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The effect of peach shell biochar (PSB) amendment on sheep manure (SM) composting was investigated. Five different ratios of PSB were applied (0%, 2.5%, 5%, 7.5%, and 10% PSB), and named T1 to T5, and run 50 days of composting experiment. It was found that PSB (especially 7.5% and 10%) could improve the compost environment, regulate the activity of microorganisms and related enzymes, and promote the decomposition of compost. 7.5% and 10% PSB advanced the heap into the thermophilic stage and increased the maximum temperature, while also increasing the germination index by 1.40 and 1.39 times compared to control. Importantly, 10% PSB effectively retained more than 60% of carbon and 55% of nitrogen by inhibiting the excess release of NH 3 and greenhouse gases. High proportion PSB amendment increased the activity of dehydrogenase and cellulase, but inhibited protease and urease. The correlation results indicated that PSB changed the key bacterial genus, and there was a stronger association with environmental factors at 7.5% and 10%. Therefore, 7.5% and 10% peach shell biochar can be used as appropriate proportions to improve composting conditions. [Display omitted] • Peach shell biochar enhanced the temperature of thermophilic period. • The germination index of biochar modified group was 1.14–1.40 times than control. • Peach shell biochar reduced NH 3 and greenhouse gas emissions during composting. • 10% biochar increased dehydrogenase and cellulase activities. [ABSTRACT FROM AUTHOR]

Total livestock emissions account for up to 14.5% of man-made greenhouse gas emissions. Counteractive measures, such as circular economy concepts and negative emission technologies are necessary to limit global warming below 1.5 °C. Possible treatment options for organic manure include anaerobic digestion, combustion, gasification, hydrothermal liquefaction and composting. The choice of treatment varies depending on the economics, the requirement of a specific product, and sociocultural factors. Commercialization of these treatments needs a blend of appropriate technology, feasible economics, policy support and agreeable socio-cultural conditions. Key findings of this study include the following: 1. Increasing scientific awareness about manure management and treatment; 2. Building a sustainable cooperative model to commercialize technologies; 3. Creating a market for manure recycling products; 4. The role of policy in supporting technologies and consumers; and 5. The codigestion of substrates for better efficacy. Current trends show minimal actions in place as opposed to the high-rate of acceleration that is necessary. • Improper disposal of organic manure could cause unwanted ecological damage. • Recent biorefinery models to recover energy and nutrients are addressed. • Biological treatment of organic manure remains the predominant recycling approach. • Limited knowledge of the potential of biorefinery approaches still exist. • Successful implementation of biorefineries requires policy and social support. [ABSTRACT FROM AUTHOR]

