By Sophie Harrington
When you think of farming, satellites probably aren’t the first thing that comes to mind. Yet in the coming years, farming may be more and more tied to the information gathered by satellites orbiting the globe. New technologies are being developed to integrate precision satellite data with farming practices around the world. These techniques hold the potential for not only increasing the efficiency and yields of farms, but also to reduce the environmental impact of intensive farming.
In the United Kingdom, a group of companies known as the Courtyard Partnership are hoping to revolutionize farming by providing in depth data from satellite imaging and soil analysis. By providing farmers with information on soil variation across their fields the group hopes to facilitate increases in yield while at the same time allowing the use of more environmentally friendly farming practices.
Soil brightness scanning by satellites provides information on soil texture, moisture, and organic composition which enable farmers to make distinctions between different soil types. This in turn allows soil inputs to be calibrated based on the specific soil “zone” determined through the combination of satellite imaging and soil sampling on the ground. Initially this could allow farmers to reduce wasted fertiliser by applying the optimum amount for each soil zone..
Later on, satellite images can also be used to provide data on chlorophyll cover, the pigment in plants which gives them their green colour. This acts as a proxy for plant nitrogen levels, which influence chlorophyll content. If the chlorophyll is lower than ideal, this can be compensated for by increasing fertilizer input. At the same time, the satellite images also provide data on the “Normalised Difference Vegetation Index” (NVDI). This provides a measure of crop growth (or “thickness” on the ground).
With this data, farmers are more able to monitor the total health and growth of their crops on a large scale. Indeed, the digital files containing the satellite data, and thus the corresponding chlorophyll and NVDI levels, can be tied to the farm machinery, allowing automatic changes in inputs ranging from seeds to fertiliser. This type of high precision data has the potential to dramatically decrease pollution and fertiliser waste. According to the Courtyard Partnership, use of such techniques could lead to savings of 45 tonnes of carbon dioxide emissions, as well as significant decreases in fertilizer use.
Considering the serious environmental consequences that have stemmed in part from the industrialization of farming, such techniques seem promising. The extensive application of fertilizers since the Green Revolution of the 50s and 60s have indeed led to increases in agricultural production, but at serious costs. Fertilizer runoff into rivers and streams has been implicated in significant algal blooms. The dead zone of the Gulf of Mexico arises from the nitrogen and potassium fertilizer runoff polluting the Mississippi river. The resulting algal blooms cause hypoxia, or low oxygen levels, killing off much of the marine life in the area.
The concept of using satellites in agriculture may seem alien for now, but if we want to solve our problems on the ground we may be best off looking to the sky.