Sleutelaspect zoöplankton : analysedocument voor de basismonitoring Wadden

Dit document is opgesteld conform het format voor de analysedocumenten basismonitoring. Het doel van het analysedocument is: Vaststellen of we datgene monitoren wat we nodig hebben om te kunnen beoordelen of we met het gevoerde beheer de overeengekomen beleidsdoelen bereiken. Adviseren over de monitoring die gewenst is, maar nog ontbreekt. Het analysedocument beschrijft waar de monitoring niet toereikend is voor het analyseren van de doelen

Unravelling the myth – The use of Decisions Support Systems in marine management

Over the past decade the development of Decision Support Systems (DSSs) for the management of seas and oceans has increased rapidly. These DSSs take many shapes and forms and their application in actual decision processes varies widely. In order to appreciate the multitude of DSSs a theoretical framework was developed to evaluate the appropriateness of a given DSS for marine management decision processes with the aim to guide developers in building better DSSs. This framework was applied to a number of DSSs recently developed for marine management. Many tools, promoted to be DSSs, are in fact science driven models that do not address the basic problems and challenges of decision making. Of course, by providing information and making scientific data available in order to make scientifically informed decisions, science does have a role in environmental and ecosystem based decision making, yet the contribution of science to decision making in marine management by these models is highly overrated. In order for a DSS to be relevant and useful it must be aligned with the needs of the decision maker and provide available data in such a way that it becomes information in the decision process. The framework used to evaluate the DSSs can be a helpful tool to apply throughout the development of a DSS in order to enhance the effectiveness/usefulness of these tools through the engagement of end-users and stakeholders

Comparison of Substance‐Based and Whole‐Effluent Toxicity of Produced Water Discharges from Norwegian Offshore Oil and Gas Installations

When assessing the environmental risks of offshore produced water discharges, it is key to properly assess the toxicity of this complex mixture. Toxicity can be assessed either through the application of whole-effluent toxicity (WET) testing or based on its substance-based chemical composition or both. In the present study, the toxicity assessed based on WET and substance-based was compared for 25 offshore produced water effluents collected for the Norwegian implementation of the Oslo–Paris convention risk-based assessment program. The objectives were, firstly, to examine the concurrence between toxicity estimates derived from these two lines of evidence; and, secondly, to evaluate whether toxicity of produced water discharges predicted from substance-based data is adequately addressed in comparison with ground truth reflected by WET. For both approaches, 50% hazardous concentrations (HC50s) were calculated. For at least 80% of the effluents the HC50s for the two approaches differed by less than a factor of 5. Differences found between the two approaches can be attributed to the uncertainty in the estimation of the concentration of production chemicals that strongly influences the substance-based estimated toxicity. By evaluating effluents on a case-by-case basis, additional causes were hypothesized. Risk management will particularly benefit from the strength of risk endpoints from both approaches by monitoring them periodically in conjunction over time. This way (in)consistencies in trends of both indicators can be evaluated and addressed

Voorstel voor monitoring van zoöplankton in de Noordzee : monitoringplan zoöplankton MONS ID14

In this report, a draft plan for monitoring and supporting research of zooplankton in the Dutch part of the North Sea has been drawn up. The aim is to draw up a zooplankton monitoring plan that can provide answers to the following questions in due course: What is the composition and distribution of zooplankton in space and time? And also: what are the trends (years and decades) (in composition and distribution of zooplankton in space and time) and what are the effects of new human use? The results from the monitoring should enable to understand and predict changes in zooplankton in the North Sea, so that validated scenario studies can be performed. All this in order to be able to assess the ecological capacity and the effects of individual and cumulative use thereon. The monitoring plan consists of two phases, a 1-year inventory study and a 4-year monitoring to test whether the results can be used to answer the questions. First of all, an overview was drawn up of the available knowledge about the policy frameworks and goals for zooplankton monitoring, an overview was given of monitoring activities in the Netherlands and other North Sea countries and a description was made of conventional and innovative techniques that are used for zooplankton monitoring. Internationally (e.g. OSPAR) the focus is currently mainly on indicators that indicate the role of zooplankton in the food chain. The density and size distribution of the mesozooplankton (0.2 – 20 mm) is used as an indicator for the food availability of fish. Biodiversity is also important. These indicators can be measured in different ways. In addition to classical methods, in which net samples are analyzed under the microscope, more and more innovative methods are being used. Phase 1: The plan for the first phase concerns a 1-year study aimed at determining the required resolution for identifying trends in space and time and the feasibility of innovative techniques to be used in the monitoring of zooplankton. The plan includes which classical and innovative techniques can be used and how these can contribute to answering the knowledge questions. This concerns the collection of zooplankton with net samples and the analysis thereof, such as by means of microscopy, image analysis or DNA metabarcoding, and the application of in situ techniques, such as dragging a video plankton recorder, acoustic measurements and the use of scanners. Three sailing trips have been proposed for this and measurements at fixed measuring stations. Phase 2: The plan for phase 2 is still surrounded by uncertainties, because it is being implemented on the basis of the findings of phase 1. In this project, only a preliminary plan can be drawn up for a 4- year program and budgeted on the basis of the number of measurement locations and times. These will be smaller compared to the monitoring of phase 1. It is also unclear at the start of phase 2 which techniques will ultimately be selected, so that a specification must also be made for this

