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[Display omitted] • Regulating pH and inoculating P. chrysosporium increased HS by 81.98% than T1. • Improved transformation of POL and AA accelerated humification process in T4. • Regulating pH at cooling stage helped to the colonization of P. chrysosporium. • P. chrysosporium inoculation improved fungal communities and microbial interactions. • Phanerochaete and Thermomyces as key taxa were enriched in T4 for HA formation. This study aimed to explore the effect of regulating pH and Phanerochaete chrysosporium inoculation at the cooling stage of composting on the lignocellulose degradation, humification process and related precursors as well as fungal community for secondary fermentation. Results showed that composting with P. chrysosporium inoculation and pH regulation (T4) had 58% cellulose decomposition, 73% lignin degradation and improved enzyme activities for lignin decomposition. There was 81.98% increase of humic substance content and more transformation of polyphenols and amino acids in T4 compared to control. Inoculating P. chrysosporium affected the fungal community diversity, and regulating pH helped to increase the colonization of P. chrysosporium. Network analysis showed that the network complexity and synergy between microorganisms was improved in T4. Correlation and Random Forest analysis suggested that enriched Phanerochaete and Thermomyces in the mature stage of T4 were key taxa for lignocellulose degradation, and humic acid formation by accumulating precursors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Urea instead of chicken manure as nitrogen source can significantly reduce the EC value of compost products. • Adding phosphogypsum can reduce the N loss and maintain a suitable C/N ratio in the initial stage of composting. • After adding phosphogypsum (10%∼20%) in the rice husk + urea composting system, the total N loss (85.2%∼89.2%) is similar to the rice husk + chicken manure composting system. • Adding 10%∼20% of phosphogypsum can promote the substrate utilization of rice husk + urea compost product. To explore the effectiveness of urea replacing poultry manure as the nitrogen source in the rice husk composting system, and to promote the utilization of compost products as substrates, 0%, 10%, 20%, and 30% of phosphogypsum were added respectively in the urea composting system, and were compared with the chicken manure composting (RCP0). Finally, the fermentation and maturation of RCP0 were achieved, but high EC value limited the utilization of compost products as the substrate. Urea, as an N source, could lower the EC value, but the C/N ratio was uncoordinated during the initial stage of composting. Adding an appropriate proportion of phosphogypsum could ensure a proper C/N ratio to promote smooth fermentation and enable the products to be ideal substrates. When the added proportion was 30%, the thermophilic stage was shortened significantly but this may increase heavy metals. 10%-20% were concluded to be the recommended proportion. [ABSTRACT FROM AUTHOR]

• Lignin content was reduced during composting by Phanerochaete chrysosporium. • Inoculation of P. chrysosporium during cooling avoided high temperature. • Inoculation of P. chrysosporium during cooling achieved intensive degradation of lignin. • Inoculation during cooling significantly improved compost humification. To enhance the humification process, Phanerochaete chrysosporium (P. chrysosporium) was inoculated during different fermentation phases of the co-composting of maize straw and canola residue. The humification process was determined by evaluating cellulose and lignin contents and key enzyme activities during composting. Results showed that the cellulose and lignin degradation efficiency and humification degree of compost were significantly enhanced in the treatment that inoculated P. chrysosporium in the cooling period (T2). At the end of composting, compared with that in T1 (no inoculation), the content of cellulose and lignin in T2 decreased significantly by 40.00% and 64.30%, respectively, and compared with that in T1 and T3 (inoculation in the initial stage of composting) the content of humus in T2 increased significantly by 55.40% and 75.20%, respectively. This study confirms that inoculating P. chrysosporium during the cooling period promoted the degradation of cellulose and lignin, and therefore enhanced the compost humification. [ABSTRACT FROM AUTHOR]

• The performance and odor issue were clarified in full-scale windrow and trough composting. • Windrow composting was more susceptible to high relative air humidity. • High relative air humidity retarded windrow composting process, no effect on H 2 S emission. • Trough composting was recommended in the areas with high relative air humidity. To comprehensively investigate the effect of different air humidity conditions on the performance and odor emission in composting technology, a full-scale experiment was conducted simultaneously in the regions with low air relative humidity (Kunming) and high relative air humidity (Xishuangbanna), Yunnan province. The results showed that: In the regions with low relative air humidity, similar performances were found on organic matter degradation and germination index values in windrow and trough composting. Windrow composting got lower H 2 S emission, but higher NH 3 release comparing with trough composting. Windrow composting was more susceptible to high relative air humidity. The degradation rate and germination index were 22% and 28% lower than those in trough composting. Therefore, the trough composting was recommended in the areas with high relative air humidity, while suitable NH 3 mitigation measure should be considered. [ABSTRACT FROM AUTHOR]