• Addition of peach shell biochar with microbial agents decreased the CO 2 and CH 4 emissions. • The additives effectively accelerated the humification process. • The values of germination index and humic/fulvic acids ratio were 1.12 ∼ 1.36 and 1.13 ∼ 2.43 times greater than control. • 10% peach shell biochar increased 3.20%∼67.15% Ascomycota related to lignocellulose degradation. • 10% peach shell biochar has significant correlations physic-chemical properties and fungal community. In this study, explored the influence of different proportion (0%, 2.5%, 5%, 7.5%, and 10%) peach shell biochar (PSB) with microbial agents (EM) on the carbon transformation, humification process and fungal community dynamics during sheep manure (SM) composting. And no additives were used as control. The results manifested that the CO 2 and CH 4 emissions were effectively reduced 8.23%∼13.10% and 17.92%∼33.71%. The degradation rate of fulvic acid increased by 17.12%∼23.08% and the humic acid contents were enhanced by 27.27%∼33.97% so that accelerated the composting. Besides, the dominant fungal phylum was Ascomycota (31.43%∼52.54%), Basidiomycota (3.12%∼13.85%), Mucoromycota (0.40%∼7.61%) and Mortierellomycota (0.97%∼2.39%). Pearson correlation analysis and network indicated that there were different correlations between physicochemical indexes and fungal community under different additive concentrations. In brief, the two modifiers application promoted the SM degradation and affected the fungal community structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Addition of peach shell biochar and microbial agent increased the temperature and pH. • Both additives decreased the emissions of NH 3 and N 2 O and reduced nitrogen loss. • NO 3 −-N and TKN increased by 0.02–0.11 g/kg and 8.15–9.13 g/kg compared to control. • Both additives increased the bacteria abundance related to C and N conversion. • Both additives were reduced the abundance of denitrifying bacteria (Luteimonas). In this study, the effects of peach shell biochar (PSB) and microbial agent (EM) amendment on nitrogen conservation and bacterial dynamics during sheep manure (SM) composting were examined. Six treatments were performed including T1 (control with no addition), T2 (EM), T3 (EM + 2.5 %PSB), T4 (EM + 5 %PSB), T5 (EM + 7.5 %PSB), and T6 (EM + 10 %PSB). The results showed that the additives amendment reduced NH 3 emissions by 6.12%∼32.88% and N 2 O emissions by 10.96%∼19.76%, while increased total Kjeldahl nitrogen (TKN) content by 8.15–9.13 g/kg. Meanwhile, Firmicutes were the dominant flora in the thermophilic stages, while Proteobacteria , Actinobacteriota , and Bacteroidota were the dominant flora in the maturation stages. The abundance of Bacteroidota and Actinobacteriota were increased by 17.49%∼32.51% and 2.31%∼12.60%, respectively, which can accelerate the degradable organic materials decomposition. Additionally, redundancy analysis showed that Proteobacteria , Actinobacteriota , and Bacteroidota were positively correlated with NO 3 −-N, TKN, and N 2 O, but a negative correlation with NH 3 and NH 4 +-N. Finally, results confirmed that (EM + 10 %PSB) additives were more effective to reduce nitrogen loss and improve bacterial dynamics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bacterial community was tracked at four stages of biochar driven composting. • Biochar regulates bacterial community primarily acting in the thermophilic stage. • Predominant bacteria from the Proteobacteria shifted into Firmicutes in the thermophilic stage. • The 7.5 and 10% biochar amended composts has more cooperative and complex interactions. Bacterial communities were dynamically tracked at four stages of biochar-driven sheep manure pile composting, and the co-occurrence networks with keystone taxa were established. The succession of bacterial community obvious varied during the composting process, Proteobacteria predominant in initial stage (39%) then shifted into Firmicutes in thermophilic (41%) and mesophilic (27%) stages, finally the maturation stage dominant by Bacteroidota (26%). Visualizations of bacterial co-occurrence networks demonstrate more cooperative mutualism and complex interactions in the thermophilic and mesophilic phases. Noticeably, the 7.5 and 10% biochar amended composts shown highest connections (736 and 663 total links) and positive cooperation (97.37 and 97.13% positive link) as well as higher closeness centrality and betweenness centrality of keystone taxa. Overall, appropriate biochar addition alters bacterial community succession and strengthens connection between keystone taxa and other bacteria, with 7.5 and 10% biochar amended composts has intense mutualistic symbiosis among bacterial communities. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate antibiotic resistant fungal (ARF) communities in pig manure (PM) composting employing two different biochar (coconut shell-CSB and bamboo biochar-BB) as amendment. Three treatments (Control, 10% CSB and 10% BB) were designed and indicated with T1 to T3. Experimental results declared that the fungal abundance significantly reduced among the both biochar applied treatments but three dominant phyla Ascomycota , Basidiomycota and Mucoromycota were still relatively greater abundance present. There were significant differences (p < 0.05) in the relative abundance and diversity of fungi among all three treatments. Interestingly, biochar addition regulated the overall fungal community in final compost. Compared with the control group, the abundance of fungi was positively mobilized, and especially CSB showed a better effect. Conclusively, biochar has potential to inhibit and reduce the ARGs population and mobility in compost. Thus, these findings offer new insight to understand the succession of ARFs during PM composting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Impact of biochar amendment on microbial dynamics and enzymatic activities was studied. • Most enzymatic activity enhanced after biochar amendment in composting feedstock. • Biochar enriched bacterial diversity and decreased fungal diversity. • The most key microbial connectors affiliated to Oligella and Fermentimonas. • More complex correlation between enzyme and bacterial compared to fungal community. Aimed to evaluate the coexistence of bacterial and fungal diversity and their correlation with enzymatic activity in response to biochar. This study performed aerobic composting based on typical agricultural wastes of sheep manure with additive apple tree branch biochar at distinct concentration (0, 2.5, 5, 7.5, 10 and 12.5% corresponding from T1 to T6). The result demonstrated that appropriate amendment of biochar enriched bacterial diversity (1646–1686 OTUs) but interestingly decreased fungal diversity (542–630 OTUs) compared to control (1444 and 682 OTUs). Biochar addition enhanced all enzymatic activities and its correlation with bacterial was more complex than fungal community (786 and 359 connect edges). The dominant microbes comprised of Firmicutes (45.2–35.2%), Proteobacteria (14.0–17.5%), Basidiomycota (32.4–49.5%) and Ascomycota (11.3–37.5%) among all the treatments. Overall, biochar regulates the composting microenvironment by influencing the microbial diversity and associated enzymatic activities. [ABSTRACT FROM AUTHOR]

