Precision fertilisation techniques are part of precision farming – a way of growing crops that aims to achieve maximum benefits by optimising operations, i.e. adapting agrotechnical measures to the actual needs of the crop and the variability of the field.
The main objective of precision farming is to achieve the most beneficial economic effect, rather than simply maximising yield. Precision fertilisation involves the use of new technologies such as satellite positioning and computer control to apply fertilisers exactly where they are needed, accurately and in the amounts that meet the fertiliser needs of the crop, consistent with the fertiliser plan. Precision farming techniques include assessing local fertiliser needs and controlling how fertiliser is spread and applied using GPS satellite navigation. Fertiliser needs can be determined in a variety of ways: soil quality mapping, identification of uniform zones in the field, mapped soil analyses before the crop is grown, assessment of the nutritional status of the crop during development and growth (‘greenness’ sensors, i.e. chlorophyll or nitrogen content, spectral observations from drones), yield mapping (quantitative and qualitative assessment at harvest) in one year and use of this data in the following crop year based on GPS techniques.
More information: good agricultural practices in farmland fertilisation.
Fertilisation can also be carried out not over the whole field, but in a localised or co-ordinate manner. This is a method used at the time of plant sowing, where nitrogen-phosphorus (starter) fertilisers are placed in such a position that they are best available to the crop but are not taken up by weeds. This technology is becoming increasingly common in the cultivation of wide-ranging crops (maize, oilseed rape, beet, root vegetables, etc.) and also in conjunction with strip-till technology.
More information: precision fertilisation, localised fertilisation.