Influence of Longitudinal Fragmentation on Length–Weight Relationships of Fishes in the Someșul Cald River, Romania
Paul Uiuiu,
Radu Constantinescu,
Tudor Păpuc,
George-Cătălin Muntean,
Maria Cătălina Matei-Lațiu,
Anca Becze,
Daniel Cocan,
Călin Lațiu,
Cristian Olimpiu Martonoș
Affiliations
Paul Uiuiu
Department of Fundamental Sciences, Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Mănăştur Street, RO-400372 Cluj-Napoca, Romania
Radu Constantinescu
Department of Fundamental Sciences, Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Mănăştur Street, RO-400372 Cluj-Napoca, Romania
Tudor Păpuc
Department of Fundamental Sciences, Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Mănăştur Street, RO-400372 Cluj-Napoca, Romania
George-Cătălin Muntean
Department of Fundamental Sciences, Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Mănăştur Street, RO-400372 Cluj-Napoca, Romania
Maria Cătălina Matei-Lațiu
Department of Animal Physiology, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Mănăștur Street, RO-400372 Cluj-Napoca, Romania
Anca Becze
National Institute for Research and Development of Optoelectronics INOE 2000, Research Institute for Analytical Instrumentation, 67 Donath Str., RO-400293 Cluj-Napoca, Romania
Daniel Cocan
Department of Fundamental Sciences, Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Mănăştur Street, RO-400372 Cluj-Napoca, Romania
Călin Lațiu
Department of Fundamental Sciences, Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Mănăştur Street, RO-400372 Cluj-Napoca, Romania
Cristian Olimpiu Martonoș
Department of Biomedical Sciences, Ross University School of Veterinary Medicine, Basseterre P.O. Box 334, Saint Kitts and Nevis
Romania has a rich hydrographic network, which permitted the construction of over 80 large dams on its water courses, estimating a number between 545 and 674 hydropower plants that were either built or were in a different construction stage on the rivers of Romania in 2021. These hydropower plants were often built outside specific legislation regarding ecological impacts, especially before 1990. Longitudinal fragmentation of rivers causes severe ecological impacts on biodiversity, food chains, and nutrient cycles. Someșul Cald River is the main tributary of Someșul Mic River, the most important water source for the northwestern region of Transylvania. On its course, several dams and reservoirs were built from 1968 to 1980 for electricity production and population freshwater supply. The present study aimed to analyze the length–weight relationships (LWRs) and condition factors occurring in the longitudinally fragmented Someșul Cald River. The LWRs, relative condition factor Kn, and Fulton condition factor K were determined based on total length and wet body weight. Comparisons of LWRs, Kn, and K across river sections constrained by dams showed that some fish species exhibited similar growth patterns and physiological conditions, while others differed significantly. Freshwater fish physiology is altered by longitudinal fragmentation, both natural and artificial. Barriers such as dams influence the energy gradient, limiting feed availability and, consequently, the life history of fish species. Long-term management plans regarding conservation should take into consideration existing fish species population dynamics, along with their physiological and somatic status.
