Jennifer Dannheim

Semi-automated image analysis for the assessment of megafaunal densities at the Arctic deep-sea observatory HAUSGARTEN

Megafauna play an important role in benthic ecosystem function and are sensitive indicators of environmental change. Non-invasive monitoring of benthic communities can be accomplished by seafloor imaging. However, manual quantification of megafauna in images is labor-intensive and therefore, this organism size class is often neglected in ecosystem studies. Automated image analysis has been proposed as a possible approach to such analysis, but the heterogeneity of megafaunal communities poses a non-trivial challenge for such automated techniques. Here, the potential of a generalized object detection architecture, referred to as iSIS (intelligent Screening of underwater Image Sequences), for the quantification of a heterogenous group of megafauna taxa is investigated. The iSIS system is tuned for a particular image sequence (i.e. a transect) using a small subset of the images, in which megafauna taxa positions were previously marked by an expert. To investigate the potential of iSIS and compare its results with those obtained from human experts, a group of eight different taxa from one camera transect of seafloor images taken at the Arctic deep-sea observatory HAUSGARTEN is used. The results show that inter- and intra-observer agreements of human experts exhibit considerable variation between the species, with a similar degree of variation apparent in the automatically derived results obtained by iSIS. Whilst some taxa (e. g. Bathycrinus stalks, Kolga hyalina, small white sea anemone) were well detected by iSIS (i. e. overall Sensitivity: 87%, overall Positive Predictive Value: 67%), some taxa such as the small sea cucumber Elpidia heckeri remain challenging, for both human observers and iSIS.

Offshore wind park monitoring programmes, lessons learned and recommendations for the future.

Over a decade of monitoring offshore wind park environmental impact triggered a reflection on the overall objectives and how to best continue with the monitoring programmes. Essentially, basic monitoring has to be rationalised at the level of the likelihood of impact detection, the meaningfulness of impact size and representativeness of the findings. Targeted monitoring is crucial and should continue to be applied to disentangle processes behind observed impacts, for instance the overarching artificial reef effect caused by wind parks. The major challenge, however, remains to achieve a reliable assessment of the cumulative impacts. A continuous international consultation and collaboration with marine scientists, managers, government officials and industry will be needed to ensure an optimisation of the future monitoring programmes.

Rapid increase of benthic structural and functional diversity at the alpha ventus offshore test site

The ecological importance of benthic organisms, which provide valuable ecosystem goods and services, necessitates careful research into the effects of offshore windfarms on the marine benthos. This chapter summarizes the results from benthos research activities within the StUKplus programme. The results showed considerable effects of the windfarm alpha ventus on the abundance and biomass of the benthic fauna. The major effect of the introduction of numerous wind turbine constructions into the marine environment was the aggregation and production of marine biota on the submersed structures, resulting in a substantial increase of the structural and functional biodiversity of the benthic system.

Functional Diversity and Traits Assembly Patterns of Benthic Macrofaunal Communities in the Southern North Sea

The study of ecosystem functioning—the fluxes of energy and material through biotic and abiotic components of an ecosystem—is becoming increasingly important in benthic ecological research. We investigated the functional structure of macrozoobenthic communities at four long-term sampling sites in the southern North Sea using biological traits assigned to life history, morphological and behavioural characteristics. The “typical” species of the macrofaunal assemblages at the sampling sites was characterized by small to medium body size, infaunal burrowing life style, deposit feeding habit, omnivory diet type, short to medium life span, gonochoristic sexual differentiation, 330 macrofaunal taxa have been compiled in a comprehensive database.

Preface: the WinMon.BE 2013 conference: steps towards an efficient and effective offshore wind farm environmental impact assessment

The race for a timely combat of climate change through the reduction of greenhouse gasses such as carbon dioxide has pushed renewable energy developments to a higher echelon. At present, wind is one of the most profitable sources of exploitable renewable energy. Wind farms are popping up at many places worldwide. Their expansion on land, however is constrained, because sites where wind farms do not conflict with the high-quality environmental standards of the local community are limited. Being uninhabited, the marine environment offers a vast area for wind farm development. Being uninhabited, however, does not equal not being subject to impact. The sea and oceans host rich ecosystems, many of which have and continue to deliver priceless and indispensable goods and services to mankind. Offshore wind farm development is hence subject to environmental impact assessment and residual impacts should be carefully monitored. Most, if not all, current offshore wind farms are accompanied by an environmental monitoring programme. These programmes should be considered the ‘finger on the pulse’ to avoid surpassing critical impact levels. They further ensure the achievement of the knowledge base needed to adjust new developments in a scientifically and environmentally sensitive and sound manner. On 26–28 November 2013, the Royal Belgian Institute of Natural Sciences organised the international scientific WinMon.BE 2013 conference on ‘‘Environmental impacts of offshorewind farms: learning from the past to optimise future monitoring programmes’’ (http:// odnature.naturalsciences.be/winmonbe2013).During the Guest editors: Steven Degraer, Jennifer Dannheim, Andrew B. Gill, Han Lindeboom & Dan Wilhelmsson / Environmental impacts of offshore wind farms

Distribution and trajectories of floating and benthic marine macrolitter in the south-eastern North Sea

In coastal waters the identification of sources, trajectories and deposition sites of marine litter is often hampered by the complex oceanography of shallow shelf seas. We conducted a multi-annual survey on litter at the sea surface and on the seafloor in the south-eastern North Sea. Bottom trawling was identified as a major source of marine litter. Oceanographic modelling revealed that the distribution of floating litter in the North Sea is largely determined by the site of origin of floating objects whereas the trajectories are strongly influenced by wind drag. Methods adopted from species distribution modelling indicated that resuspension of benthic litter and near-bottom transport processes strongly influence the distribution of litter on the seafloor. Major sink regions for floating marine litter were identified at the west coast of Denmark and in the Skagerrak. Our results may support the development of strategies to reduce the pollution of the North Sea.

