State Agency for Agriculture

Flintbek, Germany

State Agency for Agriculture

Flintbek, Germany
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Jorgensen F.,Geological Survey of Denmark | Scheer W.,State Agency for Agriculture | Thomsen S.,Danish Nature Agency Ribe | Sonnenborg T.O.,Geological Survey of Denmark | And 7 more authors.
Hydrology and Earth System Sciences | Year: 2012

Geophysical techniques are increasingly being used as tools for characterising the subsurface, and they are generally required to develop subsurface models that properly delineate the distribution of aquifers and aquitards, salt/freshwater interfaces, and geological structures that affect groundwater flow. In a study area covering 730 km2 across the border between Germany and Denmark, a combination of an airborne electromagnetic survey (performed with the SkyTEM system), a high-resolution seismic survey and borehole logging has been used in an integrated mapping of important geological, physical and chemical features of the subsurface. The spacing between flight lines is 200-250 m which gives a total of about 3200 line km. About 38 km of seismic lines have been collected. Faults bordering a graben structure, buried tunnel valleys, glaciotectonic thrust complexes, marine clay units, and sand aquifers are all examples of geological structures mapped by the geophysical data that control groundwater flow and to some extent hydrochemistry. Additionally, the data provide an excellent picture of the salinity distribution in the area and thus provide important information on the salt/freshwater boundary and the chemical status of groundwater. Although the westernmost part of the study area along the North Sea coast is saturated with saline water and the TEM data therefore are strongly influenced by the increased electrical conductivity there, buried valleys and other geological elements are still revealed. The mapped salinity distribution indicates preferential flow paths through and along specific geological structures within the area. The effects of a future sea level rise on the groundwater system and groundwater chemistry are discussed with special emphasis on the importance of knowing the existence, distribution and geometry of the mapped geological elements, and their control on the groundwater salinity distribution is assessed. © Author(s) 2012.


Martin P.,University of Kiel | Brunke M.,State Agency for Agriculture
Freshwater Science | Year: 2012

Creation of spring typologies for different regions is essential for evaluating spring degradation and for restoration of headwaters. We present a regional spring typology for the German federal state Schleswig-Holstein in the Northern European Lowlands. We used a standardized physicochemical and hydromorphological protocol to map 174 near-natural springs distributed area-wide. Principal component analysis distinguished types of springs (rheocrenes, helocrenes, limnocrenes, and an intermediate type, rheohelocrenes) on the basis of water chemistry and substratum composition. The spatial distribution of the types corresponded with the regional fluvioglacial landscapes of Schleswig-Holstein (hill country, Baltic Sea margin, the high Geest, and the low Geest). The most important discriminating factors were related to water hardness and conductivity. We sampled macroinvertebrates in 60 springs (twice in 40, once in 20) selected based on type and distribution among fluvioglacial landscapes. We detected 121 taxa, most of them Hydrachnidia (25 species), Trichoptera (19), Coleoptera (19), and Gastropoda (12). Many of the species are considered rare for Schleswig-Holstein (regional red-list species). Forty-two species were restricted mainly to springs (crenobiont or crenophilous species). Average taxon richness was similar for helocrenes (23 species), rheohelocrenes (22), and rheocrenes (25), but markedly lower for limnocrenes (11). Species composition differed between rheocrenes and helocrenes and between limnocrenes and all other spring types. Faunal distinctness of rheohelocrenes was less pronounced. We were able to produce a validated spring typology founded on substratum composition, physicochemical factors, and taxon composition. This typology can serve as a guide for restoration of severely degraded springs and headwaters in Schleswig-Holstein and in similar areas of Central Europe. © 2012 The Society for Freshwater Science.


Schubert P.R.,Leibniz Institute of Marine Science | Hukriede W.,Leibniz Institute of Marine Science | Karez R.,State Agency for Agriculture | Reusch T.B.H.,Leibniz Institute of Marine Science
Marine Ecology Progress Series | Year: 2015

In the northern hemisphere, eelgrass Zostera marina L. is the most important and widespread seagrass species. Despite its ecological importance, baseline data on eelgrass distribution and abundance are mostly absent, particularly in subtidal areas with relatively turbid waters. Here, we report a combined approach of vegetation mapping in the Baltic Sea coupled to a species distribution model (SDM). Eelgrass cover was mapped continuously in the summers of 2010 and 2011 with an underwater towed camera along ∼400 km of seafloor. Eelgrass populated 80% of the study region and occurred at water depths between 0.6 and 7.6 m at sheltered to moderately exposed coasts. Mean patch length was 128.6 m but was higher at sheltered locations, with a maximum of >2000 m. The video observations (n = 7824) were used as empiric input to the SDMs. Using generalized additive models, 3 predictor variables (depth, wave exposure, and slope), which were selected based on Akaike's information criterion, were sufficient to predict eelgrass presence/ absence. Along with a very good overall discriminative ability (area under the receiver-operating characteristic curve ROC/AUC = 0.82), depth (as a proxy for light), wave exposure, and slope contributed 66, 29, and 5%, respectively, to the final model. The estimated total areal extent of eelgrass in the study region amounts to 140.5 km2 and comprises about 11.5% of all known Baltic seagrass beds. The present work is, to the best of our knowledge, the largest study undertaken to date on vegetation mapping and the first to assess distribution of eelgrass quantitatively in the western Baltic Sea. © Inter-Research 2015.


