New device can quickly map soil health in changing climate

Climate change will have — is having — a dramatic impact on agriculture around the globe, and one researcher has now developed a way to measure that impact with an “optical soil dipstick,” or OSD.

The OSD will help scientists, urban planners and farmers understand the changing health of the soil, as well as its agricultural potential and other associated concerns, according to its developer, Eyal Ben-Dor of Tel Aviv University’s department of geography.

“I was always attracted to drug development and diagnostics, which spurred the development of this OSD device,” Ben-Dor said. “It’s like a diagnostic device that measures soil health. Through a small hole in the surface of the earth, we can assess what lies beneath it.”

As climate change alters our planet radically, the dipstick could instantly tell geographers which regions are best — or worst — for farming. For authorities in California, it’s already providing proof that organic farms are chemical-free, and it could be used as a whistle-blower to catch environmental industrial polluters.

The benefits of the OSD were recently described in the Soil Science Society of America Journal.

Currently, there are no simple and inexpensive ways to test for soil health in the field. In the US, soil maps of individual states are compiled only every 10 or 20 years, at a cost of millions of dollars each. One testing process even requires the use of a bulldozer, which dredges up large tracts of land to be sampled and analysed in a laboratory.

Ben-Dor’s device, on the other hand, can even be used by non-professionals. The thin, catheter-like device is inserted into a small hole in the soil to give real-time, immediately accurate and reliable information on pollution and the all-around health of the soil. Analysing chemical and physical properties, the OSD outputs its data to a handheld device or computer.

“To optimise production and save costs, farmers need to know if their crops are getting the right blend of minerals,” Ben-Dor said. “This tool could permit them to pursue ‘precision agriculture.’ ”

The OSD, which is expected to cost about $10,000 per unit per application, allows technicians to determine if the soil needs water or is contaminated. It also provides information about the condition of root zones where crops are growing. And the quality of information is identical to that provided by large government laboratories, according to Ben-Dor.

The devices could even be remotely and wirelessly networked to airplanes and satellites to generate detailed, comprehensive and reliable soil maps.

Soil maps are important tools for land developers, city planners, farmers and environmental prosecutors. The maps used today tend to be outdated, rendering them useless for many applications, and only about 30 per cent of the planet has been mapped in this way. Soil maps for the Far East, the Arctic and Africa, which can be more readily developed with the OSD, will better help scientists, researchers and government agencies determine how climate change and population growth are affecting the planet and its resources.

“Soil mapping is a national undertaking,” Ben-Dor said. “It takes years and millions of dollars worth of manual labor and laboratory analysis, not to mention exhausting headaches with government authorities and ministries. For a fraction of that energy and money, and with a staff that has minimal training, the OSD could do the same job, and could continue doing it on a yearly, monthly, and possibly even a daily basis. The headaches would be gone, and we would finally get an accurate picture of the Earth’s crust in these environmentally critical years.”

The OSD is currently in a prototype stage and is set for commercialisation. If the right strategic partner is found, a new device could be on the shelves, and in the ground, within the year, according to Ben-Dor.