Scientists say just a few Asian carp may be big trouble for Great Lakes! and: Massive pumping of groundwater for cities said raising arsenic risks!

WATER WORLD

Scientist say just a few Asian carp may be big trouble for Great Lakes by Staff Writers Waterloo, Ontario (UPI) Sep 11, 2013


Massive pumping of groundwater for cities said raising arsenic risks New York (UPI) Sep 11, 2013 -Massive pumping of groundwater from a clean aquifer in Vietnam is drawing naturally occurring but poisonous arsenic into water supplies, scientists say.Natural arsenic pollutes wells across the world, especially in south and southeast Asia, where an estimated 100 million people are exposed to levels that can cause heart, liver and kidney problems, diabetes and cancer, scientists at the Earth Institute at Columbia University in New York reported Wednesday.

A study near the Vietnamese capital city of Hanoi confirms suspicions that booming water usage there and elsewhere could eventually threaten millions more people in south Asian and beyond, the researchers said.

“This is the first time we have been able to show that a previously clean aquifer has been contaminated,” lead author and geochemist Alexander van Geen said. “The amount of water being pumped really dominates the system. Arsenic is moving.”

There is some good news, he said: “It is not moving as fast as we had feared it might.”

This could give water managers time — perhaps decades — to find ways to deal with the problem, he said.

Researchers said they’ve linked natural arsenic pollution in south Asia to vast amounts of sediment eroding off the Himalayan plateau into basins below, from Pakistan and India to China and Vietnam.

The Hanoi pumping constitutes “a huge, unintended experiment,” study co-author Michael Berg at the Swiss Federal Institute of Aquatic Science and Technology said, noting  similar processes may be under way in other areas such as the megacities of Dhaka and Beijing and widespread farming areas of Asia, along with parts of sub-Saharan Africa, and South and North America, where irrigation and municipal pumping are sucking aquifers dry.

“We are altering systems all over the world,” he said.

 

A very small number of Asian carp — as few as 20 fish — could establish a population of the invasive fish in the Great Lakes, Canadian researchers say.

Scientist as the University of Waterloo in Ontario report under some conditions the probability of Asian carp establishment soars with the introduction of just 20 fish into the Great Lakes.

“Although established Asian carp populations including the Silver and Bighead carps are widely present in the Illinois and Mississippi Rivers, it’s expected that it’s only a matter of time before the population migrates through the many hydrological connections to the Great Lakes,” researcher Kim Cuddington said.

A mature Asian carp can grow as heavy as 110 pounds, and in competition for food — a mature carp consumes around 40 percent of its body weight daily — and space, the Asian carp has a significant size advantage over native fish species, the researchers said.

“This species will have a huge impact on the food web,” Cuddington said. “Not only is it a fast-growing fish physically, but the population itself grows very quickly. A female can lay well over a million eggs a year, and with no known predators present in the Great Lakes, the Asian carp could dominate the waters and impact fisheries.”

Individual carp have already been caught in two of the Great Lakes.

The probability of Asian carp establishment changes dramatically depending on the number of the creatures present, researchers said. With 10 fish, the probability of a population of Asian carp is only 50 per cent, but with 20 fish, it jumps to 75 per cent under some conditions.

Advertisements

One thought on “Scientists say just a few Asian carp may be big trouble for Great Lakes! and: Massive pumping of groundwater for cities said raising arsenic risks!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s