The Variable-Rate Decision for Multiple Inputs with Multiple Management Zones

determining whether VRT or URT should be used on a particular field because each field
presents a different case. Nevertheless, for the case presented in this paper, a wide range of
spatial variability would provide increased net returns for VRT application of nitrogen and water
relative to URT application.

To utilize this methodology, farmers need knowledge of the field-specific management
zones for a particular crop and inputs, including the parameters of the corresponding yield
response functions. Unfortunately, this knowledge is difficult to obtain with certainty, but
farmers are currently using other precision farming technologies (eg., yield monitors, grid soil
sampling, field mapping) that can be used to identify management zones and their yield response
potentials (English, Roberts, and Sleigh). Even when information about the management zones
and yield response functions is not known, these methods can be used to obtain rough estimates
about whether investment in obtaining additional spatial information to more precisely identify
management zones and estimate their corresponding yield response functions is potentially
worthwhile.

11

<<   9   10   11   12   13   14   15   >>

More intriguing information