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1.
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   

2.
Recently, the accumulation of plastic debris in the marine environment has become a great concern worldwide. Although plastics are biologically and chemically inert, plastic debris has been suspected of causing adverse effects on ecosystems due to the increase in reactivity by size reduction and/or micropollutants associated with plastics. Because of the high sorption capacity of microplastics toward organic micropollutants, it is suspected that microplastics may play roles in the distribution and fate of micropollutants. In order to quantitatively evaluate the “net flow” of environmental contaminants in water-plastic-organism systems, a fugacity analysis was conducted using concentrations of polycyclic aromatic hydrocarbons (PAHs) in open oceans and in polyethylene as a representative material of plastic debris. Ratio of fugacity in polyethylene to that in seawater showed a decreasing trend with increasing partition coefficient between polyethylene and seawater (KPE/sw). This indicates that phase equilibrium between polyethylene and seawater is not attained for higher molecular weight PAHs. Disequilibrium of high molecular weight PAHs suggests that transfer from seawater to plastic debris is thermodynamically driven and the role of plastic debris as a vector to transfer them to living organisms would be minimal. However, additives may slowly migrate from plastics into the environment causing potentially serious effects on ecosystems.  相似文献   

3.
The impacts of plastic debris on the marine environment have gained the attention of the global community. Although the plastic debris problem presents in the oceans, the failure to control land-based plastic waste is the primary cause of these marine environmental impacts. Plastics in the ocean are mainly a land policy issue, yet the regulation of marine plastic debris from land-based sources is a substantial gap within the international policy framework. Regulating different plastics at the final product level is difficult to implement. Instead, the Montreal Protocol may serve as a model to protect the global ocean common, by reducing the production of virgin material within the plastics industry and by regulating both the polymers and chemical additives as controlled substances at a global level. Similar to the Montreal Protocol, national production and consumption of this virgin content can be calculated, providing an opportunity for the introduction of phased targets to reduce and eliminate the agreed substances to be controlled. The international trade of feedstock materials that do not meet the agreed minimum standards can be restricted. The aim of such an agreement would be to encourage private investment in the collection, sorting and recycling of post-consumer material for reuse as feedstock, thereby contributing to the circular economy. The proposed model is not without its challenges, particularly when calculating costs and benefits, but is worthy of further consideration by the international community in the face of the global threats posed to the ocean by plastics.  相似文献   

4.
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   

5.
塑料污染已成为国际海洋界关注的海洋环境问题之一。文章探讨海洋环流对南海及其周边海域表层塑料颗粒交换的影响。在南海周边多个海域, 分别在4个季节投放塑料颗粒。一年后, 用拉格朗日颗粒示踪方法考察投放颗粒的运动轨迹和最终停留位置。结果表明, 在秋、冬季, 大部分塑料颗粒会进入南海和爪哇海, 极少部分颗粒北输送到太平洋; 在春、夏季, 仅有部分颗粒进入南海和爪哇海, 而多数颗粒流到太平洋。南海洋流具有季节特征, 塑料颗粒轨迹特征与之较为符合。  相似文献   

6.
It is widely documented that marine debris is detrimental to the marine ecological environment. While there are various sources of marine debris, that generated by ships constitutes a significant proportion. Annex V of MARPOL 73/78 is to regulate the discharge of garbage from ships; in particular, it prohibits all kinds of plastics from being discharged into ocean. However, most fishing vessels are virtually exempt from such regulations due to their low gross tonnage, below 400 t. Given the great number of fishing vessels operating around the world, it can be argued that fishing vessels are a common source of marine debris. This paper aims to propose measures that will fill the gap in international regulations in addressing the problem of vessel-source garbage pollution. An understanding of what constitutes the underlying causes leading to fishers' decision on debris disposal is needed when designing effective measures to reduce garbage pollution from ships. Thus, this paper seeks to identify factors that have the potential to influence fishers' disposal behavior and investigate the association between factors and fishers' intention of bringing garbage back to port. Major factors of a well-developed recycling practice, adequate collection facilities placed at port, fishers' positive views towards marine environments and provision of rewards are identified, which have significant implications for management strategies. Finally, the papers offers suggestions regarding future efforts focusing on debris reduction strategies to further address the problem of garbage pollution from fishing vessels.  相似文献   

