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1.
塑料垃圾通过各种途径进入海洋,海洋塑料污染已成为全球性环境问题。本文系统总结了国内外塑料污染的研究历程与现状,发现直接或者间接来源的微塑料在环境中广泛积累,呈全球化分布趋势;重点探讨了我国微塑料的来源、分布以及污染形势和生态影响,发现我国微塑料污染形势严峻,覆盖范围广泛,甚至涉及食品安全领域。塑料的生物降解是受到高度关注的研究领域,本文通过对微塑料的生物降解途径的归纳,总结了塑料降解的过程、生物种类以及相关的降解酶等,以期为海洋微塑料污染的治理提供启示。目前微塑料污染已经引起世界各国的广泛关注,但对海洋环境中微塑料的鉴定以及污染物消除技术等研究极少,迫切需要开展相关研究工作。 相似文献
2.
微塑料(粒径5mm的塑料)作为海洋环境中一类新型污染物正受到越来越多的关注。我们从微塑料来源、分布和生态影响等方面总结分析了近年来海洋微塑料研究的进展。结果表明,海洋中的微塑料主要来源于在阳光、风浪和海流等作用下的海上塑料垃圾的分解,陆源塑料垃圾输入、海上船只塑料垃圾的丢弃、水产养殖业漂浮装置的废弃等是海洋中塑料垃圾的主要来源。海洋微塑料分布呈全球化趋势,近岸、大洋、深海和极地都有微塑料的存在,已有研究表明深海是微塑料的主要汇集区。微塑料不但会影响藻类的光合作用,还会影响一些海洋生物的产卵量和繁殖能力,甚至会引起某些海洋生物的营养不良甚至死亡;微塑料自身含有和表面富集的污染物会在水动力作用下影响污染物的全球分布并对海洋生物产生复合毒性影响。为减少海洋塑料垃圾,控制海洋微塑料污染并为污染防治提供支撑,保护海洋环境安全和人类健康,今后的研究方向将主要包括:不同粒径微塑料的快速分离和在线鉴别方法的建立;水动力对微塑料全球迁移变化的影响;微塑料复合毒性对海洋生态环境的污染效应及机制;管理和技术体系以及相关政策法规的制定等。 相似文献
3.
海洋微塑料污染是全球共同面对的重要环境问题之一。过去10 a,海洋微塑料研究发展迅速,但也暴露出一些亟待解决的关键科学问题,包括突破小粒径微塑料和纳米塑料的检测技术瓶颈、建立标准化的微纳塑料分析检测方法、优化海洋微塑料输运模型以及完善生态风险评估方案等。本文简要概述了近海、大洋和极地微塑料污染的现状,总结了海洋微塑料研究在样品采集和检测分析方面存在的挑战、在海洋微塑料存量估算和海洋微塑料输运模拟及生态风险评估方面存在的不足等,并展望了海洋微塑料未来研究方向,旨在为海洋微塑料常规监测、科学研究、风险评估和治理管控等方面提供借鉴和参考。 相似文献
4.
微塑料在海洋环境中广泛分布并不断累积,对海洋生态产生严重影响,已引起世界各国学者、管理者、非政府组织等社会各界的高度关注.海洋微塑料污染研究是近10 a来才发展起来的新兴研究领域,但却发展迅猛,已成为国际研究的热点和前沿.我国海洋微塑料污染研究发展较晚,与国际同行相比还有较大差距,系统性的中文文献也相对较少.本研究在对海洋微塑料污染研究国内外进展进行总结和回顾的基础上,比较分析了我国海洋微塑料污染研究与世界同领域之间的差距,归纳提出海洋微塑料污染研究应从微塑料在海洋中的时空分布、微塑料理化特性以及微塑料的海洋生态效应等三大关键问题加强研究,并围绕这些关键问题在研究方法、技术手段、危害评估标准体系等方面不断规范和创新,以促进我国海洋微塑料污染研究的快速发展. 相似文献
5.
