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1.
Shipping is a vital industry for the global economy. Stability of ships, provided by ballast water, is a crucial factor for cargo loading and unloading processes. Ballast water treatment has practical significance in terms of environmental issues, ecosystem, and human health, because ships discharge this water into the environment before loading their cargos. This study reviews the common methods for ballast water management – exchange, heating, filtration, ultrasonic treatment, ultraviolet irradiation, chemicals, and gas supersaturation – to select the best one. This study compares water temperature, salinity, dissolved oxygen, polycyclic aromatic hydrocarbons (PAHs), and heavy metals (Co, Cr, Ni, Pb) for ballast tanks of selected ships with the recipient port environment in the Persian Gulf as a case study. The exchange of ballast water in the ocean and/or its treatment on board to prevent inadvertent effects on the environment's physicochemical conditions is related to vessel characteristics, legislation, and the environmental condition. Ecological risk study showed that the salt content in ballast water is close to that of seawater, but the values of Cr (2.1 mg/l) and Ni (0.029 mg/l) in ballast water are higher than those in seawater (1 and 0.004 mg/l, respectively).  相似文献   

2.
A prominent vector of aquatic invasive species to coastal regions is the discharge of water, sediments, and biofilm from ships' ballast-water tanks. During eight years of studying ships arriving to the lower Chesapeake Bay, we developed an understanding of the mechanisms by which invasive microorganisms might arrive to the region via ships. Within a given ship, habitats included ballast water, unpumpable water and sediment (collectively known as residuals), and biofilms formed on internal surfaces of ballast-water tanks. We sampled 69 vessels arriving from foreign and domestic ports, largely from Western Europe, the Mediterranean region, and the US East and Gulf coasts. All habitats contained bacteria and viruses. By extrapolating the measured concentration of a microbial metric to the estimated volume of ballast water, biofilm, or residual sediment and water within an average vessel, we calculated the potential total number of microorganisms contained by each habitat, thus creating a hierarchy of risk of delivery. The estimated concentration of microorganisms was greatest in ballast water>sediment and water residuals>biofilms. From these results, it is clear microorganisms may be transported within ships in a variety of ways. Using temperature tolerance as a measure of survivability and the temperature difference between ballast-water samples and the water into which the ballast water was discharged, we estimated 56% of microorganisms could survive in the lower Bay. Extrapolated delivery and survival of microorganisms to the Port of Hampton Roads in lower Chesapeake Bay shows on the order of 10(20) microorganisms (6.8 x 10(19) viruses and 3.9 x 10(18) bacteria cells) are discharged annually to the region.  相似文献   

3.
In examining ship-mediated biological invasions, most research and treatment development has focused on ballast water. Another vector that has gained attention recently is vessels arriving in a "no ballast on board" (NOBOB) condition. Such ships retain relatively small, unpumpable volumes of water and sediment in their ballast tanks. Nonetheless, these unpumpable portions can represent great ecological risk. This scenario is relevant in the Great Lakes, which have experienced a dramatic series of introductions, despite most vessels arriving there as NOBOBs since 1994. We examined shipping patterns of NOBOBs arriving to lower Chesapeake Bay to begin evaluating their risk of biopollution. Only 14% of ships arrive as NOBOBs, and of those, 17% depart to another port in the upper bay. Most NOBOBs arrive from or leave for other US ports; proximate trans-Atlantic crossings are few. Given the nature of their operations, we conclude NOBOBs may represent a risk for aquatic nuisance species invasions to Chesapeake Bay.  相似文献   

4.
Colony-forming eutrophic marine microorganisms in ballast water were counted in samples taken on board in 2002 and 2003. In the ballast water in Japan, viable cell numbers were highly variable but not by more than 10(5.1) colony-forming units (CFU)ml(-1) regardless of season. Even when ballast water was discharged offshore, values varied but not by more than 10(5.0) CFUml(-1). The effectiveness of the ballast water exchange was unconfirmed, except for the February 2003 voyage. No microbial colonies were counted in the reloaded ballast water in the high seas on that voyage, which contributed to the reduction of the total number of viable cells sampled in the discharged ballast water at the Ras Laffan port in Qatar. In sediment samples, the values of 10(5.2) - 10(6.0) CFUml(-1) were estimated for all seasons in which voyages took place. The maximum of the marine Vibrio species, 110 CFUml(-1), was observed in the ballast water sample taken in July 2003. The estimated total viable cell numbers in sediments were higher than those counted in the ballast water throughout the experiments, indicating the importance of sediment management as well as ballast water management on vessels traveling from Japan.  相似文献   

