2024 AIChE Annual Meeting
(128d) Fungal Contributions to the Birch Effect: Insights from Microfluidics in Dryland Ecosystems
Authors
Guo, Y. S. - Presenter, Oak Ridge National Lab
Weitz, K., Pacific Northwest National Laboratory
Bhattacharjee, A., Pacific Northwest National Laboratory PNNL
Truong, A., Pacific Northwest National Laboratory PNNL
Ryan, A., Pacific Northwest National Laboratory PNNL
Shor, L. M., University of Connecticut
Lipton, M. S., Pacific Northwest National Laboratory
Dryland ecosystems represent a significant biome on Earth, but they are highly susceptible to the impacts of drought and rewetting events that can reduce species diversity and agricultural productivity. With these ecosystems expanding due to climate change, understanding the effects of such events on the soil microbiome is crucial for accurately predicting and mitigating the impact of climate change on ecosystems and carbon cycling. The Birch Effect, arising from drying and rewetting cycles, leads to the efflux of carbon dioxide (CO2) which can be monitored via real-time mass spectrometry (RTMS). While soil fungi play a crucial role in water retention during extended droughts, their specific contribution to CO2 efflux during dry-rewetting cycles and the underlying pore-scale biogeochemistry remains unclear. In this study, we propose an investigation of the Birch Effect using soil micromodels to simulate drought and rewetting cycles. Initially, these micromodels were inoculated with fungi to observe their growth dynamics with and without access to minerals. Subsequently, the micromodels underwent drying to evaluate the impact of dried fungi on moisture retention within soil pores. Following a sufficient drying period, RTMS was employed to quantify CO2 release upon rewetting the micromodels with deionized water. This approach offers insights into the fungal hydraulic lift and the consequent fungal contributions to the Birch Effect, elucidating the critical role of soil fungi in ecosystems.