• Bean dregs (BD) and biochar (B) promote the decomposition and humification of compost. • BD + B influences the structure and function of bacterial communities. • BD + B accelerates organic matter transformation by regulating the pH of the compost. This study researched the impacts of biochar (B) and bean dregs (BD) on organic matter degradation and humification, as well as the bacterial community and functional characteristics during pig manure (PM) composting. The temperature, pH, and dissolved organic carbon (DOC) were reached the maturity of compost. Results indicated that BD + B treatment promoted organic matter degradation and increased humic acid content by 19.5–25.1% from the control (CK). Additionally, the bacterial communities were determined by high-throughput sequencing, and their metabolic functions were evaluated through the phylogenetic investigation of communities by reconstructing unobserved states (PICRUSt). BD + B influenced the microbial community structure of compost, and the PICRUSt results indicated that BD + B strengthened the metabolism of carbohydrates and amino acids. Redundancy analysis (RDA) was conducted, and a positive correlation was observed between organic matter transformation and temperature, pH, DOC, and community structure. Therefore, regulating these compost properties can effectively promote organic matter transformation during composting. [ABSTRACT FROM AUTHOR]

• Relative abundance of bacterial was richer in 6% pig manure biochar composting. • Phylogenetic tree and krona have confirmed the bacterial diversity variation. • Bacterial community had distinctive distribution among all five composts. • Biochar additive affected bacterial metabolism related to organic waste degradation. The influence of pig manure biochar amendment (PMBA) during the pig manure (PM) and wheat straw (WS) composting was evaluated. Five concentration of PMBA (0%, 2%, 4%, 6% and10%) were applied to explore the bacterial distributions in PM compost by 16SDNA amplicons sequencing. The results showed that the addition of 6% PMBA could significantly enhanced the bacterial community abundance compared with other composts, while control has relative less bacterial population (332 OTU). The visualization of phylogenetic tree and krona demonstrated the distinctive distribution of each composts, suggested that biochar dosages have an influence on bacterial communities' variation during co-composting. Beta-diversity of distance matrix heat-map and principal component analysis confirmed that bacterial communities were considerably correlated with increasing PMBA. Redundancy also confirmed the similarity and discrepancy among all treatments and environmental factors. This work considered as the potential of PMBA as a booster in composting, where T4 has most plentiful bacterial community and diversity. [ABSTRACT FROM AUTHOR]

