Precision agriculture is about efficient utilization of resources adapted to local conditions in growing fields. With modern technology, one can at a geographical level of precision collect and coordinate detailed information on environmental factors and nutritional status. This information makes it possible for farmers to make informed decisions, which saves resources and reduces nutrient leaching. Precision agriculture is a major part of future farming as we must feed a growing world population in a sustainable way. It also opens opportunities for greater automation of agricultural work.

World agriculture uses nearly 200 million tons annually of artificial fertilizers, where phosphorus is an important element. Phosphorus is very common in the earth’s crust, but the recovery, as it looks today, is primarily through mining in phosphate mines. This means that agriculture at present is dependent on the availability of phosphate ore, a finite resource. Many analysts believe that mineable phosphate reserves in the future will become a scarce commodity and a limiting factor for agriculture. Meanwhile, food production must increase in the future through higher yields from existing land.

World agriculture uses 200 million tonnes of fertilizer per year, but it is done on a finite resource: phosphate ore.

Conserving fertilizer and using it where it is most needed is therefore essential – especially since, in practice, it is often over used and causes eutrophication of rivers and seas. Similarly, it is obviously desirable not to overuse insecticides, herbicides – and not least water – a natural resource that in many places is an acute shortage.

Adapting to micro conditions

The problem is that the same cultivation area can accommodate a wide range of conditions. This is especially true for modern agriculture, which often consists of large areas. Traditionally, entire growing areas are fertilized in the same way, without taking into account local variations and micro conditions that may occur.

Precision agriculture is a collective term for several techniques and methods – but the common denominator is customizable: interventions tailored to the needs at a certain time in a certain place. Fertilizers, pesticides, irrigation and other measures can be directed to where they are needed, instead of being spread evenly over an entire growing area. The advantage is better and higher yields, less nutrient leaching and a more efficient use of resources.

Geographic Information Systems (GIS)

By collecting data and documenting differences in crops, soil quality and other conditions over time and in the fields parameters can be adapted. The data collection, for example, can come from aerial photography, satellite imagery or sensors. Measured data coupled with a geographic information system GIS means the data can be analyzed and visualized on maps.

Some sensors may be located below the surface at regular distances from each other where they then form a permanently installed network, which continuously measures and reports, wirelessly, physical and chemical data to a central computer. Other types of sensors can be mounted on farm machinery and collect data about the crops they cover. One can, for example, identify a crop’s nutrient requirements by allowing sensors to observe the colour of the plants, and from that regulate the nutrition of that particular site. Other sensors can measure the presence of fungus, or control crop growth rates. Sensors in the soil can measure quantities such as humidity, temperature and light influx.

Continuously capturing aerial and satellite imagery of growing crops can also provide much more information. Remote sensors measure the radiated and reflected light in different wavelengths, and gives an idea of how crops and soils are developing; And through spectral analysis, one can measure variables such as humidity, surface temperature, photosynthetic activity – and even the presence of pests. The result is both a basis to determine where resources are most useful, and for example to make crop forecasts. Combined with hyper-local weather forecasting, the models become even more precise.

Sensor-generated aerial photographs of fields in Arizona show vegetation density, soil moisture and photosynthetic activity (NASA)

Similar analyses can also be done on a large scale, continentally or even globally. One example is the Harvest Choice initiative, which collects data on the growing conditions in Africa and makes available the information on a map as a strategic tool for local agriculture.

Swarms of smart agricultural machinery

Smarter tractors, harvesting and sowing technology is already established in many places, in the form of agricultural machinery equipped with GPS positioning and sensor technology, which use geographical information systems as a basis for adapting measures continuously as they move across the fields.

Compared with traditional machines, they have already become more independent and automated in their work – and robotics is about to gain a footing in mechanized agriculture. In the future, the development could take another big leap, when every big, driver-operated machine is replaced by a number of small autonomous robots that are placed in the fields to jointly perform different tasks. Maybe they are solar powered, small enough to move between planting rows, cheap and easy – but interacting and communicating among themselves and with the GIS.

Prospero, a prototype of such a robot, is capable already of planting. The vision is that it and its followers ultimately master every step of the growing process. A direct benefit of replacing heavy machines with lightweight robots is reduced soil compression and less ground disturbance. This would also mean reducing soil erosion, plowing needs, and improve soil quality by leaving worms and microbes undisturbed.

Greater precision in the use of chemicals benefits the environment, farmers and consumers. It reduces costs for farmers, increasing yields and optimizes the use of resources. There are many promising approaches that are in development, from the very large-scale perspective down to the individual farm, and the future of sustainable agriculture will – no matter what it looks like in general – is certain to build on this new technological opportunity for increased precision and tailored measures.

Learn more about precision agriculture in the article “Satellite-controlled agricultural machinery provides environmental benefits.”

The article was published in December 2013.