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471.
472.
垃圾填埋场空气真菌群落结构和时空分布特征 总被引:2,自引:1,他引:1
为了解垃圾填埋场空气真菌的群落结构和浓度、粒径的时空分布,在北京市某垃圾卫生填埋场填埋区、渗滤液处理区、生活区分别选定监测点,利用安德森六级微生物采样器,对填埋场空气真菌进行了系统的定点取样和分析.结果表明,除无孢菌外,共出现了15属空气真菌.优势菌属依次为枝孢属(Cladosporium)、曲霉属(Aspergillus)、青霉属(Penicillium)、无孢菌群(Non-sporing).填埋区和渗滤液处理区空气真菌浓度约为1 750 CFU.m-3,明显高于生活区(p0.05).2006年4月~2007年1月空气真菌浓度变化曲线呈双峰型,2个高峰分别出现在5月和9~10月,浓度可达5 000 CFU.m-3以上.填埋区4~7月空气真菌09:00~11:00的浓度低于15:00~16:00,在8月~次年1月趋势相反.空气真菌粒子在Ⅲ~Ⅴ级约占总数的75%.填埋区和渗滤液处理区的空气真菌中值直径均为2.9μm,生活区为2.8μm,3个功能区空气真菌的中值直径没有差异(p0.05). 相似文献
473.
大量的非离子表面活性剂应用于工业生产和人类日常生活,在洗涤污垢的同时这类表面活性剂也排入环境造成污染,吐温-80是其中之一。文章从生活污水污染的土壤中分离纯化一株高效降解吐温-80的真菌菌株,其与尖孢镰刀菌(Fusarium oxysporum)亲缘关系最近。该菌株降解吐温-80的最适温度30℃,pH为6.0。吐温-80浓度高于8000mg/L条件下此菌株仍然旺盛生长,但装液量大于80mL(100mL瓶),小于40mL(100mL瓶)以及转速小于50r/min,大于130r/min时生长迟缓。 相似文献
474.
Methamidophos was widely used a pesticide in northern China. The potential influences of methamidophos on soil fungal community in black soil were assessed by plate count, 28S rDNA-PCR-DGGE, and clone library analysis. Three methamidophos levels (50, 150, and 250 mg/kg) were tested in soil microcosms. Results from plate count during a 60-d microcosm experiment showed that high concentrations of methamidophos (250 mg/kg) could significantly stimulate fungal populations. DCGE (denaturing gradient gel electrophoresis) fingerprinting patterns showed a significant difference between the responses of culturable and total fungi communities under the stress of methamidophos. Shannon diversity indices calculated from DGGE profiles indicated that culturable fungi in all microcosms with methamidophos treatment increased after 1 week of incubation. However, the diversity indices of total fungi decreased in the first week, as compared to the stimulation of culturable fungi. At the 8th week, however, all the microcosms treated by methamidophos were similar to the control microcosms in community structure as suggested by the Shannon diversity indices for both culturable and total fungi. In contrast, after 1 week the fungal structure of culturable and unculturable both were disturbed to different extent under the stresses of methamidophos by clustering analysis. Clone sequencing analysis indicated the stimulation of pathogenic and unculturable fungal populations by methamidophos treatment, suggetsing potential risks of plant disease outbreak. 相似文献
475.
Two different functional biofilters were carried out and compared for the treatment of off-gas containing multicomponent odors and volatile organic compounds (VOCs) in this study. The effects of pH values and the empty bed retention time (EBRT) on the performance of the bioreactors were studied; and the characteristics of microbial populations in the two biofilters were also determined. The experimental results indicated that the removal effciencies of hydrophilic compounds such as butyric acid and ammonia ... 相似文献
476.
Aqueous extracts from various plant parts of fenugreek (3%) (aerial parts: leaves and stems (LS), roots (R), ground seeds (GS) and
not ground seeds (NGS)) and petroleum ether, ethyl acetate and methanolic fractions of the aerial parts were assayed to determine
their antifungal potential against Botrytis cinerea, Fusarium graminearum, Alternaria sp., Pythium aphanidermatum, and Rhizoctinia
solani. All fenugreek plant parts showed antifungal potential and the magnitude of their inhibitory e ects was species and plant parts
dependent. R extract was shown less toxic (30.38%), whereas NGS extract expressed the strongest inhibition, with an average of
71.44%, followed by GS (58.56%) and LS (57.1%). Screening indicated that P. aphanidermatum was the most resistant species, with an
average inhibition of 34.5%. F. graminearum, Alternaria sp. and R. solani were the most sensitive species, and were similarly inhibited
(63.5%). The stability test indicated that the aqueous extracts of all plant parts lost approximately 50% of their relative activity after one
month of storage at 4°C, whilst they lost 60%–90% of their activity when stored at ambient temperature for one month. The antifungal
activity resided mainly in the methanol fraction and the minimum inhibitory concentration (MIC) of methanol fraction witch caused
total inhibition of R. solani and Alternaria sp. was 60 g/ml. Results of current study suggested that the constituents of Trigonella
foenum-graecum have potential against harmful pathogenic fungi. Therefore, fenugreek could be an important source of biologically
active compounds useful for developing better new antifungal drugs. 相似文献
477.
