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高效纤维素分解菌在蔬菜-花卉秸秆联合好氧堆肥中的应用 总被引:14,自引:0,他引:14
以滇池流域典型的蔬菜废物和花卉秸秆为堆肥原料,以本实验室筛选、保存的17株纤维素降解菌和1株购买的产黄纤维单胞菌(Cellulomonas Flavigena)为复合接种剂,对不同接种条件和控温条件下的联合堆肥中试进行了研究.实验结果表明,在一次发酵的初始阶段,以体积分数0.5%的接种量向堆肥中接种纤维素降解复合菌剂可有效提高发酵过程堆料中纤维素降解菌的种群密度,并使其迅速成为优势菌群,尤其是当堆体处于控温55℃的工况条件时,其菌群密度可保持在3.84×109~1.80×1010CFU/g;在二次发酵的初始阶段,以体积分数1%的接种量接种,可有效提高二次发酵阶段堆温的回升.对堆料中木质素和纤维素含量以及堆肥终产物的粒径分布指标--过筛率的检测表明,接种的复合纤维素降解菌可有效地降解堆料中的木质纤维素,接种处理中纤维素的降解率比不接种处理高23.64%,接种处理堆肥终产物的过筛率(2.0 cm)比不接种处理高18.28%.研究表明,用纤维素降解复合菌剂进行二次接种二次发酵,能够有效地促进蔬菜-花卉秸秆联合好氧堆肥中物料的纤维素组分的降解,达到加快堆肥进程,提高堆肥品质的目的. 相似文献
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尾矿坝地质生态环境风险防护措施分析 总被引:1,自引:0,他引:1
尾矿坝的环境风险主要是发生溃坝后对生态环境、水环境造成的不良影响。发生溃坝事故的根源是尾矿坝存在隐患,主要原因有先天因素和后天因素两种,先天因素主要有:尾矿坝建设前期工作中,对自然条件了解不够、尾矿坝设计不当、尾矿坝施工质量不良等;后天因素主要是在尾矿坝生产运行中,由不具备专业知识的人员管理,未按设计要求或有关规定执行。因此,预防溃坝的环境风险防护措施,要从防洪设计、增强坝体稳定性及加强管理等方面进行。 相似文献
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Rakocevic-Nedovic J Hollert H 《Environmental science and pollution research international》2005,12(3):146-152
Background, Aims and Scope Phytoplankton, as a first step in trophic cascades of lakes, can be a good indicator of trophic states, considering that every environmental change affects this community and many species of this community are sensitive to changes, and that they response very quickly. In this study, we tried to assess and predict the trophic state of Lake Skadar according to phytoplankton data.Methods Water samples were collected using Ruttner sampling bottle. Temperature, dissolved oxygen, ph, conductivity and transparence were measured in situ using portable equipment. Nutrients and chlorophyll a were measured using standard spectrophotometric methods. A determination of phytoplankton species was performed using relevant keys and the counting of cells was performed using sedimentation methods.Results and Discussion The species composition of Lake Skadar revealed 95 taxa, with Chlorophyceae and Bacillariophyceae being represented best. According to an average chlorophyll a concentration of 5.9 µg/l, Lake Skadar belongs to the mesotrophic level of the trophic scale. Developed prediction equation for chlorophyll a revealed a good prediction (R2=0.71) and the parameter Secchi depth was primarily correlated with chlorophyll a concentration. Trophic state indices derived from chlorophyll a and transparency, were close together, but both were below the phosphorous index. Values of trophic state indices rank the Lake Skadar as being mesotrophic. This study also showed that indices of diversity based on phytoplankton are weak indicators of trophic status and that they can well characterize only differences between assemblages and associations. According to calculated saprobic indices (ranging from 1.5 to 2.15), Lake Skadar is on betamesosaprobic level of saprobity, which means that it is moderately polluted with organic compounds. Conclusions Total phosphorus is not the main limiting factor for the phytoplankton community in Lake Skadar. Disagreements between chlorophyll and the transparency index, on the one hand, and the total phosphorus index, on the other, suggest that the phytoplankton in Lake Skadar is probably limited by other factors than phosphorus, such as nitrogen, toxic substances or intense zooplankton grazing. According to the majority of investigated parameters and indices derived from phytoplankton data, Lake Skadar is mesotrophic, with tendencies toward eutrophic levels during the summer period. Recommendations and Outlook Long-term monitoring is required for a better estimation of state and the conditions of Lake Skadar. Further studies on factors influencing the phytoplankton community, especially zooplankton grazing and toxic substances, which were not included in this study, should be continued in the future to improve the efficiency of phytoplankton usage in estimating the ecological and trophic conditions of Lake Skadar. 相似文献
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阿特拉津降解菌的生长规律及降解特征的实验 总被引:2,自引:0,他引:2
应用了从农药厂阿特拉津生产车间污泥中分离出的菌种AT菌,进行了菌种生长曲线的测定,求得AT菌的对数期代时为3.87d,生长速率为0.258d^-1;不同基质浓度的降解实验表明,在农药污染质阿特拉津的低浓度体系中,AT菌降解阿特拉津的反应符合一级动力学模式,属于米氏方程曲线的第一阶段的情形,并拟合出关系式V=0.064S。 相似文献
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主要对环境监测质量保证工作中出现的问题进行了阐述,并就如何有效开展环境监测质量保证工作提出了几点建议。 相似文献
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为了解决生命周期评价中普遍存在的环境负荷数据向环境成本转换问题,在清单分析的基础上,构建了产品生命周期环境成本评价模型。分析了评价模型对于生成评估报告和制定相关政策措施的作用和意义。 相似文献