Effects of organic composts on soil properties: Comparative evaluation of source-separated and non source-separated composts

Abstract

Soil recycling of urban wastes is revealing as a valuable alternative for its disposal. The quality of the compost from these wastes is a key aspect to reduce environmental hazards. Two composts from municipal solid wastes (MSW): a) a source separated compost from Barcelona (CB), and b) non source-separated compost from Murcia (CM), were evaluated with regard to its use as soil amendment. The study was carried out in experimental plots located in the Murcia Region. The composts were added into the top 20 cm of the soil at two doses: 15 and 25 kg m-2 dry weight. Both composts led to significant improvements in physical, biological and fertility soil properties. However, whereas CB did not show significant changes in the soil heavy metal concentration, the CM led to an increase in soil pollution by heavy metal. The soil salinization also was double with CM treatment. In conclusion, the use of source-separated MSW compost as soil amendment seems an environmentally friendly option. The source separation of MSW was very effective to reduce soil pollution hazards.