生活垃圾堆肥过程中有机态氮形态的动态变化

利用接种不同外源微生物进行城市生活垃圾的堆肥试验,研究在堆肥过程中不同形态有机态氮组分的变化规律。结果表明,随着堆肥的进行,全氮与酸水解性氮含量均呈下降的趋势,其中外源微生物处理能加速全氮与酸水解性氮含量的降低,但至堆肥结束时,与不加外源微生物处理相比,并没有引起氮素的损失。氨基酸态氮含量则呈现先降低后增加的趋势,堆肥结束时,外源微生物处理氨基酸态氮含量明显高于不加微生物处理,表明外源微生物处理可促进氨基酸态的形成;酰胺态氮与氨基糖态氮含量有相同的变化趋势,各处理都是在堆肥的升温期、高温期增加,随着堆肥温度的下降而降低,在堆肥的腐熟阶段,则呈现较为平稳的走势。但相对于堆肥的不同时期,由于处理不同,酰胺态氮与氨基糖态氮含量有明显的差异,其中外源微生物处理酰胺态氮含量明显低于不加微生物处理,而氨基糖态氮则相反。     

接种微生物条件下牛粪＋麦秸堆腐过程有机组分的动态变化

大量排放的畜禽粪便若利用不当则会对环境构成威胁,经微生物发酵、制成高效有机肥料是粪肥与秸秆综合利用的一种重要方式。试验以牛粪添加不同比例的小麦秸秆为原料,在接种和非接种微生物的条件下进行堆腐,研究了腐解过程有机组分及腐殖物质的动态变化。结果表明,随着腐解进行,乙醇溶性组分含量逐渐降低;水溶性组分含量先升高再降低;半纤维素和纤维素含量随腐解进行呈现一定波动,但总体呈降低趋势;木质素含量呈增加趋势;全碳含量降低,腐殖物质碳占全碳的比例逐渐增加,H/F比值逐渐升高。秸秆的加入比例越高越有利于木质素的积累,牛粪所占比例越大则越有利于腐殖物质的形成。接种微生物可促进有机物料中各有机组分的分解,并有利于腐殖物质的形成。     

堆肥反应器中硫磺对牛粪好氧堆肥的保氮效果研究

利用堆肥反应器严格控制堆肥条件,以牛粪和蘑菇渣为原料进行好氧堆肥,在堆肥过程中添加硫磺粉,研究硫磺对堆肥温度、pH、氮素转化、硫素转化和保氮效果的影响。结果表明,堆肥中添加0.5%硫磺粉（T1）对堆肥温度没有显著影响,高温期（≥50℃）维持5.5 d; 而添加1.0%硫磺粉(T2)能快速升温,但堆肥高温期维持时间4.6 d。添加不同量的硫磺粉均能显著降低堆肥pH,与CK比较差异显著。添加硫磺粉能大幅度增加铵态氮含量,至堆肥结束时,T1和T2处理铵态氮含量分别是CK处理的15倍和24倍,差异极显著; 还增加了堆肥有效硫含量,至堆肥结束T1和T2有效硫含量分别较堆肥初始增加35.7%和77.1%。整个堆肥过程总氮（TN）含量呈增加的趋势,堆肥结束时CK、T1和T2处理的TN含量分别达15.8、16.5和16.9 g/kg,T1和T2分别比CK处理增加4.4%和7.0%。说明在牛粪好氧堆肥中添加0.5%或1.0%硫磺粉,均可起到一定的保氮作用,可大幅度提高堆肥铵态氮和有效硫的含量,改善了堆肥养分品质; 而且添加1.0%硫磺粉效果好于0.5%硫磺粉。但是添加1.0%硫磺粉缩短了堆肥高温期,降低了种子发芽指数,不利于堆肥的无害化进程。     