• Biochar and cultures efficiently promote the immobilization of heavy metals. • Biochar and cultures improve process and hygiene quality of composting. • Bacteria richness notably enhanced under apply of biochar and culture. • Proteobacteria (56.22 %) and Bacteroidetes (35.40 %) were dominance phyla. • Biochar + bacteria consortium were showed significant correlation. This study evaluated the effect of integrated bacterial culture and biochar on heavy metal (HM) stabilization and microbial activity during pig manure composting. High-throughput sequencing was carried out on six treatments, namely T1-T6, where T2 was single application of bacteria culture (C), T3 and T5 were supplemented with 12 % wood (WB) and wheat-straw biochar (WSB), respectively, and T4 and T6 had a combination of bacterial consortium mixed with biochar (12 % WB and 12 % WSB, respectively). T1 was used as control for the comparison. The results show that the populations of bacterial phyla were significantly greater in T6 and T4. The predominate phylum were Proteobacteria (56.22 %), Bacteroidetes (35.40 %), and Firmicutes (8.38 %), and the dominant genera were Marinimicrobium (53.14 %), Moheibacter (35.22 %), and Erysipelothrix (5.02 %). Additionally, the correlation analysis revealed the significance of T6, as the interaction of biochar and bacterial culture influenced the HM adsorption efficiency and microbial dynamics during composting. Overall, the integrated bacterial culture and biochar application promoted the immobilization of HMs (Cu and Zn) owing to improved adsorption, and enhanced the abundance and selectivity of the bacterial community to promote degradation and improving the safety and quality of the final compost product. [ABSTRACT FROM AUTHOR]

• Influence of biochar and bacterial inoculum amendment on cow dung composting was studied. • 12% WSB and bacterial consortium (BC) has lowest carbon and nitrogen loss. • 12% WSB and BC has highest bacterial population and degraded efficiency. • 12%WSB + BC amendment is superior option for cow manure composting. • 12%WSB + BC showed strong interrelation between bacterial community and physicochemical factors. The present study evaluates the effectiveness of different types of biochar additives and bacterial inoculation on gaseous emission, nutrient preservation, and relevant functional bacterial community during cow manure composting. The result revealed that biochar and bacterial consortium inoculation effectively inhibited gaseous emission and improved carbon and nitrogen sequestration, remarkably enriching the abundance of the functional bacteria community. Notably, superior efficacy was found in 12% wheat straw biochar and bacterial consortium amendment composting of T6 with the lowest cumulative CO 2 -C and NH 3 -N (308.02 g and 12.71 g, respectively), minimal total C and N losses, and the highest bacterial population. Additionally, gaseous emission exhibited a strong correlation between physicochemical properties with intersection of 66.78% and a unique substrate utilizing bacterial communities. Consequently, the integrated application of biochar and bacterial consortium inoculation was suggested as an efficient method to adjust microbial activity and facilitate cellulose-rich waste degradation, enabling efficient management of organic waste from cow manure and wheat straw by composting. [ABSTRACT FROM AUTHOR]

Clay has a positive influence on organic matter degradation and nitrogen conservation during chicken manure composting, but its effects on the diversity of antibiotic-resistant bacterial are unclear. The impact of the clay amendment (0% (T1), 2% (T2), 4% (T3), 6% (T4), 8% (T5) and 10% (T6) on the environmental risk of antibiotic-resistant bacteria abundance during chicken manure composting was investigated. The results showed that 4% clay increased the relative abundances of antibiotic-resistant bacterial, while 8% and 10% clay additions significantly reduced the total relative abundances of antibiotic-resistant bacterial in the compost, where the relative abundances of antibiotic-resistant bacterial was 0.46 log lower than the control. Clay mainly affects the distribution of antibiotic-resistant bacterial by influencing the relative abundances of Firmicutes , Proteobacteria , Actinobacteria , and Bacteroidetes phylum. The maximum dosage of the clay amendment had a more persistent impact on the antibiotic-resistant bacterial community. However, bacterial abundance could be classified according to the composting time under diverse treatments. In the present study, the abundance of the antibiotic-resistant bacterial has a considerable impact on the alteration of the physicochemical parameters during composting. The correlations between the physicochemical parameters (temperature, carbon/nitrogen ratio, and gaseous emissions) and antibiotic-resistant bacterial were more significant than pH and germination index. Image 10028 • Clay amendment had a synergetic impact on the bacterial community during composting. • Clay addition is important role play to diverse bacterial community. • The abundance of Firmicutes, Proteobacteria and Actinobacteria , are significantly higher. • Composting has better efficacy to reduce the antibiotic resistant bacteria in compost. [ABSTRACT FROM AUTHOR]

