海水中酚类有机物在粘土或沉积物上吸附特性的模拟研究

研究了海水中７种酚类有机污染物在粘土矿物及海洋沉积物上的吸附特征;发现了酚在粘土或沉积物上的吸附平衡常数与其水溶解度之间的线性自由能关系,。     

海洋生态环境承载能力评价方法验证及建议 ——以浙江省近岸海域为例

为推动海洋资源的合理开发和有效保护,文章采用《资源环境承载能力监测预警技术方法(试行)》(《技术方法》)开展浙江省近岸海域海洋生态环境承载能力评价试点研究,验证指标体系和评价方法的适用性并提出建议。研究结果表明:《技术方法》的海洋环境承载状况评价结果更多代表氮磷水平,不足以客观反映海洋环境承载状况,而适应性验证方法的评价结果总体略好;海洋生态承载状况评价的适应性验证方法增加浮游植物参数,并以区域5年均值为基准,所得结果更为合理。针对《技术方法》的适用性问题以及业务化应用和管理的需求,建议:评价指标和具体参数的设置应考虑区位特点和自然属性,在海洋生态承载状况评价参数中增加浮游植物,并加长区域基准值的时间跨度;在集成评价时对指标设置较为合理的权重系数;加强中小尺度海洋生态环境承载能力研究;强化海洋生态环境承载能力评价与监测预警的结合应用。该研究成果可为进一步完善国家海洋生态环境承载能力监测预警工作提供技术支撑。     

海洋倾倒区对附近海域环境影响分析 ——以嵊泗上川山为例

文章根据2016—2017年3个航次的嵊泗上川山疏浚物海洋倾倒区跟踪监测资料,分析了倾倒活动对该海域的水下地形、水质、沉积物、生物的影响情况。结果表明：倾倒区局部区域出现一定的淤积态势,平均淤积厚度为0.13 m;疏浚物倾倒过程中,海水中的悬浮物、无机氮和磷酸盐含量明显增加,沉积物中的硫化物和镉有所增加;倾倒结束后水质、沉积物和生物都恢复至倾倒前水平。长期来看,受倾倒活动影响较大的是底栖生物,其生物量和栖息密度较本底值都明显降低。     

An energy conversion system based on deep-sea pressure

A novel seawater pressure energy conversion system that utilizes seawater pressure to generate electricity has been studied in this paper. The energy conversion system utilizes the pressure difference between the pressurized seawater and the empty pressure container to drive hydraulic motor and the coaxially coupled generator to generate electric power. The output electric energy is recorded by the data logger throughout the process. In the current study, technical analysis is performed with the emphasis on conversion efficiency between seawater pressure energy and output electric energy. The analysis is conducted at various pressure differences through the throttle valve so as to obtain maximum conversion efficiency. Research shows that the optimum pressure difference through the throttle valve and the maximum conversion efficiency can be theoretically calculated when the properties of the conversion system are given. Simulation results have demonstrated the influence of pressure difference on conversion efficiency. The test apparatus has been designed, built and tested in 2004. It successfully generated electric energy of approximately 0.85 kW h at the depth of 2400 m with empty pressure container's holding capacity of 200 L in the voyage “DY105-16” in South China Sea on June 12, 2004. The actual conversion efficiency from seawater pressure energy to electric energy reaches as high as 63.8% which is attractive for underwater equipments. The success of the experiment has tested the feasibility of utilizing seawater pressure energy and brings a new power supply way for long-term in-situ underwater equipments.     

硫酸盐还原菌对海水状态和碳钢腐蚀行为的影响

采用溶液环境参数和电极电化学参数测量技术研究了海水中硫酸盐还原菌生长和衰亡过程对溶液状态和D36碳钢腐蚀过程的影响。结果表明,硫酸盐还原菌通过新陈代谢作用把溶液中的硫酸盐转化为硫离子而增大了氧化还原电位和酸度,并导致D36钢的腐蚀电位负移和腐蚀速度增加。极化曲线和电化学阻抗谱证实,虽然金属腐蚀过程在上述过程中并未发生机理性变化,但阳极过程和部分阴极过程的加速是腐蚀速度增加的主要原因。上述结果同时表明．硫酸盐还原菌本身和新陈代谢中间体并未直接参与腐蚀过程,主要是通过产生的硫离子改变溶液状态来加速腐蚀过程的。     

The use of bromide and chloride mass ratios to differentiate salt-dissolution and formation brines in shallow groundwaters of the Western Canadian Sedimentary Basin

In the Western Canadian Sedimentary Basin, the petroleum industry handles two geochemically distinctive brines that are traceable in the environment: formation brines extracted along with hydrocarbons from the basin, and salt-dissolution brines, produced by dissolving deep halite formations to create caverns for petroleum product storage. The concentrations of the conservative ions chloride (Cl) and bromide (Br) in many formation brines plot closely to the seawater evaporation trajectory of previous studies. These brines contain Cl/Br mass ratios of around 300, while salt-dissolution brines are relatively Br depleted, having Cl/Br mass ratios in excess of 20,000. An oilfield site in central Alberta had experienced nearby releases of both salt-dissolution and formation brines. Geochemical mixing trends were defined by theoretically mixing samples of local salt-dissolution and formation brine sources with background shallow groundwater. Most site monitoring wells and local surface water samples plotted directly on a salt-dissolution brine dilution trend, while results from four monitoring wells, all located directly downgradient of formation brine spills, suggested the mixing of formation brines into shallow groundwater. This work indicates that there is a large-scale salt-dissolution brine plume beneath the site and reinforces the use of Cl and Br concentrations and mass ratios as environmental tracers.     

