Rotating crops with vetch and fallow, together with returning the straw to the soil after the harvest, increases the production yield two-fold in comparison to conventional methods of crop growing that use chemical additives and herbicides, said Gabriel Pardo Sanclemente at the University of Navarre in Spain.
He claims that the profitability of this ecological system can even be multiplied by four when an ecological market exists. Ecological systems of production of cereals are based on the rotation of crops, the use of natural organic additives and the mechanical control of weeds, in order to maintain the fertility of the soil and weeds in the long term and at reasonable levels.
Pardo Sanclemente specifically investigated the viability of ecological systems of production of cereals in semi-arid land, a viability that depends on the yield of quality crops free from agrochemical waste products and for which a higher price can be paid, and so up gross profit margin of the crop yields and consequently, an agriculture more respectful of the environment is achieved, said the researcher.
Experiments were carried out comparing chemical methods of fertilisation and weeding using with the method - recognised by the Regulations on Ecological Agriculture. The study centred on the results from 26 tests carried out in various semi-arid land zones in Spain and on which barley, using vetch as green fertiliser, was rotated with wheat and fallow.
Results found that the 'greatest profitability' was obtained from the ecological system - organic fertilisation and the mechanical control of weeds. Following this was the 'minimum system', without fertilisation methods or the mechanical control of weeds. Trailing behind and presenting the worst results in terms of profitability was the 'conventional system'.
Pardo Sanclemente favoured the 'minimum system' for crop growing because it does not significantly diminish production but reduces costs, and so increases profitability.