Weichholzauen-Entwicklung als Beitrag zum naturverträglichen Hochwasserschutz im Biosphärenreservat Mittelelbe

Die Gefährdung von Auen mit ihren typischen Vegetationsgesellschaften beruht vor allem auf dem Ausbau der Flüsse zu Wasserstraßen, einhergehend mit dem Bau von Dämmen, Staustufen, Deichen und Uferbefestigungen. Der Ausbau der Wasserstraßen hat weitreichende Konsequenzen für die Hydrodynamik des Flusses, die Geomorphologie und die hydrologischen Bedingungen in der Aue. Ein Lebensraumtypus, der dabei in besonderem Maße betroffen ist, sind die Weichholzauen. Während vor wenigen Jahrhunderten die Vorländer der Elbe noch größere Bestände von Weichholz- und Hartholzauen aufwiesen, ist das heutige Landschaftsbild vor allem durch extensiv genutzte Grünländer geprägt. Weichholzauenwälder sind als prioritär zu schützender, natürlicher Lebensraumtyp eingestuft und besitzen eine besondere Schutz- und Entwicklungsbedürftigkeit. Weichholzauenwälder bieten nicht nur Lebensraum für viele seltene Tier- und Pflanzenarten, sie beeinflussen auch den Nährstoffkreislauf innerhalb der Aue, haben einen wichtigen Einfluss auf die Wasserqualität und stabilisieren Ufer- und Vorlandbereiche. Zudem dienen sie als Retentionsraum und können damit zum Hochwasserschutz beitragen. Vor diesem Hintergrund förderte die Deutsche Bundesstiftung Umwelt (DBU) das interdisziplinäre Projekt „KoWeB – Konzept zur Weichholzauen- Entwicklung als Beitrag zum naturverträglichen Hochwasserschutz an Bundeswasserstraßen“ in der Laufzeit 2006 bis 2009. Das Ziel war die Entwicklung einer praxistauglichen Methode zur Identifizierung von Flächen zur Ansiedlung von Weichholzauen in Überschwemmungsgebieten unter Beachtung der ökologischen Kriterien und der Hochwasserneutralität

Habitat distribution and population genetics of riparian Salix species in space and time – a restoration framework for softwood forests along the Elbe River

Riparian softwood forests belong to the most endangered vegetation types in Central Europe due to diverse river management measures (e.g. dyking, river training, etc.). As unmodified hydro-geomorphic processes along rivers are widely lacking, which are necessary to create competition-free establishment sites, natural regeneration of the respective species is almost absent. Hence, restoration measures are required but are a challenging task given species’ ecological requirements as well as the different interests of economy, society, and nature conservation. My thesis was conducted within the framework of a project to develop a concept for the establishment of riparian softwood forests combining ecological and flood protection issues along the Middle Elbe River. Main aims were to investigate ecological as well as population genetic aspects of riparian softwood forest species to deliver a basis for improving the success of restoration measures such as plantings. Five studies were conducted dealing with different aspects of riparian softwood forest restoration. In the first study the ecological relationships of distribution patterns of riparian softwood forests and hydrological variables were examined on the basis of habitat distribution models, which were developed for two softwood vegetation types as well as two age classes. They revealed that hydrological variables are significantly related to and substantially determine species distribution. Based on the observed ecological patterns advices are given for the selection of suitable planting sites. In the second study, an experimental approach, potential effects of competition and biomass loss on the regeneration capability of vegetative propagules, i.e. cuttings, of diverse riparian Salix species were tested. It revealed that cuttings, similarly as seedlings, are prone to competition mainly due to demands for light, indicating that competition should be eliminated during establishment phases to increase the success of planting measures. The additionally tested resprouting ability of the species disclosed vigorous growth capacities of all investigated floodplain species making them particularly suitable for restoration purposes. Since much debate exists on softwood forest restoration plantings from a flood protections point of view the third study was conducted to assess the effect of riparian softwood forest plantings on flooding risk combining habitat distribution models as well as a two-dimensional hydraulic-numerical model. With this approach we could demonstrate that it is possible to identify sites which meet the criteria of both ecological as well as hydraulic suitability. Hence, substantial potential for “safe” plantings can be expected in managed river-floodplain systems. The fourth study dealt with possible effects of climate change on habitat distribution of riparian softwood forest species. While current conditions still disclose large potential for softwood forest restoration, habitat projections based on climate change induced hydrological alterations point to a further loss of suitable habitat in the future. Great uncertainty in habitat availability for restoration measures due to substantial variability in hydrological projections exists. However, this uncertainty should be implemented into restoration management to preserve riparian softwood forests in the long term. While current natural population structures and dynamics of riparian softwood forest species warn about an extremely critical condition regarding the long-term persistence of these vegetation types, results of the fifth study, a genetic population analysis, are less alarming. Clonal patterns and genetic diversity of Salix viminalis as a model species were investigated as basis for the selection of suitable planting material. Though clonal structures were prevalent no dominance of single clones was detected. Levels of genetic diversity were generally high and no negative effects of floodplain or stand fragmentation on diversity levels were found. From the observed genetic patterns, advices for the selection of planting material are deduced. Overall, the results presented in this thesis deliver a sound basis for the restoration of riparian softwood forests based on reforestation. Given the restricted sustainability of these measures additionally other restoration approaches should be considered enabling the “re-dynamisation” of the floodplain and hence the self-preservation of riparian softwood forests

