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1.
【目的】二次发酵是实现鸡粪等养殖废弃物功能价值提高的关键阶段,本研究旨在将前期筛选得到的真菌应用于鸡粪堆肥的二次发酵阶段,探讨其促进二次发酵的效果并对其进行鉴定,为今后鸡粪的高值化与资源化利用提供理论依据和支撑。【方法】以鸡粪一次发酵产物为原料,添加实验室前期筛选的2株真菌(分别为FCM1和FCM3)进行二次发酵试验。共设置3个处理,分别为对照CK:原料中加入1%(体积L∶干物质量kg)无菌液体培养基;F1:原料中加入1% FCM1菌液;F3:原料中加入1% FCM3菌液。在二次发酵的不同时期,分析测定堆体温度、pH、电导率(EC)、铵态氮、硝态氮、种子发芽指数以及腐殖酸等指标。【结果】与对照相比,添加真菌主要促进了二次发酵阶段快速升温和腐殖化过程快速进行。与未接菌处理相比,真菌FCM3使堆料提前8 d进入升温期,真菌FCM1效果不佳,且在一定程度上延后了鸡粪堆肥的二次发酵。F3处理高温阶段(>50℃)持续了13 d,堆料的GI比对照处理提前25 d达到80%,且腐殖化程度较高(PHA=74.58%,PHA:胡敏酸/总腐殖酸)。相关分析表明,GI与pH、PHA显著正相关,与EC显著负相关。经形态和ITS rDNA测序等方法鉴定,FCM3为链格孢菌。【结论】真菌FCM3能够在一定程度上促进鸡粪堆肥二次发酵的进行,提高堆料的腐殖化程度。  相似文献   
2.
辅料及微生物菌剂对羊粪好氧堆肥腐熟度的影响   总被引:2,自引:0,他引:2  
好氧堆肥是目前有效的羊粪资源化利用方式,本研究旨在探究辅料及微生物菌剂对羊粪好氧堆肥腐熟度的影响。以羊粪、水稻秸秆、菌糠为堆肥原料,加入外源菌剂,检测各个处理的理化指标,生物学指标和重金属指标。平均温度Z4>Z3>Z2>Z1,最高温度68.1℃,69.1℃,69.3℃,71.1℃。pH先升高再降低,堆肥结束为8.53、8.25、8.43、8.35。C/N逐渐降低,堆肥结束为15、16、15和14。含水率逐渐下降,堆肥结束Z2含水率最低并且下降最多,为66.82%。全钾含量逐渐升高,Z4增加最大为196.58%。GI逐渐升高,50天均达到110%,Z4最先达到。NH4+-N含量波动下降。重金属含量均未超过国家标准NY 525—2012。以水稻为辅料与羊粪的堆肥效果优于菌糠,混合菌与菌糠处理提前进入高温期,更有利于羊粪堆体的快速腐熟。  相似文献   
3.
传统沼气工程的气肥联产工艺中,厌氧发酵产气与好氧发酵产肥互相独立,产气和产肥周期均较长、有机肥品质差,影响工程的高效运行。为缩短发酵周期、提高产气效率和有机肥品质,该研究将猪粪、鸡粪和秸秆混合进行15和30 d的干法厌氧发酵,将得到的沼渣添加秸秆辅料混合,分别设置65%和70%的发酵物料初始含水率进行15 d的高温好氧发酵,对比分析了不同厌氧-好氧发酵组合对产气和产肥的影响。结果表明:厌氧发酵阶段,混合物料的日产气率自发酵开始后逐渐上升,并在第8天达到最高峰,至第15天降至峰值的50%以下,此时累积产气量达到30 d发酵周期的71%,平均容积产气率达到1.91 m~3/(m~3?d),比发酵30 d平均容积产气率高41.5%。好氧发酵阶段,各处理组碳元素含量持续下降,氮元素含量先下降后增加,所得发酵产物均达到腐熟标准。采用15 d厌氧发酵所获得的沼渣进行好氧发酵,所得发酵产物的电导率、腐殖化程度和发芽指数均优于采用30 d厌氧发酵所获得的沼渣进行好氧发酵所得的发酵产物,同时总有机碳和总氮含量也较其分别提高了6.0%~21.7%和3.0%~10.2%,不同好氧发酵物料初始含水率对发酵产物的品质影响较不明显。因此,采用厌氧、好氧发酵周期均为15 d的组合,可缩短发酵周期、大幅提高产气效率和发酵产物的碳氮营养元素含量,有利于提高沼气工程运行效率和经济效益。  相似文献   
4.