Multiscale spatial distribution of macrofauna response to fishery pressure

Trawling is one of the most damaging activities for fauna living at the ocean resulting in simultaneous pulse and chronic impacts on benthic communities on multiple spatio-temporal scales. Recently, high quality Vessel Monitoring by Satellite (VMS) data provides spatio-temporal information of swept area by fishery trawlers. Using this huge amount of information in combination with about 20 environmental descriptors, we aim to tease apart the effect of species endogenous features (i.e. dispersal capability) and exogenous factors (i.e. environmental conditions) on the fauna responses to fishery and its related spatial scales. We analyse data of 300 grab-samples taken in the German Bight (North Sea), encompassing 140 macrobenthic species collected on a regular grid over an area of about 8000 km2. We use Moran Eigenvector Maps to model patterns of potential connectivity between locations and shed light on which spatial scales fisheries, environmental characteristics, and macrobenthos are linked. Finally, we show maps of fauna response to fishery. We argue that despite the importance of proper quantification of fishing pressure and other human activities, shedding light on the effects and response to such activities is crucial for a sound understanding of the processes that shape ecosystems and diversity distribution.

Climate variability effects on long-term macrofaunal abundance trends in the German Bight (North Sea)

M shoreline prediction models assume uniform coastal material behavior along transect lines hence no provision is made for variability in the material properties. Such models produce reliable results where the coastal material is soft such as along sandy beaches. On the contrary, for a geological and geomorphological variable coastline like the western region of Ghana, the application of such existing models may yield erroneous predictions. This study identified the causes of shoreline change in the study area modeled it in terms of the driving and resistive factors influencing coastal erosion using a process based approach. Multi-temporal spatial datasets, hydrodynamic datasets and field measurements were used. The field data measured included: shear strength of coastal soil, compressive strength of coastal rocks, beach profiling and exposed beach width at systematically sampled locations within the study area. Other variables included are sediment supplied by fluvial, potential sediment transported alongshore and the exposed beach slope. Applying multiple regression model to the data, revealed that the exposed beach slope presumed to mimic the sea floor contributed significantly to shoreline change rates within the entire study area; this was followed by the strength of the coastal rock outcrops. It was realized that sea level rise is not a key candidate causing shoreline change in most parts of the study area. This present study shows that in designing shoreline prediction models for heterogeneous coastal materials it is recommended that beach slope and the strength of the coastal rock outcrops be included in the predictor variables.Three fish species were collected from Jizan area, Southern Red Sea, Saudi Arabia. These were Safi, Beda and Parrot. They were subjected to study the presence of chlorinated hydrocarbons in liver, muscle, gill, gut and kidney tissues of these species. Chlorinated pesticides and PCBs were examined y GC and GC-MS and quantification was achieved. The results showed the presence of these chemicals in studied species indicating minimum of 0.6 ng g dry wt to a maximum of 436 ng g dry wt. The highest level of chlorinated hydrocarbons was found in liver followed by kidney and gut tissues, while the lowest was found in muscle and gill tissues. The results revealed a certain degree of pollution which can be a risk to human and marine organisms. It is necessary to point out that this is the first attempt to measure the levels of chlorinated hydrocarbons in Red Sea fishes, therefore similar studies in Red Sea environment should be carried out in the near future in order to confirm the present results and to identify the sources of such contamination.R studies showed even isogenic populations of exponentially growing microorganisms carrying substantial cell-to-cell heterogeneities at both cellular and molecular levels that are an order of magnitude greater than previously thought. It is increasingly recognized that by using averaged molecular or phenotypic measurements of a whole population for describing cell behaviors, conclusions could be biased as the unique patterns related to specific or distinct functional sub-populations cannot be revealed. Recent progress in developing single-cell based technologies for gene expression analysis in single cells, including the first bacterial single-cell RNA-seq method for the whole transcriptome of single cyanobacterium cells which contain 5~7 femtogram total RNA per cell will be reported. The results provided evidences for significant gene-expression heterogeneity between single cells, and that the heterogeneity seems affected by the environmental stress conditions.T have been known for their ubiquitous distribution in the ocean. Results of several studies indicated that their abundance can exceed that of bacterioplankton in the oceanic waters. This talk will focus on the results of our recent studies on the diversity and abundance of thraustochytrids in the Pacific Ocean and the coastal waters of China. Our results indicate that the abundance of thraustochytrids indeed exceed that of bacterioplankton, but with low diversity, during fall season in both of oceanic and coastal waters. Their abundance was related to the maximuprimary production. However, they behave differently in their abundance and spatial distribution in the oceanic and coastal waters. Thraustochytrids may play a significant role in the ocean carbon cycling. The true diversity of thraustochytrids remains to be discovered.

Fuzzy coding of biological traits of macrobenthic species in the North Sea

Biological traits analysis is one of the most auspicious approaches to study the ecological functioning in marine ecosystems and provides a mechanistic link to ecosystem processes and properties. We used a Biological trait analysis to examine a dataset of 334 macrofaunal species that were collected at 4 long-term stations in the North Sea between 1969-2011. This data include seventeen biological traits related to life history (e.g. reproductive type) and behavior (e.g. feeding habit) of macrofuna species. In order to include all possible attributes of species, these traits were broken down into seventy-two categories. The affinities of the species to the categories were fuzzy coded with a scoring range of 0 to 3 (0= no affinity, 1= low affinity, 2=moderate affinity and 3=high association of taxon with the trait category). Missing values were supplemented by using information from the species in the nearest taxonomic level. If the affinity of a species to a category was not identified and there was no information available for the evaluation, a score of 0 was given for all the modalities associated with that species.