'Soil dipstick': A thermometer for the Earth

October 1, 2009

According to climate change experts, our planet has a fever -- melting glaciers are just one stark sign of the radical changes we can expect. But global warming's effects on farming and water resources is still a mystery. A new Tel Aviv University invention, a real-time "Optical Soil Dipstick" (OSD), may help solve the mystery and provide a new diagnostic tool for assessing the health of our planet.

According to Prof. Eyal Ben-Dor of Tel Aviv University's Department of Geography, his soil dipstick will help scientists, urban planners and farmers understand the changing health of the soil, as well as its agricultural potential and other associated concerns. "I was always attracted to drug development and diagnostics, which spurred the development of this OSD device," he says. "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, Prof. Ben-Dor explains, this dipstick could instantly tell geographers what parts of the U.S. are best -- or worst -- for farming. For authorities in California, it is already providing proof that organic farms are chemical-free, and it could be used as a whistle-blower to catch environmental industrial polluters.

The efficacy of the OSD was recently reported in the Soil Science Society of America Journal.

"Precision agriculture"

Today, there is no simple and inexpensive way to test for soil health in the field. Soil maps of individual states are only compiled every 10 or 20 years, and each one costs millions. One testing process even requires the use of a bulldozer, which dredges up large tracts of land to be sampled and analyzed in a laboratory.

Testing can be much simpler with Prof. Ben-Dor's dipstick, which can 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-round health of the soil. Analyzing chemical and physical properties, the dipstick outputs its data to a handheld device or computer. "To optimize production and save costs, farmers need to know if their crops are getting the right blend of minerals. This tool could permit them to pursue 'precision agriculture,'" says Prof. Ben-Dor.

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, the researchers explain, is identical to that provided by large government laboratories. Prof. Ben-Dor says that these dipsticks can also be remotely and wirelessly networked to airplanes and satellites, providing the most detailed, comprehensive and reliable soil map of the U.S.

Saving money and avoiding headaches

Soil maps are important tools of the trade for land developers, city planners, farmers and environmental prosecutors. Those employed today tend to be outdated, rendering them useless for many applications, and only about 30% 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 Prof. Ben-Dor's dipstick, will better tell scientists, researchers and government agencies how climate change and population growth are affecting our planet and its resources.

"Soil mapping is a national undertaking," Prof. Ben-Dor observes. "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 commercialization. If the right strategic partner is found, a new device could be on the shelves, and in the ground, within the year.

Source: American Friends of Tel Aviv University