Changes in Thermophilic Bacteria Population and Diversity during Composting of Coal Fly Ash and Sewage Sludge

The thermophilic bacteria in compost made from coal flyash-amended sewage sludge were isolated and identified using theBiolog system to investigate the effect of coal fly ash on thethermophilic decomposition of sewage sludge during composting. Atotal of 8 species of Bacillus were isolated from thecompost and Bacillus brevis was the dominant speciesduring the entire composting process. The present resultsdemonstrate that the Biolog system is a fast and simple methodfor identifying bacterial species in compost, provided thatoptimum conditions could be achieved for the Bacillusculture. Adding coal fly ash as an amendment did not change thedominant bacteria species during composting, but decreased thepopulation and diversity of thermophilic bacteria species due tothe high alkalinity and salinity. Fewer thermophilic bacteriawere detected in ash-amended sewage sludge compost than insludge compost. There was also reduced metabolic activityobserved in the ash-amended sludge compost from the data ofCO₂ evolution and weight loss. Although ash amendmentdemonstrated a negative effect on the population and diversityduring thermophilic phase, it did not cause any significanteffect on compost maturity.     

微生物菌剂对猪粪堆肥过程中堆肥理化性质和优势细菌群落的影响

  【目的】  掌握猪粪堆肥过程中微生物群落的演替规律与理化指标的相互关系,对提高猪粪堆肥营养品质和加速堆肥进程具有重要的意义。  【方法】  以猪粪和玉米秸秆 (质量比6∶1) 混合物为堆肥原料,耐高温菌剂主要含Acinetobacter pittii、Bacillus subtilis subsp. Stercoris和Bacillus altitudinis。堆体设接种菌剂 (MI) 和未接种 (对照,CK) 两个处理。常规监测堆肥温度和理化指标值,于堆肥开始后第4、12、24和32天采集样品,以16S rRNA高通量测序技术研究堆肥细菌群落的变化。用堆肥第4、12、24和32天采集的新鲜样品制备浸提液,进行紫花苜蓿种子发芽试验。堆肥结束时,测定全氮、全磷和全钾含量,并探讨微生物菌剂对堆肥理化指标和细菌群落演替的影响。  【结果】  接种微生物菌剂可使堆肥高温期提前2天出现,并且能延长高温期2天。堆肥浸提液的促生试验发现,在堆肥24天后紫花苜蓿种子发芽指数 (GI) 大于80%,且MI对幼苗主根的促生能力大于CK (P < 0.05)。随着发酵过程的进行,堆体体积不断缩小,CK和MI中全钾 (TK) 和全磷 (TP) 含量一直呈增加趋势,在堆肥第32天,CK和MI的全磷含量分别为2.28%和2.63%,处理间差异显著 (P < 0.05),而全钾含量分别为1.81%和1.86%,全氮含量分别为2.65%和2.63%,pH分别为8.72和8.78,处理间差异均不显著。在整个堆肥过程中,MI和CK的pH变化范围分别为8.40～8.95和8.61～8.93;CK和MI中总有机碳 (TOC) 的降解速率在堆肥的4～12和24～32天均表现为MI大于CK,CK和MI的碳氮比 (C/N) 分别为13.28和15.26,差异显著 (P < 0.05)。堆肥过程中在门水平上占据主导地位的细菌群落主要包括 Proteobacteria、Actinobacteria、Firmicutes和Bacteroidetes,在堆肥的高温期 (堆肥24天),堆体CK和MI中Firmicutes的相对丰富度分别为17.4%和59.8%;在堆肥的升温期、高温期和腐熟期,优势门水平细菌群落Proteobacteria、Firmicutes和Actinobacteria依次演替,且MI堆体中细菌群落的相对丰度均大于CK。属水平优势细菌为Acinetobacter、Lysinibacillus、Solibacillus、Pseudomonas和Flavobacterium,添加微生物菌剂可使Acinetobacter的丰度在堆肥第4天增加21.41%,此外,添加复合微生物可使堆肥第12天的Shannon和Observed species指数增加。相关性分析表明,温度、全N (TN)、TP、TK、TOC及GI与堆体中细菌组成具有显著相关性,而pH和细菌的相关性不显著。  【结论】  在堆体内接种微生物菌剂可显著提高并维持堆肥过程中优势门、属细菌群落的丰度,进而促进堆体升温并延长高温时期,缩短堆肥腐熟周期,加快总有机碳的分解,最终提高堆肥产品中有效磷的含量。复合微生物菌剂在堆肥升温期起主要作用的为Acinetobacter pittii,高温期为Bacillus subtilis subsp. Stercoris和Bacillus altitudinis,我们建议筛选耐高温细菌时应集中在厚壁菌门的芽孢杆菌属。     