海洋塑料作为一类具有潜在生态风险的污染物，已经引起了研究人员的重点关注。大到数米的塑料垃圾，小到微米级的微塑料，塑料污染物以各种形式在海洋环境中广泛存在。因能长期以固体形式赋存于海水和沉积物中，塑料污染物比溶解性污染物更难在海洋介质中均匀分散；但近年来，各项调查活动却在远离塑料来源的大洋、极地和深海中均发现了塑料污染物，这显然与塑料在海洋环境中的迁移息息相关。一方面，海洋中塑料污染物的分布和迁移受到塑料自身性质以及多种环境因素的影响。因此，针对海洋塑料污染物设计监测方案时，有必要通过对这些因素的研判，规范和优化采样方案，有效提高采样代表性。另一方面，了解海洋塑料污染物迁移和归趋的影响因素，也是预测塑料污染物蓄积和富集的海域或层次，推断其在海洋生境中的暴露情况，进而预测其潜在风险的必要前提。本文归纳了海洋塑料污染物迁移规律的相关研究，分析了影响海洋中塑料污染物水平和垂直分布的因素，总结并列举了在海洋水体和沉积物介质中塑料污染物监测活动的常用采样方法，分析了塑料污染物监测活动方案的制订依据和注意事项。 相似文献
6.
微塑料是海洋中一类重要的污染物,海洋微塑料污染已引起全球关注。根据目前的研究成果和研究热点,本文探索了将海洋微塑料从来源、材料、形状、颜色、大小、密度和状态7个方面进行了分类,综述了海洋微塑料在海水、沉积物和生物中的分布特征、相互迁移及影响因素,污染源、环境条件和微塑料本身的特征对其分布的影响最大,迁移使得微塑料在海洋环境中普遍存在,并且已经对海洋生物的代谢、生存和繁殖都构成了威胁。未来应对微塑料的分类、采样和测定进行统一规范;重点关注100μm以下的微塑料,发展微塑料定量和鉴别的新方法;在此基础上逐步建立起微塑料的动力模型和生态风险评价模型;探索海洋微塑料污染的应对方法。 相似文献
7.
海洋沉积物中的甲烷代谢微生物是甲烷循环的关键参与者，其代谢过程对大气甲烷浓度及全球气候变化具有显著影响，研究其在全球大洋沉积物中的组成及分布特征是探究微生物介导甲烷循环的基础。采用焦磷酸454高通量测序测定甲烷代谢保守功能基因mcrA(Methyl coenzyme–M reductase A)分析全球大洋沉积物中甲烷代谢微生物群落的组成和多样性；结合荧光实时定量PCR技术检测了古菌和甲烷代谢古菌的丰度分布特征。与其他海洋生境对比，大洋沉积物中甲烷代谢古菌群落结构单一，大西洋和印度洋的α多样性指数显著高于太平洋(p<0.05)。在大洋沉积物样品中鉴定到3个目的甲烷代谢古菌，即甲烷杆菌目(Methanobacteriales)、甲烷八叠球菌目(Methanosarcinales)和甲烷微菌目(Methanomicrobiales)，其中甲烷微菌目占绝对优势，并主要由一簇未知类群(暂名Oceanic Sediments Dominant group,OSD group)组成。大洋沉积物的古菌16S rRNA基因丰度(湿重，下同)平均为8.81×106 copie... 相似文献
8.
本文重点介绍海洋专项的科学意义、聚焦的关键问题、研究区域的选择、总体研究思路、实施方案与预期成果。海洋专项面向国家重大战略需求和国际海洋科技前沿,以西太平洋及其邻近海域海洋系统为主要研究对象,从"海洋系统"的视角开展综合性协同调查与研究,在西太暖池对东亚及我国气候的影响机制、邻近大洋影响下的近海生态系统演变规律、西太平洋深海环境和资源分布特征等领域开展系统研究,同时进行我国深海研究探测装备的研发与应用,为提升我国深海大洋理论研究水平,为我国海洋环境信息保障、战略性资源开发、海洋综合管理、防灾减灾、海上丝绸之路建设提供科学依据,为建设"海洋强国"提供科技支撑。 相似文献
9.
