The seasonal foot printing mechanism of spring Arctic sea ice in the Bergen climate models     

GUO Dong  GAO Yongqi  GONG Daoyi 《极地研究(英文版)》2014,(4)

The influence of spring Arctic sea ice variability on the Pacific Decadal Oscillation(PDO) like sea surface temperature(SST) variability is established and investigated using an Atmosphere Ocean General Circulation Model(AOGCM) of the Bergen Climate Model version 2(BCM2). The spring Arctic sea ice variability affects the mid-latitudes and tropics through the propagation of the anomalous Eliassen-Palm(E-P) flux from the polar region to mid- and low-latitudes during boreal spring. The pathway includes anomalous upward wave activity, which propagates to the high troposphere from near the surface of the polar region, turns southward between 500 h Pa and 200 h Pa and extends downward between 50°N and 70°N, influencing the near surface atmospheric circulation. The alteration of the near surface atmospheric circulation then causes anomalous surface ocean circulation. These circulation changes consequently leads to the SST anomalies in the North Pacific which may persist until the following summer, named seasonal "foot printing" mechanism(SFPM).  相似文献   

Seasonal changes in sea ice conditions along the Northeast Passage in 2007 and 2012     

Lei Ruibo  Li Na  Li Chunhua  Jónsdóttir Ingibj?rg 《极地研究(英文版)》2014,(4)

Remote sensing data from passive microwave and satellite-based altimeters, associated with the data measured underway, were used to characterize seasonal and spatial changes in sea ice conditions along...  相似文献   

Thickness distribution and extent of sea ice and snow in Prydz Bay and surrounding waters observed in 2012/2013 austral summer     

CHENG Peng  HAN Hongwei  LEI Ruibo  LI Zhijun  LU Peng 《极地研究(英文版)》2014,(1):1-9

Three ship-based observational campaigns were conducted to survey sea ice and snow in Prydz Bay and the surrounding waters(64.40°S–69.40°S, 76.11°E–81.29°E) from 28 November 2012 to 3 February 2013. In this paper, we present the sea ice extent and its variation, and the ice and snow thickness distributions and their variations with time in the observed zone. In the pack ice zone, the southern edge of the pack ice changed little, whereas the northern edge retreated significantly during the two earlier observation periods. Compared with the pack ice, the fast ice exhibited a significantly slower variation in extent with its northernmost edge retreating southwards by 6.7 km at a rate of 0.37 km?d-1. Generally, ice showed an increment in thickness with increasing latitude from the end of November to the middle of December. Ice and snow thickness followed an approximate normal distribution during the two earlier observations(79.7±28.9 cm, 79.1±19.1 cm for ice thickness, and 11.6±6.1 cm, 9.6±3.4 cm for snow thickness, respectively), and the distribution tended to be more concentrated in mid-December than in late November. The expected value of ice thickness decreased by 0.6 cm, whereas that of snow thickness decreased by 2 cm from 28 November to 18 December 2012. Ice thickness distribution showed no obvious regularity between 31 January and 3 February, 2013.  相似文献   

Links between Arctic sea ice and extreme summer precipi- tation in China：an alternative view     

Petteri Uotila  Alexey Karpechko  Timo Vihma 《极地研究(英文版)》2014,(4)

Potential links between the Arctic sea-ice concentration anomalies and extreme precipitation in China are explored. Associations behind these links can be explained by physical interpretations aided by...  相似文献   

Identification of Fucans from Four Species of Sea Cucumber by High Temperature ~1H NMR     

WU Nian  ;CHEN Shiguo  ;YE Xingqian  ;LI Guoyun  ;YIN Li' ang  ;XUE Changhu 《青岛海洋大学学报(英文版)》2014,(5):871-876

