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991.
不同碳氮比下牛粪高温堆肥腐熟进程研究   总被引:9,自引:0,他引:9  
为有效处理奶牛场养殖粪污,建立以之为原料的牛粪有机肥高效堆肥工艺,本文通过工厂堆肥试验,以牛粪为主料,以蘑菇渣、稻壳为辅料,设置C/N=15、C/N=25、C/N=35三个处理,研究不同碳氮比原料高温堆肥过程中堆体温度、pH值、EC、C/N和养分等理化指标的变化。结果表明,C/N=25堆体达到的温度最高,达到最高温度所需时间最短且保持65℃以上时间最长。堆肥过程中各处理pH值变化基本一致,均是先升高后降低再升高最后趋于稳定,各处理EC都是先波动上升后在波动中逐渐下降并趋于稳定。各处理堆体在堆肥过程中,C/N也都呈现逐步减小的趋势,并最终保持稳定。至堆肥结束时,各处理C/N分别11.7、15.0和21.3。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,铵态氮的损失量分别为80.7%、36.6%和46.7%,硝态氮含量分别增加到0.61 g kg~(-1)、0.50 g kg~(-1)、0.41 g kg~(-1)。堆肥结束时,各处理胡敏酸类、富里酸类等物质成为DOM的主体部分,N1、N3处理发芽指数大于50%但小于85%,N2处理发芽指数大于85%。各处理堆肥全磷、全钾含量在堆肥结束时比堆肥初始均有所增加。因此,牛粪高温堆肥能有效处理奶牛场养殖废弃物,且C/N=25时堆肥效果最佳。  相似文献   
992.
利用食用菌菌渣生产有机肥料的研究   总被引:13,自引:0,他引:13  
无害化处理食用菌菌渣生产优质有机肥的试验研究表明,接种高温纤维菌可使堆内温度迅速上升至45℃以上,并可持续18~20 d。经过45 d堆制,接种菌剂的处理除水分含量外,总养分和有机质含量、pH值和外观形状等技术指标均达到有机肥料的标准(NY525-2002)。从发酵温度,持续时间,有机肥的养分含量和外观形态等方面看,接种高温纤维菌加猪粪处理食用菌菌渣的腐熟效果最好,可用于食用菌菌渣的无害化处理和资源化利用。  相似文献   
993.
选取稻草、油菜秸秆和食用菌渣作为猪粪堆肥的有机辅料,研究三种堆肥体系中氨气挥发释放规律及其影响因素。结果表明,经过65 d的堆腐,稻草-猪粪、油菜秸秆-猪粪和菌渣-猪粪堆肥氨气挥发量分别为5.084、6.483和3.013 g/kg,是对照(纯猪粪)处理(7.836g/kg)的64.88%、82.74%和38.45%。从氨气的释放量和释放速率看,菌渣是一种较好的有机辅料。从氨气释放的时间变化特征看,稻草对猪粪堆肥氨气排放高峰期影响最为明显,主要表现为氨气前期猛烈释放且持续时间短,是猪粪快速腐熟技术优选的高效有机辅料。堆腐完成后,三种有机辅料均能减少水溶性NH4+-N的累积,增加水溶性NO3--N的含量,引起pH和EC值下降,提高堆肥全氮含量,促进堆肥有机物和粗纤维的降解,且以稻草和菌渣处理效果最为显著。  相似文献   
994.
