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Sustainable crops for farmers in the Sertão, Brazil

04.09.2006
The Sertão is the hinterland of the Nordeste region. It is semi-arid, and has traditionally been a zone of extensive animal production. However, some thirty years ago, population growth reduced land availability and necessitated a switch to more intensive production systems. The State opted to promote the Green Revolution. However, due to the difficulty of taking account of the climatic and thus economic risks, the operation was a failure.

In the hope of rectifying matters, controlled, or so-called "agroecological", modernization was launched a decade ago. It is based on the assumption that systems can be made more productive by changing farming practices. In particular, the idea is to make better use of the available water, soils and biodiversity so as to produce more biomass.

The aim is also to manage biomass more efficiently, so as both to feed ever-larger numbers of animals and ensure that minerals and organic matter are returned to the soil and thus to crops. The need now is to judge the efficacy of these new practices. What indicators should be chosen with a view to sustainable development?

To answer that question, researchers at CIRAD and EMBRAPA suggested a methodology for establishing indicators of production system sustainability. It comprised three stages: establishing a conceptual framework, padding out that framework with field surveys, and comparing the suggested indicators with those put forward by farmers, to ensure their relevance.

The first two stages resulted in a set of eight indicators: changes in the area of native vegetation, mineral balance, production revenues and costs, fodder balance, the proportion of the fodder balance drawn from outside the farm, changes in animal numbers, changes in security areas and diversification of sources of agricultural income. They resulted from a conceptual framework based on three tenets. Firstly, the production areas and biomass flows within the farm were characterized so as to understand and assess the farmer's production strategy. Farming practices are geared towards producing and managing biomass flows.

It is those flows that change a farm's resource status from an initial situation at the start of the farming season to a final situation at the end. For instance, harvesting fodder crops reduces the mineral reserves in a plot at the end of the season and increases fodder supplies at farm level. These changes are quantifiable and can be expressed as a balance. The proposed indicators thus correspond to end-of-season balances of the farm's resource status.

The researchers then talked to farmers. For farmers, a farm is sustainable if it enables them to feed their family and animals. It is difficult for them to identify the problems on their farm. In general, they put them down to climatic conditions alone. They also have trouble ranking criteria that are in fact interrelated and are often just different ways of qualifying the same thing. The criteria established by farmers, such as obtaining larger areas of land, improving their profits or increasing herd size, all belonged to the list established by the researchers. They also reflect aspects that were not in the list of criteria, such as labour constraints, which suggested it would be wise to include an assessment of the "labour" resource in the analysis.

Such an approach enables farmers to understand how their farming systems function, by placing their sustainability criteria in a grid that includes biomass flows and resource balances. It enables them to rank their problems and identify the real difficulties they face. The indicators have now been applied to around ten farms. In particular, the results have led farmers to rethink the fodder supply and demand balance. They have also prompted them to think about how they might diversify their supply. The analysis framework is thus a way of helping farmers think about their practices and the possibilities of changing them.

This study has already contributed to a change in practices among the farmers who took part. The next step is to validate the sustainability indicators by taking account of the parameters that are missing: the labour resource, which is a major production factor, and water resource flows.

Helen Burford | alfa
Further information:
http://www.cirad.fr/en/actualite/communique.php?id=518

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