Kazuhiko Ohmiya Application of GIS for Investigating Soil Compaction

According to the development of agricultural mechanization, farm work has become efficiently. However, we have been having soil compaction problem by traffics of heavy agricultural tractors and instruments. To improve soil compaction in agricultural fields, subsoiling or deep tillage is effective. But it is hard to decide the time for subsoiling or deep tillage to reduce soil compaction and to evaluate the effect of the work. Because, it is difficult to investigate the soil physical condition at deep area in fields. So we have been trying to investigate soil compaction in fields by the visualization of soil cone resistance. A recording cone penetrometer (Agridry CP-40) with D-GPS (Trimble Pathfinder) and GIS software (ArcView 9.0) were investigated to measure cone resistance and to generate cone resistance distribution map. CP-40 with GPS receiver are not heavy to carry and cone resistance with the coordinates of measuring point is measured by oneself. Only two dimension maps are generated by ArcView, however, these cone resistance distribution maps will be investigated with yield map, soil moisture map, nitrogen map and so on. It is concluded that this system is practical to investigate soil compaction.