Journal Article

Soil Fungi Respond More Strongly than Fine Roots to Elevated CO₂ in a Model Regenerating Longleaf Pine-Wiregrass Ecosystem

Mitchell, Robert J, Breland, Sabrie, McCormack, M. Luke, Rogers, Hugo H, Runion, G. Brett, Prior, Stephen A, Pritchard, Seth G, Davis, Michael A

2010

Overview

Rising atmospheric CO₂ concentration will affect belowground processes and forest function. However, the direction and magnitude of change for many soil processes are unknown. We used minirhizotrons to observe fine root and fungal dynamics in response to elevated CO₂ in a model regenerating longleaf pine community in open-top chambers. The model community consisted of five plant species common to xeric sandhills longleaf pine stands: Pinus palustris, Quercus margaretta, Aristida stricta, Crotalaria rotundifolia, and Asclepias tuberosa. Elevated CO₂ significantly increased both fine root and mycorrhizal tip standing crop by more than 50% in the deeper soil horizon (17-34 cm). Rhizomorph standing crop was nearly doubled in both deep and shallow soil (P = 0.04). Survivorship results for fine roots and rhizomorphs varied between soil depths. Fine root survivorship was likely influenced more by changes in community composition and species interactions driven by elevated CO₂ rather than by direct effects of elevated CO₂ on the fine roots of individual species. In this system, it appears that elevated CO₂ led to a greater reliance on fungal symbionts to meet additional nutrient requirements rather than substantially increased root growth.

• Publisher: New York : Springer-Verlag,Springer Science+Business Media,Springer-Verlag,Springer,Springer Nature B.V
• Subject: Agricultural soils / Alabama / Animal and plant ecology / Animal, plant and microbial ecology / Aristida stricta / Asclepias tuberosa / Biological and medical sciences / Biomedical and Life Sciences / Carbon dioxide / Community composition / Crotalaria / dry environmental conditions / Ecology / elevated atmospheric gases / elevated CO / Environmental Management / Evergreen trees / fine roots / forest communities / Forest ecosystems / Forest soils / forest stands / Forests / Fundamental and applied biological sciences. Psychology / Fungi / General aspects / Geoecology/Natural Processes / Hydrology/Water Resources / interspecific competition / Life Sciences / longleaf pine / minirhizotron / minirhizotrons / Mortality / mycelium / mycorrhizae / mycorrhizal fungi / Nutrient requirements / open-topped chambers / Pine trees / Pinus palustris / Plant growth / Plant roots / Plant Sciences / Plant species / Quercus acutissima / Quercus margaretta / rhizomorphs / Roots / sandhills longleaf pine communities / Soil depth / Soil fungi / Soil horizons / Soil microorganisms / Synecology / wiregrass / Zoology