5.
Enhancing the aerobic stability of silage is very important in silage production. The objective of this study was to compare the roles of a new bacterial strain Lactobacillus parafarraginis ZH1 with Lactobacillus plantarum Chikuso‐1 (LP) and Lactobacillus buchneri NCIMB 40788 (LB) in improving the aerobic stability of oat silage and identify the anti‐yeast substances produced by them. After ensiled for 45 days, either inoculated silages or control silage were of pH values lower than 4.2. The control and LP inoculated silage had poorer aerobic stability than LB and ZH1 inoculated ones (< 0.05). ZH1 inoculated silage produced more acetic acid, benzoic acid and hexadecanoic acid than LB inoculated one and had the best aerobic stability (< 0.05). In MRS medium, strain ZH1 produced more hexadecanoic acid than LP and LB strains, more benzoic acid than strain LP (< 0.05), and the equal amount of benzoic acid to LB (p > 0.05). In addition, benzoic acid and hexadecanoic acid had low minimal inhibitory concentrations to target yeasts in the pure culture. In conclusion, L. parafarraginis ZH1 had stronger anti‐yeast potential and more effectively improved the aerobic stability of silage than other strains used in this study.  相似文献   
6.
Aerobic rice technology is still new in Malaysia, and information regarding MARDI Aerob 1 (MA1), the first local aerobic rice variety, is still lacking. Therefore, comparative studies were carried out to determine the physiological performance of aerobic rice variety MA1 and lowland rice variety MR253 under water stress given at the panicle initiation, flowering and ripening stages. This experiment was arranged in a randomized complete block design. Stomatal conductance (gs), chlorophyll a fluorescence (Fv/Fm), leaf relative water content (leaf RWC), and soil moisture content (SMC) as well as yield component parameters such as panicle number, grain yield and 100-grain weight were measured. Results revealed that gs and leaf RWC for both varieties decreased with depletion of SMC. The correlation study between the physiological parameters and SMC indicated that Fv/Fm was not affected by water stress, regardless of varieties. The yield components (panicle number, grain yield and 100-grain weight) for both varieties greatly decreased when water stress was imposed at the panicle initiation stage. This study showed that the panicle initiation period was the most sensitive stage to water stress that contributed to a substantial reduction in yield for both varieties. Under the aerobic condition (control), MR253 produced higher panicle number, 100-grain weight and yield than MA1. Although MR253 is bred for lowland, it is well adapted to aerobic condition.  相似文献   
7.
The potential for using the composting process to sanitize plant waste infected with one of three plant pathogens was investigated using bench‐scale composting equipment. Two of these pathogens, the potato wart disease fungus Synchytrium endobioticum and Potato spindle tuber viroid (PSTVd) are currently subject to European quarantine regulations. The third, Polymyxa betae, a parasite of sugar beet, is regulated in some European countries when in association with Beet necrotic yellow vein virus (BNYVV), the causal organism of rhizomania disease of sugar beet. Survival of test organisms following various combinations of compost temperature, exposure time and moisture was determined using RNA‐based detection methodology and/or plant‐based bioassays. Mathematically definable relationships between compost treatment (temperature/time) and organism viability were identified for P. betae and S. endobioticum; these give some indication of the practicality of using composting for dealing with infected wastes. However, for PSTVd, the considerable variability in measured susceptibility of the viroid to the composting process meant that no such definable relationship could be determined and further work would be needed to extrapolate to practical situations.  相似文献   
8.
