Shuyan Li1, Danyang Li1, Jijin Li2, Guoxue Li3, Bangxi Zhang4. 1. Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China. 2. Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China. 3. Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China. Electronic address: ligx@cau.edu.cn. 4. Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China; Guizhou Institute of Soil and Fertilizer, Guiyang 550006, China.
Abstract
Sewage sludge and corn stalk were co-composted under different aeration rates 0.12 (AR0.12), 0.24 (AR0.24), 0.36 (AR0.36)L·kg-1DMmin-1, respectively. Transformation of humic substance was evaluated by a series of chemical and spectroscopic methods to reveal compost humification. Results showed that aeration rate could significantly affect compost stability and humification process. Humic acid contents in AR0.24 were significantly higher than those in the other two treatments. The final humic acid/fulvic acid ratios in AR0.12, AR0.24 and AR0.36 treatment were 1.0, 1.9 and 0.8, respectively, corresponding to the final E4/E6 of 4.7, 3.2 and 5.5. Moreover, compost in AR0.24 treatment had a high stability degree due to the low C/N atom ratio and high C/H atom ratio. However, it is noteworthy that composting could not significantly affect the structure of HA in a 35-day period. These results indicate that composting with the aeration rate of 0.24L·kg-1DMmin-1 could accelerated the humification process.
Sewage sludge and corn stalk were co-composted under different aeration rates 0.12 (n class="Chemical">AR0.12), 0.24 (AR0.24), 0.36 (AR0.36)L·kg-1DMmin-1, respectively. Transformation of humic substance was evaluated by a series of chemical and spectroscopic methods to reveal compost humification. Results showed that aeration rate could significantly affect compost stability and humification process. Humic acid contents in AR0.24 were significantly higher than those in the other two treatments. The final humic acid/fulvic acid ratios in AR0.12, AR0.24 and AR0.36 treatment were 1.0, 1.9 and 0.8, respectively, corresponding to the final E4/E6 of 4.7, 3.2 and 5.5. Moreover, compost in AR0.24 treatment had a high stability degree due to the low C/N atom ratio and high C/H atom ratio. However, it is noteworthy that composting could not significantly affect the structure of HA in a 35-day period. These results indicate that composting with the aeration rate of 0.24L·kg-1DMmin-1 could accelerated the humification process.