Feature Articles

A gentle reawakening in agricultural soil conservation

April 14, 2010:

Six signs that farm soils are taking on new profile in environmental progress

Tom Goddard takes hand samples of barley crop at a site specific management test plot.
Tom Goddard takes hand samples of barley crop at a site specific management test plot.

They have always had a bit of a Rodney Dangerfield image, the comedian who made a long career out of never getting any respect. Soils, many in the industry would say, have simply not had the respect they deserve.

Across Canada farmers are switching to low tillage systems and conservation management that protects the soil from wind and water erosion. As another National Soil Conservation Week is acknowledged, April 18 to 24, 2010, there are signs that effort is paying off in a broader sense with soils inching their way up the public profile.

The indicators are in the subtleties of the language used to discuss them and a renewed interest in where food comes from says soils veteran, Tom Goddard of Alberta Agriculture and Rural Development. He has spent a lifetime in soil science, extension and most recently policy, and today is involved internationally.

"We used to talk soil conservation," says Goddard. "Today we talk soil quality and ecosystem services. These are more difficult concepts, more inclusive and expansive." They are signs, he believes of new knowledge and a gentle reawakening in interest of how agricultural soils affect the environment and all people.

New interest in soil complexity

Soils are complex systems and there is a greater interest in that. Not only do they provide food and fiber, they provide habitat, gene pools and are the filter, storage container and supplier of nutrients.

Soils hold and cycle nutrients from parent materials and biological materials such as crops, animals and insects. Soils can also hold "imported" nutrients, some intentional such manure or fertilizers, others unintended such as oil spills or contaminants.

"Soils can break down or metabolize many of these pollutants into less harmful substances or useful nutrients," he says. "The more we care for soils to keep them in top condition, the more they can do for us."

Site specific management.

One of the most dramatic developments in soils management is site specific management (SSM), a convergence of new technologies with agronomic science that recognizes soil differences and makes the most of them.

Tom Goddard prepares soil cores as teaching aids to show how soil organic carbon varies under different farming practices.
Tom Goddard prepares soil cores as teaching aids to show how soil organic carbon varies under different farming practices.

As an example, SSM uses the latest Global Positioning Systems (GPS) and computing technologies such as touch screens allow farmers to measure crop yields every second a combine moves across a field. SSM technologies can vary application rates of fertilizers to the optimum for the specific soils the equipment is travelling over, or automatically shut off sprayers around sensitive areas such as wetlands.

"The control is phenomenal," says Goddard. "These management systems look like mission control and in environmental terms are just as powerful."

New soil-driven marketing opportunities

Those sophisticated SSM tracking systems drive new marketing opportunities, says Goddard. There are more crop, livestock and production options available to farmers today and some of those can be targeted to specific market niches. But to certify a commodity is produced a certain way or comes from a specific region, data and tracking systems are needed.

"In Europe wines and cheeses are identified with regions and practices and we are starting to see that occur with other commodities," he says. "Argentina is exploring the certification of farm products produced with 'conservation agriculture' methods. Farmers must use no-till or direct seeding along with other practices."

Renewed appreciation for biodiversity

In gardening, people realize when they leave residue on the soil surface, they increase the number of insects and other organisms. It is becoming recognized how much the low tillage systems used in farming across Canada today add to biodiversity.

Not only does residue of low tillage systems reduce erosion and nutrient loss, insects on the surface attract other members of the food chain that feed off them. Some of the researchers have tracked incidence of songbirds, earthworms and insects on the surface and been able to demonstrate that biodiversity is greater in low tillage systems than in conventional tillage.

Carbon storage potential

Soils are becoming recognized around the world as biological carbon banks, says Goddard. Newer direct seeding practices can help store carbon, the essential component of organic matter, in the soil.

Agriculture has developed protocols for operations that can reduce emissions and sequester or store carbon. The carbon market is a recognition of soils providing ecosystem services for the greater public good. Some countries are recognizing the additional public benefits such as nutrient filtering, water regulation and biodiversity, and are directing funding to enhance these services.

The heritage value of quality soil

Canada's soils, like the black prairie soils of western Canada, are recognized around the world as having real heritage value for being high quality soils, very productive and free of impediments. Their grassland origins put high organic matter into the soil and the cool climate prevents it from being oxidized quickly.

Canada's farmers are building their own heritage value. Farmland that is well cared for is becoming recognized for having significantly greater value when it is sold, than soil that has not been cared for. That has direct benefit to producers and helps drives good management practices.

"There is a renewed interest in thinking of natural landscapes in heritage terms," says Goddard. "Soil is the foundation of sustainability, good food and good environment, so it's natural it would be considered the same way."