Earth Rover Program

The Earth Rover Program uses novel techniques of seismology to measure properties of soil which are very important, but extremely difficult to measure by other methods. The program has been funded with US$4m from the Bezos Earth Fund.^[1]

Attempts to measure typically require digging, which is ineffective and labour-intensive—simply estimating the volume of soil in a field needs hundreds of core samples—and destroys the soil structure that is being studied. Measuring compaction or porosity is very important but even more difficult. The lack of information on soil has impeded the development of farming that combines high yields with low environmental impact—low impact alone using existing techniques reduces yield, so that more land is required to be farmed, increasing total impact. While development costs have been high, it is hoped ultimately to develop techniques that can be used at virtually no cost. For example, in 2022 sensors required cost $10,000. The project found that a $100 geophone developed by a Slovakian experimental music outfit was just as effective. The project in 2025 was developing a sensor costing about $10, and hoped ultimately to be able to use the accelerometers in all mobile telephones, at zero cost.^[1]

A farmer named Iain Tolhurst had over decades developed methods of increasing yield combined with low environmental impact, without fertiliser, animal manure, or pesticides. His techniques appear to enrich the vital relationships between crops and soil microbes through which soil nutrients must pass. It is as if he had "trained" his soil bacteria to release nutrients when his crops require them (mineralisation), and lock them up when crops are not growing (immobilisation) so that they do not leach from the soil. However, not all farmers who adopted Tolhurst's methods succeeded; this is thought to be due to lack of knowledge of soil properties, and the Earth Rover Program hopes to eliminate guesswork so that high-yield low-impact farming becomes reliably possible.^[1]

With current farming technology it is not known exactly what the soil needs, so that many inputs such as fertilisers, irrigation, and deep ploughing are wasted. About two-thirds of nitrogen fertiliser used and 50% to 80% of phosphorus is not taken up, but causes algal blooms in rivers, dead zones at sea, waste of huge amounts of irrigation water, and global heating. If soil is thought, incorrectly, to have become compacted, farmers resort to deep (and damaging) ploughing.^[1]

References

1. Monbiot, George (5 December 2025). "Over a pint in Oxford, we may have stumbled upon the holy grail of agriculture". The Guardian.