What Plants Say About Pollution
We really have to listen to what plants have to say about pollution.
Scientists in Israel discovered that water pollution can be tested by "listening" to what algae have to say about the level of contamination. This could be done by shining a laser beam on tiny pieces of algae in the water and listening for sound waves that tell them about the type and amount of contamination in the water (Dubinsky's technique).
"It is a red light, telling us that something is beginning to go wrong with the quality of water," said Zvy Dubinsky, an aquatic biologist at Israel's Bar Ilan University. "Algae is the first thing to be affected by a change in water quality."
The secret to monitoring water quality through this technique is by measuring the rate of photosynthesis in the algae. When a laser is shone on the algae, some of the heat rebounds back into the water, creating sound waves. The amount of heat shot back depends on the condition of the algae. This is a relatively cheap and accurate way compared to the techniques now in use.
"Algae suffering from lead poisoning, like waste discharged from battery and paint manufacturing plants, will produce a different sound than those suffering from lack of iron or exposure to other toxins," said researcher Yulia Pinchasov.
She said that testing algae photosynthesis can determine water quality more accurately and easily than labor-intensive methods now used like chemical and radioactive carbon testing.
With proper funding, Dubinsky said a commercial product could be ready in about two years.
The team has published its research in numerous scientific journals, most recently in the journal Hydrobiologia.
Most of the oxygen in the atmosphere also comes from algae. Its over abundance and being readily avaliable further reinforces that Dubinsky's method is easy to perform.