Tue, Aug 03, 2021:On Demand
Background/Question/Methods
Global change will alter resources, which are predicted to change the composition and functioning of plant communities. Here, I synthesize plant and ecosystem responses to resource manipulations from the over 100+ global change experiments in herbaceous ecosystems, using the CoRRE (Community Responses to Resource Experiments) database. To study community changes, I study all five ways that community composition can change based on rank-abundance curves. For these analyses, I use datasets with five or more years of community data. As part of this analysis, I study how measures of community composition changes based on Bray-Curtis dissimilarity compare to rank abundance measures of community changes. Finally, to study ecosystem effects, I use a subset of experiment that have above-ground net primary production data for 6 or more years.
Results/Conclusions Overall, I show that plant communities are changing in dynamic ways, with no one best measure to study these changes. Additionally, when I compare using dissimilarity-based measures of composition community change with rank-abundance based measures, I find rank-abundance based measures are more sensitive to detecting community compositional changes. This synthesis of community data demonstrates the need to take a wholistic approach to studying community changes. Finally, when studying how ecosystem production is affected by resource experiments, I find that mean production is frequently affected while the variability of production is not. Overall, I find resource manipulations are changing plant communities which affects ecosystem production.
Results/Conclusions Overall, I show that plant communities are changing in dynamic ways, with no one best measure to study these changes. Additionally, when I compare using dissimilarity-based measures of composition community change with rank-abundance based measures, I find rank-abundance based measures are more sensitive to detecting community compositional changes. This synthesis of community data demonstrates the need to take a wholistic approach to studying community changes. Finally, when studying how ecosystem production is affected by resource experiments, I find that mean production is frequently affected while the variability of production is not. Overall, I find resource manipulations are changing plant communities which affects ecosystem production.