5.
The human mediated transfer of harmful organisms via shipping, specifically via ballast water transport, leading to the loss of biodiversity, alteration of ecosystems, negative impacts on human health and in some regions economic loss, has raised considerable attention especially in the last decade. Ballast water sampling is very important for biological invasions risk management. The complexity of ballast water sampling is a result of both the variety of organism diversity and behaviour, as well as ship design including availability of ballast water sampling points. Furthermore, ballast water sampling methodology is influenced by the objectives of the sampling study. In the course of research conducted in Slovenia, new sampling equipment for ships' ballast water was developed and tested. In this paper new ballast water sampling methods and equipment together with practical shipboard testing results are presented.  相似文献   

6.
The ongoing transfer of harmful organisms by shipping, especially via ballast water transport, may result in a change of biodiversity, alteration of ecosystems, negative impacts on human health and economic loss. Species introductions which cause irreversible consequences to receiving environments and economies call for particular attention. One critical issue is a need to evaluate the quantities and processes of species introductions. Consequently ballast water was sampled on 15 ships calling at the Port of Koper, Slovenia. This was the first ballast water sampling study in the Mediterranean Sea. This paper summarises the sampling results. Samples were analysed for all types of aquatic organisms including bacteria. The results may be considered as background information for an initial risk assessment of future species introductions - an important tool for the implementation of ballast water management measures.  相似文献   

7.
Ballast water exchange processes facilitate the dispersal and unnatural geographic expansion of phytoplankton, including harmful algal bloom species. From 2005 to 2010, over 45,000 vessels (≈ 8000 annually) travelled across Galveston Bay (Texas, USA) to the deep-water ports of Houston (10th largest in the world), Texas City and Galveston. These vessels (primarily tankers and bulkers) discharged ≈ 1.2 × 10(8) metrictons of ballast water; equivalent to ≈ 3.4% of the total volume of the Bay. Over half of the ballast water discharged had a coastwise origin, 96% being from US waters. Galveston Bay has fewer non-indigenous species but receives a higher volume of ballast water discharge, relative to the highly invaded Chesapeake and San Francisco Bays. Given the magnitude of shipping traffic, the role of Galveston Bay, both as a recipient and donor region of non-indigenous phytoplankton species is discussed here in terms of the invasibility risk to this system by way of ballast water.  相似文献   

8.
Ballast water exchange was measured for the first time in Bilbao Harbour, one of the most active of northern Spain. Between 1997 and 2006, 41,900,980.34 ballast water tn were loaded and 13,272,709 tn were discharged. Bilbao Harbour appears to be mainly a source of ballast water, 90% of which would be discharged in European harbours. We estimated that vessels carrying liquid and solid bulk have higher probabilities of exporting ballast water, whereas those with liquid bulk and containers are more likely to introduce it. From 30 potentially harmful phytoplankton species identified to date near harbour facilities, there would be a high risk of exporting at least Alexandrium minutum, Dinophysis sp., Heterosigma akashiwo, Karlodinium sp., Ostreopsis cf. siamensis, Pfiesteria-like and Prorocentrum minimum. Invasion risk by ballast water was tested by analyzing the response of six strains of H. akashiwo from different geographic areas to varying salinity. Results show that successful growth of foreign strains would be possible.  相似文献   

9.
A semi-quantitative risk assessment model for dispersion of ballast water organisms in shelf seas is applied to the Scotian Shelf region of eastern Canada. The ballast water exchange process is simulated as the dispersion of tracer released into the surface layer of an ocean circulation model of the region. Circulation model variability is driven by wind stress from a cyclical year of forcing representing climatological storminess. Dispersion metrics related to invasion risk are developed and incorporated into a risk equation that computes the relative overall risk of invasion for ballast water exchange segments along vessel tracks crossing the shelf. Three hundred and sixty dispersion simulations are done for each segment of each of six tracks. Because the flow fields represent climatological variability in shelf circulation, the application of the risk assessment model captures the expected variability in invasion risk. Model results indicate that more than an order of magnitude variation in risk can exist along a given vessel track, and that tracks with offshelf segments provide a lower risk option compared to onshelf tracks. The model provides quantitative guidance to regulators regarding what is an acceptable trip diversion and can aid in numerous other management decisions.  相似文献   

