Effects of the Manure Type on the Evolution of Its Co-Composting With Plant Residues and on the Agronomic Quality of the Compost Obtained

Abstract

During the last decades, there has been an increase in population, with increased food production, and a concentration of inhabitants in cities. This fact has led to an increase in the generation of organic waste of urban, agricultural and livestock origin, which requires adequate management that allows the recycling of the waste generated. In this sense, composting can be a feasible treatment to recycle this waste, and, therefore, improve its properties for agricultural use. Thus, the objective of this study was to evaluate the effect of the type of manure during its co-composting with organic waste of municipal and agricultural origin from the northwest of the island of Gran Canaria, for the subsequent use of the compost obtained as organic amendment in soils or as a substrate for soilless cultivation. For this, three types of manure were used: chicken manure, goat manure and cow manure, which were subjected to a co-composting process mixing them with plant residues from municipal gardens and agricultural crop residues, in the following proportions (on fresh weight): 37.6% straw + 32.7% manure + 29.7% pruning. The composting system used was an open dynamic system of overturned rows, forming three trapezoidal piles 1.5 meters high ´ 2.5 meters wide and 16 meters long. During the composting process, the evolution of temperature, humidity and different physical-chemical and chemical parameters were studied, and the agricultural value, sanitation and maturity of the compost obtained were also evaluated. The results obtained showed that the three piles achieved adequate sanitation according to the thermal requirements established in the regulations (temperature ≥ 60°C for at least 7 days) and a final product or compost suitable for agricultural use was obtained. Key words: organic waste, compost, degradation of organic matter, agricultural quality, sanitation