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ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Rangeland Resources & Systems Research » Research » Publications at this Location » Publication #340774

Title: Mass ratio effects underlie ecosystem responses to environmental change

item SMITH, MELINDA - Colorado State University
item KOERNER, SALLY - University Of South Florida
item KNAPP, ALAN - Colorado State University
item AVOLIO, MEGHAN - National Socio-Environmental Synthesis Center
item CHAVES, FRANCIS - Colorado State University
item Denton, Elsie
item DIETRICH, JOHN - Colorado State University
item GIBSON, DAVID - Southern Illinois University
item GRAY, JESSE - Colorado State University
item HOFFMAN, AVA - Colorado State University
item Hoover, David
item KOMATSU, KIMBERLY - Smithsonian Environmental Research Center
item SILLETTI, ANDREA - University Of Georgia
item WILCOX, KEVIN - University Of Wyoming
item YU, QIANG - Chinese Academy Of Agricultural Sciences
item BLAIR, JOHN - Kansas State University

Submitted to: Journal of Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/21/2019
Publication Date: 1/15/2020
Publication URL:
Citation: Smith, M., Koerner, S., Knapp, A., Avolio, M., Chaves, F.A., Denton, E.M., Dietrich, J., Gibson, D.J., Gray, J., Hoffman, A.M., Hoover, D.L., Komatsu, K.J., Silletti, A., Wilcox, K., Yu, Q., Blair, J.M. 2020. Mass ratio effects underlie ecosystem responses to environmental change. Journal of Ecology. 108(3):855-864.

Interpretive Summary: The past few decades of research has found that biodiversity loss can have large impacts on ecological function and stability. Much of this research has been biodiversity experiments that remove species randomly, yet there is abundant evidence that non-random species loss is the norm. In this study we compiled data from 23 different experiments that simulated different global change scenarios – from drought, to fire, to changes in nutrients – to see the relative impacts of losing dominant species versus rare species. Contrary to previous work, we found that natural patterns of species loss increased stability by increasing the abundance of the dominant species. These results challenge the notion that biodiversity loss always has a large and negative effect on ecological function and stability.

Technical Abstract: Biodiversity loss can reduce ecosystem function and stability more than other anthropogenic environmental changes. Yet, controversy surrounds the underlying mechanism, because species loss is non-random in natural communities but is simulated randomly in most biodiversity experiments. We compiled data from 23 multi-year experiments that included responses to 11 anthropogenic environmental changes, as well as from non-random biodiversity loss – via either removal of uncommon plant species or the most common (dominant) species. As predicted by the mass ratio hypothesis, loss of a dominant species had large impacts on ecosystem productivity, whereas the loss of uncommon species has small effects. Contrary to other studies, natural (non-random) patterns of species loss increased stability primarily through indirect changes in the abundance and identity of dominant species. These results show that the mass ratio effect rather than species loss per se is the primary determinant of ecosystem function and stability with environmental change.