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Die vorliegende Publikation versteht sich als Ideengeber für die universitäre Lehre in der Lehrerbildung in Gestalt eines sogenannten Transferpakets. Sie berichtet über Ergebnisse des Teilprojekts ‚Spotlights-Lehre‘ des Projekts ‚Schnittstellen gestalten – Lehrerbildung entlang des Leitbildes des "Reflective Practitioner" an der Universität Bremen' im BMBF-Programm ‚Qualitätsoffensive Lehrerbildung‘. Inhaltlich geht es um innovative Lehrprojekte zur Verzahnung und Vernetzung von Fachwissenschaft und Fachdidaktik, die das Ziel verfolgen, Fragmentierungserfahrungen von Lehramtsstudierenden in den Fächern Mathematik, Englisch, Romanistik, Geschichte und Inklusive Didaktik zu reduzieren. Zentrales Anliegen dieses Transferpakets ist es, Transferstrategien bereitzustellen, an Beispielen zu illustrieren und in Lehrbeschreibungen einzubetten. Umfassend wird gezeigt, wie die Designprozesse zur Lehre in den beiden zentralen Modellprojekten der Fächer Englisch und Mathematik gestaltet sowie die Transfer- und Vernetzungsstrategien gewonnen wurden.

The Wadden Sea is one of the most important stop-over sites for migrating and breeding birds. About 10-12 million birds per year use the area for foraging and consume about 25 to 45% of the standing stock of macrozoobenthos. But little is known about the influence of birds on the entire ecosystem. We conducted Ecological Network Analysis (ENA) in an important breeding and resting site in the north-eastern German Wadden Sea to determine the influence of birds on the food web. The model was based on the yearly average of empirical data taken in the study site. In its current condition, the system appears to be in a well-balanced status, with a relative Ascendency of 32.3% and a robustness of 36.5%. The diversity of flows was high showed by a Flow Diversity of 5.1 and numerous parallel pathways represented by an Effective Link-Density of 3.3. A large variety of different bird species uses the area for foraging. As top predators, these bird species are included directly or indirectly in most of the pathways. Birds induce a huge negative impact on their prey items with a less pronounced positive feedback reaction to the competitors and food resources of those organisms. There is also a strong negative impact among the bird compartments probably due to competition between the bird species on the intertidal flats. Changes in the biomass of the birds revealed alterations in the food web structure. With a decline in the avian biomass the system showed a decrease in connectivity and diversity of flows but an increase in recycling. Birds therefore appear to be an important factor for the food web structure. Changes in the bird population could affect the complexity and functioning of the entire ecosystem. Thus, it is recommended to include birds in coastal food web studies which has rarely been done before. The use of such holistic approaches would facilitate undertaking management measures.

The Wadden Sea is one of the most important stop-over sites for 10 to 12 Million migrating birds per year. But little is known about the influence of birds on the entire ecosystem. We conducted Ecological Network Analysis (ENA) in an important resting site in the Wadden Sea to determine the influence of birds on the food web. A large variety of different bird species uses the area for foraging and is included directly or indirectly in most of the pathways. Birds induce a negative impact on their prey items with a positive feedback reaction to the preys’ competitors and food sources. There is also a strong negative impact among the bird compartments probably due to competition between the birds. Changes in the biomass of the birds revealed alterations in the food web structure. With a decline in the avian biomass the system showed a decrease in connectivity and diversity of flows but an increase in recycling. Changes in the bird population could affect the complexity and functioning of the entire ecosystem. Thus, the use of such holistic approaches would facilitate undertaking management measures.

Ecological network analysis (ENA) is a helpful tool to study complex ecosystem processes. The diverse species interactions are described as flows of energy providing a simplified representation of the natural system based on attributes and features. In the Wadden Sea, a unique ecosystem along the coastline of Denmark, Germany and the Netherlands, physical forces form the vast intertidal areas to diverse habitat types that differ in their species composition and abundance. Those habitats are important foraging areas for top predators such as birds. In the present study the food web of six habitats characteristic for the Wadden Sea (cockle field, razor clam field, mud flat, mussel bank, sand flat and seagrass meadow) were analyzed in a modelling approach. The functional and structural properties of the food webs were compared to assess differences and similarities in the system functioning. Although all systems revealed a good balance between their degree of organization and their robustness against external perturbations, they differed in their detailed features. The cockle field and the mussel bank both exhibited a strong dependence of their efficiency on external imports. The razor clam field, dominated by the introduced species Ensis directus, appeared to be a rather small and stressed system with low energy transfer. The mud flat system was characterized by a high use of microphytobenthos and appeared to be not fully developed yet. Bird predation was most pronounced in the sand flat and the seagrass meadow and led to an increase in energy transfer, parallel pathways and pathways lengths in these habitats. Each system shows characteristic features and plays a different role in the Wadden Sea ecosystem by contributing significantly to the whole system functioning.

