The spread of non-native species has been a subject of increasing concern since the 1980s when human-mediated transportation, mainly related to ships' ballast water, was recognized as a major vector ...for species transportation and spread, although records of non-native species go back as far as 16th Century. Ever increasing world trade and the resulting rise in shipping have highlighted the issue, demanding a response from the international community to the threat of non-native marine species. In the present study, we searched for available literature and databases on shipping and invasive species in the North-eastern (NE) and South-western (SW) Atlantic Ocean and assess the risk represented by the shipping trade between these two regions. There are reports of 44 species associated with high impacts for the NE Atlantic and 15 for the SW Atlantic, although this may be an underestimate. Vectors most cited are ballast water and biofouling for both regions while aquaculture has also been a very significant pathway of introduction and spread of invasive species in the NE Atlantic. Although the two regions have significant shipping traffic, no exchange of invasive species could be directly associated to the shipping between the two regions. However, it seems prudent to bring the exchange of ballast water between the two regions under control as soon as possible.
•44 invasive species recorded for the NE Atlantic and 15 for the SW Atlantic.•Most cited vectors are ballast water and biofouling for both regions.•Aquaculture is a very significant pathway of invasive species in the NE Atlantic.•No exchange of species was directly associated with the shipping in the study area.
Biofouling is a major vector in the transfer of non-native species around the world. Species can be transported on virtually all submerged areas of ships (e.g. hulls, sea chests, propellers) and so ...antifouling systems are used to reduce fouling. However, with increased regulation of biocides used in antifoulants (e.g. the International Maritime Organization tributyltin ban in 2008), there is a need to find efficient and sustainable alternatives. Here, we tested the hypothesis that short doses of low salinity water could be used to kill fouling species in sea chests. Settlement panels were suspended at 1.5 m depth in a Plymouth marina for 24 months by which time they had developed mature biofouling assemblages. We exposed these panels to three different salinities (7, 20 and 33) for 2 hours using a model sea chest placed in the marina and flushed with freshwater. Fouling organism diversity and abundance were assessed before panels were treated, immediately after treatment, and then 1 week and 1 month later. Some native ascidian Dendrodoa grossularia survived, but all other macrobenthos were killed by the salinity 7 treatment after 1 week. The salinity 20 treatment was not effective at killing the majority of fouling organisms. On the basis of these results, we propose that sea chests be flushed with freshwater for at least 2 hours before ships leave port. This would not cause unnecessary delays or costs and could be a major step forward in improving biosecurity.
Ten years of Brazilian ballast water management Castro, Maria Cecilia Trindade; Hall-Spencer, Jason M.; Poggian, Cecília Fonseca ...
Journal of sea research,
March 2018, 2018-03-00, 20180301, Letnik:
133
Journal Article
Recenzirano
Odprti dostop
In 2005, Brazil addressed the environmental challenges posed by ballast water through a unilateral regulation, called the Maritime Standard N° 20 (NORMAM-20), applied to all shipping in her waters. ...This world-leading decision was the culmination of a process that started during the 1990′s. Here, we summarize how these ballast water regulations were brought in and adopted and present the findings of 10years of enforcement (2005–2015) in 39 ports along the Brazilian coast. We show that compliance with the Brazilian standard has increased significantly since the regulations were implemented (p<0.001). After five years of implementation, non-compliance decreased probably reflecting an increase in awareness of the Brazilian Standard and a shift in the shipping industry commitment to minimize and control the spread of invasive species through ballast water. The Brazilian experience shows that very high levels (97%) of compliance with ballast water management regulations can be made to work in a region of global importance to the maritime industry. In the last decade, the rules governing ballast water in Brazil have evolved to address the demands from the maritime community and to provide updates such as imminent requirements for the use of ballast water management systems on board ships. These regulations are rarely cited when ballast water regulations are discussed internationally, yet there is much to learn from the proactive approach taken by Brazil such as what is feasible and enforceable.
•10years of ballast water enforcement in 39 ports in Brazil are presented;•Ships' compliance increased significantly since the Standard was adopted (p<0.001);•Results showed high levels of compliance (97%) with ballast water regulations;•A uniform procedure of sampling and analysis is currently being developed.
Shipping is recognised as an unintentional efficient pathway for spreading non-native species, harmful organisms and pathogens. In 2004, a unique IMO Convention was adopted to control and minimize ...this transfer in ship's ballast water. This Convention entered into force on 8th September 2017. However, unlikely the majority of IMO Conventions, the Ballast Water Management Convention requires ships to comply with biological standards (e.g. concentration of organisms per unit of volume in ballast water discharges). This study aimed to apply different techniques developed to measure concentrations of viable phytoplankton in natural and treated ballast water samples and compare them with the established flow cytometry method and vital staining microscopy. Samples were collected in the English Channel over one year and on-board during ballast water shipboard efficacy tests. Natural abundance of live phytoplankton varied from 23% to 89% of the total, while for cells larger than 10 μm (a size defined by the BWM Convention) the percentage varied from 3% to 60%. An overall good correlation was seen between the measurements taken with the two fluorometers and in comparison with the flow cytometry analysis, as found in previous studies. Analysis of treated ballast water samples showed a large variation in the number of viable cells, however indicating a low level of risk on all occasions for regulatory purposes. One of the key aspects to bear in mind when sampling and analysing for compliance is to be aware of the limitations of each technique.
•Different techniques have been proposed for measuring viable cells in ballast water.•Good correlation was seen between the measurements taken with the two fluorometers.•Treated ballast water analysis showed a large variation in the number of viable cells.•It is important to be aware of each technique's limitations for CME purposes.
The vertical distributions of
21OPb,
210Po and
234Th in both dissolved and particulate phases of seawater were measured at five stations along the 85°W meridian in the Bellingshausen Sea, Antarctica. ...Sea-ice conditions during the expedition ranged from fully ice-covered (fast ice) to open water away from the marginal ice zone. Concurrent primary productivity and algal chlorophyll measurements revealed a band of high productivity at approximately 67°30′S, which remained in a rather static location during ice melt-back. Along the transect a progressive increase in removal (“scavenging”) and sinking of
210Pb,
210Po and
234Th occurred towards the north (open water conditions). Application of a simple, irreversible scavenging model, and particulate organic carbon and organic nitrogen to radionuclide ratios measured on suspended particulate matter, allows the calculation of export production for this region. Under fast ice conditions some removal of phytodetritus from the euphotic zone was observed (1–2 mgC m
−2 day
−1), representing a low proportion of the primary production (
f-ratio of 0.02). Near the Antarctic continental margin upwelling of regenerated dissolved
210Po was found. At the open water site near the algal band, new production had risen to 27–252 mgC m
−2 day
−1, but a greater proportion of the original primary production was removed by sinking detritus (
f-ratio of 0.03–0.33). Comparison of
210Po and
234Th as tracers of of export production indicates considerable differences, with
210Po yielding rather lower rates of export flux compared to
234Th Radionuclide estimates of new production are significantly greater than those obtained by traditional sediment trap methods. This may be due to the dynamic nature (short duration and spatial variability) of algal growth in the Southern Ocean.
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