Uruguayan market gardeners welcome soil improvement

Market gardeners in Uruguay are able to prevent soil degradation on their plots by improving the way they manage their organic matter. PhD student Florencia Alliaume, in the Farming Systems Ecology group, concludes that the use of animal manure, green fertilizers and crop residues leads to an increase in carbon compounds in the soil. In Uruguay, market gardening is exhausting the soil. Intensively farmed plots contain 36 percent less organic carbon compounds by weight than fields that have been left unused for a long while, according to Alliaume’s measurements. The soil structure was also poorer and the soil retained 11 percent less water; these are all signs of soil degradation. Alliaume tested an ecological soil management system whereby the market gardeners bought manure from local chicken farmers, ploughed in more crop waste and used green fertilizers as much as possible. This led to the organic content increasing again by about 10 percent over a period of five years. ‘This means you can reverse some of the soil degradation over a brief period, even in intensive market garden businesses,’ says research supervisor Walter Rossing. Apparently, the market gardeners are enthusiastic about the project. ‘It is the first time that they have had an overall view of the carbon and minerals cycle for an individual farm.’