The accelerated rate of climate change questions the capacity of current infrastructures to adapt to altered future climate conditions, specifically in areas prone to floods, such as the Rhine-Meuse-Scheldt delta. Simultaneously the unforeseen effects of ‘hard’ engineering approaches (such as dams, storm surge barriers, defensive coastal management) have been affecting biophysical as well as ecological systems, resulting in increased vulnerability to floods and loss of estuarine habitats. Therefore there appears to be a need to rethink coastal (protection) strategies.

The project relates to the temporal and spatial distributions of socio-economic as well as ecological vulnerabilities under the influence of increased flood probability and climatic stressors in the Rhine-Meuse-Scheldt delta, questioning how a nature-based approach can be used to support the adaptive capacity of the delta and mitigation of altered future climate conditions. It specifically explores the development of critical land-water zones adjacent to the Eastern Scheldt, and construction of a framework for decision making in which nature-based solutions are prioritized. Initial stressing factors as well as space availability indicate the preferred solution space both landwards and seawards over the consolidation of the existing line. As means to structure proposals an adaptive framework has been developed on the scale of Schouwen Duiveland to maintain the existing qualities of the island, as well as selecting and excluding a solution pathway based on the systemic functioning of the island. The approach stands closely to the the notion that humans are an intrinsic part of nature. Therefore developments related to water safety, fresh water supply and critical infrastructures should act in accordance to the acceptance of dynamics as apposed to the idea of presumed stability.

Background: A central theme in (micro)biology is understanding the molecular basis of fitness i.e. which strategies are successful under which conditions; how do organisms implement such strategies at the molecular level; and which constraints shape the trade-offs between alternative strategies. Highly standardized microbial laboratory evolution experiments are ideally suited to approach these questions. For example, prolonged chemostats provide a constant environment in which the growth rate can be set, and the adaptive process of the organism to such environment can be subsequently characterized. Results: We performed parallel laboratory evolution of Lactococcus lactis in chemostats varying the quantitative value of the selective pressure by imposing two different growth rates. A mutation in one specific amino acid residue of the global transcriptional regulator of carbon metabolism, CcpA, was selected in all of the evolution experiments performed. We subsequently showed that this mutation confers predictable fitness improvements at other glucose-limited growth rates as well. In silico protein structural analysis of wild type and evolved CcpA, as well as biochemical and phenotypic assays, provided the underpinning molecular mechanisms that resulted in the specific reprogramming favored in constant environments. Conclusion: This study provides a comprehensive understanding of a case of microbial evolution and hints at the wide dynamic range that a single fitness-enhancing mutation may display. It demonstrates how the modulation of a pleiotropic regulator can be used by cells to improve one trait while simultaneously work around other limiting constraints, by fine-tuning the expression of a wide range of cellular processes.

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