2. Methods
2.1. Description of raw materials
A mixture of poultry manure and barley straw was used for the composting experiments. The poultry manure, bedding-free material, was collected directly from the conveyor belts located under the poultry cages in a commercial poultry farm located in Murcia (Spain). The barley straw was acquired from a conventional barley crop in Elche (Alicante, Spain). The biochar (particle size