海洋微塑料来源、分布及生态效应研究进展 总被引：1，自引：0，他引：1
微塑料广泛分布于世界范围内的大洋和近海海域。作为新兴的污染物，微塑料对海洋生态环境威胁巨大。微塑料可以直接或间接被海洋动物摄入，导致其生长减缓或停滞、繁殖被抑制、寿命减短、进食量降低、耗氧量以及酶活性改变。微塑料与海洋浮游植物相互作用会对其生长、光合作用、氧化应激能力等产生影响。然而，微塑料对海洋浮游植物的致毒机理尚未完全明朗，还需更多的相关研究以探明其毒性效应机制。为保护海洋环境安全，更好的治理微塑料污染问题，有必要加强微塑料的相关研究，同时采取一系列有力的政策法规来监管塑料及微塑料的使用。 相似文献
10.
深海沉积物蕴藏了丰富的古海洋环境变化信息.利用沉积物中的某种替代指标,有效地恢复古海洋环境变化历史是海洋地球化学家和古海洋学家致力研究的课题.海洋系统中Ba元素的地球化学行为及其与古海洋环境的关系研究表明,深海沉积物中Ba元素的丰度和变化特征能够很好地揭示古海洋环境变化信息.根据海洋系统中Ba元素地球化学研究的最新进展,系统归纳了深海沉积物中Ba的来源、富集相态及其在早期成岩过程中的行为,并在此基础上,探讨了沉积物中Ba元素丰度变化特征与古生产力和沉积物中甲烷释放通量的关系. 相似文献
11.
八放珊瑚广泛分布在近岸浅海到深海，以及热带、温带甚至寒带等高纬度海区，在维持海洋生态系统结构完整性和生物多样性方面发挥了重要作用。受气候变化和人类活动影响，八放珊瑚呈现不断衰退趋势，忽视海洋生态系统原生物种自然禀赋的现象明显，尤其是八放珊瑚可供头足类产卵附着的生态功能尚未引起足够重视。本文综合梳理了八放珊瑚的结构和分类、繁殖特性和生殖方式、影响生态因子和退化原因等研究现状和问题，提出针对性保护和修复八放珊瑚的对策与建议，以期为我国重要生态系统保护和修复重大工程的实施提供基础资料。 相似文献
12.
Overview of eutrophication indicators to assess environmental status within the European Marine Strategy Framework Directive 总被引：1，自引：0，他引：1
João G. Ferreira Jesper H. Andersen Angel Borja Suzanne B. Bricker Jordi Camp Margarida Cardoso da Silva Esther Garcés Anna-Stiina Heiskanen Christoph Humborg Lydia Ignatiades Christiane Lancelot Alain Menesguen Paul Tett Nicolas Hoepffner Ulrich Claussen 《Estuarine, Coastal and Shelf Science》2011
13.
Suam Kim Chang-Ik Zhang Jin-Yeong Kim Jae-Ho Oh Sukyung Kang Jae Bong Lee 《Ocean Science Journal》2007,42(3):179-192
Understanding in climate effects on marine ecosystem is essential to utilize, predict, and conserve marine living resources
in the 21s t century. In this review paper, we summariz ed t h e past history and current status of Korean fisheries as well
as the changes in climate and oceanographic phenomena since the 1960s. Ocean ecosystems in Korean waters can be divided into
three, based on the marine commercial fish catches; the demersal ecosystem in the Yellow Sea and the East China Sea, the pelagic
ecosystem in the Tsushima Warm Current from the East China Sea to the East/Japan Sea, and the demersal ecosystem in the northern
part of the East/Japan Sea. Through the interdisciplinary retrospective analysis using available fisheries, oceanographic,
and meteorological information in three important fish communities, the trend patterns in major commercial catches and the
relationship between climate/ environmental variability and responses of fish populations were identified. Much evidence revealed
that marine ecosystems, including the fish community in Korean waters, has been seriously affected by oceanographic changes,
and each species has responded differently. In general, species diversity is lessening, and mean trophic level of each ecosystem
has decreased during the last 3~4 decades. Future changes in fisheries due to global warming are also considered for major
fisheries and aquaculture in Korean waters. 相似文献
14.
