Researchers get their hands dirty in one of the last frontiers of science

Several researchers from across Canada have teamed up to get the dirt on dirt.

"It's fascinating because soil is one of the last frontiers," said Claudia Goyer of Agriculture Canada in Fredericton.

Goyer and her colleagues are attempting to collect and document all of the organic matter and micro-organisms in topsoil — with a focus on agricultural land and forests.

They'll compile the data in a soil map of Atlantic Canada.

"Soil is super important because that's what gives us food on our plates," Goyer said. 

"We're eating plants. Animals eat plants. It's very crucial to our life, basically."

Aided by students who were employed for the summer, the researchers dug up 250 soil samples this year in New Brunswick and Prince Edward Island.

They intend to collect another 250 next summer in Nova Scotia and Newfoundland and Labrador.

In the longer term, the plan is to map the soil of the entire country.

Most of the research will focus on the few centimetres closest to the surface, known as the A horizon. 

Agriculture Canada

But they also took some samples at depths of 30 to 60 cm to find out how carbon moves through soil. 

Erika Young of Memorial University of Newfoundland will analyze the nematodes and soil respiration.

Kirsten Hannam of Summerland, B.C., will look after fractionation — breaking the soil down to different parts.

Goyer's Fredericton colleagues, Louis-Pierre Comeau, Jessica Vickruck and Cameron Wagg, will respectively look at organic matter, micro-arthropods such as mites and the relationships, known as mycorrhizas, between fungi and plants.

Goyer's focus is on microbiology.

Soil has about 100 million bacteria and a million fungi per teaspoon, she said.

"It looks like it's inert … but it's actually very active."

And remarkably little is known about how all those life forms work together to cycle nutrients, feed plants, protect against pathogens and recycle carbon — some pretty key functions in ecosystems.

"I can go in your garden and have 20 to 30 per cent of the organisms that we don't know anything about."

All of that should soon change.

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There's been a recent boom in soil microbiology research, said Goyer, made possible by a new DNA testing method known as next generation sequencing.

Whereas before only a small portion of organisms in soil could be cultivated, now it's possible to get a much more complete picture of biological diversity.

Once we have a better idea what's in the soil and how it works together, we might also figure out ways to protect and boost food and forest production.

"That's the dream of all soil microbiologists on the planet, I think," Goyer said.

She also expects the study will provide important baseline data to monitor the effects of climate change.

Canada's growing season is expected get longer, but there will also be more frequent periods of drought and extreme rain events.

Agriculture Canada

Those extreme rain events are already taking a toll on New Brunswick soil, she said. The province is prone to run-off because of its rolling landscape.

"We're losing that very good A horizon — like the top part of the soil where most of the organic matter is and most of the organisms. And that is not good."

That's why some farmers in the potato belt have started using terraced fields, she said.

Another protection method is maintaining riparian zones, or strips of trees, that stop the soil from running into a stream.

"We're always looking for solutions so we make sure that soil stays where it should be."

Goyer suspects this data will be useful for farmers, foresters and policy makers.