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11.
两株琼胶酶高产细菌的筛选和鉴定 总被引:4,自引:1,他引:4
从海洋环境中筛选得到两株琼胶酶的高产菌株,通过形态观察和生理生化反应,确定它们属于弧菌属,通过BIOLOG细菌鉴定系统鉴定,并同弧菌属标准菌株分析比较,确定上方宝剑两株菌都是塔式弧菌(Vibrio tubiashii),这两株菌在碳源利用方面存在差别。 相似文献
12.
The size, mass, and composition of plastic debris in the western North Atlantic Ocean 总被引:1,自引:0,他引:1
Skye Morét-Ferguson Kara Lavender Law Ellen K. Murphy Christopher M. Reddy 《Marine pollution bulletin》2010,60(10):1873-1878
This study reports the first inventory of physical properties of individual plastic debris in the North Atlantic. We analyzed 748 samples for size, mass, and material composition collected from surface net tows on 11 expeditions from Cape Cod, Massachusetts to the Caribbean Sea between 1991 and 2007. Particles were mostly fragments less than 10 mm in size with nearly all lighter than 0.05 g. Material densities ranged from 0.808 to 1.24 g ml−1, with about half between 0.97 and 1.04 g ml−1, a range not typically found in virgin plastics. Elemental analysis suggests that samples in this density range are consistent with polypropylene and polyethylene whose densities have increased, likely due to biofouling. Pelagic densities varied considerably from that of beach plastic debris, suggesting that plastic particles are modified during their residence at sea. These analyses provide clues in understanding particle fate and potential debris sources, and address ecological implications of pelagic plastic debris. 相似文献
13.
Angelina Metaxatos 《Journal of Sea Research》2004,52(4):189
The venerid bivalve Callista chione is the most prominent suspension-feeding bivalve inhabiting the soft bottom of coastal areas in the northern Euboikos Gulf (Aegean Sea), where it is exploited by small-scale fishery. The parameters of the von Bertalanffy growth function were estimated and the somatic production-to-biomass ratio was found to be 0.45 y−1. The maximum age of adult individuals was 17 years. The species is gonochoristic, its oocyte diameter ranged from 54.5 to 120 μm with a conspicuous jelly-coat. Microscopical examination of the gonads showed that gonadal production did not start until the second year of life. The observations on the gonadal cycle indicate that this bivalve is capable of year-round reproduction. 相似文献
14.
Blair Thornton Seiki Ohnishi Tamaki Ura Naoteru Odano Shun Sasaki Tsuneo Fujita Tomowo Watanabe Kaoru Nakata Tsuneo Ono Daisuke Ambe 《Marine pollution bulletin》2013
An estimated 3.5 ± 0.7 × 1015 Bq of 137Cs is thought to have been discharged into the ocean following the melt down at Fukushima Dai-ichi Nuclear Power Plant (F1NPP). While efforts have been made to monitor seafloor radiation levels, the sampling techniques used cannot capture the continuous distribution of radionuclides. In this work, we apply in situ measurement techniques using a towed gamma ray spectrometer to map the continuous distribution of 137Cs on the seafloor within 20 km of the F1NPP. The results reveal the existence of local 137Cs anomalies, with levels of 137Cs an order of magnitude higher than the surrounding seafloors. The sizes of the anomalies mapped in this work range from a few meters to a few hundreds of meters in length, and it is demonstrated that the distribution of these anomalies is strongly influenced by meter scale features of the terrain. 相似文献
15.
郑文姣 《广东海洋大学学报》2009,29(2)
随着海上责任保险第三人权利保护的问题受到人们的日益重视,各国普遍赋予了海上责任保险第三人对保险人的直接请求权,但各国立法基本上未考虑到强制海上责任保险的特殊性,从而没有明确区分自愿海上责任保险中第三人直接请求权与强制海上责任保险中第三人直接请求权不同的权利属性,因而只笼统地对海上责任保险第三人行使直接请求权的条件做出概括性规定,这无法真正实现强制海上责任保险充分维护第三人利益与社会公共利益的立法价值。针对这一立法缺陷,提出应在明确自愿海上责任保险中的第三人直接请求权与强制海上责任保险中的第三人直接请求权具有不同权利属性的前提下,针对这两种不同的海上责任保险规定第三人不同的权利行使条件。 相似文献
16.
海洋生态产品价值实现作为一项系统性、复杂性战略工程,尚处于实践初期阶段,明确其关键影响因素,对于建立健全海洋生态产品价值实现机制具有重要意义。文章在厘清海洋生态产品价值实现机理与影响因素的基础上,构建海洋生态产品价值实现影响因素指标体系,运用DEMATEL-ISM方法建模分析各因素的相互影响程度、因果性质以及影响因素多层递阶结构,并采用MICMAC方法划分各影响因素属性,进而依据建模结果提出推进海洋生态产品价值实现的综合性建议。结果表明,海洋生态产品价值认知、资本投入、生态产业化、消费意愿、市场交易平台构建、激励机制与政策支持、利益相关者参与度与生态保护补偿机制是关键因素;海洋生态产品价值实现影响因素的多层递阶结构为4个层级,其中海洋生态产品价值认知与生态保护补偿机制作为独立因素位于最深层L4,市场交易平台构建作为依赖因素位于中心层L2。 相似文献
17.
