This study investigates the testate amoeba communities of a large peatland in Central China. The ecology and seasonal variability of testate amoeba communities were studied during 2009-2010. Investiga- tion of environ...This study investigates the testate amoeba communities of a large peatland in Central China. The ecology and seasonal variability of testate amoeba communities were studied during 2009-2010. Investiga- tion of environmental controls using ordination showed that the relationship between testate amoeba communities and depth to water table （DWT） and pH are extremely weak. The small proportion of variance explained by water table depth here （only 1.9% in the full data） shows that the hydrological control is weaker than we expected in this peatland, and weaker than any study we are aware of using a similar methodology. Attempts to develop species- environment （transfer function） models or identify indi- cator species for future palaeoecological studies were unsuccessful. Previous large-scale studies of peatland testate amoeba ecology have been largely restricted to Europe and North America and results have been relatively consistent among studies. Our results contrast with this consensus and suggest that at least in minerotrophic peatlands in China testate amoeba communities may be primarily controlled by different environmental variables. In China, testate amoebae have been relatively little studied but may prove to be valuable for a variety of applications in palaeoecology and biomonitoring and much further work is required.展开更多
The middle Yangtze Reach is one of the most developed regions of China. As a result, most lakes in this area have suffered from eutrophication and serious environmental pollution during recent decades. The aquatic bio...The middle Yangtze Reach is one of the most developed regions of China. As a result, most lakes in this area have suffered from eutrophication and serious environmental pollution during recent decades. The aquatic biodiversity in the lakes of the area is thus currently under significant threat from continuous human activities. Testate amoebae （TA） are benthic （rarely planktonic） microorganisms characterized by an agglutinated or autogenous shell. Owing to their high abundance, preservation potential in lacustrine sediments, and distinct response to environmental stress, they are increasingly used as indicators for monitoring water quality and reconstructing palaeoenvironmental changes. However this approach has not yet been developed in China. This study presents an initial assessment of benthic TA assemblages in eight lakes of Lake Donghu in the region of Wuhan, China. Testate amoeba community structure was most strongly correlated to water pH. In more alkaline conditions, communities were dominated by Centropyxis aculeata, Difflugia oblonga, Pontigulasia compressa, Pon. elisa and Lesquereusia modesta. These results are consistent with previous studies and show that TA could be useful for reconstructing past water pH fluctuations in China. To achieve this, the next step will be to expand the database and build transfer function models.展开更多
基金Acknowledgements This work was supported by the National Basic Research Program of China （No. 2011CB808800）, the National Natural Science Foundation of China （Grant Nos. 40930210, 40921062, 40872202, 41072261 and 30800097）, the Opening Research Fund of Key Laboratory of Wetland Ecology and Environment （No. WELF-2009-B-003）, the Special Fund for Basic Scientific Research of Central Colleges, China University of Geosciences （Wuhan） （Nos. CUG090103 and G1323521132）, and the 111 Project （No. B08030）. Professor Robert K. Booth and Professor Edward A.D. Mitchell helped with species identifications, Professor Booth also helped withinitial statistical analysis and constructive comments on the research. We thank Jiantao Xue, Ze Zhang, Huan Yang and Zhiqi Zhang for their assistance of field works. Qianfan Zhang and Rong Zhu helped dealing with the processing of samples in the laboratory.
文摘This study investigates the testate amoeba communities of a large peatland in Central China. The ecology and seasonal variability of testate amoeba communities were studied during 2009-2010. Investiga- tion of environmental controls using ordination showed that the relationship between testate amoeba communities and depth to water table （DWT） and pH are extremely weak. The small proportion of variance explained by water table depth here （only 1.9% in the full data） shows that the hydrological control is weaker than we expected in this peatland, and weaker than any study we are aware of using a similar methodology. Attempts to develop species- environment （transfer function） models or identify indi- cator species for future palaeoecological studies were unsuccessful. Previous large-scale studies of peatland testate amoeba ecology have been largely restricted to Europe and North America and results have been relatively consistent among studies. Our results contrast with this consensus and suggest that at least in minerotrophic peatlands in China testate amoeba communities may be primarily controlled by different environmental variables. In China, testate amoebae have been relatively little studied but may prove to be valuable for a variety of applications in palaeoecology and biomonitoring and much further work is required.
基金This work was supported by the National Basic Research Program of China （No. 2011CB808800）, the National Natural Science Foundation of China （Grant Nos. 40930210, 40921062, 41072261 and 41130207）, the Special Fund for Basic Scientific Research of Central Colleges, China University of Geosciences （Wuhan_CUGL100502, G1323521132）, the 111 project （B08030） and the Opening Research Fund of State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment （SKLLQG1118）. Dr. Yangmin Qin thanks all the team of the Laboratory of Soil Biology at University of Neuchatel for inviting him visiting the laboratory and providing facilities and help.
文摘The middle Yangtze Reach is one of the most developed regions of China. As a result, most lakes in this area have suffered from eutrophication and serious environmental pollution during recent decades. The aquatic biodiversity in the lakes of the area is thus currently under significant threat from continuous human activities. Testate amoebae （TA） are benthic （rarely planktonic） microorganisms characterized by an agglutinated or autogenous shell. Owing to their high abundance, preservation potential in lacustrine sediments, and distinct response to environmental stress, they are increasingly used as indicators for monitoring water quality and reconstructing palaeoenvironmental changes. However this approach has not yet been developed in China. This study presents an initial assessment of benthic TA assemblages in eight lakes of Lake Donghu in the region of Wuhan, China. Testate amoeba community structure was most strongly correlated to water pH. In more alkaline conditions, communities were dominated by Centropyxis aculeata, Difflugia oblonga, Pontigulasia compressa, Pon. elisa and Lesquereusia modesta. These results are consistent with previous studies and show that TA could be useful for reconstructing past water pH fluctuations in China. To achieve this, the next step will be to expand the database and build transfer function models.
