Differences within the plant stand are mainly due to the soil. The use of a ground scanner offers a first impression of these relative differences. EM 38 measurements are the basis of the sub-area related plant production: the influence of the soil can thus be precisely determined for the sub-area related seeding, soil cultivation, fertilising and the variable pest management.
The apparent electric conductivity of the soil is determined using the electromagnetic measurement device EM 38. The inductor transmitter sends a primary electro magnetic AC field into the ground. This induces a weak secondary electromagnetic field, which is registered by the receiver inductor. The apparent electric conductivity is calculated from the relation of the two fields.
The conductivity is recorded as a summed parameter up to a depth of 1.5 m. This is determined by up to 85 % by the fine soil particles (clay content) and up to 15 % by the ion content of the soil water.
Implementation of measurement
The EM 38 is pulled over the field behind a vehicle (a jeep) in the driving lane intervals.During the field crossing, the GPS coordinates and the measured value are directly recorded in digital form - data, which can be further processed in GIS systems. A high measurement density and rapid working enable the best results with a good area performance. The use of the EM 38 is only limited with deeply frozen or freshly cultivated soil.
- Free of disruption and reproducible measurement
- Results are immediately available on site thanks to online methods
- Measurements are carried out free from the subjective influence of people
- High spatial resolution
- Measurements only have to be carried out once
- Measurements can also take place with dry soil conditions
- Information can be gathered independently of deadline