrations and distribution in organisms showed characteristics according to areas and species. Heavy metal concentrations in most organisms were higher in west than in east, tightly related to the local industry structure and the disequilibrium of metal discharge. Generally, high heavy metal concentrations were detected in molluscs and low concentrations were detected in fish. Bioaccumulation factor was used to assess the accumulation level of marine organisms to heavy metals, of which Cd, Cu and As were the most accumulated elements. Accumulation abilities to heavy metals varied among organism species, such as Distorsio reticulate accumulating Cu, Zn, Cd, As, Loligo beka Sasaki accumulating Pb, Cu, Cr, and Turritella bacillum Kiener accumulating Zn, Cd, As. By comparison, Johnius belengeri, Argyrosomus argentatus, Cynoglossus sinicus Wu had relatively low accumulation abilities.

  10. Records of the paleoclimate during the fast transgression period (13 ka BP-8 ka BP) from the mud area on the inner shelf of the East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, S.

    2015-12-01

    A 35.30m-long core (MZ02) recovered from a water depth of 32.4m from the inner shelf mud deposit of the East China Sea was analyzed for sedimentary characteristics, color reflectance, clay mineral, and element geochemistry components as well as by AMS 14C dating to research the sedimentation rate, sediment provenance and paleocwan mountainous river and clay fralimate evolution during the fast transgression period in the study area. Rare earth element and clay mineral proxies indicated that the mixed provenance sediment accumulated in the foreshore-nearshore region at the beginning of the fast transgression period, with a higher sedimentation rate of 5.58m/ka. While from 9800-9500 a B.P., the sedimentation rate keep lower about 1.73m/ka, and the sediment provenance changed obviously, silt fraction were apt to Taiction prone to be transported from the Yangtze River. Multiple proxy system including sediment redness (a*), chemical index of alteration (CIA), clay mineral proxy (smectite/kaolinite), major and trace element proxy (CaO/MgO, Ba/Sr) also showed a good paleoclimate record during the fast transgression period, which could be divided into three units. All the proxies changed little during Unit I (13-11.3ka B.P.) and revealed the climate kept in a relative stable level. Obvious fluctuation happened in Unit II (11.3-10.1ka B.P.) and the temperature kept decreasing more than 1ka till the Younger Dryas event, showed a well regional response to global climate changes. While continuous warming trend resumed again in Unit III (10.1-8 ka B.P.), which may be the signal for Holocene warm period. In addition, we also found significant 80yr, 89yr and 100yr cycles in our CIA, CaO/MgO and Ba/Sr records that imply a possible solar influence on the regional climate changes during the fast transgression period. Keywords: East China Sea, provenance, transgression, mud deposit, late Pleistocene, paleoclimate

  11. Applying Earth Observation Data to agriculture risk management: a public-private collaboration to develop drought maps in North-East China

    NASA Astrophysics Data System (ADS)

    Surminski, S.; Holt Andersen, B.; Hohl, R.; Andersen, S.

    2012-04-01

    Earth Observation Data (EO) can improve climate risk assessment particularly in developing countries where densities of weather stations are low. Access to data that reflects exposure to weather and climate risks is a key condition for any successful risk management approach. This is of particular importance in the context of agriculture and drought risk, where historical data sets, accurate current data about crop growth and weather conditions, as well as information about potential future changes based on climate projections and socio-economic factors are all relevant, but often not available to stakeholders. Efforts to overcome these challenges in using EO data have so far been predominantly focused on developed countries, where satellite-derived Normalized Difference Vegetation Indexes (NDVI) and the MERIS Global Vegetation Indexes (MGVI), are already used within the agricultural sector for assessing and managing crop risks and to parameterize crop yields. This paper assesses how public-private collaboration can foster the application of these data techniques. The findings are based on a pilot project in North-East China where severe droughts frequently impact the country's largest corn and soybeans areas. With support from the European Space Agency (ESA), a consortium of meteorological experts, mapping firms and (re)insurance experts has worked to explore the potential use and value of EO data for managing crop risk and assessing exposure to drought for four provinces in North-East China (Heilongjiang, Jilin, Inner Mongolia and Liaoning). Combining NDVI and MGVI data with meteorological observations to help alleviate shortcomings of NDVI specific to crop types and region has resulted in the development of new drought maps for the time 2000-2011 in digital format at a high resolution (1x1 km). The observed benefits of this data application range from improved risk management to cost effective drought monitoring and claims verification for insurance purposes

  12. Petrology and geochemistry of Cenozoic intra-plate basalts in east-central China: Constraints on recycling of an oceanic slab in the source region

    NASA Astrophysics Data System (ADS)

    Li, Yan-Qing; Ma, Chang-Qian; Robinson, Paul T.

    2016-10-01

    Cenozoic mafic rocks in Jiangsu and Anhui Provinces, east-central China are chiefly basanites and alkali olivine basalts with subordinate tholeiites, which were erupted in three stages; Paleogene, Neogene and Quaternary. The rocks become increasingly alkaline as they become younger. On a primitive mantle-normalized multi-element plot, these lavas exhibit typical OIB-like trace element patterns, including enrichment in most incompatible elements (LILE and HFSE) and negative K and Pb anomalies. The compositions of the mafic rocks indicate that they were derived from a mantle source mainly containing clinopyroxene and garnet, most probably a mixture of pyroxenite/eclogite and peridotite. A mineral equilibrium projection shows that all the mafic magmas were produced at pressures of 3-4 GPa, implying an asthenospheric origin. Their positive Ba and Sr anomalies and relatively high 87Sr/86Sr ratios suggest derivation from an EM1-type mantle source. However, poor correlations between 87Sr/86Sr and 143Nd/144Nd indicate an isotopically heterogeneous source for the magmas, including DMM, EM1 and EM2, representing mantle peridotite, recycled ancient oceanic crust and seafloor sedimentary rocks, respectively. Variable correlations between 87Sr/86Sr and 143Nd/144Nd ratios, CaO-MgO contents and Eu/Eu* and Ce/Ce* anomalies with rock type imply that marine sediments (plus variable amounts of oceanic crust) and peridotites were the dominant source lithologies of the basanites, whereas recycled oceanic crust (pyroxenite/eclogite) was the main source of the weakly alkaline basalts. This hypothesis is supported by seismic tomographic images of the mantle beneath the region, which show the presence of a stagnant subducted slab in the mantle transition zone. Thus, we propose a petrological model in which a hybrid magma column originated from the mantle transition zone and assimilated some of the overlying peridotite during upwelling, to become the parental magmas of these mafic rocks

  13. The tectonics of the western Ordos Plateau, Ningxia, China: Slip rates on the Luoshan and East Helanshan Faults

    NASA Astrophysics Data System (ADS)

    Middleton, Timothy A.; Walker, Richard T.; Rood, Dylan H.; Rhodes, Edward J.; Parsons, Barry; Lei, Qiyun; Elliott, John R.; Ren, Zhikun; Zhou, Yu

    2016-11-01

    Analysis of the locus, style, and rate of faulting is fundamental to understanding the kinematics of continental deformation. The Ordos Plateau lies to the northeast of Tibet, within the India-Eurasia collision zone. Previous studies have suggested that it behaves rigidly and rotates anticlockwise within a large-scale zone of ENE-WSW left-lateral shearing. For this rotation to be accommodated, the eastern and western margins of the Ordos Plateau should be undergoing right-lateral shearing and yet the dominant faulting style appears to be extensional. We focus specifically on the kinematics of the faults bounding the western margin of the Ordos Plateau and make new slip rate estimates for two of the major faults in the region: the right-lateral strike-slip Luoshan Fault and the normal-slip East Helanshan Fault. We use a combination of infrared stimulated luminescence dating of offset landforms with high-resolution imagery and topography from the Pleiades satellites to determine an average right-lateral slip rate of 4.3 ± 0.4 mm/a (1σ uncertainty) on the Luoshan Fault. Similarly, we use 10Be exposure dating to determine a vertical throw rate on the East Helanshan Fault of <0.6 ± 0.1 mm/a, corresponding to an extension rate of <0.7 ± 0.1 mm/a (1σ uncertainty). Both of these results agree well with slip rates determined from the latest campaign GPS data. We therefore conclude that right-lateral shearing is the dominant motion occurring in the western Ordos region, supporting a kinematic model of large-scale anticlockwise rotation of the whole Ordos Plateau.

  14. Substantial Underestimation of Post-harvest Burning Emissions in East China as Seen by Multi-species Space Observations

    NASA Astrophysics Data System (ADS)

    Stavrakou, T.; Muller, J. F.; Bauwens, M.; De Smedt, I.; Lerot, C.; Van Roozendael, M.

    2015-12-01

    Crop residue burning is an important contributor to global biomass burning. In the North China Plain, one of the largest and densely populated world plains, post-harvest crop burning is a common agricultural management practice, allowing for land clearing from residual straw and preparation for the subsequent crop cultivation. The most extensive crop fires occur in the North China Plain in June after the winter wheat comes to maturity, and have been blamed for spikes in air pollution leading to serious health problems. Estimating harvest season burning emissions is therefore of primary importance to assess air quality and define best policies for its improvement in this sensitive region. Bottom-up approaches, either based on crop production and emission factors, or on satellite burned area and fire radiative power products, have been adopted so far, however, these methods crucially depend, among other assumptions, on the satellite skill to detect small fires, and could lead to underestimation of the actual emissions. The flux inversion of atmospheric observations is an alternative, independent approach for inferring the emissions from crop fires. Satellite column observations of formaldehyde (HCHO) exhibit a strong peak over the North China Plain in June, resulting from enhanced pyrogenic emissions of a large suite of volatile organic compounds (VOCs), precursors of HCHO. We use vertical columns of formaldehyde retrieved from the OMI instrument between 2005 and 2012 as constraints in an adjoint inversion scheme built on IMAGESv2 CTM, and perform the optimization of biogenic, pyrogenic, and anthropogenic emission parameters at the model resolution. We investigate the interannual variability of the top-down source, quantify its importance for the atmospheric composition on the regional scale, and explore its uncertainties. The OMI-based crop burning source is compared with the corresponding anthropogenic flux in the North China Plain, and is evaluated against HCHO

  15. Mid-Holocene variability of the East Asian monsoon based on bulk organic δ13C and C/N records from the Pearl River estuary, southern China

    NASA Astrophysics Data System (ADS)

    Yu, F.; Zong, Y.; Lloyd, J. M.; Leng, M. J.; Switzer, A. D.; Yim, W. W.; Huang, G.

    2012-12-01

    Understanding the mid-Holocene dynamics of the East Asian monsoon (EAM) is integral to modelling the Holocene development of the global climate system (Webster et al., 1998). Thus the mid-Holocene EAM history was reconstructed using bulk organic carbon isotopes (δ13C), total carbon to total nitrogen (C/N) ratios and total organic carbon (TOC) from a sediment core (UV1), at a mean resolution of 7-10 years, from the Pearl River estuary, southern China. Sedimentary δ13C, C/N and TOC from the Pearl River estuary is a good indicator of changes in monsoonal precipitation strength (Zong et al., 2006; Yang et al., 2010; Yu et al., 2010), eg sediments buried during a period of high precipitation exhibit a high proportion of terrigenous sediments, and have low δ13C and high C/N, and vice versa (Yu et al., 2010). Results suggest a general decreasing trend in monsoonal precipitation from 6650 to 2215 cal yr BP because of the weakening Northern Hemisphere insolation most likely related to the current precession circle (An, 2000). Superimposed on this trend are apparent dry-wet oscillations at centennial to millennial timescales most likely in response to solar activity. Mismatch between δ13C and results from the Dongge Cave in southern China at millennial-timescale oscillations (Wang et al., 2005), may indicate that the δ13C from the Pearl River estuary reveals changes in precipitation in a broader area than the δ18O from Dongge Cave does. Reference An Z (2000) The history and variability of the East Asian paleomonsoon climate. Quaternary Science Reviews 19: 171-187. Wang Y, Cheng H, Edwards RL, He Y, Kong X, An Z, Wu J, Kelly MJ, Dykoski CA and Li X (2005) The Holocene Asian Monsoon: Links to Solar Changes and North Atlantic Climate. Science 308: 854-857. Webster PJ, Magaña VO, Palmer TN, Shukla J and Tomas RA (1998) Monsoons: Processes, predictability, and the prospects for prediction. Journal of Geophysical Research 103(C7): 14451-14510. Yang S, Tang M, Yim WWS, Zong

  16. Mid-Holocene variability of the East Asian monsoon based on bulk organic δ13C and C/N records from the Pearl River estuary, southern China

    NASA Astrophysics Data System (ADS)

    Yu, F.; Lloyd, J. M.; Zong, Y.; Leng, M. J.; Switzer, A. D.; Yim, W. W.; Huang, G.

    2010-12-01

    Understanding the mid-Holocene dynamics of the East Asian monsoon (EAM) is integral to modelling the Holocene development of the global climate system (Webster et al., 1998). Thus the mid-Holocene EAM history was reconstructed using bulk organic carbon isotopes (δ13C), total carbon to total nitrogen (C/N) ratios and total organic carbon (TOC) from a sediment core (UV1), at a mean resolution of 10 years, from the Pearl River estuary, southern China. Sedimentary δ13C, C/N and TOC from the Pearl River estuary is a good indicator of changes in monsoonal precipitation strength (Zong et al., 2006; Yang et al., 2010), eg sediments buried during a period of high precipitation exhibit a high proportion of terrigenous sediments, and have low δ13C and high C/N, and vice versa (Yu et al., 2010). Results suggest a general decreasing trend in monsoonal precipitation from 6650-2215 cal yr BP due to the weakening insolation over northern hemisphere most likely related to the current precession circle (An, 2000). Superimposed on this trend are apparent dry-wet oscillations at centennial to millennial timescales most likely in response to solar activity. Mismatch between δ13C and results from the Dongge Cave in southern China at millennial-timescale oscillations (Wang et al., 2005), may indicate that the δ13C from the Pearl River estuary reveals changes in precipitation in a broader area than the δ18O from Dongge Cave does. Reference An Z (2000) The history and variability of the East Asian paleomonsoon climate. Quaternary Science Reviews 19: 171-187. Wang Y, Cheng H, Edwards RL, He Y, Kong X, An Z, Wu J, Kelly MJ, Dykoski CA and Li X (2005) The Holocene Asian Monsoon: Links to Solar Changes and North Atlantic Climate. Science 308: 854-857. Webster PJ, Magaña VO, Palmer TN, Shukla J and Tomas RA (1998) Monsoons: Processes, predictability, and the prospects for prediction. Journal of Geophysical Research 103(C7): 14451-14510. Yang S, Tang M, Yim WWS, Zong Y, Huang G, Switzer

  17. [Ecological niche breadth and niche overlap of dominant species of fish assemblage in Yangtze river estuary and its adjacent waters].

    PubMed

    Li, Xian-sen; Yu, Zhen-hai; Sun, Shan; Jin, Xian-shi

    2013-08-01

    Based on the fishery resources data from the bottom trawl surveys conducted on the R/V Beidou in the Yangtze River estuary and its adjacent waters in June, August and October of 2006, the index of relative importance (IRI) was measured to determine the dominant species of fish assemblage, and the niche indicators and their seasonal variations of the dominant species were analyzed. A total of 10 dominant species in the 3 survey cruises were recorded, which were divided into two groups by the Bray-curtis similarity clustering and non-metric multidimensional scaling (MDS) analysis, with a significant seasonal variation of niche breadth and niche overlap. One group included Engraulis japonicus, Champsodon capensis, and Acropoma japonicum, whose niche breadth and niche overlap were larger in summer than in autumn, with a migration from the Yangtze River estuary and its adjacent waters to outer deeper waters, while the other group included Trichiurus haumela, Chaeturichthys stigmatias, Apogon lineatus, Larimichthys polyactis, Psenopsis anomala, Argyrosomus argentatus, and Benthosema pterotum, whose niche breadth and niche overlap were larger in autumn than in summer, with a reverse migration from southern Yellow Sea and northern East China Sea to the Yangtze River estuary and its adjacent waters. The different migration direction of the two groups was related to their ecological habits and environmental factors.

