Global synthesis of vegetation control on evapotranspiration partitioning. Issue 19 (1st October 2014)

• Record Type: Journal Article
• Authors: Wang, Lixin; Good, Stephen P.; Caylor, Kelly K.
• Is Part Of: Geophysical research letters. Volume 41:Issue 19(2014:Oct.)
• Page Start: 6753
• Page End: 6757
• Publication Date: 2014-10-01
• Subjects: Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2014GL061439
• Languages: English
• ISSNs: 0094-8276

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Evapotranspiration (<italic>ET</italic>) is an important component of the global hydrological cycle. However, to what extent transpiration ratios (<italic>T/ET</italic>) are controlled by vegetation and the mechanisms of global‐scale <italic>T/ET</italic> variations are not clear. We synthesized all the published papers that measured at least two of the three components (<italic>E</italic>, <italic>T</italic>, and <italic>ET</italic>) and leaf area index (<italic>LAI</italic>) simultaneously. Nonlinear relationships between <italic>T/ET</italic> and <italic>LAI</italic> were identified for both the overall data set and agricultural or natural data subsets. Large variations in <italic>T/ET</italic> occurred across all <italic>LAI</italic> ranges with wider variability at lower <italic>LAI</italic>. For a given <italic>LAI</italic>, higher <italic>T/ET</italic> was observed during later vegetation growing stage within a season. We developed a function relating <italic>T/ET</italic> to the growing stage relative to the timing of peak <italic>LAI</italic>. <italic>LAI</italic> and growing stage collectively explained 43% of the variations in the global <italic>T/ET</italic> data set, providing a new way to interpret and model global <italic>T/ET</italic> variability.</p> </abstract>