东海渔山列岛浅海岩礁区大型消费者食源及营养级分析     

刘好真  郑丹  焦海峰  王莉  徐鹏  史西志  王一农  尤仲杰 《海洋与湖沼》2017,48(5):1036-1043

采用碳氮稳定性同位素技术分析了东海渔山列岛浅海岩礁区生物的碳氮稳定性同位素比值,研究了浅海岩礁区14种初级生产者、61种消费者的营养级。结果表明,东海渔山列岛浅海岩礁区消费者的营养级(TL)变化范围为2.000—4.760,推断东海渔山列岛浅海岩礁区生物有4个营养级;初级生产者δ~(15)N值变化范围为2.75‰—6.85‰,消费者δ~(15)N值变化范围为4.57‰—13.39‰;通过对不同生物δ~(15)N值的比较发现,各类别生物间的δ~(15)N值差异高度显著(P0.01),短滨螺(Littorina brevicula)的δ~(15)N值最低(4.57‰),中国花鲈(Lateolabrax maculatum)和黑鲷(Acanthopagrus schlegelii)的δ~(15)N值最大,分别为11.87‰和13.39‰;单因素方差分析(One-Way ANOVA)表明4类食源间δ~(15)N和δ~(13)C值差异高度显著(P0.01);食源分析表明,鱼类的贡献范围(0.00%—7.09%)最小,初级生产者的贡献范围(27.05%—57.99%)最大;比较发现不同海域同一种生物体内富集的15N量也存在差异,这也从一个侧面反映出不同海域间生物的群落结构和稳定性存在差异。  相似文献   

Contrasting hydrography and phytoplankton distribution in the upper layers of cyclonic eddies in the Mozambique Basin and Mozambique Channel     

T Lamont  RG Barlow 《African Journal of Marine Science》2017,39(3):293-306

Hydrographic data collected in cyclonic eddies in the Mozambique Channel and Basin revealed notable differences in temperature and salinity at a depth of 100 m, the upper mixed layer, the nitracline depths, and vertical distribution of chlorophyll-a (Chl-a). Differences in temperature and salinity did not show any consistent patterns. In contrast, the differences in the upper mixed layer, nitracline depths and the vertical Chl-a profile appeared to be driven by combined effects of eddy dynamics (i.e. shoaling of isopleths) and the seasonal variation in light availability and mixing conditions in the upper layers. Cyclonic eddies studied during austral spring and summer in the Mozambique Channel exhibited shallower upper mixed layers and nitracline depths, and deeper euphotic zones. Distinct subsurface Chl-a maxima (SCM) were associated with the stratified conditions in the upper layers of these eddies. In contrast, a cyclonic eddy studied during mid-austral winter in the Mozambique Basin had a shallower euphotic zone, deeper upper mixed layer and uniform Chl-a profiles. Another eddy sampled in the Mozambique Basin toward the end of winter showed a less pronounced SCM and roughly equal euphotic zone and upper mixed layer depths, suggestive of a transition from a well-mixed upper layer during winter to stratified conditions in summer.  相似文献   

Polar organic micropollutants in the coastal environment of different marine systems     

Karsten Nödler  Dimitra Voutsa  Tobias Licha 《Marine pollution bulletin》2014

Polar anthropogenic organic micropollutants are frequently detected in freshwater and discharged on large scale into marine systems. In this work the results of 153 samples collected from the shorelines of the Baltic Sea (Germany), Northern Adriatic Sea (Italy), Aegean Sea and Dardanelles (Greece & Turkey), San Francisco Bay (USA), Pacific Ocean (USA), Mediterranean Sea (Israel), and Balearic Sea (Spain) are presented. The samples were analyzed for various classes of micropollutants such as pharmaceuticals, corrosion inhibitors, biocides, and stimulants. Caffeine, paraxanthine, theobromine, tolyltriazole, 1H-benzotriazole, and atrazine were detected in >50% of all samples. The detection frequencies of carbamazepine, iopamidol, diuron, sulfamethoxazole, paracetamol, theophylline, and atenolol were between 20% and 32%. As caffeine is linked to untreated wastewater, the widespread occurrence of raw sewage in marine environments and thus potentially elevated nutrient concentrations and risk for the presence of wastewater-related pathogens is remarkable.  相似文献   

