Burning Fossil Fuels Reduces Diversity In Wet Regions, Study Suggests
Coal is big in Utah. It's our state rock and according to the US Energy Information Administration, it represents one-third of our state's total energy production. But Utah's coal may be having unexpected consequences on the grasslands and wetter places in the nation.
“When fossil fuels like coal or oil are burned, those are actually old plants that are stored in the earth and have not decomposed yet. So, we are decomposing them – breaking them apart – and using the energy that was stored when they were living plants,” said Dr. Elizabeth Borer, a professor at the University of Minnesota who recently lectured at Utah State University.
“We’ve communicated this idea that carbon is being put into the atmosphere when we burn those old plant parts, but there are other elements that are involved in making a plant that are also being put into the atmosphere when we burn old plant parts. Nitrogen and sulfur are being put into the atmosphere. Because nitrogen is so soluble in water. It comes up into the atmosphere and is dissolved in clouds, and then it comes down in rain. It is moved to certain locations where it rains,” she said.
When fossil fuels are burned, not much of their nitrogen comes down in Utah’s rain, because the state is so dry. The nitrogen tends to be deposited in wetter states. When Borer looked at the rates of nitrogen deposition in the context of a global grassland experiment network, she noticed something surprising.
“By mapping our data onto nitrogen deposition data, we’ve found there’s a loss of diversity that’s happening in natural grasslands around the world. That’s the first time that’s been shown – we’ve never been able to look at it on a global scale before. There’s greater production, more plant mass growing in these locations with high nitrogen coming out of the atmosphere, and lower numbers of species in those locations,” Borer said.
Borer stresses that losing species in wetter regions can have cascading consequences to soil fertility, pollinator availability and water quality.
“Species diversity underlies a lot of the services and goods we get from the environment free of charge. When we lose species out of environments we lose some of those services,” Borer said.