Fast and furious: Early differences in growth rate drive short‐term plant dominance and exclusion under eutrophication

Ecology and Evolution

Mark Rees¹  Chengjing Chu²  Andy Hector³  Lindsay A. Turnbull³  Pengfei Zhang⁴  Merel B. Soons⁴  George A. Kowalchuk⁴  Yann Hautier⁴  Mariet M. Hefting⁴  Xiaolong Zhou⁵  Guozhen Du⁶  Zhi Guo⁶ 

[1] Department of Animal and Plant Sciences Western Bank University of Sheffield Sheffield UK;Department of Ecology State Key Laboratory of Biocontrol and School of Life Sciences Sun Yat‐sen University Guangzhou China;Department of Plant Sciences University of Oxford Oxford UK;Ecology and Biodiversity Group Department of Biology Utrecht University Utrecht The Netherlands;Institute of Arid Ecology and Environment Xinjiang University Urumqi China;State Key Laboratory of Grassland and Agro‐Ecosystems School of Life Sciences Lanzhou University Lanzhou China;

关键词: competitive dominance;    diversity loss;    early growing season;    Eutrophication;    exclusion;    growth rate;   

DOI  :  10.1002/ece3.6673

来源: DOAJ

【 摘 要 】

Abstract The reduction of plant diversity following eutrophication threatens many ecosystems worldwide. Yet, the mechanisms by which species are lost following nutrient enrichment are still not completely understood, nor are the details of when such mechanisms act during the growing season, which hampers understanding and the development of mitigation strategies. Using a common garden competition experiment, we found that early‐season differences in growth rates among five perennial grass species measured in monoculture predicted short‐term competitive dominance in pairwise combinations and that the proportion of variance explained was particularly greater under a fertilization treatment. We also examined the role of early‐season growth rate in determining the outcome of competition along an experimental nutrient gradient in an alpine meadow. Early differences in growth rate between species predicted short‐term competitive dominance under both ambient and fertilized conditions and competitive exclusion under fertilized conditions. The results of these two studies suggest that plant species growing faster during the early stage of the growing season gain a competitive advantage over species that initially grow more slowly, and that this advantage is magnified under fertilization. This finding is consistent with the theory of asymmetric competition for light in which fast‐growing species can intercept incident light and hence outcompete and exclude slower‐growing (and hence shorter) species. We predict that the current chronic nutrient inputs into many terrestrial ecosystems worldwide will reduce plant diversity and maintain a low biodiversity state by continuously favoring fast‐growing species. Biodiversity management strategies should focus on controlling nutrient inputs and reducing the growth of fast‐growing species early in the season.

【 授权许可】

Unknown