渤海湾4.2ka事件初步研究     

商志文  田立柱  范昌福  李建芬  王福  姜兴钰  王宏 《地质通报》2016,35(10):1614-1621

相距3~20km的岭头、罾口河、俵口和空港物流中心4处埋藏牡蛎礁体的年代学研究证实,开始发育的时间不同,但同时在4.2~4.0ka cal BP时结束建礁,即其灭亡与"4.2ka事件"在时间上重合。岭头、罾口河剖面O稳定同位素和罾口河剖面孢粉数据进一步表明,4.5~4.3ka cal BP时研究区气候出现变冷变干的趋势,4.3~4.2ka cal BP逐渐好转,推测这一气候波动变化过程可能是对"4.2ka事件"的响应。  相似文献   

Managing marine invasive species through public participation: Lionfish derbies as a case study     

《Marine Policy》2016

The management of invasive species can be facilitated by public participation. The drivers of public involvement and success at invasive removal in tournaments (derbies) to catch Indo-Pacific lionfish (Pterois volitans/miles) in the Western Atlantic were examined. Information on 69 lionfish derbies held in the wider Caribbean region from 2010 to 2015 was compiled. Derbies attended mainly by artisanal fishers reported lower catches but higher participation than derbies dominated by recreational divers or attended by a mixed public. As predicted, the number of lionfish caught increased with effort and with time since lionfish were established in an area. In contrast, participation was best predicted by national wealth (GDP per capita) and number of local dive shops. From the point of view of public engagement, derbies should therefore be held in areas where lionfish are well established, and where the pool of potential participants is large. However, if the management goal is instead to slow the invasion, early detection is critical. The focus should then shift to areas where no or very few lionfish have been detected, and the derby approach modified to a more frequent or continuous, monitoring-like incentive scheme.  相似文献   

牡蛎中氨基酸的傅里叶变换近红外光谱法快速定量测定     

于颖  宋金明  俞立东  孙萱 《海洋科学》2016,40(12):1-7

本文通过乘法散射校正(multiplicative scattering correction MSC)、一阶求导(1st Derivative,Db1)和Norris平滑等傅里叶变换近红外光谱定量分析数学模型,用交叉验证法确定了最优化建模参数,构建了牡蛎中氨基酸的快速定量测定方法。结果表明,牡蛎近红外光谱与氨基酸含量化学计量学拟合,线性相关系数为0.9860,交叉验证后线性相关系数为0.9794,对牡蛎样品进行检测,结果与传统的氨基酸分析仪的测试结果相比,相对误差小于2.5%,方法的精密度(RSD)小于1.0%,本文建立的傅里叶变换近红外光谱法定量分析牡蛎中氨基酸具有快速、准确、操作简便等特点,测定重复性优于氨基酸分析仪法。  相似文献   

Conceptual hydrodynamic-thermal mapping modelling for coral reefs at south Singapore sea     

《Applied Ocean Research》2016

Coral reefs are important ecosystems that not only provide shelter and breeding ground for many marine species, but can also control of carbon dioxide level in ocean and act as coastal protection mechanism. Reduction of coral reefs at Singapore coastal waters (SCW) region remains as an important study to identify the environmental impact from its busy industrial activities especially at the surrounding of Jurong Island in the south. This kind of study at SCW was often being related to issues such as turbidity, sedimentation, pollutant transport (from industry activities) effects in literatures, but seldom investigated from the thermal change aspect. In this paper, a computational model was constructed using the Delft3D hydrodynamic module to produce wave simulations on sea regions surrounding Singapore Island. The complicated semi-diurnal and diurnal tidal wave events experienced by SCW were simulated for 2 weeks duration and compared to the Admiralty measured data. To simulate the thermal mapping at the south Singapore coastal waters (SSCW) region, we first adapted a conversion of industrial to thermal discharge; then from the discharge affected area a thermal map was further computed to compare with the measured coral map. The outcomes show that the proposed novel thermal modelling approach has quite precisely simulated the coral map at SSCW, with the condition that the near-field thermal sources are considered (with the coverage area in the limit of 20 km × 20 km).  相似文献   

