REVIEW OF THE USE OF SWINE MANURE IN CROP PRODUCTION: EFFECTS ON YIELD AND COMPOSITION AND ON SOIL AND WATER QUALITY

The world swine population produces about 1.7 billion tonnes of liquid manure annually. At an application rate of 20 tonnes per hectare, this could fertilize about 85 million hectares of land annually. Storage and disposal of this material presents a challenge to producers because of the potential for environmental pollution. However, because swine manure contains essential plant nutrients, use of swine manure as a soil amendment for crop production is a practical method to solve the disposal problem. The composition and effectiveness of swine manure as a source of plant nutrients depends on several factors including type of ration fed, housing system, method of manure collection, storage and handling. Research has shown that manure application increased soil N, P, K, Ca, Mg and Na. However, heavy or excessive application of manure increased leaching of NO₃-N, P and Mg. Swine manure is reported to be effective in increasing the yields of cereals, legumes, oilseeds, vegetables and pastures, and in increasing plant nutrient concentration, especially N, P and K. The efficient use of swine manure can be an agronomically and economically viable management practice for sustainable crop production in temperate regions such as the Canadian prairies where the swine industry is expanding rapidly.