接种方式对堆肥过程中功能菌定殖的影响

利用园林绿化废弃物添加磷矿粉,在堆肥前期、后期以及前后期分两次接种复合菌剂进行好氧堆肥,通过抗生素标记、选择性培养基方法,研究堆肥过程功能菌（解磷菌、拮抗菌）的定殖状况,分析堆肥产品的微生物群落功能多样性、解磷效果以及对青枯病菌的拮抗性能。结果表明：堆肥后期和分前后两次接种复合菌剂明显增加堆肥枯草芽孢杆菌、胶质芽孢杆菌功能菌数量,而前期接种经过堆肥高温期,堆体功能菌数量锐减,表明功能菌定殖效果取决于是否后期接种;堆肥后期和分前后两次接种显著提高了堆肥的微生物群落功能多样性、堆肥水溶性磷和有效磷含量以及堆肥对青枯病菌拮抗性能。     

Assessment of Microbial Communities In Decomposition of Specified Risk Material Using a Passively Aerated Laboratory-Scale Composter

The occurrence of bovine spongiform encephalopathy (BSE) in Canada has resulted in the implementation of regulations to remove specified risk material (SRM) from the food chain. SRM includes the distal ileum of all cattle, and the skull, brain, trigeminal ganglia, eyes, palatine tonsils, and spinal cord and dorsal root ganglia of cattle ≥30 months of age. Composting may be a viable alternative to rendering for SRM disposal. In our study, two bulking agents, barley straw and wood shavings, were composted with beef manure along with SRM in passively aerated, laboratory-scale composters. Both composts heated rapidly, exceeding 55°C after 3 days with oxygen declining in the early composting stage with wood-shaving compost, but returning to near-original levels after 5 days. During composting the two matrices differed (P <0.05) only in water content, TC and bulk density. In the final compost, water content, TC and C/N ratio were higher (P < 0.05), while EC was lower (P < 0.05) in the wood shavings as compared to the straw compost. Approximately 50% of SRM was decomposed after 15 days of composting, with 30% of SRM being decomposed within the first 5 days. Phospholipid fatty acid (PLFA) profiles were used to characterize the microbial communities and showed that Gram positive bacteria were predominant in compost at day 5, a point that coincided with a rapid increase in temperature. Gram negative bacteria and anaerobes declined at day 5 but populations recovered by day 15. Fungi appeared to be suppressed as temperatures exceeded 55°C and did not appear to recover over the remainder of the composting period, with the exception of the straw compost at day 15. On day 5, Actinomycetes increased in the straw compost, but declined in the wood shavings compost, with this group increasing in both types of compost at day 15. Although temporal changes were evident, compost matrices or depth within the composter did not obviously influence microbial communities. Decomposition of SRM also did not differ between compost matrices or with depth in the composters. These results suggest that SRM decompose rapidly during composting and that both mesophilic and thermophilic microbial communities play a role in its decomposition.     