7.
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   

8.
Marine pollution from plastic debris is a global problem causing negative impacts in the marine environment. Plastic marine debris as a contaminant is increasing, especially in Canada. While the impacts of macroplastics are well known in the literature, there are relatively few policy studies related to mitigating microplastic toxicity in the environment. Despite overwhelming evidence of the threat of plastic in the marine environment, there remains inadequate or limited policies to address their mitigation, particularly microplastic debris. Existing policies for waste management, marine debris monitoring and awareness campaigns were evaluated from other jurisdictions. Policies and recommendations were developed for the Canadian context. Recommendations include improved practices for: (1) law and waste management strategies; (2) education, outreach and awareness; (3) source identification; and (4) increased monitoring and further research.  相似文献   

9.
The potential threat of plastic pollution to seabirds within the Hauraki Gulf was assessed by determining its abundance and distribution at two different spatial scales and assessing the community of resident seabirds during July to September 2008. Samples of floating plastics within the gulf were taken during 66 trawls from the surface of the water in three regions within the inner gulf and Waitamata harbour. Within each of these regions, samples were taken in and outside of visually identified natural slick lines that are surface manifestations of small-scale convergence zones. During each trawl, the identity and abundance of seabirds were assessed. Plastic debris was recorded in all three regions sampled with the greatest abundance being recorded in the harbour. Plastics and debris were also significantly more concentrated within natural slick lines. Both user and industrial plastics were identified and consisted of colours and lengths likely to be mistaken as food items for small to medium seabirds. Surface or near-surface feeding seabirds in the gulf most likely mistakenly to consume plastics were fluttering shearwaters, Cape pigeons and Buller's shearwaters. However, these birds were most abundant in the area of the gulf where abundance of plastic pollution was lowest. The Hauraki Gulf is considered significantly less polluted by plastic debris than other severely polluted areas cited in literature.  相似文献   

10.
海洋微塑料污染现状及其对鱼类的生态毒理效应   总被引:3,自引:0,他引:3  
海洋微塑料污染已成为全球性环境问题,鉴于微塑料特殊的理化性质,其对海洋生物和海洋生态系统的生态效应愈发受到关注。本文在综述海洋微塑料来源、类型和分布状况的基础上,探讨了鱼类摄入微塑料的途径及其生态毒理学效应。研究表明,全球近岸、大洋和极地海域均有微塑料分布,我国微塑料污染亦较为严重。微塑料会对包括鱼类在内的海洋生物生存造成威胁,其被鱼类摄入的主要途径是经口误食,微塑料进入鱼体后可在不同组织和器官中迁移,消化道是主要蓄积器官。微塑料对海洋鱼类的生态毒理效应主要包括:(1)影响生殖与精卵发生;(2)降低存活率;(3)影响生长发育;(4)扰乱行为;(5)导致组织病变与炎症反应;(6)导致代谢紊乱;(7)干扰神经系统;(8)导致氧化应激;(9)干扰内分泌等。未来研究应重点关注微塑料在海洋生态系统中的迁移扩散过程、不同浓度和粒径微塑料对鱼类的生态毒理效应及致毒机制研究、微塑料和其他典型海洋污染物对鱼类的联合毒性效应,以及微塑料与海洋酸化、缺氧、升温等全球环境问题的叠加效应等。  相似文献   

11.
Coastal urban environments have high plastic pollution levels, and hence interactions between plastic debris and marine life are frequent. We report on plastic ingestion by mullet Mugil cephalus in Durban Harbour, KwaZulu-Natal, South Africa. Of 70 mullet (13.0–19.5?cm total length), 73% had plastic particles in their guts, with a mean of 3.8 particles per fish (SD 4.7). Plastic ingestion showed no relation to digestive tract content or fish length. White and clear plastic fibres were ingested most commonly. This urban population of M. cephalus had a higher incidence of plastic ingestion than has been reported in studies on fish from other coastal areas or the oceanic environment.  相似文献   

