Performance of constructed fish spawning and rearing channels – development of the Imatra City Brook in Finland

Autor: Jukka Jormola, Antti Haapala, Kirsti Leinonen, Markus Tapaninen, Pekka Vähänäkki, Saija Koljonen
Přispěvatelé: Suomen ympäristökeskus, The Finnish Environment Institute
Rok vydání: 2022
Předmět:
Zdroj: Journal of Ecohydraulics. :1-12
ISSN: 2470-5365
2470-5357
DOI: 10.1080/24705357.2022.2090456
Popis: Freshwater habitats and species have been lost because of river constructions, particularly regarding hydropower plants. Such losses may be mitigated, for example, by providing compensatory habi tats. We present a case which had the objective to promote reproduction of a key species. Imatra City Brook in Finland was constructed in 2014 at a hydropower dam as a new reproduction area for brown trout (Salmo trutta L.). In the planning phase, the objective was to maximize suitable habitat types and areas with limited discharge. Monitoring shows promising densities of brown trout juve niles within only three years, inspiring hope for high smolt production in the main river. The increase in total macroinvertebrate abundances and taxa numbers in the second year of monitoring showed that species richness was comparable to that in natural rivers, and the brook was in a good eco logical state. This case confirms the expected high potential of spawning and rearing channels to improve migratory fish stocks and compensate for lost habitats in constructed rivers.
Databáze: OpenAIRE