Nutrient Management and Farmers' Concept of Soil Fertility and Fertilisers: A Case Study in Southern Vietnam

Nutrient management in Vietnam was exposed to major changes with the introduction of the reform policy (‘doi moi’), which entailed the introduction of new crops and new fertilisers and increased consumption of mineral fertilisers, leading to higher yields but also possibly to higher losses of nutrients to the environment. However, sustainable nutrient management options can be developed through merging scientific and local concepts. Participatory methods were used to gather information about the farmers' concept of soil fertility, the fertilisers available and their features, and the information available. The farmers' concept of soil fertility was more directly connected to the ability of the whole system to promote good yields than the scientific concept of soil fertility as the soil's ability to deliver sufficient nutrients and water to the plant. The farmers' concept of fertilisers included a wide range of amendments that were added to promote good conditions for plant growth, rather than to provide nutrients for the crop. The study revealed an information system whereby some innovative farmers were the keys to other farmers' access to external information on nutrient management. The results show that any attempt made by outsiders to improve nutrient use efficiency must be applicable to the farmers' concepts.