鸡粪堆肥的酶活特性研究

目的研究以鸡粪和菌糠为主体物料在高温堆肥发酵过程中纤维素酶、木聚糖酶、淀粉酶以及蛋白酶酶活性的变化。方法通过测定各酶活动态变化,了解各酶在鸡粪堆肥中的变化规律。其中纤维素酶和淀粉酶采用DNS比色法,木聚糖酶活采用还原糖法,蛋白酶活采用福林法进行测定。结果随温度不断变化和酶本身的性质以及物料的作用机制机制不同,酶活动态变化表现出一定的差异性。物料发酵温度在0～3 d时迅速上升,在3～18 d持续高温期,15 d之后下降趋于恒定。各酶活变化基本上符合先上升至峰值再下降,最后保持恒定的规律。其中各酶发生高效反应的时间具有不一致性,纤维素酶活在第18天时达到峰值,淀粉酶活在第9天时达到峰值,木聚糖酶在第12天时达到峰值,而蛋白酶活在第3天时即达到峰值。结论酶对物料腐熟具有重要用,本研究结果为堆肥腐熟提供参考指标,对优化堆肥工艺具有重要意义。     

猪粪堆肥化处理过程中的氮素转变及腐熟度研究

经过63d堆肥化处理后,猪粪与木屑混合堆肥及猪粪,木屑与树叶混合堆肥的T－N分别从开始的1．57％和1．78％增加到2．0％和2．11％;水溶性NO3－N／水溶性T－N均从接近于0的水平增加到3％左右;水溶性有机N／水溶性T－N分别增加到70％和76％;水溶性NH4－N／水溶性T－N则分别从开始52％和61％下降至堆肥结束时的30％和24％。种子发芽系数的测定结果表明,加入树叶有利于猪粪的腐熟化,可使猪粪堆肥化处理所城的时间从42d缩短至35d。化学指标与种子发芽系数的相关分析结果表明,水溶性NH4－N／水溶性T－N,水溶性NO3－N／水溶性T－N和水溶性有机N／水溶性T－N均与种子发芽系数呈显著相关,可作为堆肥的腐熟度评价指标。     

猪粪好氧堆制不同阶段氧气含量变化特征

研究了不同堆肥阶段氧气浓度和耗氧速率的变化特征．结果表明,不同堆肥阶段通风补充氧气所需的时间很短,各阶段通风后氧气浓度都恢复到17％以上．堆肥升温阶段、高温阶段初期耗氧速率高,达900μl·L^-1·s^-1以上;随着堆肥的进行,耗氧速率逐渐降低,经过5～7d的持续高温期后,耗氧速率下降到100μl·L^-1·s^-1以下,堆肥基本腐熟．根据耗氧堆肥的氧气动态变化特征,提出了相应的通风策略．     

畜禽粪便好氧堆肥过程氧化亚氮排放机制

好氧堆肥是实现畜禽粪便处理及资源化的有效途径,但畜禽粪便好氧堆肥过程是全球温室气体N2O的潜在来源,与全球温室效应和大气臭氧空洞等问题密切相关.随着畜禽养殖规模的扩大和畜禽粪便堆肥产量的急剧提升,畜禽粪便好氧堆肥过程N2O排放问题日趋严重,堆肥过程N2O排放机制机理研究引发学者们的关注.本文综述了畜禽粪便好氧堆肥过程中N2O的产生途径、排放规律、排放影响因素及其相关微生物学机理研究动态,总结了该过程中减排N2O的措施,并对该领域的研究趋势进行了展望.     

畜禽粪便堆肥过程中氮素的损失与控制

堆肥是实现畜禽粪便处理及资源化利用的有效途径,然而畜禽粪便堆肥过程中氮素损失较严重,对氮素损失与控制的研究可为有效控制氮素损失提供理论基础和实践参考.本文简述了畜禽粪便堆肥过程中氮素转化及主要损失途径,总结了影响堆肥氮素损失的主要因素(包括堆肥物料初始特性、堆肥环境参数和堆肥工艺条件),并综述了氮素损失控制措施(调节C、N代谢,改变氮素形态,添加NH₃吸附剂和调节通风与控温措施)的研究进展,此外,对未来的研究方向进行了展望.     

Pile mixing increases greenhouse gas emissions during composting of dairy manure

The effect of pile mixing on greenhouse gas (GHG) emissions during dairy manure composting was determined using large flux chambers designed to completely cover replicate pilot-scale compost piles. GHG emissions from compost piles that were mixed four times during the 80 day trial were approximately 20% higher than emissions from unmixed (static) piles. For both treatments, carbon dioxide (CO(2)), methane (CH(4)), and nitrous oxide (N(2)O) accounted for 75-80%, 18-21%, and 2-4% of GHG emissions, respectively. Seventy percent of CO(2) emissions and 95% of CH(4) emissions from all piles occurred within first 23 days. By contrast, 80-95% of N(2)O emissions occurred after this period. Mixed and static piles released 2 and 1.6 kg GHG (CO(2)-Eq.) for each kg of degraded volatile solids (VS), respectively. Our results suggest that to minimize GHG emissions, farmers should store manure in undisturbed piles or delay the first mixing of compost piles for approximately 4 weeks.     

The behavior of tetracyclines and their degradation products during swine manure composting

The purposes of this study were to investigate the behavior of three tetracyclines including chlortetracycline (CTC), oxytetracycline (OTC) and tetracycline (TC) and their degradation products in a pilot scale swine manure composting, and also to study the degradation kinetics of CTC, OTC and TC. During the pilot scale composting, CTC, OTC and TC were degraded by 74%, 92% and 70%, respectively. Several degradation products were found like 4-epitetracycline (ETC), 4-epioxytetracycline (EOTC), 4-epichlortetracycline (ECTC), demeclocycline (DMCTC) and anhydrotetracycline (ATC). Both the simple and the adjusted first-order kinetic models successfully fit the degradation process of CTC, OTC and TC during the composting, but the adjusted first-order kinetic model fit much better with the calculated half-lives of 8.2, 1.1 and 10.0 days, respectively.     

Changes in functional abilities of the microbial community during composting of manure

The objective of this study was (a) to detect changes of the functional abilities of the microflora during composting of manure as a result of windrow turning frequency and (b) to detect differences between distinct zones within the windrows. Biolog GN microtiter plates containing 95 different carbon sources were inoculated with diluted suspensions of compost material containing 15,000 microorganisms per well (120 l). We found a dramatic shift in functional microbial community structure during the 8-week composting process. The shift was more rapid when the compost windrows were turned. The substrate use pattern in the outer, well-aerated zone of the unturned windrow was similar to that of the turned windrows. Microbial biomass and respiration decreased more rapidly in the turned than in the unturned windrows, indicating a different pace of compost maturation. The data suggest that the Biolog assay may be a suitable approach to determine compost maturity. Correspondence to: H. Insam     

奶牛粪好氧堆肥过程中不同含碳有机物的变化特征以及腐熟评价

对奶牛粪好氧堆肥过程中不同含碳有机物的变化特征以及腐熟程度进行了研究。根据腐熟指标(温度、种子发芽率、种子发芽指数、大肠杆菌以及蛔虫卵死亡率)的要求,奶牛粪经过堆肥后能够达到腐熟要求。堆肥过程中全碳、易氧化有机碳呈逐渐下降趋势,腐殖酸碳呈逐渐增加的趋势;微生物量碳和水溶性碳呈先增后降而后平稳的变化趋势;氧化稳定系数和H/F比(胡敏酸与富里酸比值)呈先降后增的变化趋势,而胡敏酸的E4/E6值(465和665nm处吸光系数比值)与氧化稳定系数和H/F比变化趋势相反。通过相关性分析发现,堆肥过程中易氧化有机碳和腐殖酸碳是影响全碳变化的主要因素;易氧化有机碳、腐殖酸碳、氧化稳定系数、H/F比、E4/E6值均能很好地表征奶牛粪堆肥的腐殖化和稳定化程度;微生物量碳和水溶性碳之间存在相互转化的关系。     

微生物菌剂对猪粪堆肥中细菌群落结构的影响

以猪粪和小麦秸秆做堆肥试验,处理组添加外源微生物菌剂,利用常规方法对堆肥样品进行理化性状测定,采用高通量测序技术分析堆肥过程中细菌群落特征。理化性状测定结果表明: 添加外源菌剂可延长堆肥高温时间,降低堆肥发酵末期的pH,增加全氮含量,加快C/N的下降。主成分分析表明: 外源菌剂影响堆肥样品细菌群落的稳定性。门分类水平上,厚壁菌门、变形菌门和绿弯菌门的相对丰度在处理组中较高;纲分类水平上,梭状芽孢杆菌纲、α-变形菌纲和γ-变形菌纲在处理组的升温期和高温期相对丰度增加;科分类水平上,小单孢菌科和梭状芽孢杆菌纲的消化链球菌科、梭菌科以及盐厌氧菌科的相对丰度在处理组的升温期和高温期均呈上升趋势。Pearson相关性分析表明,盐胞菌属与外源菌剂呈显著正相关,而氨苄芽孢杆菌属与外源菌剂呈显著负相关。研究表明,猪粪堆肥中添加外源菌剂可使堆肥的理化性质和细菌群落结构均发生显著变化。     