嗜热复合菌对堆肥品质及微生物群落演替的影响

  【目的】  研究嗜热复合菌对畜禽粪污堆肥理化特性和腐熟度的影响,探讨嗜热菌影响堆肥过程的微生物机制。  【方法】  堆料由75%羊粪和25%养鸡发酵床垫料构成,初始原料C/N为28,堆料量1.2 t,高度70～90 cm,开放条垛式堆沤。处理组为堆肥添加0.1%嗜热菌B. fordii FJAT-51578和U. thermosphaericus FJAT-51579等比混合的发酵液,对照组为添加1%市售枯草芽孢杆菌堆肥菌剂(Bacillus subtilis)。堆肥时间为2021年9月18日—10月14日,每两天检测1次温度。堆肥前15天,每两天进行一次翻抛,后期每5天进行一次翻抛,保持堆肥含水量50%～60%,直至高温期结束。在堆肥开始后第1、9和26天取堆肥样品,分析氮磷含量、硝化指数和种子发芽指数。结合扩增子测序,分析堆肥细菌群落结构变化,并揭示其主要环境影响因子。采用PICRUSt分析堆肥有效氮和有效磷代谢的微生物机制。  【结果】  嗜热复合菌添加促进堆肥硝化指数的降低和种子发芽指数的升高,促进堆肥腐熟;堆肥产物碱解氮和有效磷的含量分别比市售菌剂组高11.8%和7.7%。同时,嗜热复合菌的添加改变了细菌群落的分布,降低了堆肥细菌的多样性和丰富度,提高了糖单胞菌、链霉菌和嗜热葡萄孢菌等降解菌的丰度。RDA分析表明,pH和C/N是影响堆肥微生物群落多样性的主要因素,碱解氮与芽孢杆菌和糖单胞菌属丰度正相关,有效磷与嗜热裂孢菌、直丝菌属和马杜拉放线菌属丰度正相关。氮、磷代谢相关京都基因和基因组百科全书同源基因(KO)的PICRUSt分析显示,微生物氮磷循环相关KO的丰度随着堆肥进程均有所增加。添加嗜热菌剂提高了氨化、铵同化、硝酸盐同化、同化/异化硝酸盐还原等氮循环相关KO,及无机磷溶解、酸性磷酸酶和碱性磷酸酶等磷循环相关KO。  【结论】  在畜禽粪污堆肥中添加嗜热复合菌剂加快并延长了高温期,降低了C/N,提高了堆肥中碱解氮和有效磷含量,其中C/N、硝化指数和GI指数等指标在堆肥中期达腐熟程度标准,促进堆肥腐熟。堆肥中添加嗜热复合菌剂增加了细菌氮磷代谢相关KO的表达,提高了腐熟中期堆肥中嗜热菌的丰度和种类,碱解氮与芽孢杆菌和糖单胞菌属丰度呈正相关,有效磷与嗜热裂孢菌、直丝菌属和马杜拉放线菌属丰度正相关。因此,添加嗜热复合菌促进了堆肥有效氮磷的含量。     

A Newly Isolated Thermophilic Bacterium,Bacillus Licheniformis HA1 to Accelerate the Organic Matter Decomposition in High Rate Composting

Efficacy of various compost starter cultures was tested in a bench-scale composting system utilizing a ceiling process temperature of 60°C. Variables tested with time were CO₂ and NH₃ evolution, conversion of carbon and the succession of microorganisms in the compost. When an initial compost pH of 7.0 was used, a laboratory produced starter culture (Culture A) was much less effective than a commercial culture (Culture B). Low activity in the experiment with Culture A was due to a low pH(<5.5) that developed within 30 h after inoculation. Inoculation of Culture A with a thermophilic strain (HA1) of Bacillus licheniformis isolated from Culture B prevented the decrease in pH and significantly increased the rate of decomposition. It also enhanced populations of other thermophilic bacterial groups during the process.     