Redundancy and diversity of functional reef fish groups of the Mexican Eastern Pacific          下载免费PDF全文

Rosalia Aguilar‐Medrano  Luis Eduardo Calderon‐Aguilera 《Marine Ecology》2016,37(1):119-133

Coral reefs are in crisis worldwide. Fish play a key role in the resilience of reefs because most of the biomass of the ecosystem flows through them. Evidence indicates that the response to stressors will vary markedly depending on the resilience of the ecosystem. In order to assess the functional groups of reef fishes, morphometric and ecomorphological analyses were carried out on the shape and diet of 117 reef fish species from the Mexican Eastern Pacific (MEP) from 23°N to 15°N, spanning the years 2009–2012. Six trophic groups were identified and subdivided into 19 functional groups: (A) detritus and plants consumers, three morphologies; (B) plants and zoobenthos consumers, four morphologies; (C) zoobenthos consumers, two morphologies; (D) zoobenthos and zooplankton consumers, three morphologies; (E) zooplankton and nekton consumers, three morphologies; and (F) nekton consumers, four morphologies. Our main conclusions are: (i) fish communities of the MEP have a high degree of ecological redundancy; (ii) fish diversity is not related to the coral cover; and (iii) the combination of using both morphology and diet produce a more effective classification of functional groups. Future studies such as these will allow a deeper understanding of environment and it will help illuminate the effects of fish morphology and diet on population structure.  相似文献   

Symbiodinium (internal transcribed spacer 2) diversity in the coral host Agaricia lamarcki (Cnidaria: Scleractinia) between shallow and mesophotic reefs in the Northern Caribbean (20–70 m)          下载免费PDF全文

Matthew Q. Lucas  Michael Stat  Matthew C. Smith  Ernesto Weil  Nikolaos V. Schizas 《Marine Ecology》2016,37(5):1079-1087

This study investigated differences in Symbiodinium diversity in the scleractinian coral species Agaricia lamarcki between shallow (20–25 m) and mesophotic (50–70 m) depths in the Northern Caribbean. Corals were sampled in each of four shallow sites (20–25 m; n = 18) and three mesophotic sites (50–70 m; n = 18) from Mona Island (Puerto Rico) and the US Virgin Islands during a mesophotic exploratory cruise and from the La Parguera shelf edge, off Southwestern Puerto Rico. Symbiodinium diversity was assessed using internal transcribed spacer 2 sequences clustered into operational taxonomic units (OTUs). Clustering resulted in eight clade C OTUs and one clade D OTU. Of these, there were three common Symbiodinium OTUs consisting of C3 and D1a.N14 in shallow reefs and C11.N4 in mesophotic reefs. Statistical tests (permutational multivariate analysis of variance and analysis of similarity) showed significant differences between clade C Symbiodinium OTUs in A. lamarcki colonies located at shallow and mesophotic depths, indicating symbiont zonation. Symbiodinium diversity in A. lamarcki from the Northern Caribbean is comparable to previous reports in the Southern Caribbean for this species. This is the first report of the thermal tolerant species Symbiodinium trenchii (D1a) in A. lamarcki.  相似文献   

How long does oyster shell last on an oyster reef?     

Eric N. Powell  John N. Kraeuter  Kathryn A. Ashton-Alcox 《Estuarine, Coastal and Shelf Science》2006,69(3-4):531