Microbial dynamics and enzyme activities during rapid composting of municipal solid waste - a compost maturity analysis perspective

An investigation was carried out in the laboratory to find out the microbial dynamics and enzyme activities during rapid composting of municipal solid waste (MSW). Various treatments such as aeration (A), addition of chemical agents (glucose (G) and acetic acid (AA) and application of cellulolytic microbial (M) inoculum (Phanerochaete chrysosporium and Trichoderma reesei) were used to facilitate the decomposition of MSW. The result of the present investigation revealed that the degradation of organic substrates were quick (within 9-12 days) in case of rapid composting as indicated by the reduction (below 20) in C/N ratio. Whereas, normal composting took more than 20 days to attain C/N ratio of below 20. Estimation of selected enzymes (amylase, protease, phosphatase and cellulase) provided information on the substrate specific degradation profiles of various labile substrates contained in organic waste.     

New insights into the structure and dynamics of actinomycetal community during manure composting

Despite advancing knowledge about the functional role of actinomycetes in degrading lignocellulosic materials, definitive knowledge concerning the diversity and dynamics of the actinomycetal community in composting is still lacking. In this study, real-time polymerase chain reaction (PCR) coupled with denaturing gradient gel electrophoresis (DGGE) and clone library construction were applied to investigate actinomycetal diversity and dynamics in a pilot-scale composting. Quantitative real-time PCR data revealed that actinomycetes accounted for 18–86 % of bacteria and that the fraction peaked during the maturing phase, indicating that Actinobacteria were critical to the compost ecosystem. Qualitatively, actinomycetal communities displayed distinct temporal variations during composting. Fourteen distinct genera of actinomycetes and an unknown group were observed in manure composts. Redundancy analysis indicated that temperature exerted an influence over the actinomycetal communities. Specifically, pathogenic Corynebacterium species dominated in the initial phase, whereas the genera Saccharomonospora and Thermobifida were abundant in the thermophilic phase. In maturing composts, mesophilic Micrococcineae members were most prevalent. The dominant thermophiles along with Micrococcineae may jointly facilitate the degradation of lignocellulosic materials during composting. Together, our research revealed a more detailed ecological and potential functional role for actinomycetes in the compost ecology.     

Rapid estimation of nutrients in chicken manure during plant-field composting using physicochemical properties

Regression equations which relate livestock and poultry manure nutrient content to its several physicochemical properties have been reported by previous researchers. This study explores the feasibility and efficiency to determine the nutrients (TN; TP; TK; Cu and Zn) in chicken manure during composting using physicochemical properties (pH, EC and DM), and compares the performances of regression equations in this study with those in the literature. The results show that DM is the best predictor to construct the single linear regressions for all the nutrients (R2≥0.84, p<0.001). In addition, the multiple linear regression equations based on DM and pH are all notable. These findings show the potential of physicochemical models for TN, TP, TK, Cu and Zn with more convenience and rapidness, but further research is needed to develop better models with higher accuracy for the above and other more nutrients.     

Microbial activities during composting of pulp and paper-mill primary solids

In this study, bench-scale aerobic reactors were used to monitor microbial activities and determine the degradability of pulp and paper-mill primary solids. Over the 43-day composting period, the level of microorganisms detected increased four-fold. However, based on amounts of CO2 produced, the increase expected was 19-fold, suggesting lysis of some cells in the population. The composition of the microbial population, determined through species identification by the BIOLOG® method, and by spot plating, changed throughout the composting process with Cellulomonas spp. not appearing until day 22. Chemical analyses suggested a fall of 33% in the cellulose content, but no other statistically significant chemical changes were observed.     

