Traditionally, ecology, hydrology and stream geomorphology have operated in isolation and development at the interface has been limited. However, it is necessary to combine these natural science fields more efficiently in order to better manage human impacts on aquatic ecosystems.
This kind of multidisciplinary research on natural resources is most effective if social dimensions are also incorporated into it through environmental sociological and environmental economics research. When assessing the success of ecosystem restoration projects, for example, we cannot only state that the ecological and hydrological state of watercourses has improved through restoration, but we also need more knowledge of how successfully ecosystem services have improved through restoration and how to get different user groups to be more committed to restoration.
One of the key factors impacting the natural state of headwater streams in Finland is the sedimentation caused by forest ditch drainage. A number of studies have shown that sedimentation poses an even bigger threat to the biodiversity of headwaters than eutrophication does. In the project, we will first investigate the relative importance of sedimentation as a stress factor in forest streams. The focus will then be on monitoring the impacts of restoration of sediment-stressed streams on hydrological, ecological and socioeconomic response variables. We will carry out socioeconomic studies at the same sites where ecologic-hydrological studies are conducted. This will help us assess whether the restoration projects deemed successful from a natural-science viewpoint are also successful from a socioeconomic viewpoint.
In our research, we will apply two complementary approaches. We will compare hydrological processes and the diversity (particularly zoobenthos, mosses, aquatic mushrooms) and the ecosystem processes (photosynthesis, degradation of organic matter) of natural watercourses in sediment-stressed, restored and natural streams. As it is not possible to control the impact of other factors within the comparative framework, we are testing the possibility of restoring sediment-stressed streams by manipulating different stress factors (sedimentation, weeding, flow variation) in artificial channels through replicated experiments. We also participate in a European project that investigates which of the factors operating at different scales limit restoration success (REFORM Project, 7th Framework Programme).
The ReFFECT project is a joint effort of researchers from the Departments of Biology and Process and Environmental Engineering at the University of Oulu and from the Finnish Environment Institute. The project also involves extensive collaboration with researchers from several EU countries and Canada.