12.
塑料在环境中不断地积累,逐渐破碎成为尺寸小于5 mm的微塑料,对环境和人类健康构成严重威胁.本研究从青岛李村河口采集的塑料薄膜上分离出一株能够降解聚乙烯(PE)的细菌,命名为LC-2,通过分子生物学结合形态学和生理生化特征分析将其鉴定为芽孢杆菌(Bacillus aquimaris).在以PE为唯一碳源的液体培养基中,...  相似文献   

13.
The enrichment of marine particles with selenium cannot be explained as that with metals present in cationic form by complexation with anionic functional groups of adsorbed organic matter. Physicochemical data obtained using a model system are reported. The surface of the particles is modelized by a mercury electrode whose surface charge density can be easily changed, covered by a layer of adsorbed polymers. Studies with different kinds of macromolecules and salts show a specific interaction between adsorbed polyalanine and selenite. The results can be explained by the concordance of the distances between two oxygen atoms in this oxyanion and between two amine groups of the adsorbed polypeptide. A similar mechanism could occur in marine aggregates whatever their nature, as long as they contain amine groups at their surface which result in this concordance. Some prospects derived from the results are discussed.  相似文献   

14.
作为新型海洋污染物,海洋塑料垃圾入海通量计算过程中涉及的源汇过程、迁移途径、输运过程等尚未完全清楚,需进一步研究完善。以工业高速发展的厦门湾为研究对象,考虑潮流、入海径流、风等因素的影响,基于MIKE3软件的生物仿真模拟技术(Agent Based Modelling),模拟研究了漂浮及悬浮塑料垃圾的分布特征和迁移规律,并提出经验公式对沉积塑料垃圾的通量进行了预测。结果表明漂浮塑料垃圾在不利风、常风向和最大风的作用下集中堆积于岸线处。而悬浮塑料垃圾由海面向下呈现指数式下降的分布特征,且其水平迁移分布与潮流运动密切相关;流速小的区域悬浮塑料垃圾更容易堆积使局部浓度升高。悬浮塑料垃圾的扩散速率也与塑料颗粒的物理性质有关,沉降速度小的塑料颗粒在水中悬浮的时间更长,更容易被传输到距离污染源更远的地方。同时,研究发现沉积微塑料通量的增长规律近似为线性变化,通量大小与厦门塑料产量和厦门湾的水动力特性相关。  相似文献   

15.
This study aimed to assess the accumulation of small plastic debris in the intertidal sediments of the world's largest ship-breaking yard at Alang-Sosiya, India. Small plastics fragments were collected by flotation and separated according to their basic polymer type under a microscope, and subsequently identified by FT-IR spectroscopy as polyurethane, nylon, polystyrene, polyester and glass wool. The morphology of these materials was also studied using a scanning electron microscope. Overall, there were on average 81 mg of small plastics fragments per kg of sediment. The described plastic fragments are believed to have resulted directly from the ship-breaking activities at the site.  相似文献   

16.
The spatial distribution of small plastic debris on Heungnam beach in February 2011 was investigated. The abundances of small plastic debris over 2 mm in size along the high strandline and cross-sectional line of the beach were determined. The mean abundances of small plastics were 976 ± 405 particles/m2 at the high strandline in the upper tidal zone along the shoreline and 473 ± 866 particles/m2 at the cross-section perpendicular to the shoreline. Specifically, styrofoam (expanded polystyrene) spherules accounted for 90.7% of the total plastic abundance in the high strandline and 96.3% in the cross-section. The spatial distribution patterns of small plastic debris differed between the high strandline and cross-sectional line. The cross-sectional distribution of small plastic abundance differed among plastic types, indicating that representative sampling of small plastic debris on a beach is necessary.  相似文献   

