ALBERT

Description: Kelp forests represent a major habitat type in coastal waters worldwide and their structure and distribution is predicted to change due to global warming. Despite their ecological and economical importance, there is still a lack of reliable spatial information on their abundance and distribution. In recent years, various hydroacoustic mapping techniques for sublittoral environments evolved. However, in turbid coastal waters, such as off the island of Helgoland (Germany, North Sea), the kelp vegetation is present in shallow water depths normally excluded from hydroacoustic surveys. In this study, single beam survey data consisting of the two seafloor parameters roughness and hardness were obtained with RoxAnn from water depth between 2 and 18 m. Our primary aim was to reliably detect the kelp forest habitat with different densities and distinguish it from other vegetated zones. Five habitat classes were identified using underwater-video and were applied for classification of acoustic signatures. Subsequently, spatial prediction maps were produced via two classification approaches: Linear discriminant analysis (LDA) and manual classification routine (MC). LDA was able to distinguish dense kelp forest from other habitats (i.e. mixed seaweed vegetation, sand, and barren bedrock), but no variances in kelp density. In contrast, MC also provided information on medium dense kelp distribution which is characterized by intermediate roughness and hardness values evoked by reduced kelp abundances. The prediction maps reach accordance levels of 62% (LDA) and 68% (MC). The presence of vegetation (kelp and mixed seaweed vegetation) was determined with higher prediction abilities of 75% (LDA) and 76% (MC). Since the different habitat classes reveal acoustic signatures that strongly overlap, the manual classification method was more appropriate for separating different kelp forest densities and low-lying vegetation. It became evident that the occurrence of kelp in this area is not simply linked to water depth. Moreover, this study shows that the two seafloor parameters collected with RoxAnn are suitable indicators for the discrimination of different densely vegetated seafloor habitats in shallow environments.

Description: The state and development of coastal marine systems and an understanding of the interaction of organisms, sea floor, water column, and biochemical and physical processes can only be obtained by a combination of long-term monitoring and modelling approaches of different complexity. A need for the development and evaluation of monitoring strategies is driven by a framework of different European and German regulations. The research project WIMO (Scientific Monitoring Concepts for the German Bight) has developed concepts and methods that aim at a fundamental scientific understanding of marine systems and also meet monitoring requirements of European legislation and regulations like the EU Marine Strategy Framework Directive. In this final report examples of common descriptors of ecosystem state like seabed integrity, eutrophication, and biodiversity are discussed. It has been assessed to what extent established measuring procedures used to survey the characteristics of the sea floor, and newly developed technologies are eligible for governmental monitoring. The significance of integrative modelling for linking and visualising results of measurements and models is illustrated. It is shown how new concepts have been implemented into governmental monitoring in the form of web based data sheets. These insights enable continuous analyses and developments in the future.

Description: Shore nourishments are regarded as an almost routine coastal protection measure and have been carried out worldwide for several decades. Recent studies generally conclude that “soft” coastal protection measures are an effective option for a sustainable coastal management. However, more research on economic sustainability, species-specific habitat demands and availability of sand deposits is required. Nowadays, the recent paradigm shifts to concepts like the Integrated Coastal Zone Management (ICZM) and the Ecosystem Approach to Management (EAM). For the German Wadden Sea these management objectives are an important issue of the “Wattenmeerstrategie 2100” , a political strategy report that demands an adaption against the global change and the expected sea-level rise up to the year 2100. Hence, also new concepts and tools for the implementation of more sustainable, effective and environment-friendly shore nourishments are needed. The research project STENCIL joins the expertise of coastal engineers, geologists, biologists and toxicologists in order to make a first step towards the long-term goal of establishing an ICZM and EAM for shore nourishments in the German Wadden Sea. The project focuses on providing improved tools, models and methods for the prediction of coastal hydro- and morphodynamics. Furthermore, the impact of dredging and dumping activities on benthic habitats and their natural regeneration potentials will be evaluated. Since these impacts are still widely uninvestigated, monitoring of dredging areas and the surrounding sites using hydroacoustic devices, aerial photos and sediment samples for grain-size and benthos analysis remains of high importance. In order to develop standardized operative observation methods, analysis and decision-supporting tools, an implementation of field measurements, laboratory experiments as well as conceptual and numerical models is planned. These combined approaches will result in valuable data sets for habitat evaluation, improved prediction methods as well as process and work-flow studies. Finally, a strategy for future planning and monitoring of shore nourishment projects will be established in close cooperation with the coastal authorities. STENCIL has recently started in October 2016 within the research program “Research for sustainable development” (FONA) of the German Federal Ministry of Education and Research (BMBF). The poster will give an overview of the project structure and present the research objectives and methods in more detail.

Description: Die SWOT-Analyse zeigt, dass jedes Verfahren für die Materialentnahme und die Aufspülung eine Reihe von Vor- und Nachteilen mit sich bringt, die der Anwender gegeneinander abwägen muss. Mit weiteren Forschungsergebnissen, v.a. hinsichtlich der langfristigen ökologischen und morphologischen Auswirkungen der Verfahren, könnten einige der potenziellen Chancen und Risiken zu bekannten und absehbaren Stärken bzw. Schwächen werden. Bis dahin muss der Anwender unter Berücksichtigung aller Faktoren ein Verfahren auswählen, das für den geplanten Anwendungsfall geeignet ist und bei dem die Risiken für die Region vertretbar sind. Dabei muss jedoch beachtet werden, dass viele bisher unbekannte biologische Prozesse möglicherweise weitere Auswirkungen auf das Küstenökosystem haben könnten. Daher sind Eingriffe in die Küstenumwelt immer mit gewissen Risiken für das Ökosystem und den Menschen verbunden und sollten nur dann erfolgen, wenn sie unter Abwägung der wesentlich beeinflussten marinen und terrestrischen Kompartimente und nach Diskussion und Priorisierung der primären Schutzziele (Lebens-, Natur- und Wirtschaftsraum) unbedingt erforderlich sind.

Description: Shore nourishments have been carried out worldwide for several decades and are nowadays seen as an almost routine coastal protection measure. However, the recent paradigm shift to an Integrated Coastal Zone Management (ICZM) and to an Ecosystem Approach to Management (EAM) requires new concepts, models and tools for the implementation of more sustainable and environmentally friendly shore nourishments. The interdisciplinary research project STENCIL aimed at making a first step towards the long-term goal of es- tablishing an EAM for shore nourishments. Joining the expertise of coastal engineers, ge- ologists and ecologists, the project has provided improved tools and methods for the pre- diction of coastal hydro- and morphodynamics and related ecological impacts. A combination of field measurements, laboratory experiments and analytical as well as nu- merical models has resulted in valuable new data sets. This paper summarizes the most important scientific outcomes of the project, like the use of Artificial Neural Networks (ANN) to overcome weaknesses of current hydrodynamic numerical modelling tools; the analysis and interpretation of long-term beach profile data using a newly developed data- driven methodology, allowing for a better assessment of the morphological development of beach and foreshore nourishments; the improvement of a sediment transport model for mixed sand based on a unique large-scale experiment in the Large Wave Flume (GWK) carried out within the project; an impact assessment of dredging activities around Sylt, based on six extensive survey cruises at the sand extraction sites “Westerland II & III”; and the application of the hydrotoxicology method for the same study site to determine the influence of sand extraction on chemical-physical water quality parameters and the ecotox- icological potential. These interdisciplinary project results were combined with a compre- hensive state of the art review in a SWOT analysis for shore nourishments, which shall provide a tool for decision-makers and a basis for upcoming research projects addressing the identified knowledge gaps.