Munkes B.,Leibniz Institute of Marine Science | Schubert P.R.,Leibniz Institute of Marine Science | Karez R.,State Agency for Agriculture | Reusch T.B.H.,Leibniz Institute of Marine Science
Marine Pollution Bulletin | Year: 2015

Seagrass meadows, one of the world's most important and productive coastal habitats, are threatened by a range of anthropogenic actions. Burial of seagrass plants due to coastal activities is one important anthropogenic pressure leading to the decline of local populations. In our study, we assessed the response of eelgrass Zostera marina to sediment burial from physiological, morphological, and population parameters. In a full factorial field experiment, burial level (5-20. cm) and burial duration (4-16. weeks) were manipulated. Negative effects were visible even at the lowest burial level (5. cm) and shortest duration (4. weeks), with increasing effects over time and burial level. Buried seagrasses showed higher shoot mortality, delayed growth and flowering and lower carbohydrate storage. The observed effects will likely have an impact on next year's survival of buried plants. Our results have implications for the management of this important coastal plant. © 2015 Elsevier Ltd.


Heinrich C.,State Agency for Agriculture | Heinrich C.,University of Kiel | Feldens P.,Leibniz Institute for Baltic Sea Research | Schwarzer K.,University of Kiel
Geo-Marine Letters | Year: 2016

Hydroacoustic surveys are common tools for habitat investigation and monitoring that aid in the realisation of the aims of the EU Marine Directives. However, the creation of habitat maps is difficult, especially when benthic organisms densely populate the seafloor. This study assesses the sensitivity of entropy and homogeneity image texture parameters derived from backscatter strength data to benthic habitats dominated by the tubeworm Lanice conchilega. Side scan sonar backscatter surveys were carried out in 2010 and 2011 in the German Bight (southern North Sea) at two sites approx. 20 km offshore of the island of Sylt. Abiotic and biotic seabed facies, such as sorted bedforms, areas of fine to medium sand and L. conchilega beds with different tube densities, were identified and characterised based on manual expert analysis and image texture analysis. Ground truthing was performed by grab sampling and underwater video observations. Compared to the manual expert analysis, the k-means classification of image textures proves to be a semi-automated method to investigate small-scale differences in a biologically altered seabed from backscatter data. The texture parameters entropy and homogeneity appear linearly interrelated with tube density, the former positively and the latter negatively. Reinvestigation of one site after 1 year showed an extensive change in the distribution of the L. conchilega-altered seabed. Such marked annual fluctuations in L. conchilega tube cover demonstrate the need for dense time series and high spatial coverage to meaningfully monitor ecological patterns on the seafloor with acoustic backscatter methods in the study region and similar settings worldwide, particularly because the sand mason plays a pivotal role in promoting biodiversity. In this context, image texture analysis provides a cost-effective and reproducible method to track biologically altered seabeds from side scan sonar backscatter signatures. © 2016 Springer-Verlag Berlin Heidelberg


Schernewski G.,Leibniz Institute for Baltic Sea Research | Schernewski G.,Klaipeda University | Friedland R.,Leibniz Institute for Baltic Sea Research | Carstens M.,State Agency for Environment | And 9 more authors.
Marine Policy | Year: 2015

A full re-calculation of Water Framework Directive reference and target concentrations for German coastal waters and the western Baltic Sea is presented, which includes a harmonization with HELCOM Baltic Sea Action Plan (BSAP) targets. Further, maximum allowable nutrient inputs (MAI) and target concentrations in rivers for the German Baltic catchments are suggested. For this purpose a spatially coupled, large scale and integrative modeling approach is used, which links the river basin flux model MONERIS to ERGOM-MOM, a three-dimensional ecosystem model of the Baltic Sea. The years around 1880 are considered as reference conditions reflecting a high ecological status and are reconstructed and simulated with the model system. Alternative approaches are briefly described, as well. For every WFD water body and the open sea, target concentrations for nitrogen and phosphorus compounds as well as chlorophyll a are provided by adding 50% to the reference concentrations. In general, the targets are less strict for coastal waters and slightly stricter for the sea (e.g. 1.2. mg/m3 chl.a summer average for the Bay of Mecklenburg), compared to current values. By taking into account the specifics of every water body, this approach overcomes the inconsistencies of earlier approaches. Our targets are well in agreement with the BSAP targets, but provide spatially refined and extended results. The full data are presented in Appendix A1 and A2.To reach the targets, German nitrogen inputs have to be reduced by 34%. Likely average maximum allowable concentrations in German Baltic rivers are between 2.6 and 3.1 mg N/l. However, the concrete value depends on the scenario and uncertainties with respect to atmospheric deposition. To our results, MAI according to the BSAP may be sufficient for the open sea, but are not sufficient to reach a good WFD status in German coastal waters. © 2014 The Authors.