• Applied Bean dregs (BD) in pig manure composting generated high quality product. • The total nitrogen content was the highest in 10%BD amended. • 10%BD was the optimum in promoting the diversity and abundance of bacteria. • 10%BD improved the activity of Firmicutes. This work studied the nitrogen transformation and bacterial dynamics in the co-composting of bean dregs (BD) and pig manure (PM). Four treatments were performed with BD at 0% (CK), 5%, 10% and 15% (w/w dry basis of PM) amended for 49-days aerobic compost. Results revealed that the temperature, NH 4 +-N and pH of end product all met the maturity requirement. The BD-amendment increased nitrogen losses (8.55%–55.92%) during composting compared to CK. However, this amendment also enhanced total nitrogen content (TKN) of end products (1.86%–12%). The highest content of TKN was in 10%BD-amended treatment with relatively lower nitrogen loss compared to 15%BD. Furthermore, the results of 16S rDNA showed that BD-amended changed the bacterial community composition compared with CK. Especially, 10%BD-amended was the optimum in promoting the diversity and abundance of bacteria. Additionally, Firmicutes , Actinobacteria, Proteobacteria, Bacteroidetes and Chloroflexi were dominant phyla and Bacilli was dominant class in BD-amended compost. [ABSTRACT FROM AUTHOR]

The purpose of this research was to evaluate the effect of medical stone (MS) on nitrogen conservation and improving the compost quality during the pig manure (PM) composting. Five treatments were designed with different concentrations of MS0%, 2.5%, 5%, 7.5% and 10% (on dry weight of pig manure basis) mixed with initial feed stock and then composted for 60 days. The results showed that MS amendment obviously ( p < 0.05) promoted the organic waste degradation and prolonged the thermophilic phase as well as enhanced the immobilization of heavy metals Cu and Zn. With increasing the amount of MS, the NH 3 loss and N 2 O emission were significantly reduced by 27.9–48.8% and by 46.6–85.3%, respectively. Meanwhile, the MS amendment could reduce the NO 2 − -N formation and increase the NO 3 − -N content. Finally our results suggested that 10%MS addition could significantly reduce the nitrogen conservation as well as improve the quality of compost. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adding 0.5–1.5% allophane promotes 261–350% methane production from chicken manure. • Allophane can alleviate the ammonia inhibition and improve the anaerobic digestion. • The direct interspecies electron transfer (DIET) is intensified by adding allophane. • Allophane increases the relative abundance of Methanosaeta & Methanosarcina in DIET. Synthesized allophane was employed in anaerobic digestion of chicken manure to improve the stability and methane production under ammonia inhibition. Adding 0.5 %, 1.0 % and 1.5 % (w/w) allophane increased the methane production by 261 ∼ 350 % compared with the group without allophane addition. Further investigation indicated that the maximum adsorption capacity of allophane for NH 4 +-N achieved at 261.9 mg/g; it suggested that allophane adsorption potentially alleviated the ammonia inhibition, which also was reflected by the increase in the activity of the related enzyme, such as coenzyme F 420. Moreover, allophane addition also intensified the direct interspecies electron transfer (DIET) in anaerobic digestion; it can be well supported by the increased relative abundance of Methanosaeta and Methanosarcina involved in the DIET. Overall, the improved anaerobic digestion via alleviating ammonia inhibition and intensifying DIET by allophane was elucidated comprehensively, which can contribute to the development of a functional additive for efficient anaerobic digestion in practical application. [ABSTRACT FROM AUTHOR]