No Need to Be Boxed in: Group Pens and Grain for Veal Calves

The author’s family has been in the wholesale veal business for 30 years. The basis of this business has been various breeds of female beef calves that are slaughtered at less than 500 lb. These calves are allowed to suck from cows and graze until they are ready for market. However, beef calves tend to vary in quality and quantity depending on the time of the year they are purchased and raised. Generally, calves become scarce in the spring, when feeders are buying calves to put out on pasture. The author comments on the future of the veal industry

No Need to Be Boxed in: Group Pens and Grain for Veal Calves

My family has been in the wholesale veal business for 30 years. The basis of this business has been various breeds of female beef calves that are slaughtered at less than 500 lb. These calves are allowed to suck from cows and graze until they are ready for market. Beef calves, however, tend to vary in quality and quantity depending on the tjme of the year that they are purchased and raised. Generally, calves become scarce in the spring, when feeders are buying calves to put out on pasture. Then, in the summer and fall, large numbers of calves usually become available, thereby depressing prices. Again, in the winter, calves become scarcer and consequently more expensive

Association between the oxytocin receptor (OXTR) gene and mesolimbic responses to rewards

10.1186/2040-2392-5-7Molecular Autism51

Social and Nonsocial Effort-Based Decision-Making in Adolescents with Autism Spectrum Disorders

There has been recent emphasis on addressing the impact of motivational factors on social deficits in Autism spectrum disorders (ASD). The present investigation evaluated effort-based decision-making in social and nonsocial contexts to examine one aspect of social motivation in ASD. To downward extend prior findings of impaired effort-expenditure in adults with ASD, the current study explored effort-based decision-making in adolescents with ASD and typically developing adolescents. Using the Effort Expenditure for Rewards Task (EEfRT), participants made choices to win money for themselves or to win money for another person. Contrary to previous findings, when choosing for themselves, the ASD group exhibited similar effort-expenditure across reward parameters compared to typical adolescents. However, when choosing for another person, the ASD group demonstrated decreased sensitivity to reward magnitude. These findings provide support for atypical social effort-based decision-making in this population and highlight the importance of exploring developmental patterns of reward processing in ASD.Master of Art

How Middle Managers Affect Frontline Idea Generation: Evidence From Healthcare Operations

This multiple case study develops a mid-range theory on how frontline idea generation is affected by the actions of an organization's middle management. The study draws from four acute-care hospitals in Germany and involves 36 semi-structured interviews with representatives from all hierarchy levels. We use mission statements from these hospitals to measure top management's strategic intent regarding frontline idea generation. Then we analyze the idea generation performance of 156 nurses from the hospitals and link it to specific middle management behaviors. The cross-case analyses reveal that middle managers' shaping of nurses' innovation identity improves nurses' idea generation performance. However, this connection also means that middle managers' own forays into innovation can impede frontline idea generation. We find that middle managers' supportive behavior is largely independent of top management intent, a dynamic that offers both advantages and risks. These insights extend our knowledge about the role of middle managers in frontline idea generation