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Changes in soil microbial community structure associated with two types of genetically engineered plants analyzing by PLFA 总被引:3,自引:0,他引:3
With the rapid expansion of GEPs(genetically engineered plants), people are more and more concerned about the ecological risks brought by their release. Assessing the effect of GEPs on soil microbial ecology is indispensable to study their ecological risks. In our study, the phospholipids fatty acid(PLFA) method was used to analyze the microbial community of soil samples collected from fields with two types of GEPs-Bt transgenic com and PVY( potato virus Y) cell protein gene transgenic potato. The principal components analysis(PCA) showed all controls were on the right of related GEPs samples along the PC1 (the first principal component) axis, which means a decrease of fungi in soils with genetically engineered crop since most of PLFAs that are strongly positively correlated with PC1 represent fungi. For samples collected from Bt transgenic cornfield, the ratios of gram-positive to gram-negative bacteria were less than those of controls. For samples of transgenic potato field, these ratios were lower than those of controls when soils were collected from deep layer(20-40 cm), but were higher when soils collected from surface layer(0-20 cm). For soils collected from 0-20 cm, the ratios of fungi to bacteria for all GEPs samples were at the same level. So were such rations for all controls. Changes of soil microbial community in two types of GEPs fields were detected in our study, but the causes and more information still needs further study. 相似文献
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CHI Yong WEN Jun-ming ZHANG Dong-ping YAN Jian-hu NI Ming-jiang CEN Ke-fa 《环境科学学报(英文版)》2005,17(4):699-704
IntroductionWiththedepletionofspaceforlandfillingofmunicipalsolidwasteandtherisingpricesforrawmaterials ,moreandmorefluidizedbedincineratorshavebeenusedtotreatMSWduetotheprimaryadvantagesofhygieniccontrol,volumereductionandenergyrecovery .BecausetheMSWhas… 相似文献
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2002年,在乌鲁木齐市5个采样点分别采集了环境空气中的总悬浮颗粒物(TSP)和可吸入颗粒物(PM10).用化学质量平衡 (CMB)受体模型和二重源解析技术解析了TSP和PM10的来源,结果表明,各主要源类对TSP的分担率依次为扬尘34%、燃煤尘26%、建筑水泥尘10%、硫酸盐8%、土壤风沙尘7%、机动车尾气尘6%、钢铁尘2%、硝酸盐1%、其它6%;对PM10的分担率依次为扬尘30%、燃煤尘28%、建筑水泥尘11%、硫酸盐10%、机动车尾气尘8%、土壤风沙尘8%、硝酸盐1%、其它3%. 相似文献
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