添加酸解氨基酸对植物源废弃物好氧堆肥品质及其应用效果的影响

  【目的】  探究添加酸解氨基酸 (AA) 对不同植物源废弃物堆肥进程、氮素损失阻控、堆肥品质和产品效果的影响。  【方法】  分别向3种含碳量不同的植物源废弃物 (中药渣、木薯渣和蘑菇渣) 中添加5%、10%和15% (体积质量比) 的酸解氨基酸,以不添加酸解氨基酸处理作为对照,监测堆肥过程中的温度和理化指标。堆肥结束后,以辣椒和茄子作为供试作物进行盆栽和大田试验。盆栽试验以不施肥和施化肥为对照,试验处理包括9个堆肥产品及其添加促生菌 (解淀粉芽孢杆菌SQR9) 制备的生物有机肥产品,共24个,调查了不同处理辣椒和茄子的生物量和生理指标。田间试验以不施肥和施化肥为对照,以盆栽效果最佳的堆肥产品及其制备的生物有机肥单施、两个产品分别与化肥配合,共14个处理,调查了辣椒和茄子的生长状况。  【结果】  添加酸解氨基酸延长了中药渣和木薯渣堆肥的高温期持续时间,而蘑菇渣堆肥的高温期持续时间随酸解氨基酸添加量的增加而减少。酸解氨基酸加入后,3种原料堆体的pH均有所下降,且整体上酸解氨基酸添加量越多,pH下降越显著。酸解氨基酸明显促进了3种原料堆肥中纤维素、半纤维素和总碳的分解,且促进效果和氮磷钾养分积累量随着酸解氨基酸添加量的增加而提高。此外,酸解氨基酸加入后由于引入H+,使堆体的电导率有小幅上升。盆栽试验表明,3种有机物料堆肥均以添加10% AA制成的有机肥最佳,且能显著提高辣椒植株的鲜重、干重、株高、茎粗和叶绿素含量,添加促生菌后进一步提高了堆肥的效果。以10% AA处理的有机肥及其生物有机肥进行大田试验,中药渣有机肥中,生物有机肥处理为辣椒田间处理最佳,生物有机肥加化肥处理为茄子田间处理最佳;木薯渣有机肥处理中,生物有机肥处理在辣椒和茄子田间试验中均为最佳处理;蘑菇渣有机肥处理,生物有机肥加化肥处理在辣椒和茄子大田试验中各项指标均为最优;表明10% AA处理的有机肥配合功能菌株施用能促进作物生长、提高作物产量,整体效果显著优于空白和化肥处理。  【结论】  添加酸解氨基酸能够降低堆肥pH,减少堆肥过程中的氮素损失,延长堆肥高温期的持续时间,提高有机碳降解效率及氮磷钾相对含量;该堆肥与功能菌株配伍制成的生物有机肥,与等养分化肥处理相比,可以显著提高作物的生物量和产量。     

农林废弃物对厨余垃圾堆肥腐殖化的影响与微生物驱动机制

高碳源农林辅料复配是实现厨余垃圾好氧堆肥促腐提质的关键技术,但不同辅料对厨余垃圾堆肥过程腐殖化的影响及其相应的微生物驱动机制仍不清楚,从而限制了对辅料的有效筛选与利用。为此,该研究选用园林废弃物、玉米秸秆和西瓜秧3种典型高碳源农林废弃物为辅料,探究其对厨余垃圾堆肥过程有机质腐殖化的调控效果与机制。研究结果表明：相较于园林废弃物和西瓜秧,添加15%玉米秸秆（湿质量）作为辅料,能够有效调节堆体物料结构,富集功能微生物,促进厨余垃圾堆肥产物腐熟度提升,种子发芽指数可达139%。具体而言,西瓜秧蛋白质含量较高,作为辅料能够在堆肥初期促进堆体快速升温,但不利于高温期延续,且产物腐殖化程度较低。相比之下,园林废弃物和玉米秸秆添加可以在高温期和降温腐熟期富集更多Ureibacillus、Bacillus Oceanobacillus和Flavobacterium等具有木聚糖降解和纤维素降解功能的细菌,促进有机质转化为多酚、氨基酸等腐殖质前驱物,进而推动稳定的腐殖酸生成。特别是玉米秸秆作为辅料时有效增加了具有木质纤维素降解功能的细菌,从而能够加速有机质的降解,促进腐殖化提升75%,研究结果为选取适宜的辅料强化厨余垃圾堆肥产品品质提供参考。     