Schubert P.R.,Leibniz Institute of Marine Science | Karez R.,State Agency for Agriculture | Reusch T.B.H.,Leibniz Institute of Marine Science | Dierking J.,Leibniz Institute of Marine Science
Marine Pollution Bulletin | Year: 2013

Eutrophication is a global environmental problem. Better management of this threat requires more accurate assessments of anthropogenic nitrogen (N) inputs to coastal systems than can be obtained with traditional measures. Recently, primary producer N isotopic signatures have emerged as useful proxy of such inputs. Here, we demonstrated for the first time the applicability of this method using the widespread eelgrass (Zostera marina) in the highly eutrophic Baltic Sea. Spatial availability of sewage N across a bay with one major sewage outflow predicted by eelgrass δ15N was high near and downstream of the outflow compared to upstream, but returned to upstream levels within 4km downstream from the outfall. General conclusions were corroborated by traditional eutrophication measures, but in contrast to these measures were fully quantitative. Eelgrass N isotope ratios therefore show high potential for coastal screens of eutrophication in the Baltic Sea, and in other areas with eelgrass meadows. © 2013 Elsevier Ltd.


PubMed | State Agency for Environment, Leibniz Institute for Baltic Sea Research and State Agency for Agriculture
Type: Journal Article | Journal: Marine pollution bulletin | Year: 2015

Full-coverage maps on the distribution of marine biotopes are a necessary basis for Nature Conservation and Marine Spatial Planning. Yet biotope maps do not exist in many regions. We are generating the first full-coverage biotope map for the German Baltic Sea according to the HELCOM Underwater biotope and habitat classification system (HUB). Species distribution modelling is applied to create full-coverage spatial information of biological features. The results of biomass modelling of twelve target taxa and presence/absence modelling of three target taxa enabled the identification of biological levels up to HUB level 6. Environmental data on bathymetry, light penetration depth and substrate are used to identify habitat levels. HUB biotope levels were combined with HUB habitat levels to create a biotope map. Altogether, 68 HUB biotopes are identified in the German Baltic Sea. The new biotope map combining substrate characteristics and biological communities will facilitate marine management in the area.


PubMed | Leibniz Institute of Marine Science and State Agency for Agriculture
Type: Journal Article | Journal: Marine pollution bulletin | Year: 2015

Seagrass meadows, one of the worlds most important and productive coastal habitats, are threatened by a range of anthropogenic actions. Burial of seagrass plants due to coastal activities is one important anthropogenic pressure leading to the decline of local populations. In our study, we assessed the response of eelgrass Zostera marina to sediment burial from physiological, morphological, and population parameters. In a full factorial field experiment, burial level (5-20cm) and burial duration (4-16weeks) were manipulated. Negative effects were visible even at the lowest burial level (5cm) and shortest duration (4weeks), with increasing effects over time and burial level. Buried seagrasses showed higher shoot mortality, delayed growth and flowering and lower carbohydrate storage. The observed effects will likely have an impact on next years survival of buried plants. Our results have implications for the management of this important coastal plant.


PubMed | Schleswig Holstein Agency for Coastal Defence, State Agency for Agriculture, National Park Authority Wadden Sea of Lower Saxony, University of Hamburg and Brockmann Consult GmbH
Type: Journal Article | Journal: Environmental monitoring and assessment | Year: 2016

The Wadden Sea along the North Sea coasts of Denmark, Germany, and the Netherlands is the largest unbroken system of intertidal sand and mud flats in the world. Its habitats are highly productive and harbour high standing stocks and densities of benthic species, well adapted to the demanding environmental conditions. Therefore, the Wadden Sea is one of the most important areas for migratory birds in the world and thus protected by national and international legislation, which amongst others requires extensive monitoring. Due to the inaccessibility of major areas of the Wadden Sea, a classification approach based on optical and radar remote sensing has been developed to support environmental monitoring programmes. In this study, the general classification framework as well as two specific monitoring cases, mussel beds and seagrass meadows, are presented. The classification of mussel beds profits highly from inclusion of radar data due to their rough surface and achieves agreements of up to 79% with areal data from the regular monitoring programme. Classification of seagrass meadows reaches even higher agreements with monitoring data (up to 100%) and furthermore captures seagrass densities as low as 10%. The main classification results are information on area and location of individual habitats. These are needed to fulfil environmental legislation requirements. One of the major advantages of this approach is the large areal coverage with individual satellite images, allowing simultaneous assessment of both accessible and inaccessible areas and thus providing a more complete overall picture.

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