Effects of turning frequency on the nutrients of Camellia oleifera shell co-compost with goat dung and evaluation of co-compost maturity

Abstract

Composting is an important treatment method for Camellia oleifera shell and goat dung, which is crucial for the development of tea oil industry and goat breeding industry. Ventilation is the important regulatory factor in composting process, and high degree of maturity is the principal requirement for safe application of composting product. In the study, four treatments were designed as every 5 days turning (A1), every 7 days turning (A2), every 10 days turning(A3), and every 15 days turning (A4) for evaluating the maturity of Camellia oleifera shell co-composted with goat dung and optimizing turning frequency. During composting, TN, NO 3 N, GI, Solvita maturity index was increased along with composting process, while NHþ4 N, C/N shown an opposite trend. For all treatments, the longest thermophilic period (over 50C), highest total nutrient and lowest C/N ratio were observed in A2. A turning frequency of every 7 days for co-compost of Camellia oleifera shell and goat dung could enhance the composting product quality. According to the analysis of spearman correlation, TN, C/N ratio, and GI could be used to comprehensively evaluate the compost maturity.