Thursday, April 22, 2004

Organic: Is it the future of farming?

Organic farming, which began in 1940s Britain out of a concern for the richness and stability of the soil, restoring its organic matter and avoiding synthetic fertilizers, pesticides and herbicides, and has more recently been identified with a green, holistic social mindset, is now poised to break into the farming mainstream.

These ideals have always set the organic movement squarely against intensive farming and chemical-based agribusiness. And, at least in public and in the media, those arguments rage more fiercely today than ever before. Yet behind the harsh rhetoric, a little-noticed convergence of views is taking place. For decades, the study of organic farming sat on the fringes of the green revolution in agriculture, as intensive techniques marched across the world, sending yields skyrocketing. But mainstream agronomists are becoming concerned about the long-term sustainability of this approach, and are focusing increasingly on soil integrity. Could it be that both sides of agriculture's great divide now want the same thing?

"It's been a huge move," says Mark Alley, an agronomist at Virginia Tech in Blacksburg. "Twenty-five years ago, yield was everything. But in the past ten years, there's been a major recognition of the need to maintain organic materials in soil." And with the turn of the millennium, farmers have started to embrace approaches that keep soil structure intact and cut the high level of inputs — energy, fertilizer, pesticides and herbicides — that characterize intensive agriculture. ...

The change that is taking place — sometimes referred to as the second green, or doubly green, revolution — stems from a growing acceptance of the organic critique of the first one. Mainstream agronomists now acknowledge, for example, that intensive farming reduces biodiversity, encourages irreversible soil erosion and generates run-off that is awash with harmful chemicals — including nitrates from fertilizers that can devastate aquatic ecosystems.

For the organic movement, caring for the soil involves interspersing each harvest with a cover crop such as clover or rye that can fix nitrogen from the atmosphere. Cover crops keep down weeds, retain moisture and prevent erosion. Ploughing them into the soil at the end of the season restores the soil's organic content, and boosts its nitrogen content without the need to use synthetic fertilizer. ...

Some of the other ideas being borrowed from the organic movement — in particular a reduction in pesticide inputs — are resulting in a closer meeting of minds. For instance, farmers have been forced to discard methyl bromide, the main soil fumigant that has been used to kill soil pests, as it will be phased out by 2005 under the Montreal Protocol to close the ozone hole. This has led farmers to experiment not only with other fumigants but with organic methods of killing insect larvae as well, including flooding fields between plantings and allowing the Sun to bake the soil through clear plastic sheeting.

Already some 2 percent of the world's farming acreage is being farmed with organic, low-till methods, about a third of that in the U.S. Low till farming is gaining popularity in such countries as Brazil, India and China. This is an important first step toward a sustainable agriculture.


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