Microbial soil respiration and its dependency on carbon inputs, soil temperature and moisture

作者：Jorge Curiel Yuste, Dennis Baldocchi, Alexander Gershenson, Allen H. Goldstein, Laurent Misson, Sherman Wong · 发表于：Global Change Biology · 年份：2007 · DOI：10.1111/j.1365-2486.2007.01415.x · 被引用次数：611 · 研究领域：Soil Carbon and Nitrogen Dynamics、Peatlands and Wetlands Ecology、Soil and Water Nutrient Dynamics

Abstract This experiment was designed to study three determinant factors in decomposition patterns of soil organic matter (SOM): temperature, water and carbon (C) inputs. The study combined field measurements with soil lab incubations and ends with a modelling framework based on the results obtained. Soil respiration was periodically measured at an oak savanna woodland and a ponderosa pine plantation. Intact soils cores were collected at both ecosystems, including soils with most labile C burnt off, soils with some labile C gone and soils with fresh inputs of labile C. Two treatments, dry‐field condition and field capacity, were applied to an incubation that lasted 111 days. Short‐term temperature changes were applied to the soils periodically to quantify temperature responses. This was done to prevent confounding results associated with different pools of C that would result by exposing treatments chronically to different temperature regimes. This paper discusses the role of the above‐defined environmental factors on the variability of soil C dynamics. At the seasonal scale, temperature and water were, respectively, the main limiting factors controlling soil CO2 efflux for the ponderosa pine and the oak savanna ecosystems. Spatial and seasonal variations in plant activity (root respiration and exudates production) exerted a strong influence over the seasonal and spatial variation of soil metabolic activity. Mean residence times of bulk SOM were significantly lower at the Nit...