应用生态学报2012，Vol.23Issue(4)：1083-1089,7.
模拟咸水入侵对崇明岛河岸带根际土壤微生物及反硝化作用的影响
Effects of saltwater incursion on the microbiological characteristics and denitrification in a riparian rhizosphere soil in Chongming Island of Shanghai, East China
摘要
Abstract
A simulation test was conducted to study the effects of saltwater incursion on the microbiological characteristics and denitrification in the riparian rhizosphere soils vegetated with different plants in Chongming Island of Shanghai. Saltwater incursion changed the microflora in the rhizos-pheric soils. Except for actinomycete whose quantity had slight increase, the quantities of bacteria, fungi, nitrifiers, and denitrifiers all decreased to some extent by saltwater incursion, with the deni-trifiers decreased by 51.8% , suggesting that the riparian soil microflora responded differentially to saltwater incursion. The activities of soil nitrogen-transforming enzymes were significantly inhibited by saltwater incursion, and the inhibitory effects differed with the enzymes. Nitrite reductase activity was most sensitive to saltwater incursion, with an inhibition rate of 43. 5% , followed by urease activity, with 37. 4% inhibition, and by dehydrogenase (29.5% inhibition). Saltwater incursion inhibited the denitrification, with the average denitrification rate decreased by 34. 9% . There existed significant differences in the eco-physiological responses of the microbes in the rhizosphere soils vegetated with different plants to the saltwater incursion. The microbial quantities and enzyme activities showed the highest inhibition percentages in the rhizosphere soil of Zizania aquatica, followed by in the rhizosphere soils of Acorus calamus and Phragmites australis. Under saltwater incursion, the inhibition percentages of microbial quantities, enzyme activities, and denitrification rate in the rhizosphere soil of A. calamus-P. australis were significantly lower, as compared with those in the rhizosphere soils vegetated with Z. aquatica, A. calamus, and P. australis, respectively, suggesting that mixed vegetation showed a better buffer effect on the responses of riparian rhizosphere soil microbiological processes and denitrification to saltwater incursion.关键词
河岸带湿地/咸水入侵/土壤微生物区系/氮转化酶/反硝化速率Key words
riparian wetland/ saltwater incursion/ soil microflora/ nitrogen-transforming enzyme/ denitrification rate分类
资源环境引用本文复制引用
杨长明,蔡雯娟,李建华..模拟咸水入侵对崇明岛河岸带根际土壤微生物及反硝化作用的影响[J].应用生态学报,2012,23(4):1083-1089,7.基金项目
污染控制与资源化研究国家重点实验室自主课题(PCRY09005)和国家科技支撑计划项目(2009BAC62B03)资助. （PCRY09005）
