Nov 15, 2021 12:30:00

Organisms such as seals and seahorses are returning to the Thames, which was declared 'biological death' more than 60 years ago.

The River Thames, which flows through southern England, is a river that connects the British capital, London, and the sea, and has appeared in various creations set in London, but due to serious human pollution, it was 'biological' in 1957. Was sentenced to death. However, the water quality of the River Thames by purification effort in recent years has been dramatically improved, by a wide variety of creatures such as seals and sea horses are returning to the River Thames, is an academic organization of the London Zoological Society of London Has published a report investigating the environment of the Thames.

The State Of The Thames 2021 | Zoological Society of London (ZSL)
https://www.zsl.org/natureatheart/the-state-of-the-thames-2021

Zombie river? London's Thames, once biologically dead, has been coming back to life: NPR
https://www.npr.org/2021/11/11/1054645619/state-of-the-river-thames-report-london

Seahorses and sharks living in River Thames, analysis shows | Rivers | The Guardian
https://www.theguardian.com/environment/2021/nov/10/seahorses-and-sharks-living-in-river-thames-analysis-shows-aoe

The Thames is a London landmark that appears in various works such as 'Sherlock Holmes ' and ' Harry Potter ', but as London became the center of industry, the amount of factory effluent and domestic effluent that was drained increased, and in 1858. Had a record stink called ' Great Stink'. And in 1957, scientists at the Natural History Museum in London declared the Thames 'biological death' because it was too polluted to survive.

However, after that, the water quality of the Thames has improved dramatically due to the expansion of sewage treatment facilities and restrictions on industrial wastewater. The Zoological Society of London conducted a survey with the help of experts from more than 16 collaborative organizations to assess the ecosystem on the Thames. You can check the state of the survey in the following movie released by the Zoological Society of London.

Landmark State Of The Thamaes report launches --YouTube


Alison Debney of the Zoological Society of London measures a benchmark of how much the Thames environment has recovered now, more than 60 years after the Thames was sentenced to 'biological death.' It states that it is something to do.

Members investigated the water quality of the Thames and sediments on the banks of the river, as well as the number of bivalves that live in a certain area.

In 1957, when the Thames was declared 'biological death,' only a few eels lived, but by 2021, more than 115 species of fish, 92 species of birds, and sharks lived. , Seahorses, etc. inhabit.

Researchers put the found organisms in trays and check the types and numbers.

The Thames, where many organisms have returned, is said to also serve as a carbon dioxide sink to combat global warming.

'(The Thames) has a myriad of wildlife as diverse as London itself,' the report states. Was hardly observed until the early 2000s

harbor seals and gray seals that and that is so often seen in the Thames, breeding in the UK were severed until 1842 Pied Avocet is increased in the River Thames to have it, equalizing Que Iraq Buka , Starry smooth hound , dogfish shark has also been reported that the sharks, such as inhabit.

A survey of water quality on the Thames confirmed long-term improvements in water quality due to improved sewage treatment functions, such as an increase in dissolved oxygen , which is important for fish survival, and a decrease in phosphorus concentration, which causes problems such as red tide when excessively increased. I did.

While the report reports promising results, it also raises some concerns. While the long-term outlook for birds and mammals inhabiting the Thames has improved, the number of fish species has declined since the 1990s, and further research is needed to identify the cause. In addition, the increased concentration of nitrates due to drainage from cities also warns that water quality may deteriorate.

Another threat to water quality is that most of London's sewerage system was built in the 19th century, when the population was less than a quarter of what it is today, so untreated sewage flows into the Thames due to storms and other factors. It has become. However, construction of a large sewer called the Thames Tideway Tunnel is underway in London, and if construction is completed and operated as planned in 2025, untreated sewage can be prevented from overflowing the Thames. That is.

by Jorge Franganillo