- N. Friberg (1)
- J.H. Janse (1)
- M.H.J.L. Jeuken (1)
- J. Kail (1)
- J.J. Kuiper (1)
- T.F. Moe (1)
- H. Moir (1)
- W.M. Mooij (1)
- M.T. O'Hare (1)
- P.F.M. Verdonschot (1)
- J.T.A. Verhoeven (1)
- M.J. Weijters (1)
- E.P. Westerbeek (1)
- C. Wolter (1)
Effective River Restoration in the 21st Century : From Trial and Error to Novel Evidence-Based Approaches
Friberg, N. ; Angelopoulos, N.V. ; Buijse, A.D. ; Cowx, I.G. ; Kail, J. ; Moe, T.F. ; Moir, H. ; O'Hare, M.T. ; Verdonschot, P.F.M. ; Wolter, C. - \ 2016
Advances in Ecological Research 55 (2016). - ISSN 0065-2504 - p. 535 - 611.
Biodiversity - Catchment - Ecosystem - Hydromorphology - Reform - Water Framework Directive
This paper is a comprehensive and updated overview of river restoration and covers all relevant aspects from drivers of restoration, linkages between hydromorphology and biota, the current restoration paradigm, effects of restorations to future directions and ways forward in the way we conduct river restoration. A large part of this paper is based on the outcomes of the REFORM (REstoring rivers FOR effective catchment Management, http://reformrivers.eu/) project that was funded by EU's 7th Framework Programme (2011-15). REFORM included the most comprehensive comparison, to date, of existing river restorations across Europe and their effect on biota, both in relation to preintervention state and project size in terms of river length restored. The REFORM project outcomes are supplemented by an extensive literature review and two case studies to illustrate key points. We conclude that river restorations conducted up until now have had highly variable effects with, on balance, more positives than negatives. The largest positive effects have interestingly been in terrestrial and semiaquatic organism groups, in widening projects, while positive effects on truly aquatic organisms groups are only seen when in-stream measures are applied. The positive responses of biota are primarily seen as increased abundance of organisms with very little indication that overall biodiversity has increased: specific traits rather than mere species number or total abundance have benefited from restoration interventions. This modest success rate can partly be attributed to the fact that the catchment filter is largely ignored; large-scale pressures related to catchment land use or the lack of source populations for the recolonisation of the restored habitats are inadequately considered. The key reason for this shortfall is a lack of clear objective setting and planning processes. Furthermore, we suggest that there has been a focus on form rather than processes and functioning in river restoration, which has truncated the evolution of geomorphic features and any dynamic interaction with biota. Finally, monitoring of restoration outcomes is still rare and often uses inadequate statistical designs and inappropriate biological methods which hamper our ability to detect change.
GLOBIO-Aquatic, a global model of human impact on the biodiversity of inland aquatic ecosystems
Janse, J.H. ; Kuiper, J.J. ; Weijters, M.J. ; Westerbeek, E.P. ; Jeuken, M.H.J.L. ; Bakkenes, M. ; Alkemade, R. ; Mooij, W.M. ; Verhoeven, J.T.A. - \ 2015
Environmental Science & Policy 48 (2015). - ISSN 1462-9011 - p. 99 - 114.
Catchment - Cyanobacteria - Eutrophication - Hydrological disturbance - Lakes - Land use change - Rivers - Scenario analysis - Wetlands
Biodiversity in freshwater ecosystems - rivers, lakes and wetlands - is undergoing rapid global decline. Major drivers are land use change, eutrophication, hydrological disturbance, climate change, overexploitation and invasive species. We developed a global model for assessing the dominant human impacts on inland aquatic biodiversity. The system consists of a biodiversity model, named GLOBIO-Aquatic, that is embedded in the IMAGE model framework, i.e. linked to models for demography, economy, land use changes, climate change, nutrient emissions, a global hydrological model and a global map of water bodies. The biodiversity model is based on a recompilation of existing data, thereby scaling-up from local/regional case-studies to global trends. We compared species composition in impacted lakes, rivers and wetlands to that in comparable undisturbed systems. We focussed on broad categories of human-induced pressures that are relevant at the global scale. The drivers currently included are catchment land use changes and nutrient loading affecting water quality, and hydrological disturbance and climate change affecting water quantity. The resulting relative mean abundance of original species is used as indicator for biodiversity intactness. For lakes, we used dominance of harmful algal blooms as an additional indicator. The results show that there is a significant negative relation between biodiversity intactness and these stressors in all types of freshwater ecosystems. In heavily used catchments, standing water bodies would lose about 80% of their biodiversity intactness and running waters about 70%, while severe hydrological disturbance would result in losses of about 80% in running waters and more than 50% in floodplain wetlands. As an illustration, an analysis using the OECD 'baseline scenario' shows a considerable decline of the biodiversity intactness in still existing water bodies in 2000, especially in temperate and subtropical regions, and a further decline especially in tropical regions in 2050. Historical loss of wetland areas is not yet included in these results. The model may inform policy makers at the global level in what regions aquatic biodiversity will be affected most and by what causes, and allows for scenario analysis to evaluate policy options.