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Olesya V. Anishchenko Michail I. Gladyshev Elena S. Kravchuk Elena A. Ivanova Iliada V. Gribovskaya Nadezhda N. Sushchik 《Central European Journal of Biology》2010,5(1):125-134
The concentrations of metals K, Na, Ca, Mg, Fe, Mn, Zn, Cu, Ni, Pb, Co and Cr, in the water and periphyton (epilithic algal
communities) were studied at a site in the middle stream of the Yenisei River (Siberia, Russia) during three years using monthly
sampling frequencies. Despite considerable seasonal variations in aquatic concentrations of some metals, there was no correlation
between metal contents in the water and in periphyton. Seasonal concentration variations of some metals in periphyton were
related to the species (taxonomic) composition of periphytic microalgae and cyanobacteria. Enhanced levels of Ni and Co in
periphyton in late autumn, winter, and early spring were likely caused by the predominance of cyanobacteria in the periphytic
community, and annual maximum levels of K in periphyton in late spring and early summer were attributed to the domination
of Chlorophyta, primarily Ulothrix zonata. 相似文献
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A. P. Tolomeev O. V. Anishchenko E. S. Kravchuk O. V. Kolmakova L. A. Glushchenko O. N. Makhutova A. A. Kolmakova V. I. Kolmakov M. Yu. Trusova N. N. Sushchik M. I. Gladyshev 《Contemporary Problems of Ecology》2014,7(4):489-500
An integrated study of the middle and lower Yenisei River was performed in the summer of 2012. It involved monitoring the key elements and ecological processes associated with the carbon cycle of the river ecosystem (the study area is more than 1800 km long). Measurements of the production and destruction processes have shown the failure of the “neutral pipe” hypothesis claiming that any river is a simple drain of carbon from terrestrial ecosystems to the ocean. The Yenisei River is not a purely heterotrophic ecosystem. It also has autotrophic areas, where the primary production of planktonic photosynthesis is higher than respiration (above the Angara River and near the Bolshaya and Malaya Heta rivers). According to the data, the respiration rate of the plankton community in the river depends mostly on the water temperature and the content of inorganic phosphorous that can restrict the amount of organic matter consumed by bacterioplankton. 相似文献
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Seasonal dynamics of Anabaena flos-aquae (Lyngb.) Breb., including vegetative cells, akinetes and akinete envelopes, in bottom sediments and water column at both littoral and deeper central stations of a small Siberian reservoir was studied. Two types of akinetes were observed: in the first half of summer Anabaena formed akinetes, which served for vegetative reproduction and germinated in water column soon after differentiation, while in the second half of summer the akinetes produced served as a resting stages, which were deposited to bottom sediments. Canonical correlation analyses revealed that decrease of water temperature was the main environmental factor that stimulated the akinete formation. In contrast to the general opinion, concentration of inorganic phosphorus slightly, but positively influenced the akinete formation. Thus, akinetes formed in response to the temperature decrease, needs a certain level of this nutrient. At littoral and open-water stations abundance and seasonal dynamics of akinetes in water column and their sinking pattern were very similar. However, seasonal dynamics of abundance of akinetes in sediments in these two reservoir locations differed: whereas the abundance of akinetes in open water increased permanently during the summer, that in the littoral decreased soon after their sedimentation. The cause for decrease in abundance of akinetes in bottom sediments in winter is unknown. 相似文献
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