The Lawrence Berkeley National Laboratory Belowground Biogeochemistry Science Focus Area: Overview and Soil Carbon and Nitrogen Cycling
Authors
Margaret S. Torn* (mstorn@lbl.gov), Peter Nico, Eoin Brodie, Bill J. Riley, Jasquelin Peña, Elaine Pegoraro, Rachel C. Porras, Niklas Blanadet, Jing Tao, Ricardo E. Alves, Kelsey Crutchfield-Peters, Steve Kwatcho Kengdo, Nicola Falco, Baptiste Dafflon, Cynthia Gerlein-Safdi, Kolby Jardine
Institutions
Lawrence Berkeley National Laboratory, Berkeley, CA
URLs
Abstract
In the Lawrence Berkeley National Laboratory Belowground Biogeochemistry Science Focus Area (SFA), researchers study the role of soils in terrestrial biogeochemistry and future climate. The team aims to improve process-level understanding of ecosystem-climate interactions and to develop next-generation predictive capacity suitable for Earth system models. The research is centered around a set of field, laboratory, and model experiments to characterize how biotic and abiotic processes influence soil carbon and nitrogen (N) cycling. Applying experiments and models together is important for exploring how plant-soil-microbe interactions may shape ecosystem responses to a warming climate in the long term. Researchers are conducting two experiments. The Blodgett Forest whole-soil warming (+4ºC) experiment was established in 2013. In 2020, the team doubled the number of experimental plots; heating these new plots started 7 years after the original warming experiment began, allowing researchers to investigate the effect of time explicitly. After 9 full years, heated plots still have carbon dioxide (CO2) respiration, with no detectable effect of warming duration. Future research will explore the relaxation response of microbial respiration and changes in tree belowground functional structure with warming. The Point Reyes grassland whole-soil warming experiment is in the pretreatment monitoring phase; heating will commence winter/spring 2024. In addition to providing a useful contrast to the conifer forest, the grassland experiment heats the whole root zone, allowing researchers to study coupled soil-microbe-plant warming responses, such as plant-soil N interactions and vegetation phenology and productivity. Researchers are also expanding the SFA’s past focus on warming and soil carbon to encompass wildfire as a global change impact and driver, and vegetation dynamics in response. In this poster, the team will share recent highlights on the biogeochemical responses to warming (Task 1 of the SFA). Research on microbiology (Task 2), geochemistry (Task 3) and wildfire (Task 5), and modeling (Task 4) are in posters by Karaoz, Crutchfield-Peters, and Riley respectively.