堆肥反应器中表面活性剂APG对牛粪堆肥酶活性的影响

利用堆肥反应器严格控制堆肥条件, 以牛粪为主要原料进行好氧堆肥, 在堆肥过程中加入表面活性剂烷基多糖苷(APG), 研究其对堆肥中微生物数量以及酶活性变化的影响。结果表明: 在好氧堆肥中添加表面活性剂APG对堆肥中的微生物无显著抑制作用, 微生物数量无显著变化(P>0.05); 但可以促进堆肥升温, 延长高温期。加入APG对堆肥中的过氧化氢酶活性几乎无影响, 最终APG处理和CK处理的酶活性值均达到1.17 mmol·g^-1左右; 加入APG后脲酶活性略有提高, 第2 d APG处理和CK处理的脲酶活性均达到峰值, 分别为32.15 mg(NH₃-N)·g^-1·24h^-1和30.17 mg(NH₃-N)·g^-1·24h^-1, 差异不显著(P>0.05), 第7 d达到最低值, 分别为0.81 mg(NH₃-N)·g^-1·24h^-1和0.38 mg(NH₃-N)·g^-1·24h^-1, 差异显著(P<0.05); APG处理对转化酶和纤维素酶活性均有明显的提高作用, 其中转化酶在第3 d加APG处理和CK处理峰值分别为18.15 mg(葡萄糖)·g^-1·24h^-1和11.77 mg(葡萄糖)·g^-1·24h^-1, 第21 d两处理峰值分别为24.09 mg(葡萄糖)·g^-1·24h^-1和20.71 mg(葡萄糖)·g^-1·24h^-1, 差异显著(P<0.05); 纤维素酶在第3 d加APG处理和CK处理峰值分别为58.77 mg·min^-1和30.62 mg·min^-1, 差异显著(P<0.05)。本试验结果表明, 添加表面活性剂APG可以提高堆肥中转化酶和纤维素酶活性, 促进堆肥中有机物质的转化, 一定程度上加快好氧堆肥进程。     

添加微生物菌剂对牛粪高温堆肥腐熟的影响

通过向堆肥中添加微生物菌剂和腐熟堆肥研究了其对堆肥腐熟速度的影响。结果表明,添加菌剂和腐熟堆肥在堆制初期均能促进堆体快速升温,较对照提前1～4d到达高温阶段(＞50℃),且菌剂添加量越大,升温越快;与对照相比,添加600mg·kg~(-1)菌剂和50g·kg~(-1)腐熟堆肥使高温期(＞50℃)延长了3～4d。堆制29d后,添加600 mg·kg~(-1)菌剂和50 g·kg~(-1)腐熟堆肥的处理均较好腐熟,种子发芽指数分别为92．1％和84．4％,其他处理则未达到腐熟。这表明向堆肥中接人一定量的菌剂和腐熟堆肥均可加快堆肥腐熟,缩短堆肥周期。     

添加微生物菌剂对牛粪高温堆肥腐熟的影响

通过向堆肥中添加微生物菌剂和腐熟堆肥研究了其对堆肥腐熟速度的影响。结果表明,添加菌剂和腐熟堆肥在堆制初期均能促进堆体快速升温,较对照提前1～4d到达高温阶段（>50℃）,且菌剂添加量越大,升温越快;与对照相比,添加600mg·kg^-1菌剂和50g·kg^-1腐熟堆肥使高温期（>50℃）延长了3～4d。堆制29d后,添加600 mg·kg^-1菌剂和50 g·kg^-1腐熟堆肥的处理均较好腐熟,种子发芽指数分别为92.1%和84.4%,其他处理则未达到腐熟。这表明向堆肥中接入一定量的菌剂和腐熟堆肥均可加快堆肥腐熟,缩短堆肥周期。     

低温下复合发酵剂对牛粪与鸡粪混合堆肥有机氮变化的影响

从低温条件下牛粪、鸡粪混合堆肥过程中有机氮组分变化入手,研究接种不同的复合发酵剂对堆肥有机氮素形态转化的影响.结果表明,各处理全氮、酸水解有机氮、氨基酸态氮含量均呈先降低后升高的趋势;堆肥结束时接种复合发酵剂的处理全氮量较不接种的对照提高30.81%;接种含纤维素分解菌发酵剂的处理全氮量较接种复合发酵剂的处理提高6.54%.表明接种含纤维素分解菌的复合发酵剂能有效减少堆肥氮损失,提高产品肥效.     

