Lixia Wang1, Yingxin Li2, Shiv O Prasher3, Baixing Yan1, Yang Ou4, Hu Cui2, Yanru Cui5. 1. Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China. 2. Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China; University of Chinese Academy of Sciences, Beijing 100109, PR China. 3. Bioresource Engineering Department, Macdonald Campus, McGill University, Sainte-Anne- de-Bellevue, QC H9X 3V9, Canada. 4. Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China. Electronic address: ouyang@iga.ac.cn. 5. Institute of Rural Energy and Ecology, Jilin Academy of Agricultural Sciences, Changchun 130033, PR China.
Abstract
The status of heavy metals and the P fractions in compost affects their environmental risk. The present study investigated the effects of different initial carbon to nitrogen (C/N) ratios (15, 22, 27) on redistribution of Cu, Zn, and P fractions during composting. The results showed that the composting process transformed Cu, Zn and P from mobile fractions to more stable fractions. Compost with an initial C/N of 22 showed the most effective immobilization of Cu, Zn and P because of yielding greatest degree of polymerization. Multivariate statistical analysis identified organic matter as the most critical factor for explaining the redistribution of Cu, Zn, and P fractions in composting. However, the degree of organic matter degradation (organic matter content and Humic acid/Fulvic acid) better explained the change of bioavailability factor for Cu and the mobility of P during composting. This research provided guidance for providing technology to reduce environmental risk in compost.
The status of heavy metals and the P fractions in n>an class="Chemical">compost affects their environmental risk. The present study investigated the effects of different initial carbon to nitrogen (C/N) ratios (15, 22, 27) on redistribution of Cu, Zn, and P fractions during composting. The results showed that the composting process transformed Cu, Zn and P from mobile fractions to more stable fractions. Compost with an initial C/N of 22 showed the most effective immobilization of Cu, Zn and P because of yielding greatest degree of polymerization. Multivariate statistical analysis identified organic matter as the most critical factor for explaining the redistribution of Cu, Zn, and P fractions in composting. However, the degree of organic matter degradation (organic mattercontent and Humic acid/Fulvic acid) better explained the change of bioavailability factor for Cu and the mobility of P during composting. This research provided guidance for providing technology to reduce environmental risk in compost.