Integrating Joint Implementation Projects for Energy Efficiency on the Built Environment with White Certificates in The Netherlands 总被引:2,自引:1,他引:1
V. Oikonomou W. van der Gaast 《Mitigation and Adaptation Strategies for Global Change》2008,13(1):61-85
In this paper we analyze policy interactions between two innovative climate and energy policy instruments, namely White Certificates
(WhC) and Joint Implementation (JI) that target at energy efficiency improvement and reductions of Greenhouse Gas (GHG) emissions.
We have selected The Netherlands and Bulgaria as a case study given that the former has a cumulated experience in energy efficiency
policies and the latter for a growing potential in JI projects as a host country. Based on a method of analyzing policy interactions,
we demonstrate how a possible design of such a scheme can take place and how it should function. A couple of parameters that
deserve attention are a baseline definition and a conversion rate for credits. Our basic finding is that an integrated scheme
is complementary and can assist substantially in achieving Dutch national United Nations Framework Convention on Climate Change
(UNFCCC) Kyoto Protocol targets. Dutch electricity and gas suppliers (parties that receive energy efficiency obligations)
can implement energy efficiency projects domestically and in other countries, hence reducing total abatement costs. Furthermore,
such a scheme can stimulate further energy efficiency actions from other stakeholders participating in energy markets. Based
on an ex-ante assessment, a carefully designed hybrid WhC and JI scheme appears to be effective in terms of targets, efficient,
generating positive impacts on markets and society, while uncertain in stimulating innovation.
相似文献
V. OikonomouEmail: |
478.
无公害食用菌生产技术规程的制定研究 总被引:1,自引:0,他引:1
通过分析近年来我国食用菌生产管理和产品质量安全存在的问题,论述了开展无公害食用菌生产的重要性.同时吸收各地的生产经验.根据国家有关标准,从食用菌生产场所的选择、培养基材料和水的要求、栽培管理、病虫害防治、采后处理、加工贮藏和产品质量安全检测等几个方面,提出了一整套较系统的无公害食用菌生产技术操作规程.该项技术规程在生产上的推广应用,对提高食用菌生产技术水平、改善和保障食用菌产品质量、增强产品在国际市场的竞争力将产生积极的推动作用. 相似文献
479.
Cadaver decomposition in terrestrial ecosystems 总被引:3,自引:0,他引:3
A dead mammal (i.e. cadaver) is a high quality resource (narrow carbon:nitrogen ratio, high water content) that releases an
intense, localised pulse of carbon and nutrients into the soil upon decomposition. Despite the fact that as much as 5,000 kg
of cadaver can be introduced to a square kilometre of terrestrial ecosystem each year, cadaver decomposition remains a neglected
microsere. Here we review the processes associated with the introduction of cadaver-derived carbon and nutrients into soil
from forensic and ecological settings to show that cadaver decomposition can have a greater, albeit localised, effect on belowground
ecology than plant and faecal resources. Cadaveric materials are rapidly introduced to belowground floral and faunal communities,
which results in the formation of a highly concentrated island of fertility, or cadaver decomposition island (CDI). CDIs are
associated with increased soil microbial biomass, microbial activity (C mineralisation) and nematode abundance. Each CDI is
an ephemeral natural disturbance that, in addition to releasing energy and nutrients to the wider ecosystem, acts as a hub
by receiving these materials in the form of dead insects, exuvia and puparia, faecal matter (from scavengers, grazers and
predators) and feathers (from avian scavengers and predators). As such, CDIs contribute to landscape heterogeneity. Furthermore,
CDIs are a specialised habitat for a number of flies, beetles and pioneer vegetation, which enhances biodiversity in terrestrial
ecosystems. 相似文献
480.
研究了2株多氯代二苯并二噁英高效降解白腐菌Phlebia lindtneri及Phlebia brevispora对氯丹的降解能力.在2个不同的液体培养体系中,2菌株对于高浓度(25μmol/L)的反式氯丹展现了较高的代谢能力,经6周培养后其降解率均达到50%以上.用GC/MS对其降解产物分析表明,氯丹的降解存在脱氢,脱氯化氢,羟基化以及氯原子的羟基置换4条不同的初始降解途径,除七氯,环氧七氯及氧化氯丹等常见初始代谢产物外,还发现3-羟基氯丹,氯代六氯醇,七氯二醇,羟基六氯,二羟基六氯等大量的羟基化代谢产物.尤其是P. lindtneri可以将曾被认为是终端代谢产物的氧化氯丹进行降解,并通过氯原子的羟基置换作用将其转化成羟基化代谢产物. 相似文献