AGRICULTURE: Small Farmers Lead Way in Preserving Soil

By Stephen Leahy Reprint | | Print |

Stephen Leahy

TORONTO, Nov 26 2003 (IPS) - Scientists and development experts are starting to recognise that traditional farming practices play a major role in preserving tropical soils – the world’s richest – which in turn enhances food security.

Scientists and development experts are starting to recognise that traditional farming practices play a major role in preserving tropical soils – the world’s richest – which in turn enhances food security.

Depending on soil type, local conditions and farming methods, soils can be depleted or eroded in just a few years time, says Michael Stocking, a professor in the School of Development Studies at the University of East Anglia in England.

But traditional farming practices like multiple cropping – planting several different food crops in the same field – are very good ways to preserve soil quality and ensure food security, Stocking told IPS after his research on the topic was published in last week’s ‘Science’ magazine.

Multiple cropping, as opposed to monoculture, is a more risk adverse approach – when farmers plant a variety of crops, if the weather is bad for one it will likely be good for another.

That approach can provide subsistence needs and a variety of foods that can also be sold.

In most agricultural regions of the South, crop yields are firmly linked to soil quality, Stocking wrote in his article. Efforts to improve declining trends in food security ought to be focused on local solutions that help farmers help themselves, he concluded.

On Tuesday the United Nations Food and Agriculture Organisation (FAO) reported that the number of chronically hungry people worldwide rose to 842 million in 2000, and is increasing at a rate of five million more people per year.

Meeting the U.N. millennium goal of reducing by half the number of malnourished people by 2015 is becoming “increasingly remote”, concluded the FAO. While the world has enough food, access to it is limited by poverty and shortages of land and water.

Stocking says he supports local solutions because small farmers develop various techniques to minimise risk, including maintaining soil quality for future years.

Professional agronomists trained in the North often discount these approaches because the yields for individual crops are quite low by comparison.

But yield is a poor yardstick for food security, Stocking observes.

North American and European soils have been badly depleted over the past two centuries, and remain highly productive only because of the massive amounts of chemical fertilizer that is applied to them.

“The soils here are just a passive medium keeping the plants upright,” says Stocking.

Agricultural productivity in the North is wholly dependent on the incredibly low-cost energy used to make fertilizers and to power machinery, he adds.

By contrast, with little or no outside inputs, farming systems in the South are much more sustainable.

In Ghana for example, farmers plant up to 54 different varieties of climbing yams inside the forest to protect the vegetables. At the same time, the forest keeps the soils moist and rich in carbon matter.

The story of Chile’s Carlos Crovetto Lamarca is becoming better known. Crovetto inherited an eroded farm along the steep coastal slopes in central Chile in 1953. It was little more than rocks and a series of 20-m deep gullies.

Crovetto went looking for help and was fortunate to receive training in soil and water conservation at the University of California.

He took that knowledge and developed his own system for building soil based on getting rid of his plough and adopting a no-tillage philosophy.

The plough is replaced by the gentler tillage of plant roots, Crovetto says. With crop residues protecting the soil surface from the impact of raindrops, the structure of the soil begins to reform.

Rather than burning or ploughing, a common practice in the North and South, the farmer spreads straw or other crop stubble over the soil.

“I sell the grain today, and I preserve the stubble so I can harvest tomorrow,” he says.

It took a long time but now, after nearly 30 years, Crovetto has created over 30 mms of organic topsoil. That happened at least 20 times faster than if it had been made by the natural process of weathering rocks.

The Chilean’s soil is so rich that his crop yields are as good as any in the North. Best of all, his soils are getting better each year.

Crovetto now teaches his methods to farmers in North America and Europe.

“He has had a tremendous impact on U.S. farmers,” says Don Reicosky, a soil scientist at the U.S. Department of Agriculture’s North Central Soil Conservation Research Lab in Morris, Minnesota.

Improving soil quality has also become the focus of a number of development efforts, such as the Tropical Soil Biology and Fertility Institute (TSBF) of the ‘Centro Internacional de Agricultura Tropical’, based in Nairobi, Kenya.

Created last year, the Institute has a mandate to enhance farmers’ own efforts to protect and improve their soils.

Scientists at the Institute believe that only by raising soil fertility will the 85 percent of Africa’s poor who live in rural areas be able to achieve food security and increase farm incomes.

For farmers like Crovetto, the importance of protecting and improving soil is clear – “we depend daily on the most valuable resource, the soil”.

However, farmers cannot maintain their soil in areas affected by civil conflict, crop export policies and lack of long-term land ownership, says Stocking.

Stability and balancing traditional and modern techniques and knowledge offers the ideal approach to improving food security in the South, he concludes.