17.
Sediment traps are an important tool for studying the source, composition and sedimentation processes of sinking particulate matter in the ocean. An in situ observational mooring(TJ-A-1) is located in the northern South China Sea(20.05°N, 117.42°E) at a water depth of 2 100 m and equipped with two sediment traps deployed at 500 m and 1 950 m. Samples were collected at 18-day intervals, and 20 samples were obtained at both depths from May 2014 to May 2015. Large amounts of fecal matter and marine snow were collected in the lower trap. The fluxes of marine snow and fecal pellets exhibited a fluctuating decrease between May 2014 and early August 2014 and then stabilized at a relatively low level. Scanning electron microscopy observations revealed that the main components of the marine snow and fecal pellets were diatoms, coccolithophores, radiolarians, and other debris, all of which are planktons mostly produced in photic zone. Used in conjunction with the particle collection range estimates from the lower trap and data on ocean surface chlorophyll, these marine snow and fecal pellets were related to the lateral transport of deep water and not vertical migrations from overlying water column. Moreover, the source area might be southwest of Taiwan.  相似文献   

18.
全球日益增多的海滩垃圾,不仅造成海洋环境污染,严重威胁海洋生态系统健康,也对生物栖息地有着不可估计的影响。如何高效准确地对海滩垃圾进行监测和识别,是处置海滩垃圾过程的技术难点之一。基于此,本文以长江口南汇边滩为实验区,通过在海滩上设置常见垃圾样品,随后利用激光雷达记录的全波形数据和BP神经网络模型,以快速鉴别海滩垃圾类型。结果表明:基于激光雷达提取的垃圾全波形数据中回波振幅和回波宽度的差异,可用来识别海滩垃圾。构建的BP神经网络可有效将海滩垃圾分为泡沫类、布类、金属类、纸类及塑料类,最高识别率达到79%。此外,由于不同材质海滩垃圾的原材料成分存在相似或同质,会对精确识别区分垃圾类型造成一定的干扰,从而影响神经网络的识别率。可见,将激光雷达应用于识别海滩垃圾,为海滩垃圾的监测提供了新的方法。  相似文献   

19.
塑料污染现象在世界各地海滩随处可见, 日益成为海洋环境中的重要威胁。文章调查了西沙海域甘泉岛和全富岛海滩的塑料污染分布情况, 结果显示, 尽管研究区域远离大陆, 人类活动影响较小, 但是海岛海滩上的塑料污染普遍存在, 塑料垃圾(>5mm)的平均分布丰度为(85.07±70.48)个∙m-2, 平均重量为(40.23±78.15)g∙m-2; 微塑料(<5mm)的平均分布丰度为(1774.75±1534.37)个∙m-2或(100.82±87.18)个∙kg-1。塑料垃圾和微塑料在不同海岛间的丰度分布均无显著性的差异, 但无论是塑料垃圾的丰度还是微塑料的丰度, 在环礁内侧海滩都显著高于环礁外侧海滩。此外, 微塑料的丰度分布与塑料垃圾的丰度分布呈显著的线性相关。红外光谱分析得出塑料聚合物主要成分有聚苯乙烯、聚丙烯和聚乙烯等, 其中以聚苯乙烯泡沫的比例占优。甘泉岛和全富岛海滩的塑料污染主要是通过其他地区的外源性塑料输送而来, 其在海岛上的不均匀空间分布受到区域海流作用、水动力条件、塑料降解等多种因素的影响。  相似文献   

20.
Reduction of marine debris requires knowledge of its sources. Sources of plastic marine debris found on six beaches of Korea were estimated. Samples larger than 25 mm were collected from 10 quadrats of 5 × 5 m for each beach in spring 2013. The total 752 items (12,255 g) of debris comprised fiber and fabric (415 items, 6,909 g), hard plastic (120 items, 4,316 g), styrofoam (93 items, 306 g), film (83 items, 464 g), foamed plastic other than styrofoam (21 items, 56 g), and other polymer (20 items, 204 g). With the probable sources allocated to each of 55 debris types, the source of 56% of all the collected debris appeared to be oceanbased and 44% was land-based. Priorities of policy measures to reduce marine debris should be different from regions to regions as the main sources of debris may differ.  相似文献   

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