Aiming to provide a highly-valuable green fertilizer, the effects of tertiary-amine bentonite on the carbon transformation and global warming potential were investigated during composting. TAB in weight ratios of 0%, 2%, 4%, 6%, 8% and 10% was mixed with CM and WS and composted for 50 days, respectively. The results showed that adding TAB promoted the degradation of TOC and DOC. With an increase in TAB amounts, HA content and polymerization were elevated by 11.71–27.08% and 3.40–47.00%, which was also supported by investigation of spectral parameters including SUVA 254 , SUVA 280 , A 4 /A 1 , and A 363-500. TAB benefited the CO 2 emission while reducing the volatilization of CH 4 and N 2 O, and the lowest global warming potential value was 108.99 in the 10% TAB treatment. TAB is considered as an economic amendment for improving CM composting process and quality in suggested amounts of 4%–10% based on humic-substance variations, spectral profiles of DOC, and global warming potential as well as the natural characterizations of TAB. Image 102 • Tertiary-amine bentonite (TAB) could promote the degradation of organic carbon. • The TAB could improve organic matter humification as well as compost maturity. • The TAB addition promoted aromatization by spectral parameters analysis. • The treatment with 10% TAB had a lowest value on greenhouse gas equivalent. [ABSTRACT FROM AUTHOR]

• Assessment of biochar amendment benefits on microbial community were studied. • Coconut shell biochar and bamboo biochar bring changes to bacterial communities. • Mitigating threat of antibiotic has been solved by antibiotic resistant bacteria. • Proteobacteria, Actinobacteria, Bacteroidetes are 3 phyla with richer abundance. • Bacterial communities are conspicuously regulated by environmental factors. The study aim was to reveal the mechanism of impact of two type biochar on composting of hen manure (HM) and wheat straw (WS). Biochar derived from coconut shell and bamboo used as additives to reduce antibiotic resistant bacteria (ARB) in HM compost. The results manifested that effect of biochar amendment was significant to reduce ARB in HM composting. Compared with control, the microbial activity and abundance were increased in both biochar applied treatment, and bacterial community was changed. Additionally, network analysis revealed that biochar amendment increased the quantity of microorganisms related to organic matter degrading. Among them, coconut shell biochar (CSB) played a pioneering role to mitigate ARB to better exert its effects. Structural correlation analysis showed that CSB reduce ARB mobility and promote organic matter degradation via improving beneficial bacterial community structure. Overall, composting with participation of biochar amendment stimulated antibiotic resistance bacterial dynamics. These results evidence practical value for scientific research and lay the foundation for agricultural promotion of composting. [ABSTRACT FROM AUTHOR]

Methane (CH 4 ) production and quality were enhanced by the co-digestion of cow dung and food waste (FW) mixed with organic fraction of municipal solid waste (OFMSW) under optimized conditions in bench and semi continuous-scale mode for a period of 30 days. A bacterium capable of high yield of CH 4 was enriched and isolated by employing activated sewage sludge as the inoculums. The thirteen bacterial isolates were identified through morphological and biochemical tests. Gas chromatography was used to analyze the chemical compositions of the generated biogas. CH 4 yields were significantly higher during co-digestion of Run II (7.59 L) than Run I (3.7 L). Therefore, the co-digestion of FW with OFMSW and Run II was observed to be a competent method for biogas conversion from organic waste resources. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the effect of different concentrations (0%, 2.5%, 5.0%, 7.5% and 10.0%) of medical stone (MS) on the lignocellulose degradation and organic matter humification during pig manure (PM) composting. The results indicated that the addition of MS drastically promoted the organic carbon and lignin degradation. Compared to the control, the decomposition rate of hemicellulose and cellulose was increased by 9.64–27.08% and 2.11–12.07% in MS added treatments. Meanwhile, MS amendment significantly improved the humification of composting process, and the humic acid contents in MS added treatments were 5.58–9.75% higher than control. The FTIR and synchronous fluorescence spectra indicated that the aromatization of final compost was promoted with increasing the MS amount. In addition, the application of MS blended composts could significantly improve the biomass and chlorophyll content of pachoi ( Brassica chinensis L.). Due to the effective performance of MS, the 10.0% MS was suggested for PM composting. [ABSTRACT FROM AUTHOR]