Chemical,Physical and Biological Criteria for Maturity in Composts for Organic Farming

Properties of organic farming composts were examined during the composting process: pH, electrical conductivity, C/N ratio, total N content, NH₄₊ content, NO_3?content, ash content, and organic matter content. In addition to these properties the respiration rate, microbial population counts, hydrolysis of Fluorescein Diacetate (FDA) and the activity of the enzyme amidase were studied. Composts at several stages of maturity were incubated in soil, and their N mineralization rates were measured. The end of the thermophilic stage was characterized by irreversible decrease in pile temperature to under 55°C, followed by stabilization of the chemical properties. This stage in the composting process is also characterized by decrease in CO₂ evolution rate, changes in microbial populations and specific patterns in FDA hydrolysis and amidase activity. Based on this evidence, we suggest that biological parameters can be considered as indicators for compost maturity.     

Change in T4-type bacteriophage communities during the composting process of rice straw: Estimation from the major capsid gene (g23) sequences

The present study examined T4-type phage communities in rice straw (RS) under the composting process by analyzing the composition of the major capsid gene ( g23 ) of T4-type bacteriophages. The g23 clones were obtained from RS throughout the composting process from RS materials to composting RS in the curing stage (for 124 days). Most of the g23 clones were phylogenetically closely related to those in rice field soils and rice field floodwaters, and Paddy Groups II and III appeared to characterize the g23 genes in the composting RS. The diversity of g23 genes in the composting RS was highest in the RS material (day 0 after the onset of composting) and in the early thermophilic stage (day 7), and decreased markedly in the middle and curing stages. This change was in contrast to that of the bacterial community, which showed higher diversity in the middle and curing stages. There was no specific clone that characterized any stage during the composting process. These findings indicate that the phage community is not the major controlling agent in determining eubacterial succession and that the thermophilic stage in the composting process efficiently annihilated T4-type phages in the composting pile.     

Physical,Chemical and Biological Properties of an Accelerated Cassava Based Compost Prepared Using Different Ratios of Cassava Peels and Poultry Manure

Monitoring the physical, chemical and biological properties during accelerated composting enables concise determination of its stability and maturity. Determination of physical parameters such as pH, moisture and temperature, chemical parameters such as total nitrogen (N), phosphorus (P), potassium (K), organic matter and humic acid as well as biological parameters such as microbial count and carbon dioxide (CO₂) evolution was carried out during a four (4) week composting period, The trend observed for pH showed the mesophilic and thermophilic phases and a similar trend was observed for the compost temperature. Intermittent increase and decrease was observed for total N, P, K as well as for the fungal and bacterial population. A direct relationship was observed among the bacterial population, CO₂ evolution and humic acid. However, composting for four (4) weeks produced a stable compost, which was evident through the physical observation of the final product and the results obtained for the chemical and biological parameters.     

Change in T4-type bacteriophage communities during the composting process of rice straw: Estimation from the major capsid gene (g23) sequences

Abstract

The present study examined T4-type phage communities in rice straw (RS) under the composting process by analyzing the composition of the major capsid gene (g23) of T4-type bacteriophages. The g23 clones were obtained from RS throughout the composting process from RS materials to composting RS in the curing stage (for 124?days). Most of the g23 clones were phylogenetically closely related to those in rice field soils and rice field floodwaters, and Paddy Groups II and III appeared to characterize the g23 genes in the composting RS. The diversity of g23 genes in the composting RS was highest in the RS material (day 0 after the onset of composting) and in the early thermophilic stage (day 7), and decreased markedly in the middle and curing stages. This change was in contrast to that of the bacterial community, which showed higher diversity in the middle and curing stages. There was no specific clone that characterized any stage during the composting process. These findings indicate that the phage community is not the major controlling agent in determining eubacterial succession and that the thermophilic stage in the composting process efficiently annihilated T4-type phages in the composting pile.     

