0000000001332060
AUTHOR
Maare Marttila
showing 3 related works from this author
Synthesis of habitat restoration impacts on young-of-the-year salmonids in boreal rivers
2019
River restoration offers the potential to enhance biological integrity, often measured as fish population changes. We used a meta-analytical approach to synthesize density responses to in-stream habitat restoration by young-of-the year (YOY) brown trout and Atlantic salmon in 28 rivers (overall 32 restoration projects) in Finland. We also examined which local and watershed-scale factors most influenced restoration success. Finally, we conducted an expert survey to obtain an independent estimate of a sufficient density enhancement for restoration to be considered successful. Despite strong context-dependency, habitat restoration had an overall positive effect on YOY salmonid density. When co…
Effect of river restoration on life-history strategies in fish communities
2019
Assessments of river restoration outcomes are mostly based on taxonomic identities of species, which may not be optimal because a direct relationship to river functions remains obscure and results are hardly comparable across biogeographic borders. The use of ecological species trait information instead of taxonomic units may help to overcome these challenges. Abundance data for fish communities were gathered from 134 river restoration projects conducted in Switzerland, Germany and Finland, monitored for up to 15 years. These data were related to a dataset of 22 categories of ecological traits describing fish life-history strategies to assess the outcome of the restoration projects. Restora…
In-stream restoration in forestry impacted catchments: benefits to stream habitats, brown trout populations and society
2018
Forestry and wood industry have formed a foundation for Finland’s national economy, yet inevitably at the expense of aquatic environments. From 1940s to 1970s, to provide energy resources for the industry sector, majority of large rivers were dammed for hydropower, blocking off their longitudinal connectivity. Concurrently, majority of the stream channels were dredged to facilitate timber transportation from headwaters to downriver factories. While most large rivers remain blocked, the timber floating ceased in the 1980s, and legislation imposing restoration as well as intensive restoration programs have been established ever since. Habitat restoration has mostly been motivated by the enhan…