This study aimed to enhance methane production from mixed anaerobic digestion of cow manure and corn straw by adding hydrochar and biogas slurry reflux. The hydrochar characterization revealed that it can provide attachment for microbial growth, and abundant surface functional groups (such as C –O, C O, C –OH, and C –N) for adsorption. Direct interspecies electron transfer (DIET) mediated by surface oxygen-containing functional groups on hydrochar increased the methane yield. The experimental group added with hydrochar and biogas slurry reflux had the highest methane and biogas production (34.40% and 36.98% higher than the control group, respectively). Results demonstrate hydrochar and biogas slurry reflux can improve microorganism species richness in anaerobic digestion systems, in which hydrochar can also improve microorganism species uniformity. Distance-based redundancy analysis showed that the VFAs, and pH had the greatest effects on the composition of the microbial community. The dominant microorganism at the phylum level in AD system were Bacteroidetes, Firmicutes, and Proteobacteria. The addition of hydrochar and biogas slurry reflux can significantly increase the species abundance of Methanobacterium. These results indicate that the addition of hydrochar and biogas slurry reflux can improve the corresponding microbial abundance, in which hydrochar can enhance the redox characteristics and DIET between microorganism, biogas slurry reflux can also increase nutrient content of anaerobic digestion system, and collectively promote the methane yield. [Display omitted] • Biogas slurry replaces water in anaerobic digestion to reduce the discharge of biogas slurry. • Hydrochar enhanced interspecific electron transfer and biogas slurry increased species diversity. • The methane yield of the HBSG was 34.40% higher than that of the control group. • Methanobacterium and Methanobrevibacter account for a large proportion in HBSG system. [ABSTRACT FROM AUTHOR]

An ever increasing demand for animal protein products has posed serious challenges for managing the increasing quantities of livestock manure. The choice of treatment technologies is still a complicated task and considerable debates over this issue still continue. To build a clearer picture of manure treatment framework, this study was conducted to review the most frequently employed manure management technologies from their state of the art, challenges, sustainability, environmental regulations and incentives, and improvement strategies perspectives. The results showed that most treatment technologies have focused on the solid fraction of manure while the liquid fraction still remains a potential environmental threat. Compared to other waste to energy solutions, anaerobic digestion is the most mature technology to upgrade manure's organic matter into renewable energy, however the problems associated with high investment costs, operating parameters, manure collection, and digestate management have hindered its developments in rural areas in developing countries. Bio-oil production through hydrothermal liquification is also a promising solution, as it can directly convert the wet manure into biofuel. However, lipid-poor nature of manure, operational difficulties, and the need for downstream process to remove nitrogenous compounds from the final product necessitate further research. Livestock manure management (both solid and liquid fractions) under biorefinery approach seems an inevitable solution for future sustainable development to meet circular bioeconomy requirements. Much research is still required to establish a systematic framework based on regional requirements to develop an integrated manure nutrient recycling and manure management planning with minimum environmental risks and maximum profit. • Challenge and future perspective of manure management technologies are discussed. • Manure management technologies were compared from environmental viewpoints. • Role of different groups involve in manure management circular loop was established. • Product is the vital link of the policy, technology and environment assessment. [ABSTRACT FROM AUTHOR]