The fate of the insecticidal Cry1Ab protein from crop residues (leaves and roots) of the transgenic maize variety MON810 was studied in the presence and absence of two earthworm species (Lumbricus terrestris, Aporrectodea caliginosa; separate incubations) in soil microcosms. The recombinant Cry1Ab protein was quantified using a highly sensitive ELISA. Control microcosms received corresponding non-transgenic plant material. All earthworms survived in the microcosms over a period of 5 weeks, irrespective of whether they received MON810 or non-transgenic plant material. Weight loss was observed for both earthworm species, independent of the plant material or transgenic modification. A strong decline of immunoreactive Cry1Ab in plant residues (mean initial concentration approx. 5000 ng g−1) of MON810 was observed in all treatments, but in microcosms with earthworms this decline was significantly higher with less than 10% of the initial Cry1Ab concentration remaining after 5 weeks. Cry1Ab concentrations in casts were only 0.1% of those found in remaining plant material of the respective microcosms. No immunoreactive Cry1Ab proteins were found in earthworm tissues (threshold of detection: 0.58 ng g−1 fresh weight). No further decline was found for Cry1Ab concentrations in casts of A. caliginosa during a subsequent period of 3 months of incubation in bulk soil (<0.1 ng g−1) after removal of the earthworms from the microcosms, while in casts of L. terrestris the concentration decreased from 0.4 to below 0.1 ng g−1. In conclusion, this study demonstrates that earthworms enhance the decline of immunoreactive Cry1Ab proteins from maize residues.  相似文献   
995.
接种木质纤维素分解复合菌系对堆肥发酵进程的影响   总被引:4,自引:0,他引:4  
以具有高效木质纤维素分解能力的复合菌系作为接菌剂,接种到以牛粪、鸡粪和麦秸为材料的堆肥化过程中,测定了各发酵参数和物质成分的变化.利用变性梯度凝胶电泳(DGGE)和末端限制性片断多态性(T-RFLP)分析方法,研究了堆肥发酵过程中微生物群落的动态.结果表明,接菌对堆肥化过程中温度、水分和pH值的影响不大.经63 d发酵之后,接菌处理的半纤维素、纤维素和木质素的减重率比不接菌处理分别高4.3%、3.0%和3.4%.接菌处理的各个发酵阶段C/N比也明显低于不接菌处理.DGGE和T-RFLP的结果显示,接菌后堆肥发酵初期复合系中的 Ureibacillus thermosphaericu、Pseudoxanthomonas taiwanensis、Tepidiphilus margaritifer、Rhizobiaceae str.M100、C thermobutyricum 和Bacillus thermoamylovorans 菌株大量定殖于堆肥体系中,DGGE图谱中可见接种处理堆肥体系中的条带数少于不接菌处理,而同一水平线的条带亮度明显高于不接菌处理.DGGE和T-RFLP的结果都表明接菌处理的微生物多样性少于不接菌处理.可见接种微生物在堆肥体系中占据优势,抑制了部分杂菌生长,促进了发酵进程.  相似文献   
996.
The accumulation of heavy metals (HMs) in soils is the most often cited potential risk of compost application. As the ecological effects of metals are related to mobile fractions rather than to total concentrations in the soil, we measured the total (aqua regia–extractable) HM concentrations, the readily available water‐soluble and the potentially bioavailable LiCl‐extractable fraction of soil HMs in a field experiment after 10 y with total applications of 95, 175, and 255 t ha–1 biowaste compost (fresh matter). Total soil concentrations of Cd, Cr, Cu, Ni, and Pb in the compost treatments were not significantly higher than in the unfertilized control. Total Zn concentrations increased in the treatment with the highest application rate, as expected from the calculation of the Zn load in the composts. In the mobile fractions, as measured in soil saturation extract and LiCl extract, Cd and Pb were not detectable. Concentrations of Cr, Ni, and Zn were in the range published for unpolluted soils in other studies and did not show any differences according to treatment. Easily exchangeable Cu (in LiCl extract) was increased with compost fertilization, most probably due to complexation with low‐molecular organic complexants. Except for Cd and Zn, the results of the mobile HM fractions in the soil were in good agreement with plant HM concentrations. In conclusion, fertilization with high‐quality biowaste compost at such rates and after 10 y of application gives no cause for concern with regard to both total HM concentrations and available HM fractions.  相似文献   
997.