10.
湖泊生态水位计算新方法与应用   总被引：6，自引：4，他引：2  
淦峰  唐琳  郭怀成  高伟 《湖泊科学》2015,27(5):783-790
水位是湖泊水文情势的主要特征指标,对湖泊的水量、水质和生物的栖息地等有直接或间接的影响,被认为是湖泊生态系统健康的关键影响因素.如何确定合理的湖泊水位以保证生态系统健康成为湖泊科学研究的重要科学问题.根据湖泊天然水位情势,从天然水文变化中识别多项反映完整水位过程的指标,构建了湖泊生态水位的计算方法.从湖泊天然水位情势中提取出高、低水位的历时、发生时间和变化率等水位指数来表征其生态水位.该方法弥补了传统湖泊生态水位计算方法仅给出最小生态水位的不足,体现了湖泊生态系统健康对水位过程的要求.基于提出的生态水位计算方法和鄱阳湖都昌水位站1952-2000年共49年的日均监测数据,计算了鄱阳湖的生态水位目标值区间,以期为鄱阳湖水利工程生态调度提供决策依据.  相似文献   

11.
The proposed MTB is a process to expedite the implementation of international standards and regulations, and the subsequent testing, certification, and regulatory approval of new ballast water treatment ("control") technologies. This would expedite their acceptance in the global marketplace and reduce risks of shipowners following international regulation. The cost to test and evaluate and certify new ballast water treatment technologies for the global marketplace has been estimated to be less than US $1 per day per ship. It is time for the shipping industry, national regulatory bodies, and IMO to endorse the concept of the MTB and for the shipping industry to support a proactive cost-saving solution for sustainable shipping and protecting the environment from unwanted invasions of aquatic species with their potential negative impacts.  相似文献   

12.
Industrial pollution has caused serious human health risk because the pollutants can be accumulated in human body via multi routes in a long term, especially in areas of rapid industrialization. It is of great importance to obtain the pollutants’ information, including the transport routes and spatial distribution in the various environmental media of different sub-regions, to facilitate more accurate risk assessment and more effective risk management in urban ecosystems. In this article, we proposed a research framework of urban ecological risk assessment method, which combines the multimedia fugacity model, the multi-route exposure model, exposure-risk relationships and geographic information system (GIS). An urban ecological risk assessment of a hypothetical region indicates that it is possible and feasible to introduce GIS into the previous method to satisfy the requirements of risk management. The assessment results can be further utilized for industrial pollution emission control.  相似文献   

13.
《Marine pollution bulletin》2012,65(12):2742-2748
Ballast water has been identified as one of the key pathways for the movement of species between different ecosystems. The purpose of this study is to evaluate the biological efficacy and the potential toxicological impact of a proposed ballast water treatment using hydroxyl radicals as the main active substances. Living biomass of organisms kept in treated water for 2 days met the requirement stated in the International Maritime Organization (IMO) Ballast Water Convention (Regulation D-2), and no re-growth was observed over a period of 5 days. Aquatic toxicity tests of three trophic levels for the treated ballast water were performed. The results indicated that the toxicological risk of the discharge water to the receiving environment was not significant.  相似文献   

14.
Ballast water is a likely cause for worldwide transfer of non-indigenous aquatic species because of the large volumes and frequency of possible inoculations. Ozone is one treatment option being considered for eliminating non-indigenous species in ballast water. When ozone is applied to seawater, secondary disinfectants are formed, commonly measured and expressed as total residual oxidant (TRO). The goal of this study was to determine those variables most likely to affect the rate of TRO increase during ozonation and the subsequent TRO decline that occurs over time. These parameters strongly influence the efficacy of ozone treatments aimed to eliminate organisms present in ballast water. Seawater was obtained from Puget Sound, Washington; Cape Fear, North Carolina; and San Francisco Bay. Results indicated that seawater characteristics, including the organic content and ammonia, affect the amount of ozone required to achieve a desired TRO level and rate of TRO decay, and therefore need to be considered in determining ozone requirements for ballast water treatment.  相似文献   

15.
Many transoceanic vessels enter the Great Lakes carrying residual ballast water and sediment that harbours live animals and diapausing eggs. In this study, we examine the potential for sodium hypochlorite (NaOCl) to reduce the risk of species introductions from diapausing invertebrate eggs in residual ballast sediment. We collected sediment from three transoceanic vessels and from Lake Erie and exposed them to NaOCl concentrations between 0 and 10,000 mg/L for 24 h. Hatching success was reduced by >89% in all four experiments at 1,000 mg/L relative to unexposed controls. Fewer species hatched at high than at low NaOCl concentrations. Based on an average residual ballast of 46.8 tonnes, the volume of NaOCl required to treat inbound vessels is 374 L. Impacts of NaOCl use could be minimized by neutralization of treated residuals with sodium bisulfite. Further research is needed, however, to evaluate the effect of NaOCl on ballast tank corrosion.  相似文献   

