title: Ectomycorrhizal fungal mycelia turnover in a longleaf pine forest.
abstract: Elucidation of the patterns and controls of carbon (C) flow and nitrogen (N) cycling in forests has been hindered by a poor understanding of ectomycorrhizal fungal mycelia (EFM) dynamics. In this study, EFM standing biomass (based on soil ergosterol concentrations), production (based on ergosterol accrual in ingrowth cores), and turnover rate (the quotient of annual production and average standing biomass estimates) were assessed in a 25-yr-old longleaf pine (Pinus palustris) plantation where C flow was manipulated by foliar scorching and N fertilization for 5 yr before study initiation. In the controls, EFM standing biomass was 30 ± 7 g m(-2) , production was 279 ± 63 g m(-2)  yr(-1) , and turnover rate was 10 ± 3 times yr(-1) . The scorched × fertilized treatment had significantly higher EFM standing biomass (38 ± 8 g m(-2) ), significantly lower production (205 ± 28 g m(-2)  yr(-1) ), and a trend of decreased turnover rate (6 ± 1 times yr(-1) ). The EFM turnover estimates, which are among the first reported for natural systems, indicate that EFM are a dynamic component of ecosystems, and that conventional assessments have probably underestimated the role of EFM in C flow and nutrient cycling.
authors.affiliation: Department of Biology, University of West Georgia, 1601 Maple Street, Carrollton, GA, 30118, USA.
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Hendricks
authors.affiliation: Joseph W. Jones Ecological Research Center at Ichauway, 3988 Jones Center Drive, Newton, GA, 39870, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Mitchell
authors.affiliation: Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive, Hattiesburg, MS, 39406, USA.
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Kuehn
authors.affiliation: Joseph W. Jones Ecological Research Center at Ichauway, 3988 Jones Center Drive, Newton, GA, 39870, USA.
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Pecot
mesh_terms: D018533:Biomass; D065928:Forests; D025282:Mycelium / Q000502:physiology*; D038821:Mycorrhizae / Q000502:physiology*; D028223:Pinus / Q000382:microbiology*; D015203:Reproducibility of Results
keywords: ectomycorrhizal fungal mycelia (EFM); foliar scorching; longleaf pine (Pinus palustris); mortality; nitrogen (N) fertilization; production; standing biomass; turnover