U.S. Department of Energy

Pacific Northwest National Laboratory

Soil properties explain diversity of moisture-driven microbial respiration response

Comparisons of the derived moisture function (fp) with empirical moisture functions used in Earth system models.

Linking microscale processes and macroscale fluxes using soil properties in a process-rich simulation.

The Science

Researchers coupled fundamental soil properties with microbial physiology in a pore-scale simulation to predict how microbial respiration will vary under different moisture conditions.

The Impact

By modeling soil microbial respiration response to moisture using a more fundamental understanding of the system, we can improve our predictions of how different soils will respond biogeochemically to drought and inundation events like floods and extreme weather.

Summary

Researchers have observed for a long time a “sweet spot” where soils respire the most carbon dioxide when they aren’t too wet or too dry. However, the location of this zone seemed to vary across different soil types and it was difficult to predict. 

In this study, scientists captured the underlying physical controls and microbial physiology in a computer simulation and generated a range of different respiration-moisture curves across different soil types. This demonstrated the distribution of these different moisture responses across soils and how those differences can be explained by specific soil properties. The findings will help us develop better models for soil biogeochemistry.

Citation

Z. Yan, B. Bond-Lamberty, K. Todd-Brown, V. Bailey, S. Li, C. Liu, C Liu, “A moisture function of soil heterorophic respiration incorporating microscale processes.” Nature Communications volume 9, Article number: 2562 (2018)

Date: 
July 2018
| Pacific Northwest National Laboratory