A newly published UBCO study has revealed an unexpected source of CO2 emissions in the region – the natural salts in the Okanagan Lake water used to grow fruit.

The research, published in the journal Geoderma, was led by biology professor Melanie Jones.

It involved working in a drip-irrigated apple orchard, where scientists analyzed the air coming from dynamic soil respiration chambers.

The tests were repeated with varying sources of water, including irrigation water from the lake.

“It turns out that some of the CO2 released after irrigation comes from the natural salts—bicarbonates—dissolved in water from Okanagan Lake as it is applied to the soil,” researcher Andrew Midwood said.

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“It’s a process we had not considered until we noticed some unusual results when we traced the source of the CO2. ”

But his colleague and co-author of the study, Kirsten Hannam, emphasized that this is a “natural process”.

She added: “Our results have to be considered in a broader context. Irrigation is essential to fruit production in the Okanagan Valley. Along with causing the release of CO2, from bicarbonates in the water, irrigation is also promoting the removal of CO2 from the atmosphere by encouraging plant growth.

“It’s a balance and to understand the balance, you need to know all the component parts.”

The authors said their research has practical applications for any agricultural communities in arid regions, particularly if they rely on an alkaline lake for irrigation.

They also warned that CO2 emissions are likely to rise as irrigation expands in dry climates.

Increasing organic matter in soil is of crucial importance, the authors added, because it can store converted for CO2 centuries.

Professor Jones explained: “This large natural carbon store is hugely important in combating rising atmospheric CO2 levels and it’s essential to understand all the carbon transactions that take place in soil.”