Acidic polysaccharide, which has various biological activities, is one of the most important components of sea cucumber. In the present study, crude polysaccharide was extracted from four species of sea cucumber from three different geographical zones, Pearsonothuria graeffei（Pg） from Indo-Pacific, Holothuria vagabunda（Hv） from Norwegian Coast, Stichopus tremulu（St） from Western Indian Ocean, and Isostichopus badionotu（Ib） from Western Atlantic. The polysaccharide extract was separated and purified with a cellulose DEAE anion-exchange column to obtain corresponding sea cucumber fucans（SC-Fucs）. The chemical property of these SC-Fucs, including molecular weight, monosaccharide composition and sulfate content, was determined. Their structure was compared simply with fourier infrared spectrum analyzer and identified with high temperature 1H nuclear magnetic resonance spectrum analyzer（NMR） and room temperature 13 C NMR. The results indicated that Fuc-Pg obtained from the torrid zone mainly contained 2,4-O-disulfated and non-sulfated fucose residue, whereas Fuc-Ib from the temperate zone contained non-, 2-O- and 2,4-O-disulfated fucose residue; Fuc-St from the frigid zone and Fuc-Hv from the torrid zone contained mainly non-sulfated fucose residue. The proton of SC-Fucs was better resolved via high temperature 1H NMR than via room temperature 1H NMR. The fingerprint of sea cucumber in different sea regions was established based on the index of anomer hydrogen signal in SC-Fucs. Further work will help to understand whether there exists a close relationship between the geographical area of sea cucumber and the sulfation pattern of SC-Fucs.  相似文献   

Effect of Bacillus baekryungensis YD13 Supplemented in Diets on Growth Performance and Immune Response of Sea Cucumber（Apostichopus japonicus）     

YAN Fajun TIAN Xiangli DONG Shuanglin 《青岛海洋大学学报(英文版)》2014,(5):805-810

The effect of a potential probiotic on the growth performance and immune response of sea cucumber（Apostichopus japonicus） was investigated. Bacillus baekryungensis YD13 isolated from sea cucumber culturing ponds was added to sea cucumber basal feed as a probiotic in different doses（0, the control; 1×10^4（YD134）, 1×10^6（YD136） and 1×10^8（YD138） CFU g-1 of diet）, and administered orally to A. japonicus（initial mean wet weight 5.44 g ± 0.17 g）. The sea cucumbers were fed in 20 aquaria, 5 each treatment, for 60 d. At the end of growth trial, 20 sea cucumbers from each treatment were challenged with Vibrio splendidus. A. japonicus in YD134 and YD136 exhibited significantly better growth performance than control（P 〈0.05）. Five non-specific immune parameters including lysozyme, acid phosphatase, alkaline phosphatase, superoxide dismutase and catalase in coelomic fluid were measured to evaluate the immune response of A. japonicus to the probiotics. Results showed that all parameters were significantly improved when YD11 was supplemented in the dose of 1×10^6 CFU g^-1（P 〈0.05）. The cumulative incidence and mortality after the Vibrio splendidus challenge decreased significantly in sea cucumbers of YD136. Accordingly, 1×10^6 CFU g^-1 of YD13 in diet was recommended for the growth promotion and immune enhancement of A. japonicus.  相似文献   

Identification of five sea cucumber species through PCR-RFLP analysis     

Yingchun Lv  Rong Zheng  Tao Zuo  Yuming Wang  Zhaojie Li  Yong Xue  Changhu Xue  Qingjuan Tang 《中国海洋大学学报(英文版)》2014,13(5):825-829

Sea cucumbers are traditional marine food and Chinese medicine in Asia. The rapid expansion of sea cucumber market has resulted in various problems, such as commercial fraud and mislabeling. Conventionally, sea cucumber species could be distinguished by their morphological and anatomical characteristics; however, their identification becomes difficult when they are processed. The aim of this study was to develop a new convenient method of identifying and distinguishing sea cucumber species. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of mitochondrial cytochrome oxidase I gene (COI) was used to identifing five sea cucumber species (Apostichopus japonicus, Cucumaria frondosa, Thelenota ananas, Parastichopus californicus and Actinopyga lecanora). A 692 bp fragment of COI was searched for BamHI, KpnI, PstI, XbaI and Eco31I restriction sites with DNAMAN 6.0, which were then used to PCR-RFLP analysis. These five sea cucumber species can be discriminated from mixed sea cucumbers. The developed PCR-RFLP assay will facilitate the identification of sea cucumbers, making their source tracing and quality controlling feasible.  相似文献   

Field experiments of multi-channel oceanographic fluorescence lidar for oil spill and chlorophyll-a detection     

Xiaolong Li  Chaofang Zhao  Youjun Ma  Zhishen Liu 《中国海洋大学学报(英文版)》2014,13(4):597-603

