China-Algen in der Ostsee

Verklebte Fischerei-Netze, gestörte Organismen, schwere gesundheitliche Schäden, eingehandelt im "ach so sauberen Seewasser", sind die Folgen einer unsichtbaren Invasion. In den letzten 150 Jahren haben sich alleine in Nord- und Ostsee mehr als 100 neue Arten angesiedelt, die aus fernen Regionen stammen. Nichtheimische Arten neigen zur Massenvermehrung und richten millionenschweren Schaden an. Aus dem Chinesischen Meer stammende Algen bevölkern inzwischen unsere Randmeere, die Sandklaffmuschel - ursprünglich an der nordamerikanischen Ostküste beheimatet - tummelt sich im Wattenmeer, der Schiffsbohrwurm wurde im Ballastwasser herangefahren. Mangels Masse begnügt er sich mit dem Verzehr hölzerner Hafenanlagen. Aus China stammt die schädliche Wollhandkrabbe. Eingeschleppt wurde auch die Pantoffelschnecke

Open-access journal Aquatic Invasions: an important part of the developing European information and early warning system on invasive alien species

Aquatic Invasions is considered as an example of an effective information sharing tool, currently helping to increase prompt reporting of records of new invasive species threatening European biodiversity

Zur Gefährdung unserer Küstengewässer durch über Ballastwasser und Schiffsbewuchs eingeschleppte Organismen: erste Untersuchungsergebnisse

Damit ein Schiff unabhängig vom Beladungszustand stabil im Wasser liegt, muß ein Gewichtsausgleich durch Ballastwasser geschaffen werden. Dieses Wasser wird in den Häfen beim Be- und Entladen des Schiffes aufgenommen oder abgepumpt. Zusammen mit dem Ballastwasser können auch Pflanzen und Tiere (z.B. Algen, Kleinkrebse und Fische) mit aufgenommen werden, und so auf dem Seewege als „blinde Passagiere" weite Strecken zurücklegen. Findet ein eingeschleppter Organismus am Ziel seiner Reise günstige Bedingungen vor, so kann er sich dort massenhaft ausbreiten, und so zum ökologischen und ökonomischen Schädling werden. Ein Forschungsvorhaben von Umweltbundesamt, dem Institut für Meereskunde, Kiel, und der Universität Hamburg, soll nun klären, ob mit dem Schiffsverkehr eingeschleppte Organismen eine Gefahr für deutsche Gewässer darstellen

Survival of tropical ballast water organisms during a cruise from the Indian Ocean to the North Sea

In an assessment of non-indigenous species transported by international ship traffic to German waters, commissioned by the German Federal Environmental Agency, the survival of tropical plankton organisms in ballast water was studied by accompanying a container vessel on its 23-day voyage from Singapore to Bremerhaven in Germany. Two tanks, one filled off Singapore and the other off Colombo, Sri Lanka, were monitored for their phyto- and zooplankton content by daily sampling. As already reported in previous studies, species abundance and diversity, especially of zooplankton, decreased sharply during the first days, and only a few specimens survived the whole cruise. The contents of the Colombo tank, however, changed dramatically during the last week. The harpacticoid copepod, Tisbe graciloides, increased its abundance by a factor of 100 from 0.1 to 10ind. l–1 within a few days. This is the first time that a ballast water organism has been found to multiply at such a high rate. Opportunistic species such as Tisbe are apparently able to thrive and propagate in ballast water tanks under certain conditions. Ballast water tanks may thus serve as incubators for certain species depending on their characteristics

Einschleppung fremder Arten in Nord- und Ostsee: Untersuchungen zum ökologischen Gefahrenpotential durch den Schiffsverkehr

Umweltforschungsplan des Bundesministers für Umwelt, Naturschutz und Reaktorsicherheit: Wasser: Forschungsbericht 102 04 25

Combining ballast water exchange and treatment to maximize prevention of species introductions to freshwater ecosystems

