Net ecosystem exchange, evapotranspiration and canopy conductance in a riparian forest
| Autor: | John Kochendorfer, Edward Haas, Walter C. Oechel, Kyaw Tha Paw U, Eugenia González del Castillo |
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| Rok vydání: | 2011 |
| Předmět: |
Hydrology
Atmospheric Science Global and Planetary Change geography geography.geographical_feature_category biology Eddy covariance Biometeorology Forestry biology.organism_classification Canopy conductance Populus fremontii Evapotranspiration Riparian forest Environmental science Agronomy and Crop Science Groundwater Riparian zone |
| Zdroj: | Agricultural and Forest Meteorology. 151:544-553 |
| ISSN: | 0168-1923 |
| DOI: | 10.1016/j.agrformet.2010.12.012 |
| Popis: | The ecosystem fluxes of mass and energy were quantified for a riparian cottonwood (Populus fremontii S. Watson) stand, and the daily and seasonal courses of evapotranspiration, CO2 flux, and canopy conductance were described, using eddy covariance. The ecosystem-level evapotranspiration results are consistent with those of other riparian studies; high vapor pressure deficit and increased groundwater depth resulted in reduced canopy conductance, and the annual cumulative evapotranspiration of 1095 mm was more than double the magnitude of precipitation. In addition, the cottonwood forest was a strong sink of CO2, absorbing 310 g C m−2 from the atmosphere in the first 365 days of the study. On weekly to annual time scales, hydrology was strongly linked with the net atmosphere–ecosystem exchange of CO2, with ecosystem productivity greatest when groundwater depth was ∼2 m below the ground surface. Increases in groundwater depth beyond the depth of 2 m corresponded with decreased CO2 uptake and evapotranspiration. Saturated soils caused by flooding and shallow groundwater depths also resulted in reduced ecosystem fluxes of CO2 and water. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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