Evaluation of nutrient losses of the furrow dike system during the cultivation of soybean (Glycine max L.) in paddy fields

The furrow dike system plays an important role in maintaining soil moisture and regulating nutrient loads.Reducing runoff and nutrient loads in agricultural lands can improve water use efficiency and reduce environmental impact.This study evaluated nutrient load reduction through the use of furrow dike systems during the cultivation of soybean (Glycine max L.) in paddy fields.The research focused on the effectiveness of furrow dikes in reducing runoff, total nitrogen (TN), and total phosphorus (TP) loads.The experiment was conducted over two years, from 2019 to 2020, with conventional treatment (CT) and furrow dike treatment (FT) plots.The results showed that furrow dikes reduced both runoff and nutrient loads significantly.The furrow dike system reduced runoff by up to 70% and TN loads by 81.8%.Notably, the furrow dike system proved most effective at reducing runoff at daily average rainfall of 10 mm or less and TN loads at 50 mm or less.This study suggests that furrow dikes can effectively mitigate nutrient runoff and improve water use efficiency in paddy fields during soybean cultivation, especially under conditions of low rainfall.