[1] The role of aquatic ecosystems in regional and global carbon cycles is becoming increasingly apparent, and lakes and reservoirs may be particularly important to the retention and processing of organic carbon. If this is the case, then lakes and reservoirs may act as control points that decrease OC concentrations and fluxes in downstream aquatic ecosystems. We tested this hypothesis at a reg...

We analyzed the genetic diversity (V4 region of the 18S rRNA) of planktonic microbial eukaryotes in four high mountain lakes including two remote biogeographic regions (the Himalayan mountains and the European Alps) and distinct habitat types (clear and glacier-fed turbid lakes). The recorded high genetic diversity in these lakes was far beyond of what is described from high mountain lake plank...

The acI lineage of freshwater Actinobacteria is a cosmopolitan and often numerically dominant member of lake bacterial communities. We conducted a survey of acI 16S rRNA genes and 16S-23S rRNA internal transcribed spacer regions from 18 Wisconsin lakes and used standard nonphylogenetic and phylogenetic statistical approaches to investigate the factors that determine acI community composition at...

The four large Swedish lakes Vänern, Vättern, Mälaren and Hjälmaren differ in many respects, not least in drainage area characteristics and basin morphometry (1). The differences also include water quality. Since nutrient chemistry of phosphorus (P) and nitrogen (N) in the lakes is of major concern, it has been treated by several authors (2–13). The hydrochemical studies started in 1964 and in ...

We investigated the effect of dissolved organic carbon (DOC) on hypolimnetic metabolism (accumulation of dissolved inorganic carbon (DIC) and methane (CH4)) in 21 lakes across a gradient of DOC concentrations (308 to 1540 !mol C L). The highly colored nature of the DOC in these lakes suggests it is mostly of terrestrial origin. Hypolimnetic methane accumulation was positively correlated with ep...

Forestry activities in the Canadian Boreal region have increased in the last decades, raising concerns about their potential impact on aquatic ecosystems. Water quality and fluorescence characteristics of dissolved organic matter (DOM) were measured over a 3-year period in eight eastern Boreal Shield lakes: four lakes were studied before, 1 and 2 years after forest harvesting (perturbed lakes) ...

Index words: Hemimysis Invasive species Great Lakes Ecological impact Food webs Risk assessment The bloody redmysid shrimp Hemimysis anomala is the most recent Ponto-Caspian invader of the Great Lakes. At present, there is a paucity of data that can be used to forecast its ecological impacts in North America; however, published studies of other invasive freshwater mysids (i.e. Mysis diluviana i...

BACKGROUND The Northern Great Plains of Canada are home to numerous permanent and ephemeral athalassohaline lakes. These lakes display a wide range of ion compositions, salinities, stratification patterns, and ecosystems. Many of these lakes are ecologically and economically significant to the Great Plains Region. A survey of the physical characteristics and chemistry of 19 lakes was carried ou...

Sedimentary diatoms in inferring trophic status and limnological changes in boreal lakes Miettinen, Juha O. Sedimentary diatoms in inferring trophic status and limnological changes in boreal lakes. – Analyses of sedimentary diatoms were used for inferring reference (pre-impact) conditions and limnological changes in eastern Fennoscandian lakes. Long-term limnological variation was studied from ...

In this study, Dunaliella has been isolated in Jun. 2014 from Hoz-e Soltan and Aran-va-Bidgol salt Lakes (Iran). The isolates have been identified morphologically with the aid of simple light and invert microscope after isolation and purification on their specific medium (Moh202). By using molecular techniques such as polymerase chain reaction (PCR) and amplification of 18S rDNA gene primers, f...