Shared drivers but divergent ecological responses: Insights from long-term experiments in mesic savanna grasslands

TitleShared drivers but divergent ecological responses: Insights from long-term experiments in mesic savanna grasslands
Publication TypeJournal Article
Year of Publication2016
AuthorsSmith, MD, Knapp, AK, Collins, SL, Burkepile, DE, Kirkman, KP, Koerner, SE, Thompson, DI, Blair, JM, Burns, CE, Eby, S, Forrestel, EJ, Fynn, RWS, Govender, N, Hagenah, N, Hoover, DL, Wilcox, KR
JournalBioScience
Volume66
Issue8
Pagination666 - 682
Type of ArticleJournal Articles
Accession NumberKNZ001748
KeywordsAboveground net primary productivity, fire, grassland, Grazing, plant community
Abstract

Fire and grazing, key determinants of structure and function of savanna grasslands worldwide, have been extensively altered by humans. We used existing long-term manipulations of fire and grazing in North American and South African mesic savanna grasslands, as well as new experiments, to determine whether the impacts of fire and grazing by large herbivores differed between these systems. We found that despite a body of literature suggesting that these savanna grasslands respond uniquely to fire and grazing, their ecosystem responses (aboveground productivity) were generally similar. In contrast, plant-community responses to fire and herbivores diverged strongly between systems. The differences in plant-community responses, as well as convergence in ecosystem function, were underpinned by a common mechanism: the response of grass dominance to changing fire and grazing regimes. As a result, divergent responses of plant communities to altered fire and grazing regimes did not preclude convergence in ecosystem function.

URLhttps://academic.oup.com/bioscience/article/66/8/666/2464141
DOI10.1093/biosci/biw077
Short TitleBioScience