from the world's big
We can assess the health of coral reefs by the sounds algae make
Tiny bubbles talk photosynthesis.
- During photosynthesis, algae produces a symphony of little "pings."
- The sounds are produced by oxygen bubbles breaking away from the plants.
- Monitoring reef health through its sound is a new avenue for acoustic ecology.
When oceanographers Lauren and Simon Freeman, a couple who work with the U.S. Naval Undersea Warfare Center in Rhode Island, first mentioned what they'd heard to others, the response was not exactly positive. They'd been listening to sounds they were certain had been made by marine macroalgae covering underwater coral reefs in Hawaii. Simon recalls, "We were told the sound was from snapping shrimp, end of story." But, listening at a few locations, they saw a correlation between the amount of sound and the quantity of algae. Further research has pretty much confirmed their hunch, and they've introduced a new avenue for marine acoustic ecology: Assessing the health of reefs according to the sounds they make.
Back up. Sounds the algae make?
An oxygen bubble about to ping and float upward. (Freeman, et al)
Algae, like plants on dry land, convert sunlight and carbon dioxide to energy via photosynthesis. The process releases tiny bubbles of oxygen to the surface. As each bubble lets go of the plant that produced it, there's a little "ping." As the Freemans' research states, "Many such bubbles create a large, distributed sound source over the sea floor." This 2 kHz – 20kHz hiss made of pings is what the Freemans have been hearing and recording from reefs.
There's actually quite a lot of acoustic goings-on underwater, between animal noises, human noises, waves, other bubbles and so on. Acoustic ecologist Erica Staaterman, not involved in the Freemans' research, says, "When I put a recorder in the water, I'm usually surprised by some cool new fish sound that I've never heard before. There's so much to discover."
As a result, recording and listening to algae in the wild is challenging.
To verify that the telltale pings were indeed coming from algae and not some other source, the Freemans set up a tank containing the invasive Hawaiian algae Gracilaria salicornia — no fish or crustaceans welcome. Upon listening, they heard the same high-pitched noise they'd witnessed at degraded reefs that no longer supported fish or other animals.
The value of this discovery
"Right now," says Simon, "reefs are evaluated visually by divers." Thorough research is an expensive and time-intensive endeavor, and findings are limited to what divers can see. The Freemans are hopeful that acoustic analysis of these environments will eventually reveal much more about reefs' conditions.
"In the future, it might be possible to quickly listen to a coral reef soundscape, perhaps by using an autonomous vehicle, and evaluate how it may have changed from the previous year."
Even now, a snapshot of a reef's algae cover can be quickly gleaned from its sound. (Other researchers are acoustically monitoring beds of sea grass in Australia.)
As Staaterman sees it, "Making these kind of links between bioacoustics and biodiversity is an exciting field with a lot of promise."
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Construction of the $500 billion dollar tech city-state of the future is moving ahead.
- The futuristic megacity Neom is being built in Saudi Arabia.
- The city will be fully automated, leading in health, education and quality of life.
- It will feature an artificial moon, cloud seeding, robotic gladiators and flying taxis.
The Red Sea area where Neom will be built:
Saudi Arabia Plans Futuristic City, "Neom" (Full Promotional Video)<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="c646d528d230c1bf66c75422bc4ccf6f"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/N53DzL3_BHA?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Many of the most popular apps are about self-improvement.
Emotions are the newest hot commodity, and we can't get enough.
Frequent shopping for single items adds to our carbon footprint.
- A new study shows e-commerce sites like Amazon leave larger greenhouse gas footprints than retail stores.
- Ordering online from retail stores has an even smaller footprint than going to the store yourself.
- Greening efforts by major e-commerce sites won't curb wasteful consumer habits. Consolidating online orders can make a difference.
A pile of recycled cardboard sits on the ground at Recology's Recycle Central on January 4, 2018 in San Francisco, California.
Photo by Justin Sullivan/Getty Images<p>A large part of the reason is speed. In a competitive market, pure players use the equation, <em>speed + convenience</em>, to drive adoption. This is especially relevant to the "last mile" GHG footprint: the distance between the distribution center and the consumer.</p><p>Interestingly, the smallest GHG footprint occurs when you order directly from a physical store—even smaller than going there yourself. Pure players, such as Amazon, are the greatest offenders. Variables like geographic location matter; the team looked at shopping in the UK, the US, China, and the Netherlands. </p><p>Sadegh Shahmohammadi, a PhD student at the Netherlands' Radboud University and corresponding author of the paper, <a href="https://www.cnn.com/2020/02/26/tech/greenhouse-gas-emissions-retail/index.html" target="_blank">says</a> the above "pattern holds true in countries where people mostly drive. It really depends on the country and consumer behavior there."</p><p>The researchers write that this year-and-a-half long study pushes back on previous research that claims online shopping to be better in terms of GHG footprints.</p><p style="margin-left: 20px;">"They have, however, compared the GHG emissions per shopping event and did not consider the link between the retail channels and the basket size, which leads to a different conclusion than that of the current study."</p><p>Online retail is where convenience trumps environment: people tend to order one item at a time when shopping on pure player sites, whereas they stock up on multiple items when visiting a store. Consumers will sometimes order a number of separate items over the course of a week rather than making one trip to purchase everything they need. </p><p>While greening efforts by online retailers are important, until a shift in consumer attitude changes, the current carbon footprint will be a hard obstacle to overcome. Amazon is trying to have it both ways—carbon-free and convenience addicted—and the math isn't adding up. If you need to order things, do it online, but try to consolidate your purchases as much as possible.</p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a>, <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a> and <a href="https://derekberes.substack.com/" target="_blank">Substack</a>. His next book is</em> "<em>Hero's Dose: The Case For Psychedelics in Ritual and Therapy."</em></p>
Building a personal connection with students can counteract some negative side effects of remote learning.