Abstract
BackgroundUnderstanding the underlying factors that determine the relative abundance of plant species is critical to predict both biodiversity and ecosystem function. Biotic and abiotic factors can shape the distribution and the relative abundance of species across natural communities, greatly influencing local biodiversity.MethodsUsing a combination of an observational study and a five-year plant removal experiment we: (1) documented how plant diversity and composition of montane meadow assemblages vary along a plant dominance gradient using an observational study; (2) tracked above- and belowground functional traits of co-dominant plant species Potentilla and Festuca along a plant dominance gradient in an observational study; (3) determined whether plant species diversity and composition was directly influenced by commonly occurring species Potentilla and Festuca with the use of a randomized plot design, 5-year plant removal experiment (no removal control, Potentilla removed, Festuca removed, n = 10).ResultsWe found that subordinate species diversity and compositional dissimilarity were greatest in Potentilla and Festuca co-dominated sites, where neither Potentilla nor Festuca dominated, rather than at sites where either species became dominant. Further, while above- and belowground plant functional traits varied along a dominance gradient, they did so in a way that inconsistently predicted plant species relative abundance. Also, neither variation in plant functional traits of Festuca and Potentilla nor variation in resources and conditions (such as soil nitrogen and temperature) explained our subordinate diversity patterns. Finally, neither Potentilla nor Festuca influenced subordinate diversity or composition when we directly tested for their impacts in a plant removal experiment.DiscussionTaken together, patterns of subordinate diversity and composition were likely driven by abiotic factors rather than biotic interactions. As a result, the role of abiotic factors influencing local-level species interactions can be just as important as biotic interactions themselves in structuring plant communities.
Highlights
Linkages between species’ relative abundance and ecosystem function are important to predict ecosystem resistance and resilience to global change pressures
We investigated how subordinate species diversity and composition varied along a plant dominance gradient and we directly tested the effects of two co-occurring dominant montane meadow plant species: Festuca thurberi and Potentilla graciilis on community
We asked the following research questions: (1) does diversity and composition of subordinate montane meadow plant assemblages vary across and within a Festuca-Potentilla dominance gradient?; (2) do resources and conditions differ across and within a Festuca-Potentilla dominance gradient?; (3) do above- and belowground functional traits differ in Festuca and Potentilla across the dominance gradient to explain differences in subordinate diversity and composition?
Summary
Linkages between species’ relative abundance and ecosystem function are important to predict ecosystem resistance and resilience to global change pressures. The results of a mesocosm experiment (Kardol et al, 2010) and a field experiment in mountain grassland (Mariotte et al, 2013a) demonstrated that subordinate species can produce relatively more biomass in changed environmental conditions, such as a drought, promoting community stability in a time of disturbance. This suggests that dominant species can respond strongly to the direct presence of an abiotic factor, while subordinate species can be more resistant to abiotic influences and take advantage of the reduced competition (Mariotte et al, 2013a). The role of abiotic factors influencing local-level species interactions can be just as important as biotic interactions themselves in structuring plant communities
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
