1 Introduction The vertical stratification of the water column has a significant impact on the spatial distribution of aquatic organisms,the dynamics and structure of the food web in
Cladocera are filter feeders abundant in freshwaters,which consume phytoplankton particles in wide size and taxonomic ranges.The ability of cladocerans to control phytoplankton abundance by grazing is determined by va...Cladocera are filter feeders abundant in freshwaters,which consume phytoplankton particles in wide size and taxonomic ranges.The ability of cladocerans to control phytoplankton abundance by grazing is determined by various factors including the characteristics of phytoplankton.Freshwater salinization may reduce the strength of top-down grazing control of phytoplankton because of the detrimental effects of salinity on the grazing intensity of zooplankters.We performed grazing experiments with two species of Cladocera of different body lengths to test their ability to graze on phytoplankton in natural waters differing in salinity and size and taxonomic composition of food particles.Grazing experiments demonstrated that the grazing rate was mostly controlled by the abundance of phytoplankton in the medium.The grazing rate was reduced at salinity ca.above 3 g/L of NaCl in the medium.The lower grazing rate was observed in the medium with larger phytoplankton particles.Both species predominantly consumed phytoplankton particles with a diameter of 6-12μm,which may shift the size distribution of phytoplankton towards a larger average diameter of particles.The taxon-specific feeding was also observed,as both species predominantly consumed diatom algae.Thus,we found that because of grazing,the size and taxonomic characteristics of phytoplankton are shifted towards a less edible community.The detrimental effect of elevated salinity on grazing rate supports growing concern about freshwater salinization negatively affecting water quality,particularly reducing top-down grazing control of phytoplankton.展开更多
Saline lakes are widespread on all continents.Since 1979,an informal international association of salt lake researchers from a variety of disciplines has sponsored a series of triennial conferences to foster scientifi...Saline lakes are widespread on all continents.Since 1979,an informal international association of salt lake researchers from a variety of disciplines has sponsored a series of triennial conferences to foster scientific exchange and our understanding of saline lakes.International Society for Salt Lake Research(ISSLR,www.isslr.org)was founded in 1994 to establish effective liaison between persons interested in any aspect of inland saline waters,to encourage these interests,and to educate the public in the scientific use,management,and conservation of salt lakes.ISSLR conferences are held triennially.The conferences are usually hosted by a local University or research institution and provide an excellent opportunity for networking among globally dispe rsed researchers.展开更多
基金supported by the Integration Project of SB RAS No. 56Russian Foundation for Basic Research grant No. 13-05-00853
文摘1 Introduction The vertical stratification of the water column has a significant impact on the spatial distribution of aquatic organisms,the dynamics and structure of the food web in
基金supported by the State Assignment of the Ministry of Science and Higher Education of the RF(No.0287-2021-0019).
文摘Cladocera are filter feeders abundant in freshwaters,which consume phytoplankton particles in wide size and taxonomic ranges.The ability of cladocerans to control phytoplankton abundance by grazing is determined by various factors including the characteristics of phytoplankton.Freshwater salinization may reduce the strength of top-down grazing control of phytoplankton because of the detrimental effects of salinity on the grazing intensity of zooplankters.We performed grazing experiments with two species of Cladocera of different body lengths to test their ability to graze on phytoplankton in natural waters differing in salinity and size and taxonomic composition of food particles.Grazing experiments demonstrated that the grazing rate was mostly controlled by the abundance of phytoplankton in the medium.The grazing rate was reduced at salinity ca.above 3 g/L of NaCl in the medium.The lower grazing rate was observed in the medium with larger phytoplankton particles.Both species predominantly consumed phytoplankton particles with a diameter of 6-12μm,which may shift the size distribution of phytoplankton towards a larger average diameter of particles.The taxon-specific feeding was also observed,as both species predominantly consumed diatom algae.Thus,we found that because of grazing,the size and taxonomic characteristics of phytoplankton are shifted towards a less edible community.The detrimental effect of elevated salinity on grazing rate supports growing concern about freshwater salinization negatively affecting water quality,particularly reducing top-down grazing control of phytoplankton.
基金supported by the State Assignment of the Ministry of Science and Higher Education of the Russian Federation(No.0287-2021-0019)。
文摘Saline lakes are widespread on all continents.Since 1979,an informal international association of salt lake researchers from a variety of disciplines has sponsored a series of triennial conferences to foster scientific exchange and our understanding of saline lakes.International Society for Salt Lake Research(ISSLR,www.isslr.org)was founded in 1994 to establish effective liaison between persons interested in any aspect of inland saline waters,to encourage these interests,and to educate the public in the scientific use,management,and conservation of salt lakes.ISSLR conferences are held triennially.The conferences are usually hosted by a local University or research institution and provide an excellent opportunity for networking among globally dispe rsed researchers.
