Format: ORAL

Lydia R. OHalloran1, Justin Robbins1, Thomas OHalloran1

Baruch Institute of Coastal Ecology and Forest Science-Clemson University, Georgetown, South Carolina, USA

Herbaceous-dominated ecosystems are found throughout the world in diverse locations that differ in their climate and edaphic factors. This is reflected in a wide range of annual above- and belowground biomass production, plant diversity and canopy density between these ecosystems. Our study aims to understand how nutrient availability and disturbance impact soil trace gas fluxes and how this relates to plant species relative abundance, diversity, and annual aboveground production. Here, we present data on herbaceous-dominated ecosystems found in coastal South Carolina, USA. This study is part of a global network (DRAGNet) of herbaceous-dominated ecosystem study sites distributed globally using identical protocols for treatment application and data collection. We found the relationship between plant species diversity and aboveground biomass production varies. Aboveground biomass and accumulated litter were not correlated, suggesting that the drivers for carbon assimilation and decomposition are different. The combination of disturbance and nutrient enrichment lead to greater CO2 and CH4 fluxes, while the relationship between N2O and the treatments is less clear. This research will serve as the foundation for future research on how nutrients and soil disturbance interact with the amount of carbon assimilation, and if some species show trait variation in response to these treatments in different regions of the world.