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Plants Make Sounds | Earth Wise

May 9, 2023 By EarthWise Leave a Comment

Some people talk to their plants. It is highly unlikely that the plants are listening, but recent research has found that plants are doing quite a bit of talking of their own.

It turns out that plant emit a variety of click-like sounds, especially when they are stressed in some way, such as being dehydrated or injured. The sounds are actually fairly loud – comparable to the volume of human speech – but occur at frequencies well above the range of human hearing.

The study at Tel Aviv University in Israel monitored plants in a greenhouse that were subjected to various stresses over time. Unstressed plants emitted less than one sound per hour, on average, while stressed plants emitted dozens of sounds every hour.

Recordings of the plant sounds were analyzed by specially developed artificial intelligence algorithms. The algorithms learned how to distinguish between different plants and different types of sounds. Eventually, they could identify the plant and determine the type and level of stress from the recordings. They could even do this in a greenhouse with a great deal of background noise.

The study resolved a very old scientific controversy about whether plants emit sounds. Not only do they, but the sounds contain useful information. We don’t yet know what the mechanism is for plant sounds. It is likely that in nature, the sounds are detected by various animals and perhaps even plants that can detect the high frequencies. And perhaps they react to them as part of seeking food, shelter, or other services that plants provide. Given the right tools, we humans may also be able to make use of the sounds being made by plants.

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Plants Emit Sounds – Especially When Stressed

Photo, posted February 20, 2009, courtesy of ProBuild Garden Center via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Life In The Great Pacific Garbage Patch | Earth Wise

June 14, 2022 By EarthWise Leave a Comment

The world’s oceans contain five gyres, which are large systems of circular currents created by global wind patterns and the Earth’s rotation. Gyres act like gigantic whirlpools. Anything that floats into one of them eventually ends up in the center. Ever since floating plastic waste started entering the ocean, it has poured into these gyres and created so-called garbage patches. The largest of these is the Great Pacific Garbage Patch, located halfway between Hawaii and California. According to the Ocean Cleanup Foundation, the Great Pacific Patch contains at least 79,000 tons of plastic.

A recent study has shown that the garbage patch is not just a place where drifting plastics aggregate; it is also a place where drifting animals aggregate.

It turns out that the Great Pacific Garbage Patch is absolutely teeming with life, primarily small surface-dwelling animals that are collectively known as neuston. A ship surveying the garbage patch found that in some places, there were nearly as many neuston as there are pieces of plastic.

Typical creatures in the patch are blue dragon nudibranchs, Portuguese man-o-wars, anemones, sea snails, blue buttons (which are related to jellyfish) and hydrozoans. It appears that these creatures are reproducing within the garbage patch. Little is actually known about the life history and ecology of these creatures, so that studying the garbage patch is offering valuable insights to scientists.

Two nonprofit organizations are working to remove floating plastic from the Great Pacific Garbage Patch. Evidently, removing this existing pollution from the ocean is likely to have unexpected effects on the local ecosystem and is a source of at least some controversy. One thing that isn’t controversial, however, is that we need to stop the flow of plastic into the ocean.

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