In the Middle East, water is never far from our minds. As Israel’s water shortage takes effect, the quality of our water is in brisk decline. Hot on the heels of this crisis, a team of researchers in Bar-Ilan University has developed an effective method for locating and measuring water contamination.
The new method, developed by Professor Zvy Dubinsky and Dr. Yulia Pinchasov, is based on the concept that contamination disrupts plant growth–therefore analyzing plant growth can serve to detect whether or not there is contamination.
The researchers analyze the rate of photosynthesis (the process of converting sunlight into energy) of plants growing in the water, to examine whether the plant is realizing its full photosynthesis potential. If it isn’t, this could indicate that there is a disruption in the water, i.e., a contaminant.
How does it work? Well, it starts with a green laser beam. Also, did you know that plants can sing?
The researchers radiate a green laser beam on the plant being examined. A plant that does not realize its full photosynthesis potential will utilize part of the laser light, converting this part into energy, with the rest being converted into heat. This heat causes the water to expand and therefore produce a change in pressure, which is actually a sound wave that can be picked up by a hydrophone–a special aquatic microphone.
Based on the quantity of light energy that is converted into heat and into sound, the researchers can calculate the remainder that has been absorbed by the plant, thereby learning about its condition.
For example, a plant suffering from lead poisoning will produce a different sound from a plant suffering from lack of iron, as well as a healthy plant.
This method replaces more outdated measurement methods that were used until now, being more effective and accurate. And the timing couldn’t be more poetic, all things considered.