Document


Title

Controls of fine root dynamics across a gradient of gap sizes in a pine woodland
Document Type: Journal Article
Author(s): R. H. Jones; R. J. Mitchell; G. N. Stevens; Stephen D. Pecot
Publication Year: 2003

Cataloging Information

Keyword(s):
  • age classes
  • Aristida beyrichiana
  • biomass
  • burning intervals
  • carrying capacity
  • community ecology
  • competition
  • disturbance
  • ecosystem dynamics
  • fire dependent species
  • forest management
  • Georgia
  • herbaceous vegetation
  • Jones Ecological Research Center
  • lightning
  • logging
  • longleaf pine
  • microclimate
  • moisture
  • mortality
  • mosaic
  • nutrient cycling
  • openings
  • overstory
  • partial cutting
  • pine forests
  • Pinus palustris
  • plant growth
  • precipitation
  • Quercus
  • roots
  • season of fire
  • seedlings
  • site treatments
  • soil moisture
  • soil temperature
  • sprouting
  • statistical analysis
  • temperature
  • understory vegetation
  • vegetation surveys
  • windthrows
Region(s):
Record Maintained By:
Record Last Modified: June 1, 2018
FRAMES Record Number: 40839
Tall Timbers Record Number: 15631
TTRS Location Status: In-file
TTRS Call Number: Fire File
TTRS Abstract Status: Okay, Fair use, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.

Description

Controls of fine dynamics were investigated in a Pinus palustris Mill. (longleaf pine) woodland subjected to two understory vegetation treatments (control versus removed) and four overstory treatments (no gap control, and canopy gaps of three sizes with constant total gap area per stand). Fine root (<2 mm diameter) dynamics were measured over 11 months using ingrowth cores (all treatments) and minirhizotrons (understory removed in no gap control and large gap treatments only). At the fine (microsite) spatial scale, pine and non-pine root mass production responded negatively to each other (P=0.033). Each life form was significantly (P0.028) related to nearby overstory density, and pine root production compensated for reductions in non-pine roots if understory vegetation was removed. Soil moisture and NO3 mineralization rate were negatively related to pine root mass production (ingrowth cores; P<0.00l and P=0.052) and positively related to pine root length production, mortality and turnover (minirhizotrons; P from <0.001 to 0.078). Temperature variance was negatively related to pine root lifespan P<0.00l and positively related to pine root turnover (P=0.003). At the ecosystem scale, pattern of overstory disturbance (gap size and number) had no significant effect on non-pine, pine, or total root production. However, the presence of gaps (versus the no-gap control) increased non-pine root mass production (ANOVA, P=0.055) in natural understory conditions, and reduced pine root mass production (P=O.035) where the understory was removed. Ecosystem-wide pine root length production, mortality and turnover were positively related to weekly soil temperature (P0.02). In natural systems, fine root dynamics are highly variable and strongly affected by biotic factors. Roots quickly close belowground gaps because one life form (pine or non-pine) compensates for the absence of the other. When understory vegetation is removed, however, pine roots respond to the local abiotic environment, particularly moisture and NO3. © Springer-Verlag.

Citation:
Jones, R. H., R. J. Mitchell, G. N. Stevens, and S. D. Pecot. 2003. Controls of fine root dynamics across a gradient of gap sizes in a pine woodland. Oecologia, v. 134, no. 1, p. 132-143.