London: The extinction of large animals could hasten climate change as their presence in tropical forests help in dispersing tresses with dense wood which are more effective in storing carbon dioxide from the atmosphere than smaller trees.
The reduction of large animals from tropical forests could make climate change worse as these animals are essential in scattering trees with dense wood.
A decline in fruit-eating animals such as large primates, tapirs and toucans could have a knock-on effect for tree species, the findings showed.
“We show that the decline and extinction of large animals will over time induces a decline in large hardwood trees. This in turn negatively affects the capacity of tropical forests to store carbon and therefore their potential to counter climate change,” said one of the researchers Carlos Peres from University of East Anglia in England.
Large animals disperse large seeded plant species – often associated with large trees and high wood density — which are more effective at capturing and storing carbon dioxide from the atmosphere than smaller trees, the researchers explained.
The research team studied data from more than 2,000 tree species in Brazil’s Atlantic Forest, and more than 800 animal species.
They found that frugivores which are not targeted by hunters — such as small birds, bats and marsupials — are only able to disperse small seeds, which are associated with small trees.
Meanwhile large heavy-wooded trees, which can capture and store greater amounts of carbon, are associated with larger seeds. And these are only dispersed by large animals.
“The big frugivores, such as large primates, the tapir, the toucans, among other large animals, are the only ones able to effectively disperse plants that have large seeds. Usually, the trees that have large seeds are also big trees with dense wood that store more carbon,” Prof Mauro Galetti from Sao Paulo State University in Brazil explained.
The findings appeared in the journal Science Advances. (IANS)(image courtesy: timedotcom.files.wordpress.com)
Worsening extreme weather linked to climate change is creating hardships for many, from immediate deaths and injuries to increases in asthma and heat stroke. But the psychological trauma that often accompanies such losses is barely on the map.
Depression, anxiety, suicide and post-traumatic stress disorder tend to increase after floods, storms, wildfires and heat waves, according to the American Psychological Association (APA), which represents psychologists in the United States.
“The problem with that link is it’s not like so obvious. It’s not like I stick a needle in you, you feel pain right away,” said Anthony Ng, former head of the APA’s caucus on climate change and mental health.
“Some of this is so insidious and gradual that people won’t realize it until it’s too late. That’s why it’s hard for a lot of people to appreciate it.”
The debate over how to safeguard residents of picturesque Ellicott City, a tourist draw an hour’s drive north of Washington, D.C., illustrates the challenges many towns are facing as the world becomes warmer and wetter.
The town was devastated in 2016 by a so-called 1,000-year flood — meaning a magnitude with a one-in-1,000 chance of occurring in any year. The Patapsco River, which runs through the town, rose more than 13 feet in less than two hours.
Less than two years later, a 1,000-year storm struck again, overwhelming the tributaries that converge under the old mill town’s buildings and feed into the Patapsco.
Warmer temperatures are increasing heavy downpours, and rainfall has been growing in intensity in the Northeast, according to the government’s 2018 National Climate Assessment, risking power outages and the viability of roads and bridges.
As Ellicott City has become more built up, floodwater flows across paved roads and rooftops, instead of percolating down through the soil as it used to — a phenomenon known as urban runoff, which is worsening globally as cities grow.
In the wake of the 2018 floods, the county launched the Ellicott City Safe and Sound plan, which involves demolishing some old buildings, making tunnels to carry water under roads and clearing waterways more regularly.
Officials are also testing a flood warning system, with emergency sirens telling people to move to higher ground. It has caused some alarm among residents, said Amy Miller, a social worker at the Grassroots Crisis Intervention Center.
“You almost have a panic response,” said Miller, whose non-profit organization, based in Columbia, some 8 miles (13 km) south, has provided food, shelter and support to flood survivors.
“We’re basically exposing ourselves to the perceived threat of a traumatic event.”
Grassroots provides 24-hour counseling to people in Ellicott City and the surrounding rolling hills of Howard County who might be feeling suicidal.
Miller has trained farmers to watch out for each other and spot signs of danger, particularly suicide risks.
Farmers are a high risk group. They tend to live solitary lives, have access to lethal means and face financial stress when hit by poor weather and low prices — factors they cannot control, according to anti-suicide campaigners.
“When your livelihood is impacted, that causes hopelessness,” Miller said. “The hard part for farmers is they work almost 24-7, and it’s really hard for them to seek treatment.”
Stanford University predicted last year that a hotter planet could lead to a surge in suicides by 2050. Its data analysis found suicides had risen 0.7% in the United States and 2.1% in Mexico with a 1°C increase in monthly average temperatures.
The researchers also found — by analyzing the language used in more than a half billion Twitter posts — depressive language increased during hot weather, suggesting worse mental health.
Keith Ohlinger, one of the Howard County farmers trained to keep an eye out, said he was driven to the work by the suicide of a young friend who grew up on a nearby farm, planned a career in agriculture and took her own life last year at age 21.
He struggled this spring with heavy rains washing away seeds and soil and leaving hay too wet to be dried and stored for winter feeding.
“Things are changing,” he said. “The Earth is changing, patterns are changing. Things are melting.”
Ohlinger uses his position on the Maryland Agricultural Commission, which advises the government on farming, and at monthly farmers club meetings to bring up mental health, often taboo in the conservative agricultural community.
He said climate change was just one more stress for farmers already worried about commodity prices, credit, bank loans, the price of equipment and old family-run farms being squeezed out by more and more giant residential homes known as McMansions.
“I can’t fix pricing. I can’t fix what the Chinese president or Donald Trump does, but I can surely try and keep someone from killing themselves,” Ohlinger said.
Not everyone in the region is willing to make the link between mental health problems and climate change.
Global warming as a manmade phenomenon is a politically divisive topic in the United States, where President Donald Trump announced plans to withdraw from the Paris agreement, a global pact to fight climate change.
“You talk about global warming, but we deal with this stuff all the time,” said another Howard County farmer, Howie Feago.
“Most farmers believe it’s more of an ebb and flow. We know that the weather is going to be up and down. If you’re going to worry about global warming, you probably ought to get some other kind of job because it will drive you nuts.” (VOA)