The Ponto-Caspian amphipod Obesogammarus obesus (Sars, 1894) was first recorded in the Rhine River near Koblenz, Germany in October 2004. Additional records of small numbers of O. obesus from the same location in 2005 and 2006 indicate that this alien species may have become established in the central section of the Rhine River. Ship transport via the Main-Danube Canal, connecting the Danube ba...

A total of 48 female spirlins Alburnoides sp. from the Kesselian stream (South Caspian Sea basin, northern Iran) were examined during a period from July 2008 to June 2009 to obtain data on fecundity, and to determine the spawning season of this carp. The mean absolute fecundity of females spirlin was 1722.92 (653.88) eggs. The fecundity has positive correlation with the size of the female. The...

The study concerns the kinetics of cellular proliferation in the different cell populations of the normal and regenerating rat liver. A detailed analysis is presented, which includes techniques of in vivo labeling of DNA with tritiated thymidine and high-resolution radioautography, of the temporal and spatial patterns of DNA synthesis and cell division in the parenchymal cells, littoral cells, ...

The continuous increase in the number of reservoirs globally has raised important questions about the environmental impact of their greenhouse gases emissions. In particular, the littoral zone may be a hotspot for production of greenhouse gases. We investigated the spatiotemporal variation of CO2 flux at the littoral zone of a Chinese reservoir along a wet-to-dry transect from permanently flood...

Understanding how a monophyletic lineage of a species diverges into several adaptive forms has received increased attention in recent years, but the underlying mechanisms in this process are still under debate. Postglacial fishes are excellent model organisms for exploring this process, especially the initial stages of ecological speciation, as postglacial lakes represent replicated discrete en...

Tourists can adversely influence the ecology of oligotrophic lakes by increasing algal production via direct nutrient inputs and/or re-suspension of sediments. To assess the influence of tourists on food web dynamics, we used natural abundance stable isotopes of carbon and nitrogen to calculate the relative importance of autochthonous and allochthonous carbon sources to littoral zone food webs ...

A solid-phase extraction (SPE) method for sample clean-up and preconcentration followed by reversed-phase high-performance liquid chromatography (RP-HPLC) with uv detection is reported for determination of polycyclic aromatic hydrocarbons (PAHs) in the caspian seawater. A good resolution was obtained using acetonitrile:water (40:60) as mobile-phase for separation of these compounds. The effect ...

According to the increased probability of the presence of nanomaterials in the aquatic ecosystems, the present study examined the toxicity of three engineered silver nanoparticles (AgNPs) as well as silver ions in the Pontogammarus maeoticus, a brackish water benthic organism living in the littoral zone of the Caspian Sea. The animals were acutely exposed to different concentrations of two comm...