Effects of Chronic Drying on Soil Carbon and Nitrogen Concentrations Across Four Panamanian Rainforests
Category: Research Poster
Author(s): Kelly Kramer, Brittany Bobb, Sophia Barnett, Matthew Sammon
Presenter(s): Kelly Kramer
Mentors(s): Daniela Cusack, Ally Lewis
Ecosystems worldwide are being affected by global climate change. The PARCHED project (PAnama Rainforest CHanges with Experimental Drying) aims to contribute to global research by understanding how long-term (5+ years) of chronic drying affects tropical rainforests. Long-term droughts can indirectly result in lower soil fertility, nutrient availability, and biodiversity. This study investigates how soil carbon and nitrogen levels have responded to chronic drying, interannual variation, and wet-dry season cycles across four distinct lowland tropical forests. The project uses 32 10 x 10 m forest plots, with paired control and rainfall exclusion plots (~70% of rainfall diverted). The forests vary in rainfall and soil fertility. The data presented are for baseline conditions (2018 and 2019) in comparison with year 4 of the experiment (2022). Our analyses to date show that soil carbon has significantly declined with chronic drying in two of the four forests, with no seasonal effect. We are now analyzing the baseline data to determine if there was a pre-existing bias among the plots, or if the apparent soil carbon decline is real. This will ensure the data being used can provide the most accurate predictions for the future. We expect that our preliminary results will provide deeper insights into how chronic drying will affect the tropical ecosystems responsible for significant carbon sequestration globally. This knowledge can be used to inform conservation efforts as climate change continues to affect tropical rainforests and biomes around the globe.