Healthy watersheds start with healthy soil

Soil is the foundation of healthy farms, forests, cities and watersheds. Yet we are failing, collectively, to take care of soil health, and it is starting to catch up with us.

Losing soil health is linked to a number of concerns in the Kettle River watershed. Our streams and rivers are carrying more silt, nutrients and pathogens.

Stormwater from intense rainfalls travels quickly over compacted soils and urban landscapes to pollute our streams. And nitrates and other contaminants infiltrate our sandy soils and contaminate groundwater.

Globally, mismanagement of soils is threatening food production, harming coral reefs, releasing carbon dioxide and other greenhouse gases, and creating algae blooms and vast ‘dead zones’ in lakes and oceans.

So what can we do? It turns out that taking care of our soils means learning about their hidden mysteries as ecosystems.

“We need to learn how to give back,” says Sheila Dobie of the Grand Forks and Boundary Regional Agricultural Society. “Composting, growing cover crops to return energy to the soil and rotating crops so we don’t deplete it – there are many things gardeners and farmers can do to help the soil food web.”

Straw mulch and lettuce protect the soil while young cucumbers grow
Straw mulch and lettuce protect the soil while young cucumbers grow

Recent studies show that soil contains one third of all of the world’s organisms. One teaspoon alone can contain billions of microbes of thousands of different types.

When a leaf falls or a plant dies in healthy soil, earthworms and termites quickly tear it apart and consume it. Fungi and microbes continue the work and make the nutrients available to growing plants to continue the cycle.

But modern, mechanised and chemical-based farming destroys the food webs in the soil, and rapidly breaks down the structure that keeps soil together. Heavy nitrogen fertilization and tilling literally burns off the carbon stored in the soil by stimulating the microbes which use it as fuel.

In fact, nearly a third of the world’s cropland is losing soil faster than it is gaining. According to Lester Brown of the Earth Policy Institute, “Soil that was formed on a geological time scale is being lost on a human time scale.”

Soil is also disregarded when developing urban areas, and it needs to be stewarded carefully on ranches and forestry operations to prevent erosion and loss of productivity.

Because of their knowledge of building soil without chemicals and pesticides, we can turn to organic farmers to learn more about restoring soil health.

Organic farmers have learned to keep the soil covered with soil-building crops like fall rye, buckwheat and clover. Clover can even be interplanted with other crops to give a boost of nitrogen to the crops, at a fraction of the cost of conventional fertilizer.

Incorporating perennials, shrubs and trees in working farms can also reduce wind and water erosion and provide mulch and compost inputs for crops.

“One of the biggest things we can do around here is composting,” says Dobie. “It breaks my heart to see us burning and polluting the air when all of that crucial organic matter could be returned to the soil, with even less work than burning.”

Over the coming months, the Stakeholder Advisory Group will examine many ways of supporting healthy aquatic ecosystems and water supplies in the Kettle River watershed, including stewardship of the soil.

Further reading:

— Graham Watt is the coordinator of the Kettle River Watershed Management Plan for the RDKB, and is working with a Stakeholder Advisory Group from across the region to develop the plan. Email [email protected]