Abstract

Warming in the Arctic is predicted to change freshwater biodiversity through loss of unique taxa and northward range expansion of lower latitude taxa. Detecting such changes requires establishing circumpolar baselines for diversity, and understanding the primary drivers of diversity. We examined benthic macroinvertebrate diversity using a circumpolar dataset of >1,500 Arctic lake and river sites. Rarefied alpha diversity within catchments was assessed along latitude and temperature gradients. Community composition was assessed through region-scale analysis of beta diversity and its components (nestedness and turnover), and analysis of biotic-abiotic relationships. Rarefied alpha diversity of lakes and rivers declined with increasing latitude, although more strongly across mainland regions than islands. Diversity was strongly related to air temperature, with the lowest diversity in the coldest catchments. Regional dissimilarity was highest when mainland regions were compared with islands, suggesting that connectivity limitations led to the strongest dissimilarity. High contributions of nestedness indicated that island regions contained a subset of the taxa found in mainland regions. High Arctic rivers and lakes were predominately occupied by Chironomidae and Oligochaeta, whereas Ephemeroptera, Plecoptera, and Trichoptera taxa were more abundant at lower latitudes. Community composition was strongly associated with temperature, although geology and precipitation were also important correlates. The strong association with temperature supports the prediction that warming will increase Arctic macroinvertebrate diversity, although low diversity on islands suggests that this increase will be limited by biogeographical constraints. Long-term harmonised monitoring across the circumpolar region is necessary to detect such changes to diversity and inform science-based management.

Keywords

benthic invertebrates; dispersal; diversity; high latitude; lake; river

Published in

Freshwater Biology
2022, Volume: 67, number: 1, pages: 159-175
Publisher: WILEY

SLU Authors

• Goedkoop, Willem

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss
Take urgent action to combat climate change and its impacts


UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.1111/fwb.13805

Permanent link to this page (URI)

https://res.slu.se/id/publ/113505