A reduction in population abundance, brought on by an unprecedented 6 years of low recruitment, has reduced shell input through natural mortality on Delaware Bay oyster beds. Quantitative stock surveys provide an estimate of surficial shell over the same time period, permitting the reconstruction of the time history of shell since 1998 and estimation of the rates of shell addition and loss. Shell loss rates were unexpectedly high. In most cases, half of the shell added to an oyster bed in Delaware Bay in a given year is lost over a subsequent period of 2–10 years. Unexpectedly, the shortest half-lives, typically two to three years, are at intermediate salinities. Half-lives increase upbay into lower salinity and downbay into higher salinity to about 10 years. Minimal shell doubling times were calculated under the assumption of no shell loss, a maximum accretion rate. Minimal doubling times vary from somewhat less than a decade to more than a score of years. Doubling times of decadal scale emphasize that shell has the potential to accumulate rapidly on human time scales. The rarity of definitive documentation of shell accumulation, in terms of reef vertical accretion or lateral expansion, can only be explained if most shell produced yearly does not long remain recognizably intact. Doubling times are not rapid on the scale of oyster generation time, however. Management of essential fish habitat in the estuarine realm must include management of the shell budget and management of commercial shell-producing species must include the provision of animals as carbonate producers for habitat maintenance. Shell, at least in estuarine habitats, may have low preservational potential, even in areas that, when preserved, will appear to be shellbeds. The biases in the fossil record may not be minimized in shell-rich environments of preservation because shelliness does not imply good preservability.  相似文献   

Distribution of Living Larger Foraminifera NW of Sesoko-Jima, Okinawa, Japan   总被引：3，自引：0，他引：3  

Johann  Hohenegger 《Marine Ecology》1994,15(3-4):291-334

Abstract. Living, symbiont-bearing, larger foraminiferids restricted to the photic zone incorporate mechanisms blocking solar radiation and water current transportation. They can be divided in two groups according to their wall structure: 1, Families with opaque test walls, reducing light penetration: Peneroplids inhabit shallow-water environments from the intertidal ( Peneroplis in large numbers) down to 40 m ( Dendritina , preferring sandy substrates). Soritids are restricted to subtidal environments with less water turbulence and range from the reef moat down to 60 m. Amphisorus and Marginopora are common down to 30 m, whereas Parasorites is restricted to deeper parts of the reef slope. Alveolinella can be found in the upper 40 m of the reef slope. 2. Families with hyaline test walls, adjusted for light penetration: amphisteginids inhabit the whole photic zone, demonstrating a correlation of test flattening with increasing depth. Calcarinids cling with their spines to firm substrates such as algal thalli or macroids. Baculogypsina is restricted to high energetic regions on the reef flat. Calcarina inhabits similar environments, extending its distribution range within fore reefs down to 80 m. Baculogypsinoides is a dominant calcarinid genus from 30 to 70 m depth. Within nummulitids, Heterostegina prefers hard substrates on the reef slope, while Assilina (= Operculina ) is frequent in deeper parts and is independent of substrates. Sandy bottoms from 30 to 60 m are inhabited by the last living representative of the genus Nummulites, N. venosus . The giant foraminifer Cycloclypeus , with test sizes up to 7 cm, is restricted to fore reef areas below 50 m down to the base of the photic zone.  相似文献   

Trophic Structure and Community Composition of Polychaetes Inhabiting Some Sabellaria alveolata (L.) Reefs Along the Valencia Gulf Coast, Western Mediterranean     

R. Porras    J. V. Bataller    E. Murgui  M. T. Torregrosa 《Marine Ecology》1996,17(4):583-602

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太平洋牡蛎精液的超低温保存     

李贇  王品虹  贺桂珍  赵强 《中国海洋大学学报(自然科学版)》2002,32(2):207-211

利用解剖法采集太平洋牡蛎精液 ,用自然海水做基础溶液 ,配制不同浓度的 DMSO(二甲亚砜 )作为超低温保护剂 ,在液氮 (L N2 )面上不同高度进行预处理 ,投入 LN2 内保存 ,升温解冻后 ,检测精子成活率。结果表明 ,DMSO处理浓度、预处理温度及时间和升温方式对超低温保存成活率均具有显著影响。其中 ,用 10 % DMSO在 LN2 面上 17cm预处理 6 min,采用 16～ 17℃流水不完全解冻 ,效果最好 ,超低温保存精子成活率可达 70 %。与新鲜精子相比 ,在 L N2 内保存一天的精子 ,授精能力没有明显变化。  相似文献