接种高温嗜热菌剂加快牛粪秸秆堆肥发酵进程

  【目的】  探究添加高温嗜热菌剂对牛粪堆肥的发酵效率、木质纤维素降解和堆肥品质的影响。  【方法】  以牛粪和玉米秸秆为原料进行堆肥。添加嗜热菌剂处理(GLL)的菌剂主要由普通高温放线菌(Thermoactinomyces vulgaris)、地尿素芽孢杆菌(Ureibacillus terrenus)和嗜热脱氮芽孢杆菌(Geobacillus thermodenitrificans)组成,以分别添加两个市售有机肥发酵菌剂的处理(A、B)为对照,同时设不接种菌剂的空白对照(CK),发酵试验为期30天。在堆肥第0、3、7、12、16、23、30天取样,烘干样用于测定堆肥木质纤维素含量,鲜样用于测定含水率、pH、电导率（EC）值、种子发芽率指数(GI)和细菌群落结构。  【结果】  GLL处理在堆肥第2天迅速升温至超高温期(85.8℃),超高温期持续5天;CK、A和B处理在堆肥第3天内进入高温期(分别为56.3℃、59.2℃和57.6℃),高温期分别持续了10、11和13天。接种GLL显著降低了堆肥水分含量,堆肥结束时含水量下降至34.3%,而CK、A和B处理的含水量分别下降至45.4%、43.8%和44.6%,未能满足产品水分标准。GLL处理半纤维素、纤维素和木质素在堆肥后比初始值分别下降81.6%、65.2%和53.7%,对木质纤维素的降解能力明显高于CK、A和B处理。在GLL处理堆肥高温期及超高温期,厚壁菌门细菌相对丰度增加到46.6%。接种GLL菌剂发酵后的堆肥产物的有机质、总养分、机械杂质质量分数及酸碱度、GI值等均满足NY/T 525—2021的要求。  【结论】  接种高温嗜热菌剂能够显著提高堆肥温度,延长高温期持续时间,实现超高温堆肥,降低水分含量,提高木质纤维素的降解效果,快速获得满足NY/T 525—2021要求的堆肥产品。     

A Comparison of Different Bulking Agents for the Composting of Fish Offal

An experiment comparing the effectiveness of three different bulking agents in the composting of fish processing wastes was carried out using small-scale composters operated at ambient temperatures. Fish offal was mixed with each of peat moss, sawdust and wood shavings in a 5:1 ratio by weight. The mixed materials were left undisturbed in the composters for an initial 55 days. They were then mixed and reloaded into their respective composters for a further 95 days of composting. Temperatures were monitored throughout the experiment, while serial physical and chemical analyses of the compost materials were initiated after the mixing. Headspace-gas chromatography was also used to determine the levels of phytotoxic organic acids and phenol. All the compost piles reached thermophilic temperature levels (40–70°C). Due to insufficient pile mass, temperatures over 55°C were not sustained for a sufficient length of time to satisfy the EPA requirements for pathogen reduction. The temperature profiles suggest that ambient temperatures near the freezing point can significantly influence the temperature of compost piles with volumes of 63 liters or less. The results reaffirm the potential of composting as a viable option for utilizing fish processing wastes and the suitability of peat moss, sawdust, and wood shavings as bulking materials. The physical and chemical qualities of the 150-day old composts were comparable to other seafood compost products. Peat moss gave the best results in terms of nitrogen conservation, but is the most expensive option. Monitoring the concentrations of phytotoxic organic acids and phenol using headspace-gas chromatography proved to be a useful method for establishing compost maturity.     

