Sunday, September 27, 2009

'No-till' farming the answer?

Worldwide, there are 923 million people who go hungry. The FAO estimates that 75 million of those are suffering as a result of high food prices. In Sub-Saharan Africa alone, the number of people who cannot afford to eat is 24 million.

While food costs continue to spiral, the environmental cost of growing food is also mounting as the world struggles with another less tangible but far more imminent challenge to food security. All across the region of Southern Africa, the effects of climate change are already being felt as droughts intensify, rainfall patterns shift and biodiversity is lost as agricultural refugees seek out new potential farm land. In a region that is classified as arid and is already grappling with the challenges of conflict or political instability or a lack of skills among new emerging farmers, food security in these developing countries is under severe threat.

As food prices climb, it is imperative that agricultural output of these developing nations does not fall further so as to make them net importers of food and add to the already high cost burden of meeting development needs. While emergency food aid has its place in so far as addressing a short term crisis, it remains an expensive and unsustainable intervention.

With virtually no resources available to these regions for increased spending on infrastructure, mechanical equipment, pesticides or fertilizers, a grassroots approach that draws on the available capacity and resources of local communities is needed.

The UN's agency for food and agriculture is advocating a return to traditional farming techniques. Could Conservation agriculture be the answer?

Conservation agriculture (CA) is not a new concept to farming. It is governed by three major principles which have been employed in small scale subsistence or permaculture for centuries that calls for farming in harmony with nature.

1. No-tillage
Mechanical disturbance of the soil has not only shown to increase soil erosion and water runoff, but also to inhibit the natural activity of micro-organisms in the soil – essential for strengthening the soil profile.

In Southern Africa, where the agricultural workforce is facing a deepening health crisis as a result of HIV / Aids, the no-tillage approach means less energy and labour can be spent preparing the soil and more time planting and reaping. In rural areas, where communities are experiencing a demographic collapse as the men abandon their post as head of household to seek migrant labour in cities, women and in particularly the elderly have been left to tend to community food gardens.

The overwhelming environmental benefits of no-tillage as has begun to be practiced around the world showed a reduction in greenhouse gas emissions of 10 million metric tons in 2004 and 14.8 million metric tons in 2006 as tractors and fuel were set aside in favour of the no-tillage approach.

2. Mulching
Covering the soil with organic plant matter has shown to not only protect the soil from exposure to the elements but also to slow down evaporation of water and rainfall.
As the organic matter breaks down it returns nutrients to the soil and stimulates micro-organism activity, so reducing the need for costly fertilizers. Working hand in hand with the no-tillage approach, planting is implemented through the soil cover, further reducing labour and time costs.

3. Crop-rotation
As is the key to the success of biodiversity in nature, diversity in cropping is imperative to reducing soil degradation and maintaining the natural balance of potential pests.
Crop homogenisation over large tracts of land has shown to strengthen certain pests that have had time to adapt and strengthen to its surroundings.
In regions such as China or the United States, where rice or maize and wheat have replaced crop diversity with homogenised fields, a single disease could trigger a food crisis of epic proportion.

In East Africa, where forests were cleared to make way for coffee planting, the coffee borer beetle has had a devastating impact on the coffee crops of Kenya and Tanzania. Farmers are since returning to shade-grown coffee where natural predators like birds are re-introduced through the preservation of forest habitat.
Employing crop-rotation and cross planting techniques encourages natural predators and reduces the need for herbicides and pesticides that ultimately damage natural resources.
As ground water quality comes under increasing pressure from drought and contamination from human settlements, conservation agriculture has the potential to halt the demise of one of our most precious and shrinking resources that until now has been subjected to contamination from leeched chemicals.

Conservation Agriculture seems to be what communities are practicing already with permaculture and small scale agriculture, but is this method really able to work for commercial scale farming?