海洋浮游异养细菌(以下称浮游细菌)存在个体间的异质性,对浮游细菌异质性的研究是理解细菌生产、代谢及其在生物地球化学循环中重要作用的基础。流式细胞术具有快速分析大量细菌个体的能力,除了用来分析样品中细菌的丰度外,流式细胞术和细胞染色技术结合,被用来研究自然海水中浮游细菌在细胞膜完整性、CTC(5-氰基-2,3-二(4-甲基苯基)四唑氯化物)呼吸功能和核酸含量三个方面的异质性。尽管国外已经有较多研究,但我国在这方面的研究尚比较缺乏,本文综述了自然海区浮游细菌这三项异质性的研究现状,介绍了不同海区(主要是近岸)浮游细菌的异质性及其随环境的变化,以期推动我国在此领域的研究工作。目前对其异质性的变化机制尚没有很好的理论解释,在全球变化的大背景下,针对大洋深海和极区,有关长期变化、全球变暖以及酸化等对浮游细菌异质性的影响研究需要加强。 相似文献
15.
Shizuo Tsunogai 《Journal of Oceanography》1984,40(4):314-322
Since 1960 when I was a senior student, I have studied natural phenomena observed in the hydrosphere and atmosphere by means
of chemical elements. Each of the phenomena is, in general, very complicated and so I have attempted to depict the whole picture
of material circulation in the marine environment by studying its various aspects at the same time. My chief strategy has
been to use natural radio-nuclides as clocks of various phenomena, and to use sediment traps for the determination of vertical
fluxes in the ocean. The many results I have obtained can be summarized as follows.
1. I have found that several sporadic events control the material exchange through the atmosphere. These include the strong
winter monsoon and typhoons that transport sea-salt particles to the Japanese Islands, theKosa episodes that transport soil dust to the ocean, and storms that result in exchange of sparingly soluble gases such as oxygen
and carbon dioxide at the air-sea interface. I have also proved quantitatively that the source of aluminosilicate material
in pelagic sediments is air-borne dust.
2. I have proposed a model,Settling model, for the removal of chemical substances from the ocean and found various lines of evidence supporting the model. This model
predicts the reversibility in the existing state of insoluble chemical elements in seawater among large settling particles,
small suspended particles and colloidal particles that pass through a membrane filter and explains well their behavior in
the ocean. I have first precisely measured calcium and iodine in the ocean and have explained their distributions on the basis
of the solution and redox equilibria.
3. Using chemical tracers, I have estimated the vertical eddy diffusion coefficients to be 1.2 cm2sec−1 for the Pacific deep water, 0.5 cm2sec−1 for the deep Bering Sea water and 3–80 cm2sec−1 for the Pacific surface water, and have studied the structure of water masses in the western North Pacific and the Sea of
Japan. I have also invented and applied a method for the calculation of the age of deep waters using radiocarbon.
4. I have calculated the rates of decomposition of organic matter and the regeneration rates of chemical components in the
deep and bottom waters as well as coastal waters by modelling water circulation and mixing. Particulate fluxes and regeneration
rates are larger in the deep waters beneath the more biologically productive surface waters. I have stressed the role of silicate
in the marine ecosystem, especially in the succession of phytoplankton species.
5. I have quantitatively studied the migration of chemical elements during the early diagenesis of bottom sediments especially
manganese using chemical and radiochemical techniques. Manganese is being actively recycled not only in coastal seas but also
in pelagic sediments except in the highly oligotrophic subtropical ocean. This recycling can explain the formation of manganese
nodules and enables us to balance the manganese budget in the ocean. 相似文献
16.