In-vessel,Mechanical Rotating Drum Composting Of Institutional Food Residuals

Use of composting technology as a treatment/disposal method for food residuals has been investigated by numerous researchers. This project evaluated the applicability of in-vessel, mechanical, rotating drum composting for food residuals. Three batches of food residuals (plate scrapings) were collected from a Texas prison and mixed with fine-textured soft-wood shavings at 2/1, 3/1 and 4/1 (ratios of shavings to food residual on a volumetric basis) to produce 0.4 m³ of compost blend. Temperature, oxygen, pH, bulk density and porosity were tracked throughout a fifteen-day composting trial. Volume and weight reductions were noticed for all blends. All blends reached thermophilic temperatures (> 45°C) while remaining aerobic during the trials. Initial pH was low in all blends, occasionally reaching 3.55 before returning to optimal levels (6.0 to 7.5) for composting. Temperature increases into the thermophilic range during composting corresponded to increases in compost pH. Most nutrients (P, K, Ca, Mg, S, Na and Zn) increased in concentration during the composting period, with the exception of N, which in some instances decreased over time. Composts utilizing the 3/1 ratio of bulking agent/food residual achieved thermophilic temperatures quickest and maintained temperatures longer than did other blending ratios. From this study, it appears that use of the mechanical, in-vessel, rotating drum composter may be a viable alternative for food residual disposal.     

微生物菌剂对油枯堆肥过程中理化性质的影响研究

以油枯为基本原料,采用好氧堆肥方式进行堆肥试验,研究了添加4种不同微生物菌剂的条件下,油枯-稻壳-甘蔗渣堆肥体系中pH、C/N、水溶性NO3--N、水溶性NH4＋-N中的动态变化规律及菌剂对高温堆肥腐熟进程的影响。结果表明,添加菌剂能有效缩短堆肥到达高温的时间,延长高温分解阶段,加快物料水溶性NH4＋-N和C/N降低,pH和水溶性NO3--N含量升高,加快了油枯堆肥腐熟化进程。添加VT菌剂的堆肥处理相比其他在堆肥15d后最先进入高温分解阶段,高温持续时间为10d,提早5d腐熟,水溶性NO3--N含量从71.41mg.kg-1增加到887.4mg.kg-1,C/N的降低有效促进了NH4＋-N向NO3--N的转化,加快了油枯堆肥化进程,有助于提高堆肥腐熟化程度,说明添加VT菌剂的堆肥腐熟效果相对显著。     

Succession and phylogenetic profile of eukaryotic communities in the composting process of rice straw estimated by PCR-DGGE analysis

The succession and phylogenetic profile of eukaryotic communities during the composting process of rice straw (RS) were studied by applying polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis followed by sequencing of 18S rDNA. Principal component analysis and cluster analysis of the DGGE band patterns of eukaryotic communities resulted in exactly the same grouping as found with phospholipid fatty acid (PLFA) analysis (Cahyani et al. in Soil Sci Plant Nutr 48:735, 2002) and by the DGGE pattern analysis of the bacterial communities (Cahyani et al. in Soil Sci Plant Nutr 49:619, 2003) for the same samples, namely the communities characterizing the pre-composting stage (initial RS materials), and thermophilic, middle, and curing stages of the compost. Different eukaryotic members characterized the respective stages as follows: fungi (Ascomycota) for the initial RS materials, protozoans (Apicomplexa) as well as the fungi (Ascomycota) of the initial RS materials for the thermophilic stage, fungi (Ascomycota and Basidiomycota), protozoans (Opalozoa, Ciliophora and Leptomyxida), nematodes and stramenopiles for the middle stage, and fungi (Ascomycota, Zygomycota and Oomycota), algae (Haptophyceae and Chrysophyceae), and nematodes for the curing stage, respectively. Temperature, moisture content, and substrates available seemed to play a key role in determining the composition of eukaryotic members present at the respective stages of the composting process of RS.     