堆肥中不同氮素原位固定剂的综合比较研究   总被引:3,自引:0,他引:3  
为综合比较磷酸+氧化镁(PMO)、过磷酸钙(SP)和磷酸(PA)等3种氮素原位固定剂在堆肥化过程中对氮素损失控制、温室气体排放、堆肥品质以及成本的差异,进而选择合适的氮素原位固定剂,试验以猪粪和玉米秸秆为原料,采用强制通风模式(通风率均为0.25 L·kg~(-1)DW·min-1),在60 L发酵罐中进行模拟堆肥。结果表明,PMO处理能降低55.4%的NH3排放,但对N2O和CH4排放无显著影响;PMO堆肥产品充分腐熟,最终产品的晶体中鸟粪石相对含量达到78.3%。SP处理能降低37.5%的NH3和76.4%的CH4排放,对N2O无显著影响;氮素主要以氨氮形式固定。SP处理的成本最低,计算固定营养元素的价值后可实现利润4.0元·t-1。PA的NH3挥发率最低,仅为初始总氮的12.4%,但因氨氮积累导致堆肥未能彻底腐熟。鸟粪石沉淀技术是控制堆肥化过程中氮素损失的重要技术,在未来的研究中应当寻找磷酸的替代材料,以降低该技术的成本。  相似文献   
9.
典型畜禽粪便配伍食用菌菌渣堆肥研究   总被引:5,自引:0,他引:5  
研究3种典型畜禽粪便工厂化高温好氧堆肥过程中物理化学参数的动态变化规律,为典型禽畜粪便和食用菌菌渣废弃物有机肥料化提供理论依据。本研究分别以新鲜牛粪、猪粪和鸡粪配以2倍质量(DW)的食用菌菌渣进行堆肥试验,研究堆肥过程中温度、pH值、铵态氮、硝态氮和发芽指数等理化指标的动态变化规律。结果表明:堆肥过程中牛粪、鸡粪和猪粪处理在55℃以上的持续时间均超过15天,堆体温度均超过70℃。堆肥结束时,猪粪、鸡粪、牛粪处理的pH值分别为pH 7.59、7.81、7.48,符合腐熟堆肥pH 5.5~8.5的一般标准,种子发芽指数(GI)均大于80%,总养分(N+P_2O_5+K_2O)分别为4.31%、5.01%、4.57%,只有鸡粪处理满足有机肥养分标准(NY 525—2012)。堆肥过程中各处理铵态氮含量逐渐下降,硝态氮含量逐渐增加,至堆肥结束时牛粪、鸡粪和猪粪处理铵态氮的减少量分别为45.6%、29.2%、33.9%,而相应地硝态氮含量分别增加到2.59、2.57、2.15 g/kg。本研究结果可为适度规模养殖场的畜禽粪便进行堆肥处理提供一定的理论依据。  相似文献   
10.
The study was designed to assess the seasonal variations in the quality and lipid profile of mussel meat (Mytilus galloprovincialis) harvested along the Bulgarian coast of the Black Sea. The trial period lasted from June to October, and the sampling was carried out in the area of Varna Bay. Technological quality of the mussels was determined by measuring the water holding capacity (WHC) and cooking and roasting losses. Proximate composition, total aerobic plate count, and fatty acid analysis were carried out. Technological parameters and nutritional quality of the mussel meat were strongly affected by the season. During the summer, the mussels had higher mass, meat content, and meat yield (< 0.001) compared to the early autumn, which corresponds to the lowest protein content during this season. Lipid profile showed seasonal variations in both individual and total fatty acid amounts (p < 0.001). Saturated fatty acids (SFA) had the highest content in summer, while monounsaturated fatty acids (MUFA) decreased gradually until the autumn. The content of polyunsaturated fatty acids (PUFA) reached its peak in October, contributing to the most favorable values of the nutritional indices of lipids in the early autumn.  相似文献   
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