The most effective way to manage species transfers is to prevent their introduction via vector regulation. Soon, international ships will be required to meet numeric ballast discharge standards using ballast water treatment (BWT) systems, and ballast water exchange (BWE), currently required by several countries, will be phased out. However, there are concerns that BWT systems may not function reliably in fresh and/or turbid water. A land-based evaluation of simulated ‘BWE plus BWT’ versus ‘BWT alone’ demonstrated potential benefits of combining BWE with BWT for protection of freshwater ecosystems. We conducted ship-based testing to compare the efficacy of ‘BWE plus BWT’ versus ‘BWT alone’ on voyages starting with freshwater ballast. We tested the hypotheses that there is an additional effect of ‘BWE plus BWT’ compared to ‘BWT alone’ on the reduction of plankton, and that taxa remaining after ‘BWE plus BWT’ will be marine (low risk for establishment at freshwater recipient ports). Our study found that BWE has significant additional effect on the reduction of plankton, and this effect increases with initial abundance. As per expectations, ‘BWT alone’ tanks contained higher risk freshwater or euryhaline taxa at discharge, while ‘BWE plus BWT’ tanks contained mostly lower risk marine taxa unlikely to survive in recipient freshwater ecosystems

Simulating the spread of disinfection by-products and anthropogenic bromoform emissions from ballast water discharge in Southeast Asia

Ballast water treatment is required for vessels to prevent the introduction of potentially invasive neobiota. Some treatment methods use chemical disinfectants which produce a variety of halogenated compounds as disinfection by-products (DBPs). One of the most abundant DBP from oxidative ballast water treatment is bromoform (CHBr3) where we find an average concentration of 894±560nmolL-1 (226±142μgL-1) in the undiluted ballast water from measurements and literature. Bromoform is a relevant gas for atmospheric chemistry and ozone depletion, especially in the tropics where entrainment into the stratosphere is possible. The spread of DBPs in the tropics over months to years is assessed here for the first time. With Lagrangian trajectories based on the NEMO-ORCA12 model velocity field, we simulate DBP spread in the sea surface and try to quantify the oceanic bromoform concentration and emission to the atmosphere from ballast water discharge at major harbours in the tropical region of Southeast Asia. The exemplary simulations of two important regions, Singapore and the Pearl River Delta, reveal major transport pathways of the DBPs and the anthropogenic bromoform concentrations in the sea surface. Based on our simulations, we expect DBPs to spread into the open ocean, along the coast and also an advection with monsoon-driven currents into the North Pacific and Indian Ocean. Furthermore, anthropogenic bromoform concentrations and emissions are predicted to increase locally around large harbours. In the sea surface around Singapore we estimate an increase in bromoform concentration by 9% compared to recent measurement. In a moderate scenario where 70% of the ballast water is chemically treated bromoform emissions to the atmosphere can locally exceed 1000pmolm-2h-1 and double climatological emissions. In the Pearl River Delta all bromoform is directly outgassed which leads to an additional bromine (Br) input into the atmosphere of 495kmolBr (∼42tCHBr3) a-1. From Singapore ports the additional atmospheric Br input is calculated as 312kmolBr (∼26tCHBr3) a-1. We estimate the global anthropogenic Br input from ballast water into the atmosphere of up to 13Mmola-1. This is 0.1% global Br input from background bromoform emissions and thus probably not relevant for stratospheric ozone depletion

'Double trouble': the expansion of the Suez Canal and marine bioinvasions in the Mediterranean Sea

4 páginasPeer reviewe

Emerging risks from ballast water treatment: The run-up to the International Ballast Water Management Convention

AbstractUptake and discharge of ballast water by ocean-going ships contribute to the worldwide spread of aquatic invasive species, with negative impacts on the environment, economies, and public health. The International Ballast Water Management Convention aims at a global answer. The agreed standards for ballast water discharge will require ballast water treatment. Systems based on various physical and/or chemical methods were developed for on-board installation and approved by the International Maritime Organization. Most common are combinations of high-performance filters with oxidizing chemicals or UV radiation. A well-known problem of oxidative water treatment is the formation of disinfection by-products, many of which show genotoxicity, carcinogenicity, or other long-term toxicity. In natural biota, genetic damages can affect reproductive success and ultimately impact biodiversity. The future exposure towards chemicals from ballast water treatment can only be estimated, based on land-based testing of treatment systems, mathematical models, and exposure scenarios. Systematic studies on the chemistry of oxidants in seawater are lacking, as are data about the background levels of disinfection by-products in the oceans and strategies for monitoring future developments. The international approval procedure of ballast water treatment systems compares the estimated exposure levels of individual substances with their experimental toxicity. While well established in many substance regulations, this approach is also criticised for its simplification, which may disregard critical aspects such as multiple exposures and long-term sub-lethal effects. Moreover, a truly holistic sustainability assessment would need to take into account factors beyond chemical hazards, e.g. energy consumption, air pollution or waste generation