Application of Remote Sensing and Gis in Precision Farming

Historically, agronomic practices and management recommendations have been developed for implementation on a field basis. This generally results in the uniform application of tillage, fertilizer, sowing and pest control treatments at a field scale. Farm fields, however, display considerable spatial variation in crop yield, at the 'within-field' scale. Such uniform treatment of a field ignores the natural and induced continuous variation in soil properties, and may result in zones being underor over-treated, giving rise to economic and environmental problems associated with this inefficient use of resource inputs. The more substantial of these problems being: economically significant yield losses, excessive chemical costs, gaseous or percolatory release of chemical components, unacceptable long-term retention of chemical components and a less than optimal crop growing environment.