外源微生物对堆肥理化性质及酶活影响的研究

利用牛粪和稻草为原料进行堆肥实验,通过测定堆肥过程中的温度、含水率等物理、化学指标以及酶活性的变化,研究了接种外源微生物对堆肥过程的影响。结果表明,接种外源微生物比对照提前2d达到高温期,并且维持时间长。大肠杆菌数量及植物毒性比不接种大幅度降低,纤维素酶、脲酶、多酚氧化酶、过氧化氢酶均有所增加。说明接种外源微生物可以使堆肥中微生物数量增多,加速堆料中有机物的分解,加快堆肥腐熟,缩短堆肥反应的进程,对优化堆肥工艺具有重要的意义。     

不同绿肥与牛粪混合堆腐过程中有机组分的动态变化

通过苜蓿、猫尾草、籽粒苋分别与牛粪混合堆腐进行改性处理,研究堆腐过程中有机组分的动态变化。结果表明,绿肥与牛粪混合堆腐可以使堆腐产物中水溶性有机组分的含量增加,提供更多的营养物质供作物直接吸收利用,并且显著提高了堆腐产物持续生成水溶性胡敏酸的能力,其中添加苜蓿堆腐处理产生的水溶性有机组分含量大于其它处理。添加苜蓿和猫尾草堆腐不但可以增加堆腐产物中碱溶性有机物和碱溶性胡敏酸的含量,提高堆腐产物的HA/FA值,而且在堆腐后期可以降低堆腐产物中碱溶性富里酸的减小,添加籽粒苋堆腐处理这种作用不明显。     

不同堆肥原料的有机无机复合肥对油菜生长及土壤供氮特性的影响

通过田间试验,研究了采用猪粪堆肥、中药渣堆肥和鸡粪堆肥为原料制成的有机无机复合肥与无机复合肥等氮量施入对油菜产量、氮素利用率、土壤供氮特征以及土壤微生物多样性的影响。结果表明:各施肥处理油菜籽产量均显著高于对照的油菜籽产量。与化肥处理比较,三种堆肥原料的有机无机复合肥的油菜籽产量显著高于化肥处理,较化肥增产12.7%～33.2%。各有机无机复合肥处理均能增加油菜单株有效角果数。三种有机无机复合肥处理均能显著促进油菜对氮素的吸收,从而提高了氮素利用率。与化肥处理和不施肥处理比较,三种堆肥原料的有机无机复合肥处理能够明显提高土壤有效态氮的含量,调节土壤氮素的释放速度。采用邻接法分析各处理土壤DNA条带表明:5个处理土壤样品的细菌群落共分为三大族群,化肥处理与对照处理为一种族群,中药渣处理为一种族群,猪粪处理和鸡粪处理属一种族群。说明施入外源有机物质(猪粪、鸡粪与中药渣)可能改变土壤的细菌群落结构,而施入化肥对土壤的细菌群落结构影响较小。     

除氨菌系对牛粪堆肥氮素转化的影响

为了减轻牛粪堆肥过程中NH3释放对环境的污染及氮素损失,在牛粪堆肥时添加除氨菌系,研究其对氮素形态转化的影响。加除氨菌系处理的NH4+-N、NH3较对照分别降低20.47%和61.21%,全氮、NO3--N较对照分别提高11.63%和65.01%,酸解有机氮、氨基酸态氮、酰胺态氮和氨基糖态氮含量分别提高12.42%、11.26%、16.92%和19.51%。表明除氨菌系在牛粪堆肥过程中,能够固定NH4+-N向有机氮各组分转化,减少NH3挥发,具有较好的保氮作用。     

不同堆肥方式对奶牛粪便处理效果的试验研究

以奶牛粪便为原料，进行了堆肥槽、露天条垛和接种外源微生物的对比试验。结果表明：与露天条垛堆肥相比较，堆肥槽能节省50%以上土地，并可防止二次污染；露天条垛堆体温度升高至50℃比槽式堆体提前了3d；接种外源微生物制剂堆体升温至50℃比未接种的提前2～3d；本试验中各处理的种子发芽指数变化表明，牛粪经过20d堆肥处理后就对植物无毒性。     

不同堆肥方式对奶牛粪便处理效果的试验研究

以奶牛粪便为原料,进行了堆肥槽、露天条垛和接种外源微生物的对比试验。结果表明:与露天条垛堆肥相比较,堆肥槽能节省50％以上土地,并可防止二次污染;露天条垛堆体温度升高至50℃比槽式堆体提前了3d;接种外源微生物制剂堆体升温至50℃比未接种的提前2～3d;本试验中各处理的种子发芽指数变化表明,牛粪经过20d堆肥处理后就对植物无毒性。     

鸡粪堆肥中氮转化微生物变化特征的初步研究

采用室外人工翻堆好氧堆肥方法,进行了70d的鸡粪、鸡粪添加1%稻草和鸡粪添加3%稻草堆肥试验,采用平板记数法和最大可能记数法(MPN),研究了堆肥过程中氨化细菌、固氮菌、硝化菌和反硝化菌的数量变化规律。结果表明:氨化作用在堆肥初期显著,硝化作用、反硝化作用、硝化细菌和反硝化细菌数量随堆肥时间的推移有上升的趋势;堆肥中存在固氮菌,但数量变化不大。堆肥中氮转化微生物变化特征与堆肥中铵态氮、硝态氮变化规律相一致。     