  18. Impacts of sea-level change on human activity at the early Neolithic forager/cultivator site, Kuahuqiao on the east coast of China

    NASA Astrophysics Data System (ADS)

    Zong, Yongqiang; Innes, James; Chen, Zhongyuan; Chen, Chun; Wang, Zhanghua; Wang, Hui

    2010-05-01

    The date and location of the adoption of rice cultivation by foraging cultures in China is of considerable current interest but its understanding is hampered by a lack of information regarding its palaeoenvironmental context. We present detailed multi-proxy palaeoecological research at the earliest-dated site of rice cultivation in the coastal area of east China which has revealed the precise environmental setting of this early Neolithic settlement and its incipient cultivation at c. 7750 cal. BP. Regional and local environmental changes governed the character of the site and the duration of human activity. The rise in relative sea level up to 8000 cal. BP prompted the development of coastal wetland environments at the head of the Hangzhou Bay. A short period of stable sea level allowed natural hydrological succession and terrestrialisation of the site changing from a brackish/freshwater lake to a freshwater marsh/alder carr, which attracted Neolithic foragers to settle and take advantage of the plentiful food resources present in the wetland, wild rice in particular. After a fire clearance of an alder scrub that prepared the ground for settlement, the Kuahuqiao people maintained a reedswamp-type wet grassland in which rice was grown. As relative sea level rose again around 7600-7500 cal. BP, artificial bunding was used to retain nutrient rich water and prevent tidal flooding to provide rice with the consistent water regime it requires. Such bunding resulted in blockage of water which promoted the growth of aquatic plants such as Cattail. Cropping of Cattail stands may have formed part of the subsistence base. Thesite was overwhelmed by marine inundation around 7400-7200 cal. BP as relative sea level rose rapidly for a couple of meters, after which rice cultivation spread to Neolithic sites of Hemudu type elsewhere in the coastal lowlands.

  19. 2-year study of chemical composition of bulk deposition in a South China coastal city: comparison with East Asian cities

    SciTech Connect

    K.M. Wai; P.A. Tanner; C.W.F. Tam

    2005-09-01

    Using the emission strengths of the precursor gases, the nature of soil in China, the ventilation power and half value rainout region length, the nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Ca{sup 2+}, and NH{sub 4}{sup +} concentrations, and pH of rainwater at Hong Kong and other cities of China and Japan are compared and rationalized. The chemical composition of Hong Kong bulk deposition from 1998 to 2000 is taken from the collection and analysis of 156 daily samples. The volume-weighted average (VWA) pH is 4.2 over the whole study period. Nonsea salt- (nss-) sulfate is the most abundant species in the samples, and the pH mostly depended upon the concentrations of the major species nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Ca{sup 2+}, and NH{sub 4}{sup +}. All species concentrations show higher levels in the cold season (especially NO{sub 3}- and Ca{sup 2+}), which indicates the dominant dilution effects in the warm season due to heavy rainfall and the influence of the continental outflow of pollutants during the cold season. For Hong Kong bulk deposition, the VWA pH is slightly lower in the cold season, and there is a slight decrease in VWA pH over the period from 1994 to 2000. The impact of acid rain in Hong Kong is briefly discussed. 36 refs., 3 figs., 5 tabs.

  20. Predictors on Delay of Initial Health-Seeking in New Pulmonary Tuberculosis Cases among Migrants Population in East China

    PubMed Central

    Li, Xinxu; Jiang, Shiwen; Li, Xue; Mei, Jian; Zhong, Qiu; Xu, Weiguo; Li, Jun; Li, Weibin; Liu, Xiaoqiu; Zhang, Hui; Wang, Lixia

    2012-01-01

    Objectives To determine the length of delay in initial health-seeking in new pulmonary tuberculosis (PTB) cases among migrant population in the eastern part of China, and factors associated with it. Methods A cross-sectional study was conducted using a structured questionnaire in six counties in Shanghai, Guangdong and Jiangsu from May to October, 2008, to estimate the extent and factors responsible for delayed initial health-seeking of the new PTB cases. The interval between self-reported onset of TB symptoms and date of first attendance at any medical institution was determined. More than the median duration was defined as delayed health-seeking. Results A total of 323 new migrant PTB patients participated in the study. Only 6.5% had medical insurance. The median and mean durations to initial health-seeking were respectively 10 and 31 days. There was no significant association between socio-demographic factors and delayed initial health-seeking. Average monthly working days >24 (AOR, 1.61; 95% CI, 1.03–2.51), and hemoptysis or bloody sputum (AOR, 0.48; 95% CI, 0.28–0.85) were significantly associated with delayed initial health-seeking. Conclusions Interventions to improve health seeking behavior among the migrant population in China must focus on strengthening their labor, medical security and health education. PMID:22384123