南沙海区中生界岩相分布及构造特征 总被引:3,自引:0,他引:3
为了了解南中国海南部南沙群岛陆架-陆坡区中生代地层发育情况,作者通过综合分析该海区钻井、拖网及1987年以来采集的20000多公里的多道反射地震勘探等资料,得到了对该区中生界基本特征的如下新认识:空间分布上,南沙的中生界具有从北部的郑和-礼乐隆起南缘向南增厚的趋势;沉积岩相方面,东部三叠纪时为深海相,侏罗纪为浅海与三角洲相,白垩纪为浅海-内浅海相,而往西南部中生代的海水深度有变深的趋势;中-新生代变形上,在南沙西部的曾母盆地,中生界褶皱为复式的、非协调性的,南沙中部多为舒缓褶皱,东部仅在近巴拉望海槽地带出现小幅度的褶皱。结合围区中生界及特提斯构造域的发育特征,作者提出南沙地块上的海相中生界在大地构造上归属于残留在中特提斯洋北部减薄陆缘地壳上的中特提斯期海相沉积地层,是该海域油气资源勘探不可忽视的对象。 相似文献
18.
P. Cereceda P. Osses H. Larrain M. Farías M. Lagos R. Pinto R. S. Schemenauer 《Atmospheric Research》2002,64(1-4)
A project in northern Chile was undertaken to determine the origin and behaviour of fog in the coastal and inland locations of the Tarapacá Region. In the Pampa del Tamarugal, 50 km from the sea, conditions exist for the formation of radiation fog. Advective fog has been studied on the coast and orographic fog was observed at a few coastal sites near mountain ranges with elevations above 1000 m. Fog water collected by two standard fog collectors (SFC) for 3 1/2 years showed an average flux of 8.5 l m−2 day−1 on the coast and 1.1 l m−2 day−1 inland 12 km from the coastline. On only a few days in 10 months was water collected at the inland site of Pampa del Tamarugal. GOES satellite images are shown to illustrate the pattern of formation of the stratocumuli cloud over the sea, its approach to the coastline, the entrance of fog by corridors through the coastal range and the presence of radiation fog inland. The results are important for the understanding of fog formation and dissipation along the coastal mountain range and for the recognition of potential sites for the installation of fog water collectors, which can be used as a water source in the Atacama Desert. The results also provide vital information for use in the preservation of the unique ecosystems of the most arid desert of the world. 相似文献
19.
Bioremediation of petroleum hydrocarbons in anoxic marine sediments: Consequences on the speciation of heavy metals 总被引:3,自引:0,他引:3
Antonio Dell’Anno Francesca Beolchini Massimo Gabellini Laura Rocchetti Antonio Pusceddu Roberto Danovaro 《Marine pollution bulletin》2009,58(12):1808-1814
We investigated the effects of biostimulation and bioagumentation strategies applied to harbor sediments displaying reducing conditions and high concentrations of petroleum hydrocarbons and heavy metals. We compared the microbial efficiency of hydrocarbon removal from sediments maintained for 60 days in anoxic conditions and inoculated with acetate, sulfate-reducing bacterial strains and acetate and sulfate-reducing bacteria. All treatments determined a significant increase in the microbial growth and significant decreases of hydrocarbon contents and of redox potential values. The addition of sulfate-reducing bacterial strains to the sediment was the most efficient treatment for the hydrocarbon removal. In all experiments, significant changes of the heavy metals’ phase repartition were observed. The results reported here suggest that the biodegradation of petroleum hydrocarbons in anoxic marine sediments may be enhanced by stimulating microbial anaerobic metabolism, but care should be applied to monitor the potential changes in the mobility and bioavailability of heavy metals induced by bio-treatments. 相似文献
20.
文章基于我国沿海11个省(自治区、直辖市)海洋环境和海洋经济的面板数据,将海洋产业结构和海洋产业劳动力要素投入作为控制变量,构建双对数面板数据模型,就海洋环境污染对海洋经济发展的影响进行实证分析。结果表明:海洋环境污染与海洋经济发展存在负相关关系,海洋产业结构与海洋经济发展存在正相关关系,海洋产业劳动力要素投入与海洋经济发展存在负相关关系。基于此,为促进海洋经济的可持续发展,提出加强海洋环境保护和治理、优化升级海洋产业结构以及培养和引进海洋专业人才的建议。 相似文献