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121.
微生物菌剂对兰州城市生活污泥堆肥效果的影响 总被引:1,自引:0,他引:1
以兰州市城市生活鲜污泥和40%干污泥为原料,以玉米秸秆为辅料,添加金宝贝生物发酵剂和阿姆斯生物发酵剂进行堆肥,研究微生物菌剂对堆肥过程中温度、含水率、NH4+ N、NO3- N和全N的影响。结果表明,除鲜污泥(D 1,CK)处理外,其他各处理堆体温度保持在50 ℃以上均超过7 d,达到堆肥卫生标准,加入微生物菌剂使堆体提前5 d达到50 ℃;其他各处理经过20 d堆置含水率降至45%以下,达到园林绿化使用标准;加入微生物菌剂使堆体全N损失增加0.56%~4.47%,并促进NH4+ N的生成和NO3- N的积累。 相似文献
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Ko-ichi OSHIMAN 《Journal of General Plant Pathology》2000,66(3):258-263
Pretreatment with sodium alginate (20 g/m2) prior to application of a biocontrol agent, Pseudomonas fluorescens strain A11RN, enhanced the control turfgrass snow mold caused by Typhula ishikariensis biotype B. Disease severities in two fields relative to untreated control plots were 53% and 61% in plots treated with both
the strain and sodium alginate, which were significantly lower than 69% and 77% in plots treated only with the strain. The
antagonist population remained above the threshold for effective control (ca. 1×107 cfu/cm3) at least for the first month under snow in pretreatment with sodium alginate. The population of the biocontrol agent after
snowmelt on turfgrass was five times higher in sodium alginate-amended plots than in unamended plots. Sodium alginate alone
did not reduce disease severity. Sodium alginate might have supported the survival of the applied strain.
Received 7 June 1999/ Accepted in revised form 20 December 1999 相似文献
124.
介绍了娄底市第一污水处理厂一期工程设计概况和采用的改良型氧化沟脱氮除磷工艺,分析了该污水处理厂调试、培菌过程中出现的问题,并针对性地采取了一系列改进措施.在进水远低于设计值的不利条件下,通过合理培菌,不到一个月系统启动成功.监测结果表明:该工艺运行可靠,出水水质稳定、达标. 相似文献
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Conservation tillage has proved to be an effective option to reduce erosion and particulate phosphorus (PP) losses from fields to watercourses. However, it usually leads to the higher losses of P in dissolved reactive (DRP) form if P accumulates into the uppermost soil layer.In this study we investigated the influence of CaCO3-rich boardmill sludge (BMS, applied 7 years ago) on soil properties and percolate quality with soil samples as well as undisturbed soil columns taken from a long-term conservation-tilled clay field experiment. A short-term laboratory experiment was undertaken to evaluate whether newly added BMS (FS) can be used to improve the quality of percolate waters by reducing turbidity, PP and DRP.The hypothesis was that BMS reduces the risk of dissolved reactive phosphorus (DRP) leaching from conservation-tilled soil. BMS served as a liming agent and counteracted the no-till-induced acidification and accumulation of DRP in the surface soil layer. Surface soil pH was on average 0.3 units higher and soil Ca 500 mg kg−1 higher in the BMS-treated plots than in the plots without BMS. The ability of BMS to enhance the availability of P for plants may prevent the surface accumulation of P in NT cultivation. At the same time, BMS-induced increase in Ca and EC of the surface soil suppress the diffuse double layer by reducing P desorption and leaching risk.In the laboratory experiment, FS reduced percolate turbidity by 80% and PP and DRP concentrations by 62% and 50%, respectively. FS probably improved stability of soil aggregates in the laboratory experiment, obviously through enhanced microbial activity. The covering effect and infiltration of water through the 0–5 cm soil layer seemed to be crucial factors in reducing P losses.BMS proved to be a promising material for the applications to the conservation-tilled fields. The effect of BMS on microbes and immobilization of nutrients, should, however, be studied further in fields under a wider diversity of conditions. 相似文献
127.
Abstract. Restoration of landfill sites to a vegetated after-use is severely compromised if soil-forming materials (SFMs) have to be used as substitute growing media for the restoration cap, owing partly to their poorly-developed structure. The effects of crushed brick material (brick), composted green-waste organic matter (OM) and potassium chloride salt (KCl) in a clay SFM were assessed at the Brogborough Landfill Site (Shank Group plc) in the county of Bedfordshire, UK. Soil structure was characterized three times in a two-year experimental period through measuring drainage water release and aggregate stability and size distribution. Crushed brick and composted OM at 100 t ha−1 improved the ability of the clay to release water by drainage. In addition, the composted OM was associated with an increase in the size of stable aggregates, whereas the brick amendment reduced the overall aggregate stability. The KCl amendment had no consistent effect. Some beneficial structural improvements were thus associated with the brick and OM amendments, although these were rarely significant at the 5% level and the effects declined over time in the absence of vegetation and re-application. Nevertheless, incorporation of crushed brick and organic amendments may offer a potential structure-improving option in clay SFMs prior to vegetation establishment. 相似文献
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