Effect of nitrite accumulation on nitrous oxide emission and total nitrogen loss during swine manure composting

The present study investigated the nitrogen balance in swine manure composting to evaluate the effect of nitrite (     ) accumulation, which induces nitrogenous emissions, such as N₂O, during compost maturation. During active composting, most N losses result from NH₃ emission, which was 9.5% of the initial total nitrogen (TN_initial), after which,     began to accumulate as only ammonia-oxidizing bacteria proliferated. After active composting, the addition of mature swine compost (MSC), including nitrite-oxidizing bacteria (NOB), could prevent     accumulation and reduce N₂O emission by 70% compared with the control in which     accumulated as a result of delayed growth of indigenous NOB. Total N₂O emissions in the control and in the treatment of MSC addition (MA) were 9.3% and 3.0% of TN_initial, respectively, whereas N losses as the sum total of NH₃ and N₂O over the whole period were 19.0% (control) and 12.8% (MA) of TN_initial, respectively. However, the difference in total N losses was markedly greater than that measured as NH₃ and N₂O, which were 27.8% (control) and 13.3% (MA) of TN_initial, respectively. These results demonstrated that the magnitude of nitrogen losses induced by     accumulation is too large to ignore in the composting of swine manure.     

Increased total nitrogen content of poultry manure by decreasing water content through composting processes

Microbial mineralization of urea and uric acid in poultry litter can lead to loss of nitrogen (N) content and its value as a fertilizer. To minimize the loss of N in the composting processes, controlling the water content in litters is a key to reduce the mineralization processes of N compounds. The N content of litter may be influenced by diets, hen age and the type of poultry houses used. The objectives of the present study were i) to determine the relationship between the water content and the decomposition rate of uric acid in poultry litter and ii) to investigate the effect of hen age and crude protein (CP) percentages in diets on the N content of poultry litter. A layer feeding trial was conducted in two poultry farms with windowless and open-floor houses. An incubation study of poultry litter was performed under different levels of water content. Our study found that the diet CP percentage (16.5–18%) and the growth stage of laying hens did not have a significant effect on the amount of total N (52–56?g?kg^?1) and uric acid-N (26–31g?kg^?1) in fresh litters. At the 7^th day of litter incubation study, the concentration of uric acid-N was 22 g kg^?1 in litters with a water content of 35%, whereas it further decreased to less than 1.3 g kg^?1 in litters with a water content of 55% and higher levels. The decomposition rate of uric acid-N in litter was 0.3–3.1g?kg^?1?day^?1 in the windowless house and 3.1–7.1g?kg^?1?day^?1 in the open-floor house. Decomposition of uric acid in litters was positively correlated to the litter moisture content that is controlled to be lower in windowless houses (40–50%) than in open-floor houses (55–80%) during the composting period. Our study suggests that the use of windowless houses for layer chicken production is effective for producing poultry manure with a high N content.     

Nitrate leaching from an organic dairy crop rotation: the effects of manure type, nitrogen input and improved crop rotation

Abstract. Four management systems combining high and low livestock densities (0.7 and 1.4 livestock units ha⁻¹) and different types of organic manure (slurry and straw based FYM) were applied to an organic dairy crop rotation (undersown barley – grass–clover – grass–clover – barley/pea – oats – fodder beet) between 1998 and 2001. The effects of the management systems on crop yields and nitrate leaching were measured. In all four years, nitrate leaching, as determined using ceramic suction cups, was higher in the three crops following ploughing of grass–clover than under the barley or grass–clover. Overall, no significant differences in nitrate leaching were observed between the management systems. However, the replacement of the winter wheat crop used in the earlier experimental period (1994–97) by spring oats with catch crops in both the preceding and succeeding winters reduced nitrate leaching compared with the earlier rotation. Increasing the livestock density, which increased manure application by c. 60 kg total N ha⁻¹, increased crop yields by 7 and 9% on average for FYM and slurry, respectively. Yields were 3–5% lower where FYM was used instead of slurry. The experiment confirmed the overriding importance of grassland N management, particularly the cultivation of the ley, in organic dairy crop rotations.