Title
Species composition but not diversity explains recovery from the 2011 drought in Texas grasslands
Campus Units
Ecology, Evolution and Organismal Biology
Document Type
Article
Publication Version
Published Version
Publication Date
3-2-2017
Journal or Book Title
Ecosphere
Volume
8
Issue
3
First Page
e01704
DOI
10.1002/ecs2.1704
Abstract
Extreme droughts can have profound direct consequences for grassland ecosystems, but it is poorly known how ecosystems recover from drought and what ecological factors are associated with recovery. Recovery occurs when ecosystem functioning returns to values observed prior to a perturbation. Here, we tested for ecosystem recovery after an extreme drought in 2011 in previously established native and exotic experimental communities in Central Texas. Planted mixtures of all native and all exotic species were crossed with a summer irrigation treatment, with eight community compositions (random draws) per treatment. Prior to the drought, native plots had higher diversity than exotic plots, which sets up the prediction that the high-diversity native plots will recover more quickly than exotics. The extreme drought decreased rain-use efficiency ([RUE], annual biomass production per unit of rainfall) by 82%. Rain-use efficiency remained well below pre-drought levels during the growing season after the drought. However, on average, RUE recovered to pre-drought levels by the second growing season following drought. Exotic communities showed higher RUE than native communities, and irrigation significantly reduced RUE in both exotic and native communities across years. Interestingly, not all of the mixtures recovered from the drought, and recovery was associated with species composition, but not diversity. Rain-use efficiency recovery from drought was greatest in native communities in which the proportion of C3 forb biomass increased during and following drought and in exotic communities with a low proportion of short grass biomass. Extreme droughts can exert differential impacts on plant functional groups, leading to a drought legacy effect that reduces recovery with possible long-term repercussions.
Rights
Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.
Language
en
File Format
application/pdf
Recommended Citation
Xu, Xia; Polley, H. Wayne; Hofmockel, Kirsten S.; and Wilsey, Brian J., "Species composition but not diversity explains recovery from the 2011 drought in Texas grasslands" (2017). Ecology, Evolution and Organismal Biology Publications. 244.
https://lib.dr.iastate.edu/eeob_ag_pubs/244
Included in
Atmospheric Sciences Commons, Climate Commons, Plant Biology Commons, Terrestrial and Aquatic Ecology Commons
Comments
This article is published as Xu, Xia, H. Wayne Polley, Kirsten Hofmockel, and Brian J. Wilsey. "Species composition but not diversity explains recovery from the 2011 drought in Texas grasslands." Ecosphere 8, no. 3 (2017). doi: 10.1002/ecs2.1704. Posted with permission.