Imperial College London
Alternate

Professor Guy Woodward - Deputy Head of Department

Faculty of Natural Sciences, Department of Life Sciences (Silwood Park)

Professor of Ecology
 
 
 
//

Contact

 

guy.woodward

 
 
//

Location

 

MunroSilwood Park

//

Summary

 

Publications

Citation

BibTex format

@article{Aspin:2019:10.1111/gcb.14495,
author = {Aspin, TWH and Khamis, K and Matthews, TJ and Milner, AM and O'Callaghan, MJ and Trimmer, M and Woodward, G and Ledger, ME},
doi = {10.1111/gcb.14495},
journal = {Global Change Biology},
pages = {230--244},
title = {Extreme drought pushes stream invertebrate communities over functional thresholds},
url = {http://dx.doi.org/10.1111/gcb.14495},
volume = {25},
year = {2019}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Functional traits are increasingly being used to predict extinction risks and range shifts under longterm climate change scenarios, but have rarely been used to study vulnerability to extreme climatic events, such as supraseasonal droughts. In streams, drought intensification can cross thresholds of habitat loss, where marginal changes in environmental conditions trigger disproportionate biotic responses. However, these thresholds have been studied only from a structural perspective, and the existence of functional nonlinearity remains unknown. We explored trends in invertebrate community functional traits along a gradient of drought intensity, simulated over 18 months, using mesocosms analogous to lowland headwater streams. We modelled the responses of 16 traits based on a priori predictions of trait filtering by drought, and also examined the responses of trait profile groups (TPGs) identified via hierarchical cluster analysis. As responses to drought intensification were both linear and nonlinear, generalized additive models (GAMs) were chosen to model response curves, with the slopes of fitted splines used to detect functional thresholds during drought. Drought triggered significant responses in 12 (75%) of the a prioriselected traits. Behavioural traits describing movement (dispersal, locomotion) and diet were sensitive to moderateintensity drought, as channels fragmented into isolated pools. By comparison, morphological and physiological traits showed little response until surface water was lost, at which point we observed sudden shifts in body size, respiration mode and thermal tolerance. Responses varied widely among TPGs, ranging from population collapses of nonaerial dispersers as channels fragmented to irruptions of small, eurythermic dietary generalists upon extreme dewatering. Our study demonstrates for the first time that relatively small changes in drought intensity can trigger disproportionately large functional shifts in stream communities, sugg
AU  - Aspin,TWH
AU  - Khamis,K
AU  - Matthews,TJ
AU  - Milner,AM
AU  - O'Callaghan,MJ
AU  - Trimmer,M
AU  - Woodward,G
AU  - Ledger,ME
DO  - 10.1111/gcb.14495
EP  - 244
PY  - 2019///
SN  - 1354-1013
SP  - 230
TI  - Extreme drought pushes stream invertebrate communities over functional thresholds
T2  - Global Change Biology
UR  - http://dx.doi.org/10.1111/gcb.14495
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000453370700019&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14495
UR  - http://hdl.handle.net/10044/1/87267
VL  - 25
ER  -
Download