Development and evaluation of a fertilizer banding opener

Benefits of no-tillage have been widely recognized in reducing soil erosion and improving soil quality. Banding anhydrous ammonia (NH 3) with minimal soil disturbance in no-tillage system can reduce nutrient losses and greenhouse gas emissions. This study focused on developing a low-disturbance and low-cost banding opener for mid row banding NH3 in no-tillage system. The opener was characterized by double or single disks and a simple but effective leaf spring downforce system. Design parameters of the spring downforce system were selected through an optimisation process in which the opener downforce changes were minimised. The optimal design parameters were further validated through a laboratory test.;The prototype of the leaf spring opener was compared with an existing parallel linkage opener in a field condition. The results showed that the two openers had comparable performance, in terms of the cutting depths and uniformity of the cutting depths. Furthermore, the leaf spring had much lower cost. A field experiment was conducted with the opener prototype in banding NH3. The field had clay soil and wheat stubble. The treatments were different opener configurations, including two opener disk configurations (single disk and double disks) and two furrow closing wheel configurations (using furrow closing wheel and without using furrow closing wheel). The field measurements included soil surface disturbance, nitrogen trace, and nitrogen concentrations. Under the given field conditions, the double-disk opener without furrow closing wheel had the best performance with the highest soil nitrogen concentration (80.5 mug/g) and the largest area of NH3/NH 4+ trace zone in soil (4607 mm2). On the contrary, the single-disk opener without furrow closing wheel performed the worst at all aspects, except for the soil surface disturbance.