  1. Genotype I of hepatitis B virus was found in east Xishuangbanna, China and molecular dynamics of HBV/I.

    PubMed

    Shen, T; Yan, X M; Liu, H X; Zhang, B X; Li, L; Zhang, J P; Wang, J L; Xiao, C J

    2015-01-01

    There is a dearth of data about the prevalence of hepatitis B virus (HBV) infection in Mengla, China; and no detailed analysis of the molecular evolution of genotype I in Asia. In this study, 909 serum samples from ethnic minority people in China were obtained. Serological assay and HBV S-gene amplification were carried out, and phylogenetic and evolutionary dynamics analysis of 62 HBV/I S-gene was performed. On this survey, 153 individuals were tested HBsAg-positive. Genotypes of S-gene were classified into three groups: C, B and I. Under the strict model and the relax model, the estimated evolutionary rates for HBV/I were 3.74 × 10(-4) and 6.93 × 10(-4) substitution/site/year, respectively. However, when the geographic origin was taken into account, the mean substitution rates were increased. Estimated time to most recent ancestor of genotype I varied from ~30 to ~70 years ago. The Bayesian sky plot showed a rapid spread of HBV/I at the end of 1980s. Peculiar nucleotides distributed were observed in the subgenotype I1/I2. In conclusion, higher prevalence of HBV infection was observed in Mengla county. Multifactors like timescale and spatial locations should be integrated to provide a better interpretation of the HBV/I evolutionary history in the region.

  2. DEPSCoR FY 99: Use of Stochastic Modeling of Stratigraphic Relationships in High Resolution Seismic Reflection Data for Prediction of the Distribution of Acoustic and Geotechnical Property Variability in Near Surface Sediments on the East China Sea Continental Margin

    DTIC Science & Technology

    2016-06-13

    Distribution of Acoustic and Geotechnical Property Variability in Near Surface Sediments on the East China Sea Continental Margin Louis R. Bartek Department of...of vertical and horizontal distribution of seismic facies (and therefore geotechnical and acoustic properties) • Determine the minimum data required...Resolution Seismic Reflection Data for Prediction of the Distribution of Acoustic and Geotechnical Property Variability in Near Surface Sediments on the

  3. Geochemical background and ecological risk of heavy metals in surface sediments from the west Zhoushan Fishing Ground of East China Sea.

    PubMed

    Xu, Gang; Liu, Jian; Pei, Shaofeng; Hu, Gang; Kong, Xianghuai

    2015-12-01

    Surface sediment grain size as well as the spatial distribution, pollution status, and source identification of heavy metals in the west Zhoushan Fishing Ground (ZFG) of the East China Sea were analyzed to study the geochemical background concentrations of heavy metals and to assess their potential ecological risk. Our results show that surface sediments in the eastern part of study area were mainly composed of sand-sized components. Spatial distributions of heavy metals were mainly controlled by grain size and terrigenous materials, and their concentrations in the coarsest grain sediments formed primarily during the Holocene transgressive period could represent the element background values of our study area. Contamination factor suggests that there was no pollution of Pb, Zn, and Cr generally in our study area and slight pollution of Cu, Cd, and As (especially Cu) at some stations. In addition, ecological harm coefficient indicates that the ecological risk of each heavy metal, except for Cd, at two stations was low as well. These results are consistent with the pollution load index and ecological risk index, which suggest both the overall level of pollution and the overall ecological risk of six studied metals in sediment were relatively low in our study area. Enrichment factor indicates that the heavy metals came mostly from the natural source. Summarily, the quality level of sediment in our study area was relatively good, and heavy metals in sediments could not exert threat to aquatic lives in the ZFG until now.

