east asia

Attack of the giant goldfish

January 15, 2024 By EarthWise Leave a Comment

Goldfish are just about the easiest pets to keep. A species of carp native to East Asia, they have been bred to look pretty and are generally little more than home décor. We keep them in little glass bowls and feed them mysterious flakes out of a container. With these confined quarters and meager meals, they remain small, harmless creatures. But released into the wild, it is a very different story.

People dump pet goldfish into lakes and ponds with some frequency. Once they are in the wild, these humble creatures can grow to monstrous proportions. They can eat nearly anything, including algae, aquatic plants, eggs, and invertebrates. They can kill off native marine wildlife and damage or even destroy fragile and economically valuable ecosystems.

For a few years, Canadian researchers have been tracking invasive goldfish in Hamilton Harbour, at the western tip of Lake Ontario, about 35 miles southwest of Toronto. That part of the lake has been decimated by industrial and urban development as well as by invasive species.

Goldfish were first spotted in the harbor in the 1960s, mostly died off in the 70s because of industrial contamination, but then recovered in the 2000s. Goldfish can tolerate a wide range of water temperatures, reach sexual maturity quickly, and can reproduce several times in one season. In resource-rich places, they can grow up to 16 inches long, making them too large a meal for many predators.

There are literally millions of goldfish in the Great Lakes and not only there. Feral goldfish are a problem in Australia and in the United Kingdom. Invasive species are a big problem, even if they start out small and cute.

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Once They Were Pets. Now Giant Goldfish Are Menacing the Great Lakes.

Photo, posted September 20, 2015, courtesy of Watts via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Nitrous Oxide Is No Laughing Matter | Earth Wise

November 10, 2020 By EarthWise Leave a Comment

Carbon dioxide is the most well-known of greenhouse gases. But there are others deserving of their own spotlight. Nitrous oxide is one of them. It turns out that the same “laughing gas” once used by dentists as an anesthetic is pretty bad for the environment. In fact, it’s more than 300 times more potent as a greenhouse gas than carbon dioxide, and it can remain in the atmosphere for more than 100 years.

According to a new study by a team of international scientists, rising nitrous oxide emissions around the world are jeopardizing the climate goals of the Paris Agreement. The growing use of nitrogen fertilizers in global food production is increasing atmospheric concentrations of nitrous oxide.

The study, which was led by Auburn University and recently published in the journal Nature, finds that nitrous oxide emissions are increasing faster than any emission scenario developed by the Intergovernmental Panel on Climate Change. The current trajectory would lead to global mean temperature increases well above 3°C from pre-industrial levels. The Paris Agreement aims to limit global warming to less than 2°C.

According to the study, nitrous oxide levels have risen 20% from pre-industrial levels, with the fastest growth observed in the last 50 years due to emissions from human activities. The largest contributors to nitrous oxide emissions come from East Asia, South Asia, South America, and Africa. The United States, China, and India dominate nitrous oxide emissions from synthetic fertilizers, while Africa and South America dominate releases of nitrous oxide from natural sources, like livestock manure.

Nitrous oxide emissions pose an increasing threat to the climate.

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Nitrous oxide emissions pose an increasing climate threat, study finds

Photo, posted April 22, 2012, courtesy of Bill Meier via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Bugs That Eat Plastic | Earth Wise

September 29, 2020 By EarthWise Leave a Comment

The world continues to struggle with the proliferation of plastic that is polluting the environment. The Great Pacific Garbage Patch has now grown so large that it has spread across an area four times the size of California. But there is no silver bullet in the struggle to reduce plastic pollution. Reducing the use of plastic is probably the most viable approach, but increased recycling, the use of bioplastics, and various other strategies must play a role.

The essence of the problem is that plastic takes from decades to hundreds of years to decompose naturally. The world produces billions of tons of plastic waste each year and less than 10% of it is recycled. As a result, researchers around the world seek ways to safely and economically accelerate the decomposition of plastics.

A research team at Andong National University in South Korea has discovered the larvae of a particular species of darkling beetle can decompose polystyrene, which is one of the trickiest plastics to break down. There are thousands of species of darkling beetles found in different habitats all over the world. The one they identified is indigenous to East Asia.

The beetle larvae can consume polystyrene and reduce both its mass and molecular weight. Furthermore, they found that the bacteria in the gut of the larvae could oxidize and change the surface property of polystyrene. The handful of bacterial strains they identified were not like those of earlier insects found to degrade polystyrene. As result, the researchers are hopeful that it may be possible to break down the plastic using other insects that feed on rotten wood. Apart from the insects themselves, using just the bacterial strains found in the darkling beetles may prove to be an effective method for decomposing polystyrene.

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A New Species of Darkling Beetle Larvae That Degrade Plastic

Photo courtesy of Flickr.

I farmaci a base di erbe e omeopatici rappresentano una percentuale significativa (circa una confezione su otto) dell’assortimento da banco delle farmacie. Nel 2017, i farmaci a base di erbe hanno registrato vendite per 1,48 milioni di euro e 120 milioni di confezioni, mentre maschioforte.com i farmaci omeopatici hanno registrato vendite per 630 milioni di euro e 52 milioni di confezioni, secondo l’Associazione federale dell’industria farmaceutica (Bundesverband der Pharmazeutischen Industrie – BPI).

Earth Wise is a production of WAMC Northeast Public Radio.