Phosphorus (P) fertilizers and mycorrhiza formation can both significantly improve the P supply of plants, but P fertilizers might inhibit mycorrhiza formation and change the microbial P cycling. To test the dimension and consequences of P fertilizer impacts under maize (Zea mays L.), three fertilizer treatments (1) triple superphosphate (TSP, 21–30 kg P ha?1 annually), biowaste compost (ORG, 30 Mg ha?1 wet weight every third year) and a combination of both (OMI) were compared to a non‐P‐fertilized control (C) in 2015 and 2016. The test site was a long‐term field experiment on a Stagnic Cambisol in Rostock (NE Germany). Soil microbial biomass P (Pmic) and soil enzyme activities involved in P mobilization (phosphatases and ß‐glucosidase), plant‐available P content (double lactate‐extract; PDL), mycorrhizal colonization, shoot biomass, and shoot P concentrations were determined. P deficiency led to decreased P immobilization in microbial biomass, but the maize growth was not affected. TSP application alone promoted the P uptake by the microbial biomass but reduced the mycorrhizal colonization of maize compared to the control by more than one third. Biowaste compost increased soil enzyme activities in the P cycling, increased Pmic and slightly decreased the mycorrhizal colonization of maize. Addition of TSP to biowaste compost increased the content of PDL in soil to the level of optimal plant supply. Single TSP supply decreased the ratio of PDL:Pmic to 1:1 from about 4:1 in the control. Decreased plant‐benefits from mycorrhizal symbiosis were assumed from decreased mycorrhizal colonization of maize with TSP supply. The undesirable side effects of TSP supply on the microbial P cycling can be alleviated by the use of compost. Thus, it can be concluded that the plant‐availability of P from soil amendments is controlled by the amendment‐specific microbial P cycling and, likely, P transfer to plants.  相似文献   
998.
通过蚯蚓堆肥试验,探讨菊糖对蚯蚓的益生作用及高活力蚯蚓粪肥的形成过程,可为滩涂生态农牧化模式构建及障碍土壤修复提供理论依据.以牛粪、赤子爱胜蚓(Eisenia fetida)和菊糖为材料,设置纯牛粪养殖蚯蚓(EM)和添加菊糖的牛粪养殖蚯蚓(IEM)处理,养殖周期为40 d,每隔10 d采样分析,研究了牛粪–蚯蚓肠道内容...  相似文献   
999.
通过温室土培盆栽试验,研究了重金属镉污染土壤上连作油菜及施用堆肥对土壤中镉赋存形态及牛物有效性的影响.结果表明:(1)在油菜连作体系下,施用堆肥显著降低油菜地上部镉含量.施用堆肥改变了土壤镉赋存形态,显著降低土壤易溶态和碳酸盐结合态镉含量而增加土壤铁锰氧化物结合态镉含量,从而降低土壤镉的生物有效性.(2)在相同堆肥处理下,种植两茬油菜后的土壤易溶态和碳酸盐结合态镉含量与不种植油菜的处理相比显著降低;而土壤硫化物及有机结合态镉含量较对照有所上升,种植油菜对土壤铁锰氧化物结合态镉和残渣态含量影响不显著,但是不同积累镉能力油菜朱苍花籽和川油Ⅱ-93之间对土壤镉形态的影响差异不显著.  相似文献   
1000.
板栗苞和牛粪混合堆肥的物质变化特性研究   总被引:9,自引:1,他引:8  
以板栗苞和牛粪为原料,在北京市密云板栗生态园中进行了为期40d的高温好氧堆肥.板栗苞取自密云水库库区板栗生态园,牛粪取自周边养牛场的奶牛粪便,初始混合物料C/N为25~30,含水量在55%~60%,采用人工翻堆的方法进行通风.结果表明,由于板栗苞与牛粪都是术质纤维素含量较高的物料,所以在堆制结束时.堆肥中的粗纤维含鼍仍有10.11%,整个过程中粗纤维降解率为57.25%.水溶性硝态氮在堆肥过程中总体呈上升趋势,而铵态氮损失比较严重,比初始物料减少了33.30%.在堆肥结束时,C/N基本稳定在20左右.在堆制20 d后,发芽指数(GI)已上升到了80%以上.说明板栗苞和牛粪堆肥40 d后基本可以达到腐熟,但堆肥中仍残存部分有形的板栗苞,需进一步采取措施促进板栗苞中木质纤维素的降解.  相似文献   
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