University of Oulu

Rolls, R. J., Wolfenden, B., Heino, J., Butler, G. L., & Thiem, J. D. (2023). Scale Rolls, R. J., Wolfenden, B., Heino, J., Butler, G. L., & Thiem, J. D. (2023). Scale dependency in fish beta diversity–hydrology linkages in lowland rivers. Journal of Biogeography, 50, 1692–1709.

Scale dependency in fish beta diversity–hydrology linkages in lowland rivers

Saved in:
Author: Rolls, Robert J.1; Wolfenden, Ben2; Heino, Jani3;
Organizations: 1School of Environmental and Rural Science, University of New England, Armidale, New South Wales, Australia
2School of Environmental Science, Charles Sturt University, Thurgoona, New South Wales, Australia
3Geography Research Unit, University of Oulu, Oulu, Finland
4Department of Primary Industries, Grafton Fisheries Centre, Grafton, New South Wales, Australia
5Department of Primary Industries, Narrandera Fisheries Centre, Narrandera, New South Wales, Australia
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 10.2 MB)
Persistent link:
Language: English
Published: John Wiley & Sons, 2023
Publish Date: 2023-06-13


Aim: A key aspect of biodiversity research is to determine the environmental drivers affecting the degree to which ecological assemblages vary in space (beta diversity). The strength and significance of environmental drivers of beta diversity is, however, influenced by the spatial extent over which beta diversity is assessed. Beta diversity of riverine biota is affected by flow variability. We examined hydrology–beta diversity relationships at two spatial extents (reaches vs. entire systems) within rivers to determine if relationships with hydrological variables are scale dependent or generalisable across spatial scales.

Location: Murray–Darling Basin, Australia.

Taxon: Freshwater fish.

Methods: Fish assemblage data were sourced from two monitoring programmes that sampled sites annually during 2014–2019 and spanned either reaches (<100 km) or the broader ‘system’ extent (>1000 km) of five tributaries. Beta diversity was examined by calculating pairwise (incidence and abundance) dissimilarities for each year to compare temporal trends in beta diversity. Multi-site dissimilarities were modelled against hydrological variables using beta regression.

Results: Inter-annual change in assemblage composition was detected only at the extent of river reaches but not at the extent of river systems. Temporal variation in within-river beta diversity showed inconsistent patterns when compared between the two spatial extents. Within-river beta diversity relationships with hydrological gradients were inconsistent among rivers. Overall, statistical models explained much more variation in within-river beta diversity when assessed at the reach extent when compared to broader river system extents.

Main Conclusions: Our findings highlight that changes in within-river beta diversity are likely to depend on the spatial extent of sampling. Furthermore, inconsistent beta diversity–hydrology relationships among rivers suggest that both empirical evidence and theoretical predictions adopted in ecohydrology may not be transferable among river systems.

see all

Series: Journal of biogeography
ISSN: 0305-0270
ISSN-E: 1365-2699
ISSN-L: 0305-0270
Issue: 10
Pages: 1692 - 1709
DOI: 10.1111/jbi.14672
Type of Publication: A1 Journal article – refereed
Field of Science: 1181 Ecology, evolutionary biology
1172 Environmental sciences
1171 Geosciences
Funding: This work was supported by the New South Wales Environmental Trust (reference: 2018/RD/0051) lead by RJR. JH was supported by grant no. 331957 and no. 332190 from the Academy of Finland.
Academy of Finland Grant Number: 331957
Detailed Information: 331957 (Academy of Finland Funding decision)
332190 (Academy of Finland Funding decision)
Copyright information: © 2023 The Authors. Journal of Biogeography published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.