{"type": "FeatureCollection", "features": [{"id": "10.1002/ldr.3656", "type": "Feature", "geometry": null, "properties": {"updated": "2026-05-23T16:14:08Z", "type": "Journal Article", "created": "2020-06-07", "title": "Herbivores stimulate respiration from labile and recalcitrant soil carbon pools in grasslands of Yellowstone National Park", "description": "Abstract

Quantifying the effects of grazing on soil organic carbon (SOC) decomposition is of crucial importance for understanding soil C dynamics. However, less attention has been paid to the pool\uffe2\uff80\uff90specific SOC decomposition and the underlying factors associated with each C pool, representing critical knowledge gaps on soil C dynamics. In this study, we applied a state\uffe2\uff80\uff90of\uffe2\uff80\uff90the\uffe2\uff80\uff90art Bayesian data assimilation technique to re\uffe2\uff80\uff90analyze previous soil incubation data to examine how herbivores influenced the fraction and cumulative respiration of labile and recalcitrant soil C pools from seven edaphically diverse sites in Yellowstone National Park, whereas those variables were not explored in the earlier study. Our results showed that grazing significantly increased cumulative respiration from both labile and recalcitrant C pools. Greater cumulative respiration from the labile C pool was related to grazers increasing labile C pool fractions, while higher cumulative respiration from the recalcitrant C pool was associated with grazers accelerating the decomposition rate of the recalcitrant C pool. Cumulative respiration from both labile and recalcitrant C pools was positively correlated with shoot biomass, soil gravimetric moisture, and soil C and nitrogen content. Our results underscore how knowledge of pool\uffe2\uff80\uff90specific SOC decomposition can provide a better mechanistic understanding of soil C dynamics along topo\uffe2\uff80\uff90edaphic gradients in grazed grassland.Climate warming affects soil carbon (C) dynamics, with possible serious consequences for soil C stocks and atmospheric CO2 concentrations. However, the mechanisms underlying changes in soil C storage are not well understood, hampering long\uffe2\uff80\uff90term predictions of climate C\uffe2\uff80\uff90feedbacks. The activity of the extracellular enzymes ligninase and cellulase can be used to track changes in the predominant C sources of soil microbes and can thus provide mechanistic insights into soil C loss pathways. Here we show, using meta\uffe2\uff80\uff90analysis, that reductions in soil C stocks with warming are associated with increased ratios of ligninase to cellulase activity. Furthermore, whereas long\uffe2\uff80\uff90term (\uffe2\uff89\uffa55\uffc2\uffa0years) warming reduced the soil recalcitrant C pool by 14%, short\uffe2\uff80\uff90term warming had no significant effect. Together, these results suggest that warming stimulates microbial utilization of recalcitrant C pools, possibly exacerbating long\uffe2\uff80\uff90term climate\uffe2\uff80\uff90C feedbacks.Climate warming affects soil carbon (C) dynamics, with possible serious consequences for soil C stocks and atmospheric CO2 concentrations. However, the mechanisms underlying changes in soil C storage are not well understood, hampering long\uffe2\uff80\uff90term predictions of climate C\uffe2\uff80\uff90feedbacks. The activity of the extracellular enzymes ligninase and cellulase can be used to track changes in the predominant C sources of soil microbes and can thus provide mechanistic insights into soil C loss pathways. Here we show, using meta\uffe2\uff80\uff90analysis, that reductions in soil C stocks with warming are associated with increased ratios of ligninase to cellulase activity. Furthermore, whereas long\uffe2\uff80\uff90term (\uffe2\uff89\uffa55\uffc2\uffa0years) warming reduced the soil recalcitrant C pool by 14%, short\uffe2\uff80\uff90term warming had no significant effect. Together, these results suggest that warming stimulates microbial utilization of recalcitrant C pools, possibly exacerbating long\uffe2\uff80\uff90term climate\uffe2\uff80\uff90C feedbacks.Quantifying the effects of grazing on soil organic carbon (SOC) decomposition is of crucial importance for understanding soil C dynamics. However, less attention has been paid to the pool\uffe2\uff80\uff90specific SOC decomposition and the underlying factors associated with each C pool, representing critical knowledge gaps on soil C dynamics. In this study, we applied a state\uffe2\uff80\uff90of\uffe2\uff80\uff90the\uffe2\uff80\uff90art Bayesian data assimilation technique to re\uffe2\uff80\uff90analyze previous soil incubation data to examine how herbivores influenced the fraction and cumulative respiration of labile and recalcitrant soil C pools from seven edaphically diverse sites in Yellowstone National Park, whereas those variables were not explored in the earlier study. Our results showed that grazing significantly increased cumulative respiration from both labile and recalcitrant C pools. Greater cumulative respiration from the labile C pool was related to grazers increasing labile C pool fractions, while higher cumulative respiration from the recalcitrant C pool was associated with grazers accelerating the decomposition rate of the recalcitrant C pool. Cumulative respiration from both labile and recalcitrant C pools was positively correlated with shoot biomass, soil gravimetric moisture, and soil C and nitrogen content. Our results underscore how knowledge of pool\uffe2\uff80\uff90specific SOC decomposition can provide a better mechanistic understanding of soil C dynamics along topo\uffe2\uff80\uff90edaphic gradients in grazed grassland.Climate warming affects soil carbon (C) dynamics, with possible serious consequences for soil C stocks and atmospheric CO2 concentrations. However, the mechanisms underlying changes in soil C storage are not well understood, hampering long\uffe2\uff80\uff90term predictions of climate C\uffe2\uff80\uff90feedbacks. The activity of the extracellular enzymes ligninase and cellulase can be used to track changes in the predominant C sources of soil microbes and can thus provide mechanistic insights into soil C loss pathways. Here we show, using meta\uffe2\uff80\uff90analysis, that reductions in soil C stocks with warming are associated with increased ratios of ligninase to cellulase activity. Furthermore, whereas long\uffe2\uff80\uff90term (\uffe2\uff89\uffa55\uffc2\uffa0years) warming reduced the soil recalcitrant C pool by 14%, short\uffe2\uff80\uff90term warming had no significant effect. Together, these results suggest that warming stimulates microbial utilization of recalcitrant C pools, possibly exacerbating long\uffe2\uff80\uff90term climate\uffe2\uff80\uff90C feedbacks.