Dataset Information

Opposing community assembly patterns for dominant and nondominant plant species in herbaceous ecosystems globally.

ABSTRACT: Biotic and abiotic factors interact with dominant plants-the locally most frequent or with the largest coverage-and nondominant plants differently, partially because dominant plants modify the environment where nondominant plants grow. For instance, if dominant plants compete strongly, they will deplete most resources, forcing nondominant plants into a narrower niche space. Conversely, if dominant plants are constrained by the environment, they might not exhaust available resources but instead may ameliorate environmental stressors that usually limit nondominants. Hence, the nature of interactions among nondominant species could be modified by dominant species. Furthermore, these differences could translate into a disparity in the phylogenetic relatedness among dominants compared to the relatedness among nondominants. By estimating phylogenetic dispersion in 78 grasslands across five continents, we found that dominant species were clustered (e.g., co-dominant grasses), suggesting dominant species are likely organized by environmental filtering, and that nondominant species were either randomly assembled or overdispersed. Traits showed similar trends for those sites (<50%) with sufficient trait data. Furthermore, several lineages scattered in the phylogeny had more nondominant species than expected at random, suggesting that traits common in nondominants are phylogenetically conserved and have evolved multiple times. We also explored environmental drivers of the dominant/nondominant disparity. We found different assembly patterns for dominants and nondominants, consistent with asymmetries in assembly mechanisms. Among the different postulated mechanisms, our results suggest two complementary hypotheses seldom explored: (1) Nondominant species include lineages adapted to thrive in the environment generated by dominant species. (2) Even when dominant species reduce resources to nondominant ones, dominant species could have a stronger positive effect on some nondominants by ameliorating environmental stressors affecting them, than by depleting resources and increasing the environmental stress to those nondominants. These results show that the dominant/nondominant asymmetry has ecological and evolutionary consequences fundamental to understand plant communities.

SUBMITTER: Arnillas CA

PROVIDER: S-EPMC8717298 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Opposing community assembly patterns for dominant and nondominant plant species in herbaceous ecosystems globally.

Arnillas Carlos Alberto CA Borer Elizabeth T ET Seabloom Eric W EW Alberti Juan J Baez Selene S Bakker Jonathan D JD Boughton Elizabeth H EH Buckley Yvonne M YM Bugalho Miguel Nuno MN Donohue Ian I Dwyer John J Firn Jennifer J Gridzak Riley R Hagenah Nicole N Hautier Yann Y Helm Aveliina A Jentsch Anke A Knops Johannes M H JMH Komatsu Kimberly J KJ Laanisto Lauri L Laungani Ramesh R McCulley Rebecca R Moore Joslin L JL Morgan John W JW Peri Pablo Luis PL Power Sally A SA Price Jodi J Sankaran Mahesh M Schamp Brandon B Speziale Karina K Standish Rachel R Virtanen Risto R Cadotte Marc W MW

Ecology and evolution 20211122 24

Biotic and abiotic factors interact with dominant plants-the locally most frequent or with the largest coverage-and nondominant plants differently, partially because dominant plants modify the environment where nondominant plants grow. For instance, if dominant plants compete strongly, they will deplete most resources, forcing nondominant plants into a narrower niche space. Conversely, if dominant plants are constrained by the environment, they might not exhaust available resources but instead m ...[more]

PMID: 35003636

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Dataset Information

Opposing community assembly patterns for dominant and nondominant plant species in herbaceous ecosystems globally.

Publications

Opposing community assembly patterns for dominant and nondominant plant species in herbaceous ecosystems globally.

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