Quality evaluation of livestock and poultry manure in black soil area of Songnen Plain

Clarifying the quality differences of livestock and poultry manure in black soil area of Songnen Plain, Heilongjiang Province, can provide theoretical basis for its quality improvement and rational application. In this study, 67 compost samples of pig manure, cattle manure, sheep manure and chicken manure were collected from the black soil area of Songnen Plain, Heilongjiang Province. By measuring the technical indexes, limit indexes and organic components of different livestock manure, a comprehensive score model was established to evaluate the quality of livestock manure. The results show that: (1) The average seed germination index (GI) of pig manure, cattle manure, sheep manure and chicken manure are 44.1%, 57.0%, 51.9% and 41.4%, respectively, which is close to or greater than 50% of livestock manure harmless requirements, but lower than 70% of organic manure NY/T525-2021 standard requirements; (2) Among the four kinds of livestock and poultry manure, all indexes of cattle manure are closer to the requirements of NY/T525-2021 standard, and the contents of soluble organic matter (DOM), extractable humic acid (HE), humic acid (HA) and fulvic acid (FA) in cattle manure are higher than those of the other three kinds; (3) In the comprehensive score model of livestock and poultry manure quality evaluation, cattle manure is with the highest score of 0.834, and the scores of other manures are 0.761 sheep manure, 0.732 pig manure and 0.508 chicken manure. Overall, the maturity of the four kinds of livestock and poultry manure still needs to be further improved, and its comprehensive quality is in the order of cattle manure > sheep manure > pig manure > chicken manure.