A Multi-channel Oceanographic Fluorescence Lidar (MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a (Chl-a), has been developed using the Laser-induced Fluorescence (LIF) technique. The sketch of the MOFL system equipped with a compact multi-channel photomultiplier tube (MPMT) is introduced in the paper. The methods of differentiating the oil fluorescence from the background water fluorescence and evaluating the Chl-a concentration are described. Two field experiments were carried out to investigate the field performance of the system, i.e., an experiment in coastal areas for oil pollution detection and an experiment over the Yellow Sea for Chl-a monitoring. In the coastal experiment, several oil samples and other fluorescence substances were used to analyze the fluorescence spectral characteristics for oil identification, and to estimate the thickness of oil films at the water surface. The experiment shows that both the spectral shape of fluorescence induced from surface water and the intensity ratio of two channels (I ₄₉₅/I ₄₀₅) are essential to determine oil-spill occurrence. In the airborne experiment, MOFL was applied to measure relative Chl-a concentrations in the upper layer of the ocean. A comparison of relative Chl-a concentration measurements by MOFL and the Moderate Resolution Imaging Spectroradiometer (MODIS) indicates that the two datasets are in good agreement. The results show that the MOFL system is capable of monitoring oil spills and Chl-a in the upper layer of ocean water.  相似文献   

湛江地区一次冷锋型海雾微物理特征   总被引：1，自引：1，他引：0       下载免费PDF全文

吕晶晶  牛生杰  赵丽娟  张羽  徐峰 《大气科学学报》2014,37(2):208-215

利用2010年3月31日—4月2日冷锋天气系统影响下湛江海雾综合观测资料,分析了海雾的微物理特征及海雾过程中气溶胶粒子谱的演变特征。结果表明,海雾的生消与风场密切相关,海雾生成和发展与较强的ESE气流相联系,而弱的NE气流则会促使海雾减弱或消散。湛江海雾的雾滴数浓度为100~102cm-3,液态含水量为0.001~0.232 g·m-3,雾滴平均半径小于10μm,雾滴峰值半径多位于1.4μm。海雾雾滴谱分布以单调递减谱为主,谱宽超过20μm,且雾发展过程中雾滴谱谱宽存在突然增宽和迅速减小的现象。海雾过程中雾滴数浓度的变化主要是由半径小于5μm的雾滴数密度变化引起的。海雾过程对气溶胶粒子的湿清除效果并不显著,雾过程中粒径小于0.1μm和大于4μm的气溶胶粒子数密度显著减少,但在雾消散后又迅速恢复到雾发生前的水平。  相似文献   

Effects of the oophagous bivalve Acesta oophaga on the morphology and fecundity of its deep‐sea tubeworm host,Lamellibrachia luymesi     

Zair P. Burris  Joshua P. Lord  Craig M. Young 《Marine Ecology》2014,35(1):106-111

The deep‐sea bivalve Acesta oophaga lives attached to the anterior end of the vestimentiferan tubeworm, Lamellibrachia luymesi, at cold methane seeps. The bivalve is found almost exclusively on female tubeworms, where it consumes the lipid‐rich eggs of L. luymesi that are spawned year round (Biological Bulletin, 209, 2005, 87). It is apparent that A. oophaga benefits directly from this close association, but the consequences for the tubeworm host may be more complicated than just a simple predator–prey interaction. Since A. oophaga completely surrounds the tube opening and plume of the worm, it is likely that its presence would limit oxygen uptake by L. luymesi, thereby inhibiting worm growth and reproduction. We hypothesized that occupied tubeworms would compensate for this by growing larger plumes for oxygen uptake. To explore the effects of bivalve presence/absence on female tubeworms, several morphological features, including body size, plume length, tube diameter, and tube segment length, as well as instantaneous fecundity, were compared. Results suggest that the mere presence of A. oophaga has a significant impact on the morphology of its host worm, as all measures of worm size, except for tube segment length, were significantly greater with clams present. Additionally, instantaneous fecundity was 3.5 times higher in occupied worms, implying that tubeworms are not oxygen‐deprived or energy limited as a result of bivalve presence. Our findings suggest that the association between these two deep‐sea organisms may be a more complex form of symbiosis than the simple predator–prey relationship, as previously thought.  相似文献