Projects

The effects of land use changes on biota of running waters

Goals

The main aim of this project is to deepen the knowledge on land use related sedimentation effects on salmonid egg survival and other fitness-related variables. Since lotic macroinvertebrates are the main food of juvenile salmonids, effects of sedimentation on community structure is studied. To improve overall project success we combine both biological and technical knowledge related to this field.

Results

Water protection measures for forest drainage have been shown to work well at the local scale. However, larger scale factors, such as fluctuating discharge, may overwhelm local scale factors (forest drainage) (Louhi et al. 2010).

High sediment loading reduces the rate of development for salmonid intragravel stages (eggs). With slower development, fry have larger yolk sacs at the emergence from gravel into open water. Some studies indicate that slow developing fry face a higher induced risk of predation and are more likely to be swept away by the current, but more in-depth studies are needed.

Impact of research

Results can be applied to in river and watershed restoration projects. Work may result in a new classification of running waters according to degree of sedimention and the restoration work needed.

Takaisin