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991.
《Marine pollution bulletin》2014,83(1-2):66-75
Composition and abundance of persistent buoyant litter (plastics, polystyrene and manufactured wood) were investigated at riversides and on adjacent coastal beaches of four rivers flowing into the SE Pacific Ocean. Persistent buoyant litter made up the main share of litter at riversides (36–82%) and on coastal beaches near the river mouths (67–86%). The characteristic litter composition of each river is attributable to human influences along its course. Riverine litter items were deposited to both sides of the river mouths on coastal beaches, and their abundance generally declined with distance from the river mouth. However, maximum litter accumulations were often found on beaches north of the river mouth, suggesting a long-term influence of the prevailing equatorward low-level jet along the Chilean coast. The results confirm that riverine transport has an important impact on litter abundances on coastal beaches. 相似文献
992.
内蒙古东部林西地区是二连盆地外围石炭-二叠系油气勘探的重要潜力区之一.为了研究上二叠统林西组烃源岩有机岩石学特征,对野外露头剖面的林西组烃源岩开展了总有机碳、有机显微组分、镜质体反射率及岩石热解等测试分析.结果表明:林西组烃源岩总有机碳分布在0.63%~1.30%,平均为0.87%,所有样品含量均大于0.6%;有机显微组分分布在0.27%~3.66%,平均值为2.08%,其中95.24%的样品达到1.0%以上,表明有机质丰度达到了“较好”至“好”级别;镜质体反射率分布在1.26%~2.58%,平均值为1.88%,其中90.47%的样品含量大于1.3%,镜质体反射率较高,表明有机质成熟度达到“高成熟”至“过成熟”阶段;岩石热解氢指数分布在8×10-3~89×10-3,平均为27.52×10-3,表明有机质类型归属于Ⅲ型.综合评价表明林西地区上二叠统林西组烃源岩属于“较好—好”烃源岩,生烃潜力较大,具有较好的油气资源前景. 相似文献
993.
我国是海洋渔业大国,为了有效保护渔业资源和渔民生命财产安全,需建立渔船动态监管信息系统。我国自主研发的北斗卫星导航系统集定位、导航和双向短报文通信为一体,特别适用于我国海洋渔业安全监管领域。本文描述了基于北斗卫星的船舶动态监控系统的设计,并详细介绍了该系统的主要功能。目前,该系统已在全国各地投入使用,大大提高了渔业生产和渔船安全救助能力。 相似文献
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996.
Suzuki G Kai S Yamashita H Suzuki K Iehisa Y Hayashibara T 《Marine pollution bulletin》2011,62(12):2803-2812
The initial factors that cause a decline in the survival of in situ settled corals remain poorly understood. In this study, we demonstrated through field experiments that the design of artificial grid plates may influence the initial survival of Acropora corals, with narrower grids being the most effective. In fact, grid plates with a 2.5-cm mesh presented the highest recorded survival rate (14%) at 6 months after settlement (representing approximately 50 corals per 0.25 m2 of plate). This is the first study where such high survival rates, matching those of cultures under aquarium conditions, were obtained in the field without using additional protective measures, such as guard nets against fish grazing after seeding. Therefore, our results provide a foundation for establishing new and effective coral restoration techniques for larval seeding, in parallel to clarifying the details of the early life stages of reef-building corals. 相似文献
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998.
南海北部陆架区底层渔业资源的空间分布特征 总被引:5,自引:0,他引:5
根据2006年10月至2007年9月南海北部大陆架海域4个航次底拖网调查资料,分析了该海域渔业资源的种类组成、种类丰富度和渔获率的空间分布。结果表明,渔获种类数以湛江断面最多(405种),汕头断面最少(337种)。种类数随水深变化呈非对称正态分布,以40—80m水深组种类数最多。物种丰富度指数D的空间分布与种类数基本一致。在总渔获物中,鱼类、头足类和甲壳类3大类群重量组成比例为80:12:8,在断面分布上,组成比例鱼类以珠江口断面最高,头足类以湛江断面最高,甲壳类以阳江断面最高。在水深分布上,鱼类占比随水深的增加而增加,头足类占比在40—100m水深较高,甲壳类在10—20m浅水区最高。鱼类最主要的优势种有6种,其中,深水金线鱼主要在90—120m水深占优势,黄鳍马面鲀在60—90m水深占优势,条尾绯鲤在60—120m水深占优势,单棘豹鲂鮄在120—200m水深占优势,六指马鲅在30—60m水深占优势,龙头鱼在10—30m水深占优势。鱼类渔获率断面分布以珠江口和粤西海域较高,汕头海域最低;水深分布渔获率随水深的增加而增加。头足类渔获率以粤西和珠江口海域较高,粤东海域较低;在100m水深范围内,渔获率随水深的增... 相似文献
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1000.
The study was conducted during two cruises of June–August 2006 (summer),and January–February 2007 (winter) in the Huanghai (Yellow) Sea and East China Sea.Spatial and temporal variations of zooplankton abundance,biomass and community structure and its relation to currents and water masses over the continental shelf were examined.A total of 584 zooplankton species/taxa and 28 planktonic larvae were identified during the two surveys.Copepods were the most abundant component among these identified groups.Zooplankton abundance and biomass fluctuated widely and showed distinct heterogeneity in the shelf waters.Five zooplankton assemblages were identified with hierarchical cluster analysis during this study,and they were Huanghai Sea Assemblage,Changjiang Estuary Assemblage,Coastal Assemblage,East China Sea Mixed-water Assemblage and East China Sea Offshore Assemblage.Seasonal changes of zooplankton community composition and its geographical distribution were detected,and the locations of the faunistic areas overlap quite well with water masses and current systems.So we suggest that the zooplankton community structure and its changes were determined by the water masses in the Huanghai Sea and East China Sea.The results of this research can provide fundamental information for the long-term monitoring of zooplankton ecology in the shelf of Huanghai Sea and East China Sea. 相似文献