Brown, LE, Milner, AM and Milner, AM (2012) Rapid loss of glacial ice reveals stream community assembly processes. Global Change Biology, 18 (7). 2195 - 2204. ISSN 1354-1013
Abstract
Glacial retreat creates new habitat which is colonized and developed by plants and animals during the process of primary succession. While there has been much debate about the relative role of deterministic and stochastic processes during terrestrial succession, evidence from freshwater ecosystems remains minimal and a general consensus is lacking. Using a unique 27 years record of community assembly following glacial recession in southeast Alaska, we demonstrate significant change in the trait composition of stream invertebrate communities as catchment glacial cover decreased from ∼70% to zero. Functional diversity increased significantly as glacier cover decreased and taxonomic richness increased. Null modelling approaches led to a key finding that niche filtering processes were dominant when glacial cover was extensive, reflecting water temperature and dispersal constraints. Thereafter the community shifted towards co-occurrence of stochastic and deterministic assembly processes. A further novel discovery was that intrinsic functional redundancy developed throughout the study, particularly because new colonizers possessed similar traits to taxa already present. Rapid glacial retreat is occurring in Arctic and alpine environments worldwide and the assembly processes observed in this study provide new fundamental insights into how glacially influenced stream ecosystems will respond. The findings support tolerance as a key primary successional mechanism in this system, and have broader value for developing our understanding of how biological communities in river ecosystems assemble or restructure in response to environmental change.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | (c) 2012, Blackwell Publishing. Gold Open Access paper. |
Keywords: | Assembly; Deterministic; Glacier Bay; Macroinvertebrate; Niche filtering; River; Stochastic; Traits |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Geography (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 02 Aug 2013 09:55 |
Last Modified: | 15 Sep 2014 03:13 |
Published Version: | http://dx.doi.org/10.1111/j.1365-2486.2012.02675.x |
Status: | Published |
Publisher: | Blackwell Publishing |
Identification Number: | 10.1111/j.1365-2486.2012.02675.x |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:76092 |