Comparing compost from urban waste and digested organic matter as fertilizer for production of corn (Zea mays L.)

The use of compost from urban waste can represent a sustainable way to replace mineral fertilizers for cultivation of corn (Zea mays L.). A 1-year experiment was conducted in an irrigated lowland farm in a nitrogen-vulnerable zone of Marche Region (central Italy). The aim of the research was to compare the effect of compost from urban waste, mineral fertilizer and digested organic matter (from corn through solid-state anaerobic digestion) on corn production, soil fertility and quality. A completely randomized block design with three replicates was used and 100 kg nitrogen ha(-1) for each treatment was provided during sowing. Yield components at harvest were measured. Nutrients and heavy metal content in the soil were registered before and after the experiment. Compost had positive effects on corn yield: significant differences between compost and digested organic matter were highlighted in the production (in terms of grain and biomass), whereas similar production was obtained using mineral fertilization. Significant differences were also detected between digested organic matter and mineral fertilization (higher grain and biomass production). Furthermore, both compost and digested organic matter brought macro-and micronutrients to the soil and did not increase heavy metal content. In conclusion, compost from urban waste represents an alternative way of fertilization in agriculture, comparable to mineral nutrition but with higher sustainability. Further perennial experiments are required to study the use of anaerobic-digested organic matter and the accumulation of organic matter and heavy metals in the soil.