Linking multi-scale stressors to fish and benthic invertebrates in non-wadable rivers : implications for river management

Knehtl, Miha (author), Urbanič, Gorazd (author)

Understanding how multiple stressors operating across spatial scales shape riverine biota is essential for advancing sustainable ecosystem management. This study evaluated the relative importance of hydromorphological alterations and land-use changes for benthic invertebrate (n = 77) and fish assemblages (n = 92) in large Slovenian rivers. Multivariate analyses were employed to disentangle unique and shared effects of stressors at reach, segment, and catchment scales while accounting for natural variability. The results revealed a hierarchical structuring of stressors, with regional factors shaping local conditions. Fish assemblages were predominantly associated with local-scale stressors, particularly at the segment scale, whereas benthic invertebrates were more strongly associated with shared stressor effects across multiple spatial scales. Stressors explained substantially more variability in fish (43.5%) than in benthic invertebrates (19.9%). Catchment-scale land use showed higher explanatory power than local riparian land use. Typological variables moderately improved model performance, emphasizing the contribution of natural environmental gradients. Our findings suggest that large river management may benefit from a multi-scale perspective that prioritizes segment-scale habitat conditions for fish and coordinated catchment-to-local strategies for benthic invertebrates, with potential benefits for ecosystem resilience and long-term sustainability.

• Language: English
• Keywords: hydromorphology, land-use change, aquatic communities, variance partitioning, habitat integrity, ecological status, biomonitoring, river restoration, scale-dependent responses, ecological assessment
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 23 str.
• Numbering: Vol. 18, iss. 17, art. 8613
• PID: 20.500.12556/RUL-186081
• UDC: 632
• ISSN on article: 2071-1050
• DOI: 10.3390/su18178613
• COBISS.SI-ID: 289002243
• Publication date in RUL: 27.08.2026

Record is a part of a journal

• Title: Sustainability
• Shortened title: Sustainability
• Publisher: MDPI
• ISSN: 2071-1050
• COBISS.SI-ID: 5324897

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: hidromorfologija, sprememba rabe zemljišč, vodne združbe, porazdelitev variance, celovitost habitata, ekološko stanje, biomonitoring, obnova rek

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: V2-24034
• Name: Hidromorfološka tipizacija vodotokov v Sloveniji

• Funder: Republic of Slovenia, Ministry of the Environment and Spatial Planning