Reproductive traits and conservation needs of the endemic gammarid Laurogammarus scutarensis () from the Skadar Lake system,Balkan Peninsula     

《Limnologica》2014

Europe is one of the global hotspots of freshwater amphipod diversity with a number of endemic species, yet many of European freshwater ecosystems are under extreme anthropogenic pressure. Studying the biology and ecology of endemic species may substantially help to assess risk of extinction and define proxies for their conservation. Laurogammarus scutarensis is a Balkan endemic and the only species within the genus Laurogammarus G. Karaman 1984. Its distribution is restricted to temperature-stable, cool waters of the springs, streams and lower sections of a few rivers emptying to the north-western part of the Skadar Lake in Montenegro – an area under heavy anthropogenic pressure in recent years. We examined life history of the species in a limnocrene spring with year-round stable temperature (10 °C ± 0.5) by estimating its population structure over a year, fecundity, reproductive period and relationship between photoperiod and reproduction. These parameters were compared to those of other gammarids, including invasive species, in order to estimate the role of photoperiod in shaping life history of L. scutarensis, and to give insight into the possible conservation needs for that species. Our results show that the species is univoltine and its reproduction continues round the year. However, its intensity is synchronised with seasonal day length changes with the highest share of females breeding in spring and early summer. The population sex structure is strongly female biased in most of the year. Number of eggs laid depends positively on the female body length; however the mean brood size (15.53 eggs) of L. scutarensis is rather low when compared to other species. Also partial fecundity and mean body length at which individuals start to reproduce indicate that its reproductive potential is much lower than that of many other gammarid species, including those colonising many European water bodies in recent years. Concluding, the studied life history traits of L. scutarensis combined with its very narrow distribution range and peculiar thermal requirements reported in the literature provide as with the hint to define the species as vulnerable to threats posed by the habitat degradation and competition with other species. Taking into account the risk of invasion by alien species and progressive habitat loss, we are of the opinion that L. scutarensis should be recognised as an endangered species and that a conservation plan should be implemented to prevent its possible extinction.  相似文献   

Phosphorus forms and distribution in Zhejiang coastal sediment in the East China Sea   总被引：1，自引：0，他引：1  

Min CONG  Tao JIANG  Yu-zao QI  Hong-po DONG  De-qiang TENG  Song-hui LU 《国际泥沙研究》2014,29(2):278-284

Surface and core sediment samples were collected from Zhejiang coastal waters of the East China Sea to study phosphorus（P） forms and understand the potential release of P as well as adsorption.The sediments were extracted sequentially to determine four phosphorus fractions,and non-sequentially for total phosphorus（TP）.The total concentration of phosphorus in the surface sediments ranged from 527.2 to 680.5 mg kg-1.Inorganic P was the major form and accounted for 84-94%of TP.Among the four forms,P-Detrital was dominant（58.6-73.2%）,followed by P-CDB（10.5-20.9%）,P-Organic（6.1-15.9%）,and P-CFA（5.9-16.3%）.The distribution pattern of TP in the surface sediments was similar to that of P-Detrital and P-Organic,but different from P-CDB and P-CFA.A relatively high level of phosphorus was observed in estuarine sediments,reflecting the influence from terrestrial input.Phosphorus in all forms in core sediments at each station decreased with depth.In addition,potentially bio-available phosphorus accounted for 20-34%of TP.  相似文献   

山东及附近海域构造环境剪应力场分析     

季爱东  穆娟  张芹  曲均浩  郑建常 《地震地磁观测与研究》2014,(1):10-14

利用山东数字地震台网的地震波形记录,选取2007年以来台网记录清晰的ML≥2．0数字地震波形资料,计算每次地震的环境剪应力值τ0和矩震级MW,并分析其相关关系;结合山东地区地质构造和地震活动性特点,对胶东半岛及北部海域、南黄海北部地区、沂沭带地区、冀鲁豫交界地区应力场分布和时空变化进行细致分析,并探讨其区域特征及与地震活动性的关系。  相似文献   

