British Columbia

Could soil be the next carbon sink? UBC Okanagan to lead study

Amid renewed attention on climate change, UBC Okanagan is getting $1.4 million in federal funding to research the impact of irrigation on greenhouse gas emissions.

$1.4 million federal investment will fund 4-year research project on how to increase carbon storage in soil

A new study at the University of British Columbia Okanagan is looking at how irrigation can alter the amount of carbon in the soil and air. (Becks/Flickr)

The University of British Columbia Okanagan is getting $1.4 million in federal funding to research irrigation and its effect on greenhouse gas emissions.

The school is one of the beneficiaries of Ottawa's new $27 million Agricultural Greenhouses Program, which is supporting 20 research projects.

The funding boost comes amid renewed attention on climate change after the U.S. pulled out of the Paris climate agreement last week.

"These new investments are part of the government's commitment to addressing climate change and ensuring our farmers are world leaders in the use and development of clean and sustainable technology and processes," said Lawrence MacAulay, minister of agriculture and agri-food in a statement.

'Huge amount' of carbon in soil

Irrigation — the watering of land to prep it for agriculture — might not seem synonymous with climate change. But researchers at UBCO want to know how it affects the storage of carbon and nitrogen in soil.

"When we talk about climate change, we often discuss the concentration of carbon dioxide in the atmosphere. But actually a huge amount of carbon is stored in the soil," Kirsten Hannam, a research associate on the project, told CBC's Chris Walker on Daybreak South.

The buildup happens when carbon dioxide in the air is fixed by plants during photosynthesis and converted into leaves and roots. The carbon is deposited into the soil and accumulates over time.

The Okanagan Valley is known for its fertile agriculture. (Rosalee Yagihara/Flickr)

Irrigation has two possible effects on greenhouse gases, Hannam explained.

First, it can change the moisture content of the soil and release the accumulated carbon back into the atmosphere.

Alternately, irrigation can increase plant productivity — a common sight in the Okanagan Valley where grapes and pears grow in abundance.

Greater plant growth means more leaves and roots, which store more carbon dioxide in the soil and reduce carbon dioxide in the air.

Water's impact

The UBCO researchers want to identify the irrigation practices that have a positive effect on soil carbon storage, meaning more carbon in the soil and less in the air.

The distribution of the water in the soil, such as overhead sprinklers or drip irrigation, can affect that ratio. So does the amount of water used.

A green field of crops being sprayed by a long irrigation apparatus.
The amount of water used and how it is dispersed can affect the distribution of water in the soil. (Kyle Bakx/CBC)

"We're trying to take a very big picture of how much water we use, how much greenhouse gases we expend to distribute that water and how we best then accumulate carbon into the soil to reduce greenhouse gases in the atmosphere," Hannam said.

The team expects to wrap up its research by 2021.

"It's really wonderful to be able to participate in a project that's so important, useful and timely," Hannam said.

Listen to Kirsten Hannam's interview on Daybreak South: