Estimation of areal evapotranspiration in soybean canopy using the Bowen method



soybean, field experimten, daily evapotranspiration, Bowen-station


Our studies were carried out in the summer of 2020 at the Agrometeorological Research Station of the Georgikon Campus of the Hungarian University of Agriculture and Life Sciences with a Bowen-station deployed in a soybean canopy. The meteorological parameters measured in every 10 min were as follows: within canopy air temperature and humidity, above-canopy air temperature and humidity measured at two levels, and wind speed, as well as soil temperatures measured at several levels. We also completed our measurements with weekly stand height and leaf area measurements (LAI), which are important for the model. Daily evapotranspiration (ET) was calculated from the 10-minute microclimate data. The evapotranspiration modelled with Bowen's ratio in the 2020 measurement season is a state-of-the-art procedure. A Bowenstation provides a relatively inexpensive solution for estimating the spatial evapotranspiration of field crops.


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