Illustrationen, Diagramme, Karten

The Wadden Sea is a unique coastal ecosystem and of outstanding importance for millions of coastal birds which use the intertidal area as a major food source. In this study the importance of habitat diversity and the influence of avian predators on the intertidal food web was determined using Ecological Network Analysis. Similarities and differences of the food web structure were analyzed for six different intertidal habitats (i.e. cockle field, razor clam field, mud flat, mussel bank, sand flat, seagrass meadow). All systems were in a good trade-off between their degree of order and their redundancy implying a sustainable system structure and resistance in front of perturbations. But the habitats differed in their detailed features. The cockle field and the mussel bank were characterized by a complex and diverse flow structure while being simultaneously strongly dependent on external phytoplankton imports. Razor clam fields were revealed to be simple but very efficient systems. The studied mud flat appeared to be vulnerable to perturbations due to short and simple pathways and little recycling. The sand flat and the seagrass meadow showed a complex and redundant flow structure and a high recycling indicating independence and resistance. Habitat diversity appears to be an important trait for the Wadden Sea food web as each habitat has a distinct role in the whole ecosystem functioning. Furthermore, the diverse habitats are of great importance for foraging bird which might be specialized to one of the habitats. Birds induce a large impact on the Wadden Sea food web. Due to their various direct and indirect influences, it is likely that changes in the bird population also cause changes in the whole system functioning. A decline in birds results in a decrease of pathway length and a less redundant and diverse flow structure. Birds therefore play an important role in stabilizing the intertidal food web. The holistic approach of Ecological Network Analysis provides fundamental insight in the Wadden Sea food web structure. Results of this thesis are a useful basis to develop management tools and strategies for assessing the ecological state and the health of this unique ecosystem.

The Wadden Sea is one of the most important foraging areas for breeding and migrating birds. However, little is known about the preferred feeding places of birds and how the intense predation pressure influences the food web. Within the project STopP the trophodynamic structure of different Wadden Sea habitats is determined to get an idea how sediment characteristics and hydrodynamics modify habitats that serve as food sources for birds.

The Wadden Sea at the western coasts of Germany, Denmark and the Netherlands is one of the globally most important foraging areas for breeding and migrating birds which act at the same time as indicators for the ecological condition of the ecosystem. However, little is known about how the intense predation pressure of birds influences the Wadden Sea food web. The aim of the interdisciplinary project STopP (From Sediment to Top Predator) is to determine the food web structure in different Wadden Sea habitat types in terms of the interaction between the basis of the food web and birds as top predators. Studied habitat types included the most important foraging areas of birds; mussel banks, cockle beds, sand flats, mud flats, seagrass meadows and beds of the immigrant razor clam Ensis directus a recently preferred prey item of several bird species. Data were analysed using the Ecological Network Analysis (ENA) that reflects trophic structures within the systems and reveals direct and indirect relations between the lower and the upper trophic levels. Preliminary results show that bird predation increases the complexity of the food web due to an increase in connections and a higher total system throughput. On the other hand the predation has also a destabilizing effect due to a high demand of system’s carbon stocks and increased exports out of the tidal system. In addition, analyses show considerable indirect dependencies of birds to lower trophic levels such as sediment POC and phytoplankton. Future scenarios modelled with ENA shall show how changes within the lower trophic levels would affect foraging birds due to anthropogenic or natural impacts. Further analysis will focus on the importance of special habitat types for different bird species and the influence of changes in the biomass of key species for the whole ecosystem food web.

The Wadden Sea at the western coasts of Germany, Denmark and the Netherlands is one of the globally most important foraging areas for breeding and migrating birds acting as indicators for the ecological condition of the ecosystem. However, little is known about how the intense predation pressure of birds influences the Wadden Sea food web. The aim of the interdisciplinary project STopP is to determine the food web structure in terms of the interaction between the basis of the food web and birds as top predators. Studied habitat types included the most important foraging areas of birds; mussel banks, cockle beds, sand flats, mud flats, seagrass meadows and beds of the immigrant razor clam Ensis directus a recently preferred prey item of several bird species. Data were analysed using the Ecological Network Analysis (ENA) that reflects trophic structures within the systems and reveals direct and indirect relations between the lower and the upper trophic levels. Preliminary results show that bird predation increases the complexity of the food web due to an increase in connections and a higher total system throughput. On the other hand the predation has also a destabilizing effect due to a high demand of system’s carbon stocks and increased exports out of the tidal system. Furthermore, analyses show considerable indirect dependencies of birds to lower trophic levels such as sediment POC and phytoplankton. Future scenarios modelled with ENA shall show how changes within the lower trophic levels would affect foraging birds due to anthropogenic or natural impacts.

The Wadden Sea is one of the most important foraging areas for breeding and migrating birds. However, little is known about the preferred feeding places of birds and how the intense predation pressure influences the food web. The aim of the STopP project is to determine the structure of the Wadden Sea food web and how sediment characteristics and hydrodynamics modify habitats that deal as food sources for birds.

An imbalance of angiogenic and antiangiogenic placental factors such as endoglin and soluble fms-like tyrosine kinase 1 has been implicated in the pathophysiology of preeclampsia. Extraction of these substances by plasmapheresis might be a therapeutical approach in cases of severe early-onset preeclampsia. Case Report. A 21-year-old primigravida with antiphospholipid syndrome developed early-onset preeclampsia at 18 weeks’ gestation. She was treated successfully with plasmapheresis in order to prolong pregnancy. Endoglin and sflt-1-levels were measured by ELISA before and after treatment. Endoglin levels decreased significantly after treatment (p < 0.05) and showed a significant decrease throughout pregnancy. A rerise of endoglin and sflt-1 preceded placental abruption 4 weeks before onset of incident. Conclusion. Due to the limited long-term therapeutical possibilities for pregnancies complicated by PE, plasmapheresis seems to be a therapeutical option. This consideration refers especially to pregnancies with early-onset preeclampsia, in which, after first conventional treatment of PE, prolongation of pregnancy should be above all.