As predators decline, carbon emissions rise

February 18, 2013

(—University of British Columbia researchers have found that when the animals at the top of the food chain are removed, freshwater ecosystems emit a lot more carbon dioxide into the atmosphere.

" are disappearing from our ecosystems at alarming rates because of hunting and fishing pressure and because of human induced changes to their habitats," says Trisha Atwood, a PhD candidate in the Department of Forest and Conservation Sciences in the Faculty of Forestry at UBC.

For their study, published today in the journal Nature Geoscience, Atwood and her colleagues wanted to measure the role predators play in regulating to better understand the consequences of losing these animals.

Predators are bigger animals at the top of the food chain and their diets are comprised of all the smaller animals and plants in the ecosystem, either directly or indirectly. As a result, the number of predators in an ecosystem regulates the numbers of all the plants and animals lower in the food chain. It's these smaller animals and plants that play a big role in sequestering or emitting carbon.

When Atwood and her colleagues removed all the predators from three controlled freshwater ecosystems, 93 per cent more carbon dioxide was released into the atmosphere.

"People play a big role in predator decline and our study shows that this has significant, global implications for and ," says Atwood.

"We knew that predators shaped ecosystems by affecting the abundance of other but now we know that their impact extends all the way down to the biogeochemical level."

Explore further: Marine predators in trouble: researchers

More information: Nature Geoscience, DOI: 10.1038/NGEO1734

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1.5 / 5 (4) Feb 18, 2013
OMG! Does anyone wonder why there are so many who deny that global warming is real after reading this? Everyone and their dog scientist or not feels that if they can just incorporate climate change into their cause they can get the funds/attention to try and make a difference.

Does anyone know how much carbon I emit by working, going out occasionally, and doing things with my kids? What you need to do to stop Earth from becoming Venus is raise 2.5 million dollars for the Save-a-Dav foundation. With that money I won't need to work, can buy a Tesla, and uhhh. Do some other stuff to put an end this source deadly carbon emmissions.

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