微生物响应PBAT-PLA生物降解膜袋工业需氧堆肥降解机制

塑料污染已对全球环境造成严重威胁,生物降解塑料的推广使用及其工业堆肥是治理塑料污染的有效途径之一。该研究根据标准GB/T 19277.1-2011,在（58±2）℃的特殊高温条件下,对PBAT-PLA生物降解膜袋进行有氧堆肥降解,并选择微晶纤维素作为对照。通过对堆肥中的微生物进行16S/18S高通量测序,分析降解过程中细菌/真菌的群落种类和数量变化,包括物种多样性、物种组成、物种差异分析、样本比较分析,并结合扫描电镜下的微观形貌,深入探寻可降解塑料膜袋在工业需氧堆肥过程中的微生物响应降解机制。结果表明：微晶纤维素和生物降解膜袋在降解活跃期（第140天取样）,其所在堆肥中大量存在的优势菌属为Sphaerobacter（球杆菌属,放线菌纲）,分别占比20.25%和39.44%。与同样条件下不含降解材料的对照组堆肥相比,微晶纤维素/生物降解膜袋工业需氧堆肥降解过程中显著增长的4种菌属中有3种属于放线菌,说明放线菌对聚酯物的解聚以及纤维素的降解具有积极的作用。试验结果也表明了聚酯和纤维素的完整生物降解过程不依赖单一菌种,而是微生物协同作用的结果。     

菌剂DF-1对啤酒厂污泥与鸡粪堆肥的影响

为了探讨功能性菌剂对堆肥化进程的影响,并为加快啤酒厂污泥与鸡粪堆肥化进程和减少臭气提供理论依据,将自制菌剂DF-1接种至啤酒厂污泥与鸡粪的堆体中,以不接种堆体为参照,测定了堆肥化过程中各参数的变化及菌剂DF-1中优势微生物变化情况。结果显示：两个堆体废气中NH3浓度均呈现先上升后下降的变化趋势,H2S浓度则呈现持续下降的变化情形;不接种堆体NH3浓度至堆肥腐熟期仍为0.39 mmol/m3,而接种堆体第10天为1.25 mmol/m3,此后无法检出;不接种堆体中H2S浓度在堆肥第22天仍为0.7 mg/L;而接种菌剂堆体第10天为0.48 mg/L,此后无法检出。接种菌剂DF-1不但能降低堆体水分含量,而且其堆体腐熟期TN含量高于未接种菌剂DF-1的堆体,说明接种菌剂后不但能有效减少臭气,而且有利于堆肥产品后期烘干制粒和优质高效有机肥的产生。菌剂DF-1中优势菌种乳酸乳球菌、热带假丝酵母及绿色木霉在堆肥过程中存在交替演变。     

PLFA法和DGGE法分析堆肥细菌群落变化

同时采用PLFA（Phospholipid fatty acid）谱图分析法和DGGE（Denaturing gradient gel electrophoresis）法分析农业废物堆肥化过程中细菌群落的变化。结果表明：（1）单体PLFA数据显示样品之间的群落结构有明显差异,随着堆肥进程的进行,群落在不断演替,PLFA数据可以较为明确地表征微生物生物量的变化,但不能给出具体的物种变化信息;（2）DGGE分析显示堆肥过程中的样点和DGGE条带数据都存在3大主要类别,堆肥过程中细菌群落结构至少经历了3个阶段的演替,即嗜温细菌群落、高温细菌群落和腐熟期细菌群落。堆肥过程是微生物群落结构与堆肥温度相互制约的过程;（3）虽然两类方法显示的信息并不完全一致,但也因此说明了不同方法显示的信息并不是绝对的,采用各类方法组合研究堆肥微生物的信息变化是很有必要的。