Abstract
The aim of this study is to quantify the dissolved organic carbon (DOC) of drainage water from paddy fields in agricultural areas of Tottori prefecture, Japan. In four experimental paddy fields, DOC concentration varied much from 1.1 to 10.1 mg C l−1, and was the highest during heavy runoff that occurred in April when there was a non-agricultural period. However, variation in DOC concentration did not always correspond to rainfall, but depended more on cultivation-activity events such as tilling, planting, draining in summer, and final draining in autumn. The water discharge rate from each experimental field was estimated by using a hydrologic model (the Tank Model and a genetic algorithm). Daily DOC export rate per unit area of three experimental paddy fields was calculated to be 0.0074, 0.0052, and 0.0081 kg a−1 day−1, respectively. The daily DOC export rate showed large seasonal variation with the highest value in May and June. It can be concluded that DOC export from paddy fields can be a substantial source of DOC in receiving waters, and the export rate depends much on cultivation method practice. It might be suggested that DOC export from paddy fields can be controlled by a better water management practice of farmers.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.