• Black Tourmaline (TM) were added into pig manure and sawdust for composting. • Maximum value of HA/FA was observed in 10% TM added treatment. • TM promoted the transformation from NH 4 +-N to amino organic nitrogen. • 10% TM added treatment had the minimal nitrogen loss caused by NH 3 and N 2 O. • Total organic carbon was main factor driving changes of enzymatic activities. This study aimed to reveal the role of Black Tourmaline (TM) in the humification enhancement and the mechanism of nitrogen transformation during pig manure composting. Results showed that adding TM promoted the maturity and improved the humification degree by 20.13–33.77%. And TM was beneficial for the transformation from NH 4 +-N to amino organic nitrogen to fix more nitrogen in compost mass. Then NH 3 and N 2 O volatilization were decreased by 22.88–34.76% and 69.79–87.47% by comparison with the control, and the minimum value in nitrogen loss (26.78%) was observed in the 10% TM blended treatment. Furthermore, through RDA analysis, the protease an upmost contributor to nitrogen transformation. Meanwhile, total organic carbon was dominant factor affected enzymatic activities. Therefore, 10% TM was suggested to reduce nitrogen loss and increase humification in this research. Deeply related research in gene and specific addition amounts of TM will be investigated later. [ABSTRACT FROM AUTHOR]

• Effect of FCGS in bacteria community during the pig manure composting was investigated. • Firmicutes , Proteobacteria and Tenericutes were the primary dominant bacteria. • Firmicutes obtained significantly highest abundance bacteria among all treatment. • 6% FCGS treatment was appropriate proportions ratio to enhance bacteria growth. In present study, evaluate the effect of fine coal gasification slag (FCGS) as additive on abundance of bacterial diversity during pig manure composting. The six different dosages of FCGS 0% (T1), 2% (T2), 4% (T3), 6% (T4), 8% (T5) and 10% (T6) (dry weight basis) were mixed with original raw materials for 42 days an aerobic composting. The results indicated that FCGS adopted could affect the succession of bacterial diversity in different ways. Among all treatments, Firmicutes , Proteobacteria , Tenericutes , unidentified_Bacteria , and Actinobacteria were the highest abundance in weighted unifrac distance but Firmicutes ; Proteobacteria , Actinobacteria , Bacteroidetes , and Spirochaetes were main bacteria in unweighted unifrac distance. The β-diversity and principal component analysis indicated a significant difference in bacterial diversity in all treatments which T4 obtained difference obviously. Therefore, the results showed that T4 was a potential candidate to enhance significantly abundance of bacterial community in PM compost. [ABSTRACT FROM AUTHOR]

• Greenhouse gases emissions were alleviated from 121.32 to 30.16 g/kg. • Total nitrogen and carbon losses were 9.91–35.62 g/kg and 189.54–754.32 g/kg. • Maturity improved with germination index from 50% to 100% in final composts. • Gaseous and physicochemical parameters be have a significantly correlation. • Optimum combination approach was existed in T6. This study focused on evaluate the effectiveness of biochar alone compare integrated with bacterial consortium amendment on the gaseous emissions mitigation as well as carbon and nitrogen sequestration during pig manure composting. Six additive treatments were performed based on uniform mixing pig manure with wheat straw [bacterial consortium (T2), 12%wood biochar (T3), 12%wood biochar + bacterial consortium (T4), 12%wheat straw biochar (T5), 12%wheat straw biochar + bacterial consortium (T6), while T1 without any additive]. The results obviously indicated that integrated use of biochar and bacterial consortium could remarkably relieved gaseous emissions, improved carbon and nitrogen conservation as well as accelerated maturity of composting. Notably the optimum combination was existed in T6 owing to lowest nutrient losses (nitrogen and carbon losses were 9.91 g/kg and 189.54 g/kg) and gas emissions (30.16 g/kg) as well as supreme maturity (germination index > 100%); it's an economic-practical and environmental protection novel disposal approach for solid waste. [ABSTRACT FROM AUTHOR]