EGNOS for yield mapping: The power of knowledge

EGNOS continues to provide fertile ground for successful agricultural applications and companies such as CLAAS Agrosystems are harvesting its potential: according to Mr Klaus-Herbert Rolf, the company's Head of Marketing, about 90% of high-end combine harvesters currently sold by CLAAS are equipped with EGNOS-enabled receivers. Rolf says EGNOS is no longer a technological opportunity, but rather a necessary infrastructure for successful agriculture.

Today, GNSS and EGNOS can be used to increase productivity in all phases of agricultural activity. As farmers prepare the soil, GNSS-based steering systems help them to choose consistent driving strategies and to avoid row overlaps. According to CLAAS, European farmers can save up to 7% on operating costs with EGNOS, thanks to time reduction and reduction of fuel, oil and machine expenses. During seeding activities, agricultural engineers rely on EGNOS to distribute the right seed volume in the right spot. As fertilisers and plant protection products are applied to the crop, it is now possible to adjust nitrogen and crop-spraying activities with a high degree of accuracy, combining GNSS positioning, onboard sensors and application maps. Finally, during the harvest, EGNOS receivers coupled with yield monitors provide accurate spatial coordinates for yield monitoring data, which can be used to create yield maps of each field.

The key role of yield monitoring and yield mapping

Yield monitoring and yield mapping often represent the first activities performed by farmers embracing precision agriculture solutions. The goal of precision agriculture, also known as site-specific farming, is to apply the right inputs, such as seeds, nutrients and fertilisers in the right places and at the right time. The reason behind this is that the same crop can present significant variability within its extension and the application of inputs at a fixed rate results in over-application in some areas and under-application in others. Yield maps provide farmers with the information required to better estimate the needs of crops, allowing them to record a history of field performance and, as a consequence, make better management choices.

The necessary data for the creation of yield maps is typically generated by yield monitoring systems installed in combine harvesters. These systems are generally include four key elements:

  • A mass flow sensor, which monitors the volume of grain moving through the grain elevator of the harvester;
  • A grain moisture sensor, to measure the moisture of the harvested grain. This allows a better estimate of the grain yield, and farmers can assess whether the harvest timing was correct and estimate the cost of grain drying;
  • A GNSS receiver, providing the spatial positioning required to georeference the measurements within the crop.

Once the harvest is complete, the information about the grain mass and moisture is combined with the position on the farmers’ computers and processed through Geographic Information System (GIS) programmes in order to create yield maps. These maps enable farmers to visualise on a coloured map (fig. 1) the performance of the crop. The colours of the map represent different performance ranges, so that farmers can easily distinguish between areas with richer yields and zones performing below the average.

Figure 1 - A representation of yield mapping (CLAAS Agrosystems)

The knowledge of crop characteristics and performance provided by yield maps is used to create application maps, which represent the inputs used by farmers for the application of seeds, nutrients and fertilisers at a variable rate within the same field. As these activities are performed, GNSS systems take advantage of EGNOS accuracy to continuously update the seed application rate according to the seeder's position on the crop.

Moreover, year after year, indications about the crop performance provided by yield mapping help farmers to identify the key sources of yield variability; some may be due to management practices, such as suboptimal soil compaction, water management or mechanical errors. Others may be natural, due to parameters such as soil fertility, pest concentration, weather and crop configuration. With time, yield mapping helps farmers to learn more about the characteristics of their own fields, and the increased accuracy provided by EGNOS allows enhancing the accuracy of the data every time it is gathered.

Blooming benefits, from farms to the wider economy

Precision farming with integrated yield mapping enables farmers to reach higher yields while simultaneously improving environmental standards, as increased operations efficiency is coupled to reduced fuel consumption and optimisation of fertiliser use. At the same time, farmers can reap the benefits of EGNOS beyond the fields. GNSS positioning can be used to monitor, track and analyse the work flow remotely and to provide routing tools for product transport operations. The combination of these advances has revitalised the attractiveness of farming jobs; job performance has increased, and so has the reputation of the agricultural profession, transitioning from tradition to technology.

These changes are dramatically boosting the productivity of European agriculture. Technical progress is of central importance to keeping pace with world population growth: FAO statistics show that the availability of agricultural land worldwide has halved from 1961 to 2000, as the hectares of cultivable land per person have dropped from 0.4 to 0.2 in less than 40 years. This trend is expected to continue, boosted by population growth: according to the UN 2004 projections, world population is projected to hit 8.9 billion in

2050, increasing by 47% with respect to 2000. Agriculture needs to keep growing, and EGNOS is there to help… for free.

Related Documents
1. Brochure - EGNOS for Agriculture
2. Presentation -"EGNOS: becoming the preferred GNSS technology in European Agriculture"
3. Leaflet - EGNOS for Agriculture
4. Advertisement - EGNOS for Agriculture - UK | FR | DE | IT

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