The purpose of this study was to examine the distribution, abundance and characteristics of plastic particles in plankton samples collected routinely in Northeast Pacific ecosystems, and to contribute to the development of ideas for future research into the occurrence and impact of small plastic debris in marine pelagic ecosystems. Plastic debris particles were assessed from zooplankton samples collected as part of the National Oceanic and Atmospheric Administration's (NOAA) ongoing ecosystem surveys during two research cruises in the Southeast Bering Sea in the spring and fall of 2006 and four research cruises off the U.S. west coast (primarily off southern California) in spring, summer and fall of 2006, and in January of 2007. Nets with 0.505 mm mesh were used to collect surface samples during all cruises, and sub-surface samples during the four cruises off the west coast. The 595 plankton samples processed indicate that plastic particles are widely distributed in surface waters. The proportion of surface samples from each cruise that contained particles of plastic ranged from 8.75 to 84.0%, whereas particles were recorded in sub-surface samples from only one cruise (in 28.2% of the January 2007 samples). Spatial and temporal variability was apparent in the abundance and distribution of the plastic particles and mean standardized quantities varied among cruises with ranges of 0.004-0.19 particles/m3, and 0.014-0.209 mg dry mass/m3. Off southern California, quantities for the winter cruise were significantly higher, and for the spring cruise significantly lower than for the summer and fall surveys (surface data). Differences between surface particle concentrations and mass for the Bering Sea and California coast surveys were significant for pair-wise comparisons of the spring but not the fall cruises. The particles were assigned to three plastic product types: product fragments, fishing net and line fibers, and industrial pellets; and five size categories: <1 mm, 1-2.5 mm, >2.5-5 mm, >5-10 mm, and >10 mm. Product fragments accounted for the majority of the particles, and most were less than 2.5 mm in size. The ubiquity of such particles in the survey areas and predominance of sizes <2.5 mm implies persistence in these pelagic ecosystems as a result of continuous breakdown from larger plastic debris fragments, and widespread distribution by ocean currents. Detailed investigations of the trophic ecology of individual zooplankton species, and their encounter rates with various size ranges of plastic particles in the marine pelagic environment, are required in order to understand the potential for ingestion of such debris particles by these organisms. Ongoing plankton sampling programs by marine research institutes in large marine ecosystems are good potential sources of data for continued assessment of the abundance, distribution and potential impact of small plastic debris in productive coastal pelagic zones. 相似文献
17.
18.
Olafur S. Astthorsson Astthor Gislason Steingrimur Jonsson 《Deep Sea Research Part II: Topical Studies in Oceanography》2007,54(23-26):2456
This paper describes the main features of the Icelandic marine ecosystem and its response to climate variations during the 20th century. The physical oceanographic character and faunal composition in the southern and western parts of the Icelandic marine ecosystem are different from those in the northern and the eastern areas. The former areas are more or less continuously bathed by warm and saline Atlantic water while the latter are more variable and influenced by Atlantic, Arctic and even Polar water masses to different degrees. Mean annual primary production is higher in the Atlantic water than in the more variable waters north and east of Iceland, and higher closer to land than farther offshore. Similarly, zooplankton production is generally higher in the Atlantic water than in the waters north and east of Iceland. The main spawning grounds of most of the exploited fish stocks are in the Atlantic water south of the country while nursery grounds are off the north coast. In the recent years the total catch of fish and invertebrates has been in the range of 1.6–2.4 million ton. Capelin (Mallotus villosus) is the most important pelagic stock and cod (Gadus morhua) is by far the most important demersal fish stock. Whales are an important component of the Icelandic marine ecosystem, and Icelandic waters are an important habitat for some of the largest seabird populations in the Northeast Atlantic.In the waters to the north and east of Iceland, available information suggests the existence of a simple bottom-up controlled food chain from phytoplankton through Calanus, capelin and to cod. Less is known about the structure of the more complex southern part of the ecosystem. The Icelandic marine ecosystem is highly sensitive to climate variations as demonstrated by abundance and distribution changes of many species during the warm period in the 1930s, the cold period in the late 1960s and warming observed during the recent years. Some of these are highlighted in the paper. 相似文献