Plants Mediate the Sensitivity of Soil Respiration to Rainfall Variability |
| |
Authors: | Zachary T Aanderud Jr" target="_blank">Donald R SchoolmasterJr Jay T Lennon |
| |
Institution: | (1) W. K. Kellogg Biological Station, Michigan State University, 3700 East Gull Lake Drive, Hickory Corners, Michigan 49060, USA;(2) Present address: Department of Plant and Wildlife Sciences, Brigham Young University, 489 WIDB, Provo, Utah, 84602, USA;(3) Department of Microbiology and Molecular Genetics, Michigan State University, Hickory Corners, Michigan 49060, USA; |
| |
Abstract: | Soil respiration from grasslands plays a critical role in determining carbon dioxide (CO2) feedbacks between soils and the atmosphere. In these often mesic systems, soil moisture and temperature tend to co-regulate
soil respiration. Increasing variance of rainfall patterns may alter aboveground–belowground interactions and have important
implications for the sensitivity of soil respiration to fluctuations in moisture and temperature. We conducted a set of field
experiments to evaluate the independent and interactive effects of rainfall variability and plant–soil processes on respiration
dynamics. Plant removal had strong effects on grassland soils, which included altered CO2 flux owing to absence of root respiration; increased soil moisture and temperature; and reduced availability of dissolved
organic carbon (DOC) for heterotrophic respiration by microorganisms. These plant-mediated effects interacted with our rainfall
variability treatments to determine the sensitivity of soil respiration to both moisture and temperature. Using time-series
multiple regression, we found that plants dampened the sensitivity of respiration to moisture under high variability rainfall
treatments, which may reflect the relative stability of root contributions to total soil respiration. In contrast, plants
increased the sensitivity of respiration to temperature under low variability rainfall treatment suggesting that the environmental
controls on soil CO2 dynamics in mesic habitats may be context dependent. Our results provide insight into the aboveground–belowground mechanisms
controlling respiration in grasslands under variable rainfall regimes, which may be important for predicting CO2 dynamics under current and future climate scenarios. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|