Climate and land‐use driven reorganisation of structure and function in river macroinvertebrate communities

Fabien Leprieur,Piet Verburg,Jonathan D Tonkin,Mathieu Floury,Théophile L Mouton,Fabrice Stephenson

doi:10.1111/ecog.06148

Abstract

Understanding temporal changes in the composition of species communities over spatial and temporal scales relevant to conservation management is crucial for preventing further biodiversity declines. Here, we assessed patterns and potential drivers of taxonomic and functional temporal β diversity over 26 years (1991–2016) of 64 river macroinvertebrate communities, and the length of New Zealand (37°00'N, 46°00'S). We further examined changes in population size and range shifts of species pools, and related these to taxonomy and functional traits. We found increasing climate and land‐use driven differences in both the taxonomic and functional composition of communities over time, coupled with poleward species colonisations and increasing extirpations in northern locations. Increases in population and species range size were more prevalent than decreases in population and range size. Species shifted their ranges towards higher latitudes on average by 50 km per decade. Despite little to no relationship with taxonomy, we uncovered distinct relationships between functional traits and population trends and latitudinal species range shifts. Species with a high number of reproductive cycles per year and long‐life duration of adults tended to increase their population size, while larger size species with a high number of descendants per reproductive cycle tended to shift their range towards more southern latitudes. Our results suggest that the intensity of disturbances, the geographic location of individuals and communities, and species ecological and functional characteristics, are major determinants of riverine biodiversity reorganisation in the Anthropocene.

Highlights

Current rates of biodiversity change correlate with recent human-induced climate change and land-use activities (IPCC 2014, Brondizio et al 2019)
We described each macroinvertebrate taxon (n = 113) using sixteen functional traits related to morphology, lifehistory, dispersal strategies and resource acquisition methods extracted from the New Zealand freshwater macroinvertebrate trait database (NIWA, )
We found that population trends were taxonomically structured, no relationship was found with species range shifts

Summary

Introduction

Current rates of biodiversity change correlate with recent human-induced climate change and land-use activities (IPCC 2014, Brondizio et al 2019) These biodiversity changes are predicted to increase as human activities intensify (Urban 2015, Johnson et al 2017), reflecting local extirpations and/or colonisations of species and populations across landscapes (Tilman et al 1994, Maclean and Wilson 2011, Brondizio et al 2019). The responses of species likely vary in magnitude among regions of the world and across latitudes (Heino et al 2009, Lenoir et al 2019). There is an imperative need for biodiversity time-series studies over wide and understudied geographical regions to inform conservation planning and policy (Olden et al 2018, Magurran et al 2019)

Methods

Results

Discussion

Conclusion