Quantification of soil water balance components based on lysimeter measurements

Among other factors, water availability strongly influences the amount and quality of crop yield. International interest in sustainable management of limited freshwater supplies has resulted in increased demand for measurements and modeling methods of cropland water balance components. In order to ensure adequate and sustainable crop production, it is necessary to understand the full water cycle of crop production including evapotranspiration. The purpose of the presented research is to quantify the soil water balance components of arable lands based on an experimental platform that can provide reference data for understanding processes and for model validation. Measurements by large weighing lysimeters are commonly used to test different evapotranspiration estimation methods. The data used for the research is provided by a weighing lysimeter station that was installed in 2018 at Martonvásár in Hungary. The station consists of twelve scientific lysimeters with soil temperature, soil water content, soil water potential sensors installed at several depths in the 2 m deep undisturbed soil profiles, and an ancillary meteorological tower. Every year since 2018 different crop varieties have been grown in six lysimeters. The other six lysimeters are not cultivated and are maintained vegetation-free (bare soil). The measurements are made with high accuracy and fine time resolution (1 reading per minute). Despite our best efforts, several types of errors occurred due to various reasons. The quality assurance and quality control (QA/QC) procedures used in the research help to minimize these errors in processing lysimeter datasets. A web application also contributes to a better interpretation of the data. The poster presents the first results with case studies focusing on wheat evapotranspiration.