严酷海洋大气环境下玻璃纤维复合材料腐蚀老化规律研究

目的 研究严酷海洋大气环境下,玻璃纤维增强树脂基复合材料的腐蚀老化规律.方法 通过实海大气环境试验,分析了南海岛礁大气环境下,复合材料暴露不同周期后的腐蚀形貌特征以及力学性能变化规律,建立了腐蚀老化性能预测灰色模型GM(1,1),并与青岛、厦门和三亚等典型海洋大气环境进行对比研究.结果 随暴露时间的增长,南海岛礁大气环境下的复合材料发生严重的纤维裸露,其弯曲强度呈下降趋势,基于弯曲强度建立的灰色模型GM(1,1)精度达到1级;与其他典型海洋大气环境相比,随着纬度的降低,复合材料的弯曲强度呈下降趋势.结论 灰色模型GM(1,1)对复合材料在岛礁等严酷海洋大气环境下的腐蚀老化性能预测精度较高.影响复合材料性能的最主要环境因素为辐照,其次为相对湿度和温度.     

纳氏试剂比色法直接测定海水中的氨氮

用纳氏试剂比色法直接测定海水中的氨氮 ,着重进行了酒石酸钾钠—氢氧化钠为掩蔽剂的方法条件试验。方法检出范围为 0 .0 5～ 2 .0 0mg L ,方法相对盐度范围为 10～ 3 2的海水可以直接测定     

渤海表层沉积物中多环芳烃的分布与生态风险评价

利用第2次全国海洋污染基线调查数据，研究渤海表层沉积物中多环芳烃(PAHs)的空间分布特征和输入来源．结果表明，按渤海海区划分，PAHs含量由高至低依次为秦皇岛沿岸、辽东湾、莱州湾、辽东半岛近岸、外海海区和渤海湾近岸．对照有关的沉积物质量标志水平，秦皇岛沿岸和辽东湾(尤其是锦州湾)表层沉积物中PAHs具有较高生态风险．就PAHs组成而言，锦州湾近岸沉积物中低环比例较高，其它海区4～5环占优．荧蒽／芘和芘／苯并(a)芘两个比值参数显示锦州湾近岸沉积物的PAHs主要源于石油工业，秦皇岛近岸和莱州湾部分站点主要来自燃油产物，而其它海区的大部分站点则属于燃煤型来源．燃烧生成的PAHs易吸附于细微颗粒物上，其迁移和沉降可能是外海海区PAHs含量高于渤海湾近岸的一个原因．     

夏季黄渤海表层海水中二甲亚砜(DMSO)的浓度分布

根据2011年6月对黄渤海进行的大面调查,分析研究了夏季表层海水中颗粒态和溶解态二甲亚砜(DMSOp、DMSOd)的水平分布及其周日变化特征.海水中DMSO首先采用NaBH4将其还原为二甲基硫(DMS),再利用冷阱吹扫-捕集气相色谱法进行间接测定.结果表明,表层海水中DMSOp浓度的变化范围是5.43～18.35 nmol·L-1,平均值为(11.47±0.25)nmol·L-1;DMSOd浓度的变化范围是4.75～43.80 nmol·L-1,平均值为(13.42±0.58)nmol·L-1.相关性分析显示:DMSOp与叶绿素a(Chl-a)、温度、盐度等不存在相关性,而DMSOp/Chl-a比值与盐度存在一定的正相关,表明DMSO在藻细胞内具有渗透压调节功能;DMSOd与细菌、DMSOp浓度不存在相关性,而与DMS浓度存在一定的正相关,表明表层海水中DMSOd的主要来源是DMS的光化学氧化.另外,DMSOp与DMSOd均呈现出明显的周日变化规律,白天时段浓度明显高于夜间时段.     

Sediment-associated aliphatic and aromatic hydrocarbons in coastal British Columbia, Canada: concentrations, composition, and associated risks to protected sea otters

Sediment-associated hydrocarbons can pose a risk to wildlife that rely on benthic marine food webs. We measured hydrocarbons in sediments from the habitat of protected sea otters in coastal British Columbia, Canada. Alkane concentrations were dominated by higher odd-chain n-alkanes at all sites, indicating terrestrial plant inputs. While remote sites were dominated by petrogenic polycyclic aromatic hydrocarbons (PAHs), small harbour sites within sea otter habitat and sites from an urban reference area reflected weathered petroleum and biomass and fossil fuel combustion. The partitioning of hydrocarbons between sediments and adjacent food webs provides an important exposure route for sea otters, as they consume ∼25% of their body weight per day in benthic invertebrates. Thus, exceedences of PAH sediment quality guidelines designed to protect aquatic biota at 20% of the sites in sea otter habitat suggest that sea otters are vulnerable to hydrocarbon contamination even in the absence of catastrophic oil spills.     

