Impact of rooting depth and soil hydraulic properties on the transpiration peak of an evergreen forest in northern Thailand in the late dry season

Katsunori Tanaka, Hideki Takizawa, Tomonori Kume, Jianqing Xu, Chatchai Tantasirin, Masakazu Suzuki

Research output: Contribution to journalArticlepeer-review

29 Citations (Scopus)

Abstract

Previous research showed that transpiration in an evergreen broad-leaved forest in northern Thailand (18°48′N, 98°54′E) peaked at the end of the dry season. However, rooting depth limitations on soil water use were not investigated. This study examined the impact of rooting depth and soil hydraulic properties on transpiration using a newly developed soil plant air continuum model. The soil texture at the site was classified as silty sand from the measured relationship between the volumetric soil water content and soil water potential at 0.1-m depths. To effectively simulate heat pulse velocity variation corresponding to dry season transpiration and annual discharge, a rooting depth of 4-5 m was needed, assuming a silty sand soil texture under unsaturated conditions. This value is less than the reported maximum rooting depth of trees and is considered reasonable. A penetration test showed that soil became harder at depths of 4-5 m. The model results suggest that a shallower rooting depth is sufficient to maintain the late dry season transpiration peak if other soil textures with lower hydraulic conductivity are assumed. By contrast, the late dry season transpiration peak could not be maintained under unsaturated conditions if a sandy soil texture with high hydraulic conductivity was assumed, even with a rooting depth of 12 m.

Original languageEnglish
Pages (from-to)1-10
Number of pages10
JournalJournal of Geophysical Research D: Atmospheres
Volume109
Issue number23
DOIs
Publication statusPublished - Dec 16 2004
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Forestry
  • Oceanography
  • Aquatic Science
  • Ecology
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Palaeontology

Fingerprint Dive into the research topics of 'Impact of rooting depth and soil hydraulic properties on the transpiration peak of an evergreen forest in northern Thailand in the late dry season'. Together they form a unique fingerprint.

Cite this