Elevating Agricultural Sustainability in Europe: Satellite-based Fertilizer Recommendations for Decision Makers

Field specific Fertilizer rate recommendations and farm specific Fertilizer demand estimation have been a decade old?problem.? Soil testing and plant tissue testing are still regarded as the most dependable solutions. However, this is a time-consuming and labour-intensive process.? The closest alternative are the field sensors, which use the Near Infrared (NIR) light reflectance of plant leaves to estimate Fertilizer application?rates.? This technology has made life simpler, but it still requires field scouting as well as a large initial investment. Historically, scientific groups have developed several crop models that provide an efficient solution for Fertilizer advice. However, crop models are complicated and require high-quality soil and meteorological data, which we do not have at the field scale. On the contrary, the satellite image-based Fertilizer recommendation method eliminates the need for field scouting and useful for Variable Rate applications, however it fails to?address the rate recommendation challenges.

Spacenus GmbH is a satellite remote sensing company that has been working on this problem since 2017. Spacenus developed a solution to detect plant nutrient status in the lab, which was then transferred to the field condition, allowing us to estimate plant nutrient demand from satellite imagery and provide plant need-based, site-specific Fertilizer rate recommendations. The system has been tested with farmers throughout Europe from 2018 to 2021 and has proven to be beneficial to farmers in terms of Fertilizer input cost savings and complying with various European Fertilizer regulations.

?Since 2021, Fertilizer prices have begun to rise dramatically, triggering some interest among Fertilizer manufacturers and retailers?in predicting location-specific Fertilizer demand and enabling data-driven digital sales. This requires Fertilizer rate recommendations at the regional level. Using historical satellite images, we have begun to?analyse?each and every?field in Europe to identify crop and field specific nutrient uptake?during the previous five years. Those crop-specific nutrient uptake?estimates were aggregated into districts level, which were then revised?depending on district-specific yield, soil, and weather conditions, resulting in district-specific, crop-wise Fertilizer rate recommendations for the entire Europe.

?Regional Fertilizer rate?recommendations are a very simple tool but extremely helpful to improve fertilizer use efficiency across geographies and efficiently enforcing Fertilizer regulations at the local level. The blanket rate recommendations at the national or state levels are ineffective because they penalise high-yielding areas while allowing excess Fertilizer to leak into the environment in low-yielding areas. We took it a step farther for Germany. We wanted to figure out how much more value we could contribute by producing post-code-based Fertilizer rate recommendations. The end result was great. It provides additional details, which might be quite useful in advising and controlling Fertilizer use even?at the post-code level. This will eventually assist farmers to?grow food more sustainability?while also improving the quality of the environment over time.

Above, we propose Fertilizer rates for a wheat crop in Europe. Because of the post-code-based recommendation in Germany, the spatial rate recommendation resolution is high, but in the rest of Europe, the recommendation is currently at the district level. We compared our recommendations to?crop-specific Fertilizer use by nation, and it appears to be fairly aligned. The wheat?yield?in western?Europe is higher, so recommendations is?relatively higher. The yield gap in the?Eastern?Europe is large, so the recommendation remains quite low. In the future, we intend to expand it up to the postcode level for all of Europe and make similar maps available internationally.

To our knowledge, this is the first?map of its kind?that includes regional-specific Fertilizer rate recommendations, making it an excellent tool for policymakers, environmental specialists, Fertilizer manufacturers,?retailers, food companies, water supply companies, and many more. We envision a future in which such a tool serves as a standard that helps in the streamlining of?various?activities?such as creating policies, ensuring?environment-aware?field activities, fighting climate change, and delivering sustainable food to all of our plates.