Analyzing Collaborative Governance Through Social Network Analysis: A Case Study of River Management Along the Waal River in The Netherlands

Until recently, governmental organizations played a dominant and decisive role in natural resource management. However, an increasing number of studies indicate that this dominant role is developing towards a more facilitating role as equal partner to improve efficiency and create a leaner state. This approach is characterized by complex collaborative relationships between various actors and sectors on multiple levels. To understand this complexity in the field of environmental management, we conducted a social network analysis of floodplain management in the Dutch Rhine delta. We charted the current interorganizational relationships between 43 organizations involved in flood protection (blue network) and nature management (green network) and explored the consequences of abolishing the central actor in these networks. The discontinuation of this actor will decrease the connectedness of actors within the blue and green network and may therefore have a large impact on the exchange of ideas and decision-making processes. Furthermore, our research shows the dependence of non-governmental actors on the main governmental organizations. It seems that the Dutch governmental organizations still have a dominant and controlling role in floodplain management. This challenges the alleged shift from a dominant government towards collaborative governance and calls for detailed analysis of actual governance.

Combining safety and nature: a multi-stakeholder perspective on integrated floodplain management

In The Netherlands, river management strategies and land use of floodplains have changed drastically over the last two decades. Due to an integrated and participatory planning style, many agricultural fields in floodplains were transformed to nature. The idea of "self-regulating nature" in the floodplains and policies such as Room for the River and WaalWeelde created more multifunctional and natural floodplains. In this way, during the planning phase, win-win situations were created between flood protection and nature. It was only later that obstacles occurred with regard to the maintenance of floodplains, mainly because of different perspectives of the stakeholders on how to reconcile flood protection and nature. Therefore this study focuses on the opinions of persons involved with 'future' floodplain management strategies, which have been divided into five themes: ·visions of floodplain management; ·collaborators in floodplain management; ·visions of nature and self-regulating nature; ·realization of Natura 2000 goals in floodplains; ·feasibility of the Cyclic Floodplain Rejuvenation (CFR) strategy. We interviewed various persons involved in river and nature management along the Waal River. Based on our findings, it is concluded that an integrated planning approach has not been incorporated into the maintenance strategies and programs and, as a result, new, innovative management strategies such as CFR are proving to be incompatible with 'static' regulations such as Natura 2000's conservation goals and flood protection norms. However, by exploring the responders' visions of nature, we found that the majority of them preferred a dynamic vision of floodplains and, for this reason, they have advocated for more flexibility in current policies related to river and nature management. Additionally, the respondents emphasized the importance of multi-stakeholder collaboration to realize the goal of cost-efficient floodplain management.

Differences in flooding tolerance between species from two wetland habitats with contrasting hydrology: implications for vegetation development in future floodwater retention areas

BACKGROUND AND AIMS

Plants need different survival strategies in habitats differing in hydrological regimes. This probably has consequences for vegetation development when former floodplain areas that are currently confronted with soil flooding only, will be reconnected to the highly dynamical river bed. Such changes in river management are increasingly important, especially at locations where increased water retention can prevent flooding events in developed areas. It is therefore crucial to determine the responses of plant species from relatively low-dynamic wetlands to complete submergence, and to compare these with those of species from river forelands, in order to find out what the effects of such landscape-scale changes on vegetation would be.

METHODS

To compare the species' tolerance to complete submergence and their acclimation patterns, a greenhouse experiment was designed with a selection of 19 species from two contrasting sites: permanently wet meadows in a former river foreland, and frequently submerged grasslands in a current river foreland. The plants were treated with short (3 weeks) and long (6 weeks) periods of complete submergence, to evaluate if survival, morphological responses, and changes in biomass differed between species of the two habitats.

KEY RESULTS

All tested species inhabiting river forelands were classified as tolerant to complete submergence, whereas species from wet meadows showed either relatively intolerant, intermediate or tolerant responses. Species from floodplains showed in all treatments stronger shoot elongation, as well as higher production of biomass of leaves, stems, fine roots and taproots, compared with meadow species.

CONCLUSIONS

There is a strong need for the creation of temporary water retention basins during high levels of river discharge. However, based on the data presented, it is concluded that such reconnection of former wetlands (currently serving as meadows) to the main river bed will strongly influence plant species composition and abundance.

Heavy-metal concentrations in small mammals from a diffusely polluted floodplain: importance of species- and location-specific characteristics

The soil of several floodplain areas along large European rivers shows increased levels of heavy metals as a relict from past sedimentation of contaminants. These levels may pose risks of accumulation in food webs and toxicologic effects on flora and fauna. However, for floodplains, data on heavy-metal concentrations in vertebrates are scarce. Moreover, these environments are characterised by periodical flooding cycles influencing ecologic processes and patterns. To investigate whether the suggested differences in accumulation risks for insectivores and carnivores, omnivores, and herbivores are reflected in the actual heavy-metal concentrations in the species, we measured the current levels of Zn, Cu, Pb, and Cd in 199 specimens of 7 small mammal species (voles, mice, and shrews) and in their habitats in a diffusely polluted floodplain. The highest metal concentrations were found in the insectivorous and carnivorous shrew, Sorex araneus. Significant differences between the other shrew species, Crocidura russula, and the vole and mouse species was only found for Cd. The Cu concentration in Clethrionomys glareolus, however, was significantly higher than in several other vole and mouse species. To explain the metal concentrations found in the specimens, we related them to environmental variables at the trapping locations and to certain characteristics of the mammals. Variables taken into account were soil total and CaCl(2)-extractable metal concentrations at the trapping locations; whether locations were flooded or nonflooded; the trapping season; and the life stage; sex; and fresh weight of the specimens. Correlations between body and soil concentrations and location or specimen characteristics were weak. Therefore; we assumed that exposure of small mammals to heavy-metal contamination in floodplains is significantly influenced by exposure time, which is age related, as well as by dispersal and changes in foraging and feeding patterns under influence of periodic flooding.