提取南极阿德雷岛沉积物柱状样各层次的总DNA,利用PCR-RFLP方法,对沉积物中的细菌多样性及分布进行了研究,并探讨了它与环境的关系.结果表明,沉积物中的细菌多样性丰富,分属于8个类群,以CFB(Cytophaga-Flexibacter-Bacterioides)类群和P...提取南极阿德雷岛沉积物柱状样各层次的总DNA,利用PCR-RFLP方法,对沉积物中的细菌多样性及分布进行了研究,并探讨了它与环境的关系.结果表明,沉积物中的细菌多样性丰富,分属于8个类群,以CFB(Cytophaga-Flexibacter-Bacterioides)类群和Proteobacteria类群的β-,γ-亚群为主.在7 cm左右深度的沉积物中,可培养微生物和16 S rDNA序列多样性与其他深度的沉积物有明显不同,推测与环境的变化有关.同时还发现了大量与降解有机化合物相关的细菌,表明阿德雷岛的微生物生态系统已经受到了人类活动的影响.展开更多
Two short sediment cores named ZS and THS dated by the 210Pb or 137Cs method were collected from the northwest and southwest of Taihu Lake respectivly,and total organic carbon(TOC) and nutrients including total nitrog...Two short sediment cores named ZS and THS dated by the 210Pb or 137Cs method were collected from the northwest and southwest of Taihu Lake respectivly,and total organic carbon(TOC) and nutrients including total nitrogen(TN) and total phosphorus(TP) were determined to analyze the chronology and nutrients change in recent sediment.The results show that 137Cs activities are low(less than 15 Bq/kg) in the two cores,attributed to the 137Cs migration.Based on 210Pb constant rate of supply(CRS) model,the sedimentation accumulation rates range from 0.13 g/(cm2·yr) to 0.76 g/(cm2·yr) in the ZS core,and from 0.10 g/(cm2·yr) to 0.56 g/(cm2·yr) in the THS core.A remarkable increase in organic matter and nutrients has occurred in the two dated cores since the mid-1980s.The historical changes of organic matter and nutrients in the two cores are consisitent with the monitoring data for surface sediment after the 1960s.The TP accumulation rates after the early 1980s are 0.97 and 0.92 times higher than those from the 1950s to the 1980s in ZS and THS cores,respectively.Higher TP concentrations in the past two-decade deposits of Taihu Lake are due to both diagenetic factors and human activities.展开更多
文摘提取南极阿德雷岛沉积物柱状样各层次的总DNA,利用PCR-RFLP方法,对沉积物中的细菌多样性及分布进行了研究,并探讨了它与环境的关系.结果表明,沉积物中的细菌多样性丰富,分属于8个类群,以CFB(Cytophaga-Flexibacter-Bacterioides)类群和Proteobacteria类群的β-,γ-亚群为主.在7 cm左右深度的沉积物中,可培养微生物和16 S rDNA序列多样性与其他深度的沉积物有明显不同,推测与环境的变化有关.同时还发现了大量与降解有机化合物相关的细菌,表明阿德雷岛的微生物生态系统已经受到了人类活动的影响.
基金Under the auspices of National Key Science and Technology Special Program of Water Pollution Control and Treatment (No. 2008ZX07101-012-01)National Natural Science Foundation of China (No. 40902048, 40771197)Jiangsu Natural Sci-ence Foundation (No. BK2009331, BE2008690)
文摘Two short sediment cores named ZS and THS dated by the 210Pb or 137Cs method were collected from the northwest and southwest of Taihu Lake respectivly,and total organic carbon(TOC) and nutrients including total nitrogen(TN) and total phosphorus(TP) were determined to analyze the chronology and nutrients change in recent sediment.The results show that 137Cs activities are low(less than 15 Bq/kg) in the two cores,attributed to the 137Cs migration.Based on 210Pb constant rate of supply(CRS) model,the sedimentation accumulation rates range from 0.13 g/(cm2·yr) to 0.76 g/(cm2·yr) in the ZS core,and from 0.10 g/(cm2·yr) to 0.56 g/(cm2·yr) in the THS core.A remarkable increase in organic matter and nutrients has occurred in the two dated cores since the mid-1980s.The historical changes of organic matter and nutrients in the two cores are consisitent with the monitoring data for surface sediment after the 1960s.The TP accumulation rates after the early 1980s are 0.97 and 0.92 times higher than those from the 1950s to the 1980s in ZS and THS cores,respectively.Higher TP concentrations in the past two-decade deposits of Taihu Lake are due to both diagenetic factors and human activities.