  4. A Carbon Cycle Model for the Social-Ecological Process in Coastal Wetland: A Case Study on Gouqi Island, East China.

    PubMed

    Li, Yanxia; Xiong, Lihu; Zhu, Wenjia

    2017-01-01

    Coastal wetlands offer many important ecosystem services both in natural and in social systems. How to simultaneously decrease the destructive effects flowing from human activities and maintaining the sustainability of regional wetland ecosystems are an important issue for coastal wetlands zones. We use carbon credits as the basis for regional sustainable developing policy-making. With the case of Gouqi Island, a typical coastal wetlands zone that locates in the East China Sea, a carbon cycle model was developed to illustrate the complex social-ecological processes. Carbon-related processes in natural ecosystem, primary industry, secondary industry, tertiary industry, and residents on the island were identified in the model. The model showed that 36780 tons of carbon is released to atmosphere with the form of CO2, and 51240 tons of carbon is captured by the ecosystem in 2014 and the three major resources of carbon emission are transportation and tourism development and seawater desalination. Based on the carbon-related processes and carbon balance, we proposed suggestions on the sustainable development strategy of Gouqi Island as coastal wetlands zone.

  5. Investigating the effects of point source and nonpoint source pollution on the water quality of the East River (Dongjiang) in South China

    USGS Publications Warehouse

    Wu, Yiping; Chen, Ji

    2013-01-01

    Understanding the physical processes of point source (PS) and nonpoint source (NPS) pollution is critical to evaluate river water quality and identify major pollutant sources in a watershed. In this study, we used the physically-based hydrological/water quality model, Soil and Water Assessment Tool, to investigate the influence of PS and NPS pollution on the water quality of the East River (Dongjiang in Chinese) in southern China. Our results indicate that NPS pollution was the dominant contribution (>94%) to nutrient loads except for mineral phosphorus (50%). A comprehensive Water Quality Index (WQI) computed using eight key water quality variables demonstrates that water quality is better upstream than downstream despite the higher level of ammonium nitrogen found in upstream waters. Also, the temporal (seasonal) and spatial distributions of nutrient loads clearly indicate the critical time period (from late dry season to early wet season) and pollution source areas within the basin (middle and downstream agricultural lands), which resource managers can use to accomplish substantial reduction of NPS pollutant loadings. Overall, this study helps our understanding of the relationship between human activities and pollutant loads and further contributes to decision support for local watershed managers to protect water quality in this region. In particular, the methods presented such as integrating WQI with watershed modeling and identifying the critical time period and pollutions source areas can be valuable for other researchers worldwide.

  6. Phytoplankton diversity in the East China Sea and Yellow Sea measured by PCR-DGGE and its relationships with environmental factors

    NASA Astrophysics Data System (ADS)

    Sun, Jing; Yu, Zhigang; Gao, Yahui; Zhou, Qianqian; Zhen, Yu; Chen, Hongtao; Zhao, Liyuan; Yao, Qingzhen; Mi, Tiezhu

    2010-03-01

    Relationships between phytoplankton community composition and environmental variables in the East China Sea (ECS) and Yellow Sea (YS) were investigated using geochemical and molecular microbiology methods. The diversity of phytoplankton was characterized using cultivation-independent PCR-based denaturing gradient gel electrophoresis (DGGE). Groups resulting from unweighted pair-group method with arithmetic averages clustering of the DGGE profiles showed good consistency with the eco-environmental characteristics of the sea area they belonged to. Additionally, the clustering results based on DGGE fingerprinting and those based on morphological compositions were practically identical. The relationship of phytoplankton diversity to environmental factors was statistically analyzed. Temperature, dissolved inorganic nitrogen (DIN), and silicate-Si were found significantly related to the phytoplankton community composition. Canonical correspondence analysis (CCA) was performed to reveal the relationship between community composition and these three environmental factors. Generally, values of the ECS are clearly separated from those of the YS in the CCA biplot, due to mainly the effect of temperature and DIN.

  7. Measurements of volatile organic compounds in the middle of Central East China during Mount Tai Experiment 2006 (MTX2006): observation of regional background and impact of biomass burning

    NASA Astrophysics Data System (ADS)

    Suthawaree, J.; Kato, S.; Okuzawa, K.; Kanaya, Y.; Pochanart, P.; Akimoto, H.; Wang, Z.; Kajii, Y.