Limnology of Opal Lake     

D. J. Forsyth  A. L. MacKenzie 《新西兰海洋与淡水研究杂志》2013,47(3):279-283

Opal Lake, a cold, acid lake on the central volcanic plateau of the North Island, New Zealand, had an average pH of 4.3 and was highly eutrophic. The biota was less diverse than in neighbouring near‐neutral waters. Macrophytes were rare; phytoplankton were mainly represented by the Chlorophyceae, and there were only 4 zooplankton species. The mean standing crop of macroinvertebrates was 6240 per square metre; this was higher than in other eutrophic lakes in the region and comprised more than 98% chironomid larvae represented by 4 species. Molluscs were absent. The fauna was more diverse than in more acid lakes of the .central volcanic plateau.  相似文献   

Critical depths for passage in braided rivers,Canterbury, New Zealand     

M. Paul Mosley 《新西兰海洋与淡水研究杂志》2013,47(3-4):351-357

Riffles and points of divergence of branch channels in braided rivers are critical controls upon passage of fish and recreational boats because they are points at which depths are at a minimum. Depths on randomly selected riffles were measured in braided reaches of the Ashley, Hurunui, and Rakaia Rivers and related to discharge; minimum depths encountered in extended reaches of these rivers at a range of flows have also been measured. The data can be used to predict minimum available passage depths at a specified flow, or conversely, to predict the discharge required to maintain a specified minimum passage depth. However, presently available estimates of critical minimum depths required for various instream uses (migration of salmonids, jetboating) appear excessively conservative, and minimum depth requirements must be more accurately determined before instream flow needs can be properly assessed.  相似文献   

Northern Adriatic phytoplankton response to short Po River discharge pulses during summer stratified conditions     

Damir Vilicic  Milivoj Kuzmic  Igor Tomažić  Zrinka Ljubešić  Sunčica Bosak  Robert Precali  Tamara Djakovac  Danijela Marić  Jelena Godrijan 《Marine Ecology》2013,34(4):451-466

A 275‐km‐long transversel Northern Adriatic profile from the mouth of the Po River (Italian Adriatic coast) to the Kvarner region (Croatian coastal island area) was investigated in three successive case studies in August 2008, 2009 and 2010. The short Po River pulses in August result in the surface advection of riverine water, nutrients and phytoplankton from the western to the eastern side of the Adriatic. This surface spreading exhibits inter‐annual variability depending on the riverine discharge in the preceding period. The Po River discharge pulse in August 2010 in particular resulted in an extraordinary tongue‐like advection of riverine water, nutrients, and phytoplankton towards the Eastern Adriatic coast. The phenomenon was detected using both satellite imagery and classical oceanographic measurements. In the advective water, toxic dinoflagellates were most abundant in August 2010, when the influence of the Po was greatest.  相似文献   

春末海南万宁海域浮游动物群落结构研究   总被引：4，自引：1，他引：3  

罗鸣  苗素英  于红兵  陈清潮  严岩 《海洋科学》2013,37(11):79-84

根据 2012 年春末在海南万宁海域所采集的浮游动物样品, 对该海域浮游动物的种类组成、饵料生物量、丰度和生物多样性进行了探讨, 采用大型多元统计软件 PRIMER5.0 对浮游动物的群落结构进行了分析。结果表明调查海域共有浮游动物 70 种、浮游幼虫 10 个类群, 其中优势种共有 6 种: 双尾溞 纽鳃樽、多毛类幼虫、短角长腹剑水蚤、鸟喙尖头 、尖额真猛水蚤和小拟哲水蚤。浮游动物生物量和丰度的平面分布相似, 主要分布在调查海域的北部和中部近岸处。 浮游动物具有较高的均匀度(0.70), 生物多样性指数较高(3.10)。群落结构聚类分析显示浮游动物可以分为 5 个生态类群。  相似文献