Microbial necromass carbon and nitrogen persistence are decoupled in agricultural grassland soils
Microbial necromass is an important component of soil organic matter, however its persistence and contribution to soil carbon sequestration are poorly quantified. Here, we investigate the interaction of necromass with soil minerals and compare its persistence to that of plant litter in grassland soils under low- and high-management intensity in northwest England. During a 1-year laboratory-based incubation, we find carbon mineralization rates are higher for plant leaf litter than root litter and necromass, but find no significant difference in carbon persistence after 1 year. During a field experiment, approximately two thirds of isotopically-labelled necromass carbon became mineral-associated within 3 days. Mineral-associated carbon declined more rapidly than nitrogen over 8 months, with the persistence of both enhanced under increased management intensity. We suggest that carbon mineralisation rates are decoupled from carbon persistence and that necromass carbon is less persistent than necromass nitrogen, with agricultural management intensity impacting carbon sequestration in grasslands.
© The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. The Version of Scholarly Record of this Article is published in Communications Earth & Environment, 2022, available online at: https://www.nature.com/articles/s43247-022-00439-0 . Keywords: carbon cycle; element cycles; soil microbiology.
Buckeridge, K.M., Mason, K.E., Ostle, N. et al. Microbial necromass carbon and nitrogen persistence are decoupled in agricultural grassland soils. Commun Earth Environ 3, 114 (2022). https://doi.org/10.1038/s43247-022-00439-0