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61.
Effects of plant species coexistence on soil enzyme activities and soil microbial
community structure under Cd and Pb combined pollution 总被引:6,自引:1,他引:5
The relationship between plant species coexistence and soil microbial communities under heavy metal pollution has attracted much
attention in ecology. However, whether plant species coexistence could o set the impacts of heavy metal combined pollution on soil
microbial community structure and soil enzymes activities is not well studied. The modified ecological dose model and PCR-RAPD
method were used to assess the e ects of two plant species coexistence on soil microbial community and enzymes activities subjected
to Cd and Pb combined stress. The results indicated that monoculture and mixed culture would increased microbe populations under
Cd and Pb combined stress, and the order of sensitivity of microbial community responding to heavy metal stress was: actinomycetes
> bacteria > fungi. The respirations were significantly higher in planted soil than that in unplanted soil. The plant species coexistence
could enhance soil enzyme activities under Cd and Pb combined. Furthermore, planted soil would be helpful to enhance soil genetic
polymorphisms, but Cd and Pb pollution would cause a decrease on soil genetic polymorphisms. Mixed culture would increase
the ecological dose 50% (ED50) values, and the ED50 values for soil enzyme activities decreased with increasing culture time. The
dehydrogenase was most sensitive to metal addition and easily loses activity under low dose of heavy metal. However, it was di cult
to fully inhibit the phoshpatase activity, and urease responded similarly with phosphatase. 相似文献
62.
63.
Lichens are widely used in biomonitoring studies of air pollution, either as bioindicators of air quality or as bioaccumulators
of atmospheric deposition. Over the past decade, several molecular techniques have been developed to provide information on
diversity, genotoxicology, genetic relationships, etc. The heavy metal contents of Evernia prunastri samples were determined by
atomic absorption spectrometry. The Random Amplified Polymorphic DNA Polymerase Chain Reaction (RAPD-PCR) method was
used to describe the pattern of DNA band variation in the samples influenced by the environmental pollution. The study was designed
to describe the level of pollution in an area contaminated with smoke and waste from an iron-steel factory, and to reveal the level
of potential genotoxic agents around this source of pollution. The study also examined the suitability of the lichen samples for the
detection of genotoxicity. 相似文献
64.
低浓度溴氰菊酯连续暴露对罗非鱼DNA的影响 总被引:6,自引:0,他引:6
运用RAPD技术和外周血嗜多染红细胞微核试验来分析和评价低浓度溴氰菊酯连续暴露对罗非鱼DNA的影响.RAPD试验结果表明,在12个能扩增出罗非鱼基因组DNA的引物中,引物S326能检测出3 μg/L以上浓度溴氰菊酯暴露前后罗非鱼基因组DNA的差异,而小于2.0 μg/L的低浓度溴氰菊酯对罗非鱼基因组DNA没有影响.外周血嗜多染红细胞微核试验结果表明,在一定浓度的溴氰菊酯连续暴露后,2.0 μg/L以下浓度组罗非鱼外周血红细胞微核率与对照组相比没有显著差异(P>0.05),而3 μg/L以上浓度组可诱导罗非鱼外周血红细胞产生微核.微核率与对照组相比差异显著(P<0.05),且表现出明显的剂量-效应和时间-效应关系.研究表明,溴氰菊酯在一定条件下可对鱼类DNA产生影响. 相似文献