Use of a New Controlled-Loss-Fertilizer to Reduce Nitrogen Losses during Winter Wheat Cultivation in the Danjiangkou Reservoir Area of China

The use of a new controlled-loss-fertilizer (CLF) to reduce nitrogen loss from the Danjiangkou Reservoir of China was explored. Specifically, a three-year experiment was conducted to identify the optimum fertilizer rate for CLF used in wheat production. The treatments included four CLF levels, 20% (20% F), 35% (35% F), 50% (50% F), and 100% (100% F), of the local recommended fertilization dose (LRFD), and traditional fertilizers with the same dose as 50% F as the control (CF). Treatment 50% F with an equivalent fertilizer rate decreased nitrogen (N) runoff loss and leaching loss by 21.6% and 24.5%, while leading to a 9.8% increase in soil residual mineral N when compared to CF. Treatments 50% F and 100% F produced higher wheat yield than the other treatments. At the same fertilizer rate, the grain yield of the 50% F treatment was 5.5% higher than that of CF. Regression analysis of the yield relative to the CLF rate revealed that the optimum CLF rate was about 77% of the LRFD. Overall, the results indicate that CLF with 77% of the LRFD could be the optimum rate for minimizing nitrogen loss and increasing yield and should be considered for wheat production in the area.