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351.
好氧堆肥高温期的嗜热真菌和嗜热放线菌群落结构 总被引:7,自引:0,他引:7
使用传统的培养方法和PCR-DGGE技术对好氧堆肥高温期的嗜热真菌和嗜热放线菌群落结构进行了研究.分别采用园林垃圾和餐厨垃圾作为堆肥原料,进行了20d好氧堆肥.高温期(≥50℃)持续了10d和8d.分别对2堆体高温期样品进行稀释平板混菌培养,真菌总数和放线菌总数均分别呈"降低-升高"和"升高-降低-升高"的趋势.同时提取微生物总DNA.分别使用真菌引物对(GC-NS7/NS8)和放线菌引物对(F243/GC-R513)从总DNA中成功扩增得到目标产物,对目标产物进行DGGE分离.传统培养法和DGGE图谱结果显示,不同堆体高温期的嗜热真菌和嗜热放线菌均表现出相似的变化规律,嗜热真菌优势菌比嗜热放线菌明显,但菌群总数比嗜热放线菌少.聚类分析结果表明,堆肥高温期嗜热真菌和嗜热放线菌分别以升温时56℃和58℃为界,分成2个明显的变化阶段,每阶段内部聚类关系较近.阶段间关系较远.温度对高温期真菌和放线菌具有明显的筛选作用. 相似文献
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分析了燃油加热炉烟尘的特点,研究并论述了燃油加热炉烟气清洁装置应采取的技术措施、性能特点及结构原理等。依据该研究设计的燃油加热炉清洁装置已在输油管道加热炉上应用并已取得了显著效果。 相似文献
354.
Yuhong SU Xueyun YANG Cary T CHIOU 《Frontiers of Environmental Science & Engineering in China》2008,2(4):468-474
To access the influence of a vegetation on soil microorganisms toward organic pollutant biogegration, this study examined
the rhizospheric effects of four plant species (sudan grass, white clover, alfalfa, and fescue) on the soil microbial community
and in-situ pyrene (PYR) biodegradation. The results indicated that the spiked PYR levels in soils decreased substantially compared to
the control soil without planting. With equal planted densities, the efficiencies of PYR degradation in rhizosphere with sudan
grass, white clover, alfalfa and fescue were 34.0%, 28.4%, 27.7%, and 9.9%, respectively. However, on the basis of equal root
biomass the efficiencies were in order of white clover >> alfalfa > sudan > fescue. The increased PYR biodegradation was attributed
to the enhanced bacterial population and activity induced by plant roots in the rhizosphere. Soil microbial species and biomasses
were elucidated in terms of microbial phospholipid ester-linked fatty acid (PLFA) biomarkers. The principal component analysis
(PCA) revealed significant changes in PLFA pattern in planted and non-planted soils spiked with PYR. Total PLFAs in planted
soils were all higher than those in non-planted soils. PLFA assemblages indicated that bacteria were the primary PYR degrading
microorganisms, and that Gram-positive bacteria exhibited higher tolerance to PYR than Gram-negative bacteria did. 相似文献
355.
Jinsong GUO Guohong YANG Fang FANG Yu QIN 《Frontiers of Environmental Science & Engineering in China》2008,2(4):439-445
In this study, three sequential batch biofilm reactors (SBBRs) were operated for 155 days to evaluate the performance of completely
autotrophic nitrogen removal over nitrite (CANON) process under different aeration modes and dissolved oxygen (DO). Synthetic
wastewater with 160-mg NH4
+-N/L was fed into the reactors. In the continuously-aerated reactor, the efficiency of the ammonium nitrogen conversion and
total nitrogen (TN) removal reached 80% and 70%, respectively, with DO between 0.8–1.0 mg/L. Whereas in the intermittently-aerated
reactor, at the aeration/non-aeration ratio of 1.0, ammonium was always under the detection limit and 86% of TN was removed
with DO between 2.0–2.5 mg/L during the aeration time. Results show that CANON could be achieved in both continuous and intermittent
aeration pattern. However, to achieve the same nitrogen removal efficiency, the DO needed in the intermittently-aerated sequential
batch biofilm reactor (SBBR) during the aeration period was higher than that in the continuously-aerated SBBR. In addition,
the DO in the CANON system should be adjusted to the aeration mode, and low DO was not a prerequisite to CANON process. 相似文献
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358.
根据1:10000条带状地质填图所获资料,分析了育王山山前断层的几何结构和新活动时代.断层北起岙张水库大坝东北,向南经河头蕉-竺家-陈家-钱家-俞家-王家一线以西,止于詹家西南,由2条次级段呈羽列式展布,北段为岙张水库-红岩水库段,南段为红岩水库东南-詹家段.剖面上断层地貌显示清楚,西侧为侏罗系构成的育王山低山,东侧为大楔盆地.各条断层皆由多个断面构成宽几米~几十米的断层带.根据探槽、天然剖面特征和OSL、ESR样品年龄测试结果综合分析,断层至少有两期活动,早期活动性质为逆断层,时间为早更新世,晚期活动性质为右旋走滑兼正断或逆断层,时间为中更新世,最新活动时代为中更新世晚期.通过探槽揭露,确定育王山山前洪积扇陡坎是人类活动造成,而非断层陡坎. 相似文献
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360.
海水养殖对生物多样性的影响研究进展 总被引:1,自引:1,他引:1
近年来,海水养殖对全球海水产品供应的贡献持续增加,但是海水养殖对海洋和沿海生物多样性以及海洋资源可持续利用产生的不利影响,已经引起国内外海洋、环境等领域科学家和大众的广泛关注.海水养殖对生物多样性的影响一般包括在海岸带地区建设养殖场对海域或土地生物多样性的影响,对为维持养殖生产活动所需的超量海域的生物多样性的影响,海水养殖残饵、代谢物污染及养殖生物外逃对海洋生态系生物多样性的影响等方面.本文首先综述了上述影响,并展望了我国海水养殖业生物多样性保护的管理对策,以期为海水养殖业可持续发展、海洋资源可持续利用和生物多样性保护提供参考. 相似文献