Developing an Environmental Impact Assessment for Floating Island Applications

In the Space@Sea project a conceptual study is performed to develop standardized cost efficient floating modular islands with low environmental impact. As these floating modular islands are introduced for a purpose which is likely to determine the environmental impact, possible applications were considered: living, aquaculture, ports and logistics, and energy hub. The aim of this study is to develop a structured approach for Environmental Impact Assessments (EIAs) of floating modular islands and their applications as these are considered within the Space@Sea project. To contribute to the efficiency and sustainability of future floating island developments, early awareness of the likely environmental consequences is important and requires a solid knowledge base. To that end we recommend a screening approach to identify the main threats to the marine ecosystem and their potential impacts at the earliest (conceptual) stage of development. For each Space@Sea type of application, this screening approach should identify the main threats through an EIA that links critical pressures with sensitive ecosystem components. While conventional impact assessments only consider negative impacts, we also consider potential environmental benefits of floating islands. This not only to enhance more environmental-friendly designs but also to provide a balanced perspective which considers not only threats but also opportunities in future developments and implementation of floating islands and their applications.</p

Low genetic connectivity in a fouling amphipod among man-made structures in the southern North Sea

Offshore environments are increasingly invaded by man-made structures that form hard-substrate habitats for many marine species. Examples include oil and gas platforms, wind turbines and shipwrecks. One of the hypothesised effects is an increased genetic connectivity among natural populations due to new populations growing on man-made structures that may act as stepping stones. However, few data are available on genetic connectivity among organisms inhabiting artificial offshore structures. Here, we present a study on the common fouling amphipod Jassa herdmani from offshore structures in the southern North Sea. Partial mitochondrial DNA sequences (cytochrome-c-oxidase 1, N = 514) were obtained from artificial structures at 17 locations in the southern North Sea, including 13 shipwrecks, 2 wind turbines and 2 platforms. Samples from these locations were significantly differentiated, meaning that strong population structure exists for this species in the area. Levels of intraspecific variation were consistent with stable population sizes. No evidence was found for isolation by distance. Using coalescent simulations, the oldest population subdivision events were estimated to date back to the time the study area was flooded following the Last Glacial Maximum. We therefore tentatively conclude that J. herdmani may have colonised man-made structures from previously existing populations on the sea floor, and that the increase in offshore installations has not led to an overall increase in genetic connectivity for this species

Functional and structural impact of linuron on a freshwater community of primary producers: the use of immobilized algae

An approach in determining ecosystem integrity and stress on ecosystem level is to assess processes within ecosystems. The aim of the present study was to evaluate the potential use of an in situ assay with immobilized Chlorella vulgaris as an indicator of effects on ecosystem functioning with regard to primary production. The herbicide linuron, applied in concentrations of 20, 60, and 180 mu g linuron/L, was used to induce direct effects on primary producers. Direct and indirect changes in structure and function within outdoor model ecosystems of 3 m(3) were monitored. The intermediate and highest concentration of linuron caused a decline in growth of the macrophyte Elodea sp., resulting in a significant increase of concentrations of nutrients. The increase in concentrations of nutrients caused an indirectly stimulated growth of immobilized C. vulgaris at the intermediate concentration, whereas similar concentrations of nutrients, at the highest treatment, did not stimulate Chlorella growth. It appeared that the direct effect of linuron on C. vulgaris growth was masked by nutrient availability at the intermediate but not at the highest linuron concentration. The observed immobilized algal growth was an accumulated effect of toxic and trophic pressures within the ecosystem, resulting in an integrative endpoint to detect actual impairment of ecosystem function.TARGET - EVK1 1999–0000