Plant Ecology

, Volume 134, Issue 1, pp 77–89

Soil water dynamics and vegetation patterns in a semiarid grassland

  • J. S. Singh
  • D. G. Milchunas
  • W. K. Lauenroth
Article

DOI: 10.1023/A:1009769620488

Cite this article as:
Singh, J.S., Milchunas, D.G. & Lauenroth, W.K. Plant Ecology (1998) 134: 77. doi:10.1023/A:1009769620488

Abstract

Long-term (1985–1992) dynamics and spatial variations in soil water below the evaporative zone were evaluated for a shortgrass steppe with a low and variable precipitation regime. Each of a sandy loam, clay loam, and two sandy clay loam sites comprised a toposequence with upland, midslope and lowland positions. Soil water was monitored at 15 cm intervals providing estimates covering 22.5 to 97.5 cm depths.

Soil water throughout the profile was highest in the clay loam site and lowest in the sandy loam site. However, stored soil water did not vary systematically among slope positions. Total vegetation cover was highest on the lowland in two sites, but was greatest on the midslope position in the other two. Total vegetation cover was greatest on the CL site, which was the wettest in terms of soil water. Soil water depletion was related to the depth-distribution of roots. There was an inverse relationship between aboveground production and soil water content of the 30, 45 and 60 cm layers during the growth period. Root distributions through the profile did not, however, vary with soil texture or with different soil water profiles controlled by texture. The less variable water content of deeper soil layers is a resource which potentially buffers the impact of pronounced variability in precipitation and thus contributes to vegetation stability of the shortgrass community.

CatenaPrecipitationRoot distributionsShortgrass SteppeSoil textureSoil water depletionTopography

Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • J. S. Singh
    • 1
  • D. G. Milchunas
    • 2
  • W. K. Lauenroth
    • 2
  1. 1.Department of BotanyBanaras Hindu UniversityVaranasiIndia
  2. 2.Rangeland Ecosystem Science Department and Natural Resource Ecology LaboratoryColorado State UniversityFt. CollinsUSA