16.
Data on shipping traffic in one of the busiest seaports in the world, the Port of Kaohsiung, were analyzed to evaluate the implications for ballast water management. Results show that 67% of the arriving vessels were registered to a flag of convenience, which typically have a lower degree of environmental records. The top five donor countries historically suffer from harmful algal bloom problems. The short journey and busy trading between these countries and Taiwan lead to a higher risk of inoculation. In addition, only 1.4% of all vessels visited more than once every year during the 9-year span, indicating that the port authority encounters many new vessels each year. These findings could influence the design and application of ballast water management strategies as well as highlight the challenges in their implementation. We suggest that an analysis of vessel traffic patterns should be coupled with other useful vessel information to make risk assessment successful.  相似文献   

17.
Ballast water is essential in maintaining the balance and structural integrity of ships during voyage. However, it has created biological invasion threats to the ocean environment. An innovative electrochemical technology was developed in this study. The microorganisms regulated by the International Maritime Organization (D2) were used as the target organisms. It was found that the required energy to meet the D2 was below 0.006 kWh/m3. The size of disinfector (m3) was about 0.5% of treatment flow rate (m3/h). The complete disappearance of chlorine in seawater was achieved after three days. The ballast tank corrosion was not worsened due to the application of technology. The ecotoxicity studies showed no toxic effect on fish, invertebrate, and algae. Finally, the environmental risk assessment showed the treated water did not pose threats to the environment. It can therefore be concluded that the technology provides a cost-effective and environmental friendly solution to ballast water management.  相似文献   

18.
Under certain circumstances vessels do not need to meet ballast water management requirements as stated in the International Convention for the Management and Control of Ballast Water and Sediments (BWM Convention). Besides exceptions to ensure e.g., (a) the safety of a ship, (b) discharge of ballast water for the purpose of avoiding or minimizing pollution incidents, (c) uptake and discharge on high seas of the same ballast water, the same location concept comes into play as ballast water discharges from a ship at the same location where it was taken up is also excepted from BWM requirements. The term same location was not defined in this instrument, hence it is exposed to different interpretations (e.g., a terminal, a port, a larger area where two or more ports may be located). As the BWM Convention is an instrument with biological meaning, the authors recommend a biologically meaningful definition of the same location in this contribution.  相似文献   

19.
《Marine pollution bulletin》2012,64(5-12):119-123
Ballast water is essential in maintaining the balance and structural integrity of ships during voyage. However, it has created biological invasion threats to the ocean environment. An innovative electrochemical technology was developed in this study. The microorganisms regulated by the International Maritime Organization (D2) were used as the target organisms. It was found that the required energy to meet the D2 was below 0.006 kWh/m3. The size of disinfector (m3) was about 0.5% of treatment flow rate (m3/h). The complete disappearance of chlorine in seawater was achieved after three days. The ballast tank corrosion was not worsened due to the application of technology. The ecotoxicity studies showed no toxic effect on fish, invertebrate, and algae. Finally, the environmental risk assessment showed the treated water did not pose threats to the environment. It can therefore be concluded that the technology provides a cost-effective and environmental friendly solution to ballast water management.  相似文献   

20.
Dinoflagellate cysts are well-recognized biological constituents of ships' ballast tanks. They are present in ballast water, sediments and residual water in drained tanks, and in biofilms formed on interior tank surfaces. Therefore, cysts have the potential to be released during ballast discharge. The International Maritime Organization's (IMO) Ballast Water Management Convention (promulgated February 2004) stipulates a performance standard (Annex, Regulation D2) requiring discharged ballast water contain <10 viable organisms between 10 and 50 microm per ml and <10 viable organisms 50 microm per m3. The proposed size limit has potential to exclude both the smallest toxic and the largest toxic and non-toxic dinoflagellate (and other microalgal) cysts from discharged ballast water. Despite the appropriateness of size cutoffs however, ballast water containing predominantly small cysts (<50 microm) could be deemed in compliance with the performance standard, even without treatment, while ballast water having the same concentration of larger cysts (>50 microm) could require a multiple-log reduction in abundance before its permissible discharge. Also of concern, it remains uncertain whether ballast-water treatment can remove sufficient organisms, including dinoflagellate cysts, to meet the performance standard.  相似文献   

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