    2009-08-01

    The measurement of volatile organic compounds (VOCs) was carried out at the summit of Mount Tai, located in the center of the Central East China (CEC) region, in June 2006 as part of the Mount Tai Experiment 2006 (MTX2006), which focused on the ozone and aerosol chemistry in the region. Temporal variations of simple VOCs between June 2 and June 28 revealed the characteristics of an aged air mass with minimum local influence. A comparison of VOCs observed at Mount Tai with other Chinese sites revealed relatively similar VOC levels to remote sites and, as expected, a lower level compared to more polluted sites. However, relatively high acetylene and benzene levels at Mount Tai were evidently indicated from comparison with normalized VOC profile by ethane suggested for Beijing. Owing to a shift in boundary layer height, we observed considerable differences between daytime and nighttime VOC concentrations. This suggests that the site has a very useful characteristic of being able to measure regional polluted air and the free troposphere regional background air quality. Influence of emissions from biomass burning in the region was evidently found to be extensive during the first half of the campaign (2-15 June), using fire spot data coupling with backward trajectory analysis. Agricultural residue burning was suggested as the primary source of emissions elucidated by the slope of the correlation plot between CH3Cl and CO obtained during the first half of the campaign.

  8. Measurements of volatile organic compounds in the middle of Central East China during Mount Tai Experiment 2006 (MTX2006): observation of regional background and impact of biomass burning

    NASA Astrophysics Data System (ADS)

    Suthawaree, J.; Kato, S.; Okuzawa, K.; Kanaya, Y.; Pochanart, P.; Akimoto, H.; Wang, Z.; Kajii, Y.

    2010-02-01

    The measurement of volatile organic compounds (VOCs) was carried out at the summit of Mount Tai, located in the center of the Central East China (CEC) region, in June 2006 as part of the Mount Tai Experiment 2006 (MTX2006), which focused on the ozone and aerosol chemistry in the region. Temporal variations of simple VOCs between 2 June and 28 June revealed the characteristics of an aged air mass with minimum local influence. A comparison of VOCs observed at Mount Tai with other Chinese sites revealed relatively similar VOC levels to remote sites and, as expected, a lower level compared to more polluted sites. However, relatively high acetylene and benzene levels at Mount Tai were evidently indicated from comparison with normalized VOC profile by ethane suggested for Beijing. Owing to a shift in boundary layer height, we observed considerable differences between daytime and nighttime VOC mixing ratios. This suggests that the site potentially has a very useful characteristic of being able to measure regional polluted air and the free troposphere regional background air quality. Influence of emissions from biomass burning in the region was evidently found to be extensive during the first half of the campaign (2-15 June), using fire spot data coupling with backward trajectory analysis. Agricultural residue burning was suggested as the primary source of emissions elucidated by the slope of the correlation plot between CH3Cl and CO obtained during the first half of the campaign.

  9. Seasonal variation of speed and width from kinematic parameters of mode-1 nonlinear internal waves in the northeastern East China Sea

    NASA Astrophysics Data System (ADS)

    Cho, Chomgun; Nam, SungHyun; Song, Heechun

    2016-08-01

    To better understand the statistical and theoretical characteristics of nonlinear internal waves (NLIWs) in the broad continental shelf of the northeastern East China Sea (ECS), historical hydrographic data collected over 50 years between 1962 and 2011 are analyzed to calculate monthly climatology. Based on KdV and extended KdV models under the two-layer approximation (i.e., mode-1 NLIWs), the monthly climatology for propagating speed and characteristic width is constructed, ranging from 0.8 to 1.2 m s-1 and from O(102) to O(103) m, respectively. The result is consistent with a few previous in situ observations in the region. When NLIWs originating in the southeastern slope area approach the shallower regime (northwestward propagation), they propagate more slowly with neither break nor extinction, but with a shorter width, since both the Iribarren and Ostrovsky numbers are small (Ir ≪ 0.45 and Os ≪ 1, respectively). Limitations of the two-layered KdV-type models are discussed (e.g., an importance of mode-2 waves) in the context of occasional exte