Getting grip on complex water issues? : a case study: Rotterdam Mainport, Appropriate Assessment Wadden Sea

In Dutch water systems many human interventions are carried out. These interventions are designed to achieve management goals, like increase protection against flooding, improve environmental quality and/or stimulate the national economy. Decision-makers involved in these kinds of plans have to deal with ecological effects, physical effects, economic costs and benefits and technical feasibility. Furthermore, they operate within a complex web of interactions between policy, regulations, and social and political processes. This PhD-project aims at assisting decision-makers in constructing assessments of the impact of future human interventions in water systems

Knowledge and perceptions in participatory policy processes: lessons from the delta-region in the Netherlands

Water resources management issues tend to affect a variety of uses and users. Therefore, they often exhibit complex and unstructured problems. The complex, unstructured nature of these problems originates from uncertain knowledge and from the existence of divergent perceptions among various actors. Consequently, dealing with these problems is not just a knowledge problem; it is a problem of ambiguity too. This paper focuses on a complex, unstructured water resources management issue, the sustainable development—for ecology, economy and society—of the Delta-region of the Netherlands. In several areas in this region the ecological quality decreased due to hydraulic constructions for storm water safety, the Delta Works. To improve the ecological quality, the Dutch government regards the re-establishment of estuarine dynamics in the area as the most important solution. However, re-establishment of estuarine dynamics will affect other uses and other users. Among the affected users are farmers in the surrounding areas, who use freshwater from a lake for agricultural purposes. This problem has been addressed in a participatory decision-making process, which is used as a case study in this paper. We investigate how the dynamics in actors’ perceptions and the knowledge base contribute to the development of agreed upon and valid knowledge about the problem–solution combination, using our conceptual framework for problem structuring. We found that different knowledge sources—expert and practical knowledge—should be integrated to create a context-specific knowledge base, which is scientifically valid and socially robust. Furthermore, we conclude that for the convergence of actors’ perceptions, it is essential that actors learn about the content of the process (cognitive learning) and about the network in which they are involved (strategic learning). Our findings form a plea for practitioners in water resources management to adopt a problem structuring approach in order to deal explicitly with uncertainty and ambiguity

Comparing Behavioural Heterogeneity Across Asset Classes

We estimate an endowment-based asset pricing model in which agents have heterogeneous and time-varying beliefs about the future price on a range of asset classes. This gives insight into the extent behaviour differs across assets, and what this implies for market stability. We find evidence for behavioural heterogeneity for all asset classes but equity. Heterogeneity is especially large and persistent in asset classes for which limits to arbitrage are more binding. In less constrained (financial) markets, agents update their beliefs more frequently. Consequently, the probability of behavioural bubbles and crashes is substantially higher in macroeconomic asset classes than in financial asset classes

Morphodynamic models used to study the impact of offshore aggregate extraction:A review

http://www.cerf-jcr.org/images/stories/17127-4%20idier%20web%20only.pdfInternational audienceThis review highlights three morphodynamics modelling approaches, used for offshore marine aggregate extraction impact assessment. These approaches are based upon examples of (1) full process-based models; (2) idealised processbased models; and (3) conceptual models. Illustrated also is the way in which these models, applied for extractions on flat bed or sandbanks, can complement each other, towards the estimation of Coastal State Indicators (CSIs). This review leads to the conclusion that, for an optimal environment assessment, there are two main approaches: (1) either combine and couple the models, in order to simulate the full morphodynamics of the system over a long time-scale, taking into account also short-term events, or (2) use a set of existing models, knowing precisely their applicability to the CSI's and the reliability of their predictions, rather than using only the best model, available presently

Farnesoid X Receptor (FXR) Activation and FXR Genetic Variation in Inflammatory Bowel Disease

Contains fulltext : 96924.pdf (publisher's version ) (Open Access)BACKGROUND: We previously showed that activation of the bile salt nuclear receptor Farnesoid X Receptor (FXR) protects against intestinal inflammation in mice. Reciprocally, these inflammatory mediators may decrease FXR activation. We investigated whether FXR activation is repressed in the ileum and colon of inflammatory bowel disease (IBD) patients in remission. Additionally, we evaluated whether genetic variation in FXR is associated with IBD. METHODS: mRNA expression of FXR and FXR target gene SHP was determined in ileal and colonic biopsies of patients with Crohn's colitis (n = 15) and ulcerative colitis (UC; n = 12), all in clinical remission, and healthy controls (n = 17). Seven common tagging SNPs and two functional SNPs in FXR were genotyped in 2355 Dutch IBD patients (1162 Crohn's disease (CD) and 1193 UC) and in 853 healthy controls. RESULTS: mRNA expression of SHP in the ileum is reduced in patients with Crohn's colitis but not in patients with UC compared to controls. mRNA expression of villus marker Villin was correlated with FXR and SHP in healthy controls, a correlation that was weaker in UC patients and absent in CD patients. None of the SNPs was associated with IBD, UC or CD, nor with clinical subgroups of CD. CONCLUSIONS: FXR activation in the ileum is decreased in patients with Crohn's colitis. This may be secondary to altered enterohepatic circulation of bile salts or transrepression by inflammatory signals but does not seem to be caused by the studied SNPs in FXR. Increasing FXR activity by synthetic FXR agonists may have benefit in CD patients

Complexe waterbeheervraagstukken

Begin september 2008 bracht de Deltacommissie 2, onder leiding van oud-minister Veerman, haar advies uit over de bescherming tegen de gevolgen van klimaatverandering. De reacties op dit advies waren in eerste instantie lovend, maar deze geluiden maakten al snel plaats voor kritiek uit allerlei windrichtingen. Waarom gaat de commissie uit van een worstcase scenario van 130 centimeter zeespiegelstijging per eeuw? Zijn de financiën wel goed afgedekt? Is de peilverhoging van 1,5 meter in het IJsselmeer niet desastreus voor de dorpen en steden aan het meer? Wat is er gebeurd met de overgang naar ‘risico-denken’ in plaats van ‘kansdenken’? En hoe zit het met het onderhoud van onze dijken? Door al deze kritiek kan men zich afvragen of de Deltacommissie haar werk wel goed heeft gedaan. Deze uiteenlopende kritieken zijn echter inherent aan complexe vraagstukken, omdat elke partij zijn of haar eigen perceptie van de waterproblematiek heeft en er onzekerheid bestaat over onze kennis van het watersysteem, zeker op de lange termijn. Door het advies van de commissie is een open discussie gestart, die nodig is om dit soort complexe waterbeheervraagstukken op te kunnen lossen. Dit is althans hoe ik er tegenaan kijk vanuit mijn promotieonderzoek bij de vakgroep Waterbeheer

Role of stakeholders' perspectives in complex water issues : A case study: Project Mainport Rotterdam, Appropriate Assessment Wadden Sea

This report describes the case study research on the Appropriate Assessment Wadden Sea, that is conducted by Ir Saskia Hommes as part of her PhD-project, as complete as possible. In the period from April to November 2005, the researcher participated in the project Appropriate Assessment Wadden Sea, which is part of Project Mainport Rotterdam, by attending and observing project meetings. And from October 2005 to July 2006, the researcher conducted interviews with participants of the project