Belgian farms tackle soil erosion

By Alix Kroeger
BBC News, Huldenberg, Belgium

Deep lines show erosion on the ploughed section of land

By mid-August, the maize in Jos Peeters' fields has grown to more than 2m (6ft) in height.

A dividing line runs down the middle of one field, but it is only visible at ground level.

One side has been tilled using a conventional plough, the other using conservation methods.

On the conservation side, the roots of the maize plants have remained covered.

On the ploughed side, rainfall has washed away the top layer of soil from around the roots, creating runnels that trace lines down the hillside.

It is a small-scale demonstration of the effects of erosion, which is washing away more than 200 tonnes of arable soil across Europe each year.

Conservation method

Mr Peeters and his brother Jan farm 100 hectares (247 acres) in the village of Huldenberg, 15km (10 miles) south-east of Brussels. For nearly a quarter of a century, they have been involved in trials of conservation agriculture, monitored by the Catholic University of Leuven.

Now, based on the success of the trials, they are helping to convince other farmers to change their ways.

Today, when I talk with other farmers, they start to believe it can work. Twenty years ago, they would just start to laugh Jos Peeters Belgian farmer

Conservation methods have been used in North America for many years. Under the "no-tillage" system, farmers stop ploughing their land altogether.

They leave vegetable residues on the land to form a mulch, which stops the soil from being washed away by rainfall.

But sometimes "no-tillage" is not practical, so there is also what is called "conservation tillage," which uses a lighter touch than conventional ploughing.

Special machines

Instead of turning the soil upside down and uprooting weeds, farmers use specially designed machines to loosen the top 6in (15cm). This makes planting easier but still leaves the vegetable mulch on the surface.

"Even a small amount of mulch makes a big difference," says Gerald Govers, professor of geography at Leuven University. "If even 20% of mulch is left, erosion is down by 70% to 80%."

In the area around Jos Peeters' farm, Professor Govers estimates the run-off from 50 hectares (123.5 acres) of conventionally ploughed land could be as much as 1,000 litres per second after heavy rainfall, such as Belgium has experienced for the past few weeks.

That run-off could be carrying up to 200kg (440lb) of topsoil erosion.

Savings

Erosion is not just a problem for farmers. The run-off from heavy rainfall carries sediment and agrochemicals into watercourses. The local authorities then have to pay for these to be cleaned up.

Under conservation agriculture, Jos Peeters admits his yields are down by 5% to 7%. But he says that is offset by the money he saves on fuel and labour costs by not having to plough. The mulch also improves the organic quality of the soil.

"Today, when I talk with other farmers, they start to believe it can work. Twenty years ago, they would just start to laugh," he says.

And Mr Peeters says his relations with his neighbours are better, now that less soil from his land is ending up on local roads or silting up streams. Now, most of the run-off is just water.

Government incentives

The Belgian government is now paying farmers 200 euros (£136) a year for each hectare they leave unploughed.

It is an incentive for farmers to change their methods. And although farmers have to buy new machinery, unlike organic agriculture, there is no lengthy conversion period, when land is taken out of production.

"The government only supported conservation tillage when it saw it worked," says Gerald Govers. "That's a political decision."

The UN Food and Agriculture Organisation (FAO) says conservation agriculture can even help against global warming. The extra organic material from the vegetable mulch stores carbon dioxide, keeping it out of the atmosphere.

"Conservation farming applied on a global scale could provide a major contribution to control air pollution in general and global warming in particular," the FAO says on its website.

"Farmers applying this practice could eventually be rewarded with carbon credits."