Microbial-explicit processes and refined perennial plant traits improve modeled ecosystem carbon dynamics

Geoderma, Journal Year: 2024, Volume and Issue: 443, P. 116851 - 116851

Published: March 1, 2024

Globally, soils hold approximately half of ecosystem carbon and can serve as a source or sink depending on climate, vegetation, management, disturbance regimes. Understanding how soil dynamics are influenced by these factors is essential to evaluate proposed natural climate solutions policy regarding net balance. Soil microbes play key role in both fluxes stabilization. However, biogeochemical models often do not specifically address microbial-explicit processes. Here, we incorporated processes into the DayCent model better represent large perennial grasses mechanisms formation We also take advantage recent improvements grass structural complexity life-history traits. Specifically, this study focuses on: 1) plant sub-model that represents phenology more refined chemistry with downstream implications for organic matter (SOM) cycling though litter inputs, 2) live dead microbe pools influence routing physically protected unprotected pools, 3) Michaelis-Menten kinetics rather than first-order decomposition calculations, 4) feedbacks between microbial pools. evaluated performance two SOM sub-models, (MM) (FO), using observations production, respiration, biomass, from long-term bioenergy research plots mid-western United States. The MM represented seasonal FO which consistently overestimated winter respiration. While sub-models were similarly calibrated total, protected, measurements, differed future response most notably Adding will improve predictions balances but data necessary validate change responses pool allocation.

Language: Английский

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Importance of on-farm research for validating process-based models of climate-smart agriculture

Carbon Balance and Management, Journal Year: 2024, Volume and Issue: 19(1)

Published: May 29, 2024

Abstract Climate-smart agriculture can be used to build soil carbon stocks, decrease agricultural greenhouse gas (GHG) emissions, and increase agronomic resilience climate pressures. The US recently declared its commitment include the sector as part of an overall climate-mitigation strategy, with this comes need for robust, scientifically valid tools GHG flux measurements modeling. If is contribute significantly mitigation, practice adoption should incentivized on much land area possible mitigation benefits accurately quantified. Process-based models are parameterized data from a limited number long-term experiments, which may not fully reflect outcomes working farms. Space-for-time substitution, paired studies, monitoring SOC stocks emissions commercial farms using variety climate-smart management systems validate findings experiments provide process-based model improvements. Here, we describe project that worked collaboratively producers in Midwest directly measure organic (SOC) their at field scale. We study, several unexpected challenges encountered, facilitate further on-farm collection creation secure database stock measurements.

Language: Английский

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Microbial Mechanisms of the Priming Effect over 12 Years of Different Amounts of Nitrogen Management

Agronomy, Journal Year: 2023, Volume and Issue: 13(7), P. 1783 - 1783

Published: June 30, 2023

The return of crop residues and application chemical nitrogen (N) can influence the soil organic carbon (SOC) turnover. However, changes in response priming effect (PE) to N management real farming systems are not fully understood. In this research, we launched a 270-day situ experiment three plots (N0, no N; N1, 300 kg hm−2; N2, 360 hm−2) on long-term maize farm order examine microbial mechanisms that trigger PE presence 13C-labeled residues. We found N1 decreased SOC mineralization positive PE, but increased residual C use efficiency comparison with N0 respectively. be explained by nutrient mining theory for stoichiometry decomposition as reflected abundance oligotrophic phyla copiotrophic N2. biomass (MBC), residue-derived MBC, communities’ complexity were N2 due acidification environment, enhanced bacterial complexity. keystone taxa Vicinamibacteraceae Gemmatimonas preferred recalcitrant Acidibacter favored labile N1. fungal Penicillium, Sarocladium, Cladophialophora exhibited wide substrate-use abilities N0, Our research depicts how structures reshaped through emphasizes functions turnover systems.

Language: Английский

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Aligning theoretical and empirical representations of soil carbon-to-nitrogen stoichiometry with process-based terrestrial biogeochemistry models

Soil Biology and Biochemistry, Journal Year: 2023, Volume and Issue: 189, P. 109272 - 109272

Published: Dec. 8, 2023

Language: Английский

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Advances in modelling soil microbial dynamics

Soil Biology and Biochemistry, Journal Year: 2024, Volume and Issue: 197, P. 109535 - 109535

Published: July 14, 2024

Microbial processes mediating the cycling of carbon and nutrients in soils are complex thus difficult to predict with mathematical models. Such complexity arises because biological ecological dynamics interact physical soil shape patterns resource acquisition use, ultimately organic matter stabilization soil. In article collection "Advances Modelling Soil Dynamics" (https://www.sciencedirect.com/special-issue/10DG8MTGCCF), novel approaches tackle these complexities presented. This perspective summarizes their findings by highlighting theoretical advances outstanding challenges modelling microbial constraints.

Language: Английский

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