Long-term change of the marine environment and plankton in the Xiamen Sea under the influence of climate change and human sewage

ABSTRACT

Long-term observations of the Xiamen Sea in Fujian Province were used to analyze variations in sea temperature, salinity, inorganic nitrogen (N), activated phosphate (P), and phytoplankton, as well as the features of red tides. Results showed that in recent decades, sea temperature and concentrations of N and P nutrients increased while salinity decreased attributed to climate warming, rainfall, and human sewage. In addition, reduction in the number of phytoplankton species and rising abundance of phytoplankton indicated that the structure of phytoplankton community presented a simplified and minimized trend which magnified the dominance of dominant phytoplankton species. Since 2000, red tides have occurred more frequently, and the eutrophic-type diatom species, Skeletonema costatum appears to be the predominant species. Data suggested that variations of N and P nutrients exert a potent and rapid influence on phytoplankton than sea temperature and ocean salinity.     

现代中国海平面变化规律及发展趋势的初步分析

本文根据对大量实际观测资料的统计分析认为:中国区域海面里缓慢上升趋势,在此背景下,不同地区升降趋向和幅度差异巨大;控制海面变化的因素具有多元化特点;在今后数十年内,气候和海平面的自然变化不剧烈,温室效应所引起的海平面上升幅度不超过1～2mm/a。     

Chlorinated Hydrocarbons in Surface Sediments From the Open Adriatic

This paper presents the results of the examination of concentrations of chlorinated hydrocarbons in surface sediments from the middle of the Adriatic. the sampling area was chosen as part of the protection programme of the Adriatic Sea and is located at two transverse transects, each consisting of four stations. the sediments were collected during the summer cruise of 1990. Quantification of individual components was performed by Capillary Gas Chromatography (CGC) using reference standards. Areal distribution of the concentrations of HCB, lindane, DDT and its metabolites, dieldrin, endrin and PCBs are presented. the values obtained varied within a wide range of concentration from 20 pg/g dry weight for lindane to 700 pg/g dry weight for Σ DDT and the sum of PCBs as Aroclor 1254 from 0.3 to 6.6 ng/g.

The main source of these compounds is thought to be from suspended matter entering the Adriatic sea via the River Po and transported by currents to its middle part.     

Greenhouse effect and coastal wetland policy: How Americans could abandon an area the size of Massachusetts at minimum cost

Climatologists generally expect an anthropogenic global warming that could raise sea level 30–150 cm in the next century and more thereafter. One of the impacts would be the loss of coastal wetlands. Although the inundation of adjacent dryland would enable new wetlands to form, much of this land is or will soon be developed. If developed areas are protected, wetlands will be squeezed between an advancing sea and the land being protected, which has already happened in China and the Netherlands, where people have built dikes for centuries. Unlike those countries, the United States has enough land to accommodate the landward migration of wetlands; but governments lack the funds to purchase all the coastal lowlands that might be inundated and the legal authority to prohibit their development. We propose a third approach: allowing property owners to use coastal lowlands today as they choose, but setting up a legal mechanism to ensure that the land is abandoned if and when sea level rises enough to inundate it. Although compensation may be required, this approach would cost less than 1% as much as purchasing the land, and would be (1) economically efficient by enabling real estate markets to incorporate expectations of future sea level rise; (2) constitutional by compensating property owners; and (3) politically feasible by pleasing people who care about the long-term fate of the coastal environment without disturbing people who either are unconcerned about the distant future or do not believe sea level will rise. This article demonstrates that it would be irrational to delay policy formulation until sea level rise projections are more precise. The cost will be small if we act now but great if we wait, and sea level is already rising along most coasts. The US government should develop a strategy in the next three years. The opinions expressed in this paper do not necessarily reflect the views of EPA and no official endorsement should be inferred.     

Marine Organisms as Indicators of Heavy Metal Pollution-Experience from 16 Years of Monitoring at a Lead Zinc Mine in Greenland

In monitoring the impact of a lead-zinc mine in Greenland, species of fish, prawns, seaweed and mussels have been analysed for cadmium, copper, lead and zinc for several years. These metals have been released to the marine environment in significant amounts from the mining operation.