Abstract
<p>Biopores and cracks in soils act as fast transport ways for water and solute, potentially leading to pesticide leaching shortly after application. The biopore module in the agro-hydrological model Daisy was developed to simulate preferential water flow directly to drains, in drain-connecting biopores, and to deeper soil layers, in matrix-terminating biopores.Daisy offers a coherent representation of the soil-plant-atmosphere system, including preferential solute transport, for pesticide fate assessment in agricultural fields. We test the biopore module in Daisy against field measurements of water flow and the behavior of bentazone and imidacloprid after application to a cracking clay field in the Netherlands. We generated two model concepts, DCB with drain-connecting biopores and DCMTB with both drain-connecting and matrix-terminating biopores. Parameters describing the biopores were estimated by inverse modelling to observations of water flow and pesticide concentrations in drains. The results showed that data of water flow and pesticide concentrations in drains contained enough information to parameterize the biopore module in Daisy. Furthermore, both models could simulate the water flow and pesticide leaching to drains well after calibration. Especially, the models were able to describe the high concentration of bentazone in drain water shortly after application. Solute transport in drain-connecting biopores explained the fast break through of pesticides in drains shortly after application. We attributed the discrepancies between observations and simulations in the beginning of the drainage season to the limitations that arise when simulating dynamic preferential flow paths, such as shrinkage cracks, with a static model, such as the biopore model in Daisy. The pesticide distribution in the field over time was represented satisfactorily, especially by the DCMTB-model. We therefore conclude that Daisy can simulate fast break through of pesticides in drain water and describe very well pesticide concentration in drain water throughout the drainage season.</p>
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