鸡粪好氧堆肥过程中细菌群落结构和功能分析

为了明确鸡粪好氧堆肥过程中细菌群落结构和功能的变化,采用高通量测序技术测定了好氧堆肥前、中、后3个时期样品的16S rRNA基因序列,并进行了生物信息学分析。结果表明, 3个堆肥阶段中仅有10%左右的分类操作单元(operational taxonomic units, OTUs)具有阶段特异性;不同发酵阶段细菌α多样性指数ACE、Chao1和Simpson均呈现先升高后降低的趋势,但各阶段间差异不显著(P<0.05)。3个发酵阶段优势菌门类相同,但丰度存在差异。线性判别分析[line discriminant analysis (LDA) effect size, LEfSe]法对细菌生物标志分析表明,从门到属水平共有49个物种,堆肥前期样品组中显著富集的物种最多,后期最少。原核分类群功能注释(functional annotation of prokaryotic taxa,FAPROTAX)对细菌功能多样性分析表明,堆肥前期细菌功能多样性最高,而随着发酵进行细菌功能富集程度增加、多样性降低。该研究为畜禽粪污好氧堆肥过程调控提供理论支撑和技术指导。     

Characteristics of dairy manure composting with rice straw

The aim of this work was to investigate the effects of aeration rate, aeration method, moisture content, and manure age on the characteristics of dairy manure composting with rice straw in terms of composting temperature, oxygen consumption rate, emission of odorous gases, and final compost property. It was found that the aeration rate of 0.25 L/min-kg VS was capable of achieving the highest composting temperature, longest retention time of high temperature, and less emission of odor gases. Except for the composting temperature reached, there was no significant difference between bottom-forced and top-diffusion aerations in terms of final compost property. The higher initial moisture content (65%) was more favorable for its higher temperature, longer retention time of high temperature, and more stable end compost obtained. Fresh manure showed better composting performance than the aged manure for its higher temperature reached in less time and less ammonia emission. Oxygen consumption rates were basically similar to those of temperatures. Most emissions of the odorous gases occurred during the first week of composting, therefore, special attention should be paid to this period of time for effective odor control.     

An assessment of pathogen removal during composting of the separated solid fraction of pig manure

The aim was to investigate pathogen survival during composting of pig manure solids with and without bulking agents in two trials of 56 days duration, each with four treatments. Salmonella was detected in the sawdust and straw bulking agents but was undetectable in the compost, except in one treatment at day 0. Enteric indicator organisms were reduced by day 7 (P<0.001) and were undetectable in the final compost, except for coliform which were present at 3.66-4.43 log?? CFU/g. Yeasts and moulds were reduced and aerobic spore-formers remained stable in one trial but both increased in the other (P<0.001). Bacillus licheniformis and Clostridium sporogenes were the predominant culturable spore-forming bacteria recovered. Microbial counts were influenced by the bulking agent but only at particular time points (P<0.05). Overall, the pig manure-derived compost complied with EU regulations for processed manure products, as E. coli and Enterococcus were below limits and it was Salmonella-free.     

不同微生物菌剂处理对猪粪堆肥中氨挥发的影响

研究不同微生物复合菌剂及添加比例对猪粪与木屑混合(鲜重比为鲜猪粪∶木屑9∶1)堆肥过程中NH₃挥发的影响.结果表明,在堆肥过程中,NH₃挥发主要产生在堆肥前期15 d的升温和高温期,添加3‰的微生物复合菌剂1、2和3对猪粪堆肥中NH₃挥发都有一定的抑制作用,减轻氮素损失与堆肥恶臭,添加5‰复合菌剂1有显著抑制作用（P＜0.05）.     

A survey of ammonia-assimilating micro-organisms in cattle manure composting

AIMS: To evaluate the ammonia-assimilating abilities of micro-organisms isolated from cattle manure composting processes and to determine the distribution of cultivable species of ammonia-assimilating micro-organisms in microbial communities during the composting processes. METHODS AND RESULTS: Compost samples were collected from four stages of treatment. Trypto soya agar was used for the isolation of ammonia-assimilating aerobes. Many of the isolates showed high ammonia-assimilating ability in a medium containing basal components and a compost extract. Partial 16S ribosomal DNA sequencing showed that the cultivable species of highly efficient ammonia-assimilating isolates changed during the composting process. The community structure of micro-organisms and actinomycetes was analysed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Two species of actinomycetes identified by PCR-DGGE coincided with those found among the cultured isolates. CONCLUSIONS: Ammonia-assimilating micro-organisms obtained by the cultivation method were not predominant in the microbial community during the composting process: however certain cultured actinomycetes were members of predominant species in the actinomycetes community. SIGNIFICANCE AND IMPACT OF THE STUDY: Ammonia assimilation by micro-organisms is one of the important mechanisms for ammonia retention in the composting process. Cultivable actinomycetes are a means for preventing ammonia emission from the composting process.