Status of butyltin pollution along the coasts of western Japan in 2001, 11 years after partial restrictions on the usage of tributyltin

Restrictions on the use of tributyltin (TBT) in aquaculture and on boats in coastal regions, except for ocean-going vessels, have been in place in Japan since 1990 due to the strong toxic effects of TBT on marine organisms. However, TBT pollution along the Japanese coasts has been reported after this legislation was enacted. In order to elucidate the present status of contamination by butyltin (BT) compounds, we measured the levels of BTs [monobutyltin (MBT), dibutyltin (DBT) and TBT] in seawater and Caprella spp. samples obtained from the western part of Seto Inland Sea, Uwa Sea and Uranouchi Bay in western Japan during March to September, 2001. Butyltins were detected in more than 90% of the seawater samples (n = 59), with average concentrations of 8.2 ± 9.2 (SD) ng MBT L⁻¹, 3.3 ± 3.0 ng DBT L⁻¹ and 9.0 ± 7.0 ng TBT L⁻¹. Among 41 stations situated on coastal lines, a sufficient number of Caprella organisms for chemical analysis could be collected from only 16 stations. The butyltin concentrations in seawater and Caprella samples from Uwa Sea and Uranouchi Bay, in which the dominant industry in both waters is aquaculture, showed significantly higher than or no significant differences from those samples from the western part of Seto Inland Sea, a major heavy-industry area in Japan. As the TBT concentration in seawater increased, the number of Caprella organisms collected decreased. The mean TBT concentration among the seawater samples was above the estimated lowest observable effect concentration (LOEC) that reduces the survival rate of Caprella danilevskii. Thus, the present study indicates that TBT is still a potential ecological hazard to the survival of marine invertebrates inhabiting coasts along western Japan, even 11 years after the partial ban on TBT usage was implemented.     

烟台四十里湾海区栉孔扇贝同化率周年变化及其与环境的关系

于１９９７年６月－１９９８年５月用现场方法测定了烟台四十里湾海区总颗粒物质（ＴＰＭ）、颗粒有机物（ＰＯＭ）现存量和栉孔扇贝同化率（ＡＥ）周年变化,并分析栉孔扇贝同化率与海区温度、盐度、ＴＰＭ和ＰＯＭ的关系。结果表明,（１）整个海区ＴＰＭ现存量秋季最高,其次为春季和冬季,夏季最低;海区ＰＯＭ含量变化不大,在１．３４－１．６５ｍｇ／Ｌ之间;栉孔扇贝同化率在春、夏、秋三了较高,冬季较低,其中在秋末冬初（     

Intercomparison of shipboard and moored CARIOCA buoy seawater fCO2 measurements in the Sargasso Sea

The ocean is an important sink for carbon and heat, yet high-resolution measurements of biogeochemical properties relevant to global climate change are being made only sporadically in the ocean at present. There is a growing need for automated, real-time, long-term measurements of CO₂ in the ocean using a network of sensors, strategically placed on ships, moorings, free-drifting buoys and autonomous remotely operated vehicles. The ground-truthing of new sensor technologies is a vital component of present and future efforts to monitor changes in the ocean carbon cycle and air–sea exchange of CO₂.A comparison of a moored Carbon Interface Ocean Atmosphere (CARIOCA) buoy and shipboard fugacity of CO₂ (fCO₂) measurements was conducted in the western North Atlantic during two extended periods (>1 month) in 1997. The CARIOCA buoy was deployed on the Bermuda Testbed Mooring (BTM), which is located 5 km north of the site of the US Joint Global Ocean Flux Study (JGOFS) Bermuda Atlantic Time-series Study (BATS). The high frequency of sampling revealed that temperature and fCO₂ responded to physical forcing by the atmosphere on timescales from diurnal to 4–8 days. Concurrent with the deployments of the CARIOCA buoy, frequent measurements of surface fCO₂ were made from the R/V Weatherbird II during opportunistic visits to the BTM and BATS sites, providing a direct calibration of the CARIOCA buoy fCO₂ data. Although, the in situ ground-truthing of the CARIOCA buoy was complicated by diurnal processes, sub-mesoscale and fine-scale variability, the CARIOCA buoy fCO₂ data was accurate within 3±6 μatm of shipboard fCO₂ data for periods up to 50 days. Longer-term assessments were not possible due to the CARIOCA buoy breaking free of the BTM and drifting into waters with different fCO₂-temperature properties. Strategies are put forward for future calibration of other in situ sensors.     

Assessment of the Intake and the Pretreatment Design in Existing Seawater Reverse Osmosis (SWRO) Plants by Hasse Diagram Technique (HDT)

Seawater desalination is a rising technology intended to overcome water scarcity and is increasingly being used for the production of drinking water. A good quality pretreatment process is prominent to the successful operation of a Seawater Reverse Osmosis (SWRO) plant. The tasks of the intake and the pretreatment modules are to prevent fouling and to extend the lifetime of the reverse osmosis membranes. To practice the method of assessment design, 19 seawater plants with 11 different design strategies have been evaluated. The assessed strategies consist of: (i) Intake treatment, (ii) pretreatment aid (coagulation, flocculation, clarification), and (iii) pretreatment unit. Every possible combination of the design elements has been evaluated by a set of 15 attributes. The comparative evaluation has been conducted by Hasse diagram technique (HDT) using PyHasse software. The result of the HDT application includes 7 favorable incomparable design strategies. In order to solve the incomparability, the Condorcet–Kemeny–Young–Levenglick (C–K–Y–L) ranking procedure was additionally used and rendered the optimal design that is based on subsurface intake and membrane (ultrafiltration) pretreatment facilities. According to the results, both mathematical methods, i.e., the HDT in combination with the C–K–Y–L, procedure can be powerful and helpful tools to assist decisions concerning design strategies.