The sediment of a river having ''good ecological status" turned out to be toxic to midge Chironomus riparius larvae: Implication for environmental monitoring?

Globally, monitoring of the surface waters is largely limited to the physico-chemical analysis of water in rivers and lakes. Sediment state in the aquatic systems including sediment chemical content or the structure and diversity of benthic communities or ecotoxicological studies with natural sediments remains largely overlooked by the monitoring programs. Hence we assessed the potential toxicity of three riverine sediments on the life-cycle traits (emergence and reproduction) of midge Chironomus riparius via an ecotoxicological testing method over two generations (according to OECD test 233 guidelines).

The state of the population of narrow-clawed crayfish in Lake Sevan (Armenia) under multiple stress conditions.

The narrow-clawed crayfish is a crayfish species that was accidentally introduced into the ecosystem of Lake Sevan in the 1980s. Soon it became one of the most preferred fisheries in the lake and an important link in the food chain by successfully replacing the endemic fish subspecies Sevan khramicarp (Capoeta sevangi, De Filippi, 1865) in the chain of detritivores. However, recently, the stock declines dramatically, associated with two main threats: the impact of burn-spot disease and an increase in fishing pressure on its population.

Assessment of the mutagenic potential of the water of an urban river by means of two Tradescantia-based test systems.

River pollution can be caused by anthropogenic or natural factors. When testing water quality for the presence of toxic substances, higher plants as bioindicators for the genotoxic effects of complex mixtures are effective and appropriate. Hence, in this work the Tradescantia (clone 02) stamen hair mutations (Trad-SHM) and Tradescantia micronuclei (Trad-MCN) were used to determine mutagenic and clastogenic potential of an urban river.

Caucasian treasure: Genomics sheds light on the evolution of half-extinct Sevan trout, Salmo ischchan, species flock.

Five ecologically and phenotypically divergent ecomorphs of the genus Salmo are known from a landlocked alpine lake in the Caucasus, Lake Sevan. It is an example of sympatric diversification within a species-rich lineage with predominate mode of speciation being allopatric. The diversification of Sevan trouts was accompanied by spawning resource partitioning.

Ingestion and effects of virgin polyamide microplastics on Chironomus riparius adult larvae and adult zebrafish Danio rerio.

Secondary microplastics (MP) produced by fragmentation of plastic in the environment or as a result of human activities can easily be taken up by organisms. The harmful effects of MP depend on e.g.