Micro-dosing
Fertilizer microdosing refers to the technique of applying a small dose (2-6 g) of NPK-fertilizer into the planting hole together with the seed at the time of planting or next to the seedling immediately after emergence. In comparison to no fertilizer application and its broadcasting, microdosing is reported to increase yield by 70% and 50% respectively. However, so far all reported results about microdosing were obtained from crop monocultures. To fill existing knowledge gaps for microdosing effectiveness under agroforestry conditions, the DecLaRe project (Decision support for strengthening land resilience in the face of global challenges) is co-experimenting with farmers NPK microdosing in an agroforestry system of maize and shea tree (Vitellaria paradoxa) parklands in the Savannah Region of Ghana.
The decision is to assess the farm economic benefit of micro-dosing in a system of maize and shea tree. Considering the status quo this decision comes with 3 alternatives:
- Maize + Shea tree (status quo)
- Maize+ shea tree + Full NPK
- Maize + shea tree + NPK microdosing
Figure 1: A simple Impact pathways of the system
The bright colour on fertilizer in the conceptual model means that the variable will switch on and off depending on which alternative (2 or 3) we consider in the NPV.