Plant and Soil

, Volume 294, Issue 1, pp 113–123

Influence of soil thickness on stand characteristics in a Sierra Nevada mixed-conifer forest

  • Marc D. Meyer
  • Malcolm P. North
  • Andrew N. Gray
  • Harold S. J. Zald
Regular Article

DOI: 10.1007/s11104-007-9235-3

Cite this article as:
Meyer, M.D., North, M.P., Gray, A.N. et al. Plant Soil (2007) 294: 113. doi:10.1007/s11104-007-9235-3

Abstract

Soil thickness can be an important factor influencing vegetation, yet few spatially-explicit studies have examined soil horizon thickness and vegetation composition in summer-drought forests. We compared seismic and soil penetration measurements of combined A + C and Cr horizon thickness, soil moisture and temperature, and stand variables in a contiguous 4-ha mixed-conifer stand of the Sierra Nevada. Thickness of A + C and Cr horizons were highly variable but were not correlated to each other. Total basal area and canopy cover were positively related with A + C horizon thickness, and shrub cover was positively related with Cr horizon thickness. Basal area of white fir [Abies concolor (Gord and Glend) Lindl.] and incense-cedar [Calocedrus decurrens (Torrey) Florin] were positively correlated with A + C horizon thickness, but there was no relationship between A + C or Cr horizon thickness and basal area of Jeffrey pine (Pinus jeffreyi Grev. and Balf.), sugar pine (P. lambertiana Douglas), or red fir (A. magnifica A. Murray). Both white and red fir seedlings were associated with decreased soil temperature, but only white fir seedlings were positively associated with soil moisture. Soil penetration estimates of soil thickness were similar to seismic estimates for shallow soils (<50 cm depth) but were poorly related on deeper soils. Visual surface conditions and tile probe estimates of soil thickness can be highly misleading because ‘shallow’ areas may have a thick layer of weathered bedrock that can serve as a potential rooting medium for deep-rooted trees and shrubs. In our study only the refraction seismic method had the potential to measure total soil depth that included A + C and Cr horizon thickness.

Keywords

Forest regenerationRefraction seismic methodSoil moistureSoil temperature

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Marc D. Meyer
    • 1
  • Malcolm P. North
    • 1
    • 2
  • Andrew N. Gray
    • 3
  • Harold S. J. Zald
    • 3
    • 4
  1. 1.Sierra Nevada Research CenterPacific Southwest Research Station, USDA Forest ServiceDavisUSA
  2. 2.Department of Plant SciencesUniversity of CaliforniaDavisUSA
  3. 3.Pacific Northwest Research StationUSDA Forest ServiceCorvallisUSA
  4. 4.Department of Forest ScienceOregon State UniversityCorvallisUSA