soil productivity and plant growth are usually affected by biological activities of earthworms. the objective of this study was a comparative evaluation of earthworm abundances in 20-year-old plantations of alder, oak, maple and cypress with the adjacent natural mixed broad-leaved deciduous forest in the caspian region of iran. in this research one sample plot, each 1 ha; was selected in every ...

Alpha-linolenic acid and linoleic acid isolated from Ulva fasciata showed toxic effects on red tide phytoplankters in a concentration-dependent manner. Among six species tested, raphidophycean flagellate Heterosigma akashiwo was the most susceptible to these fatty acids, and 50% lethal concentrations (LC50) of alpha-linolenic acid and linoleic acid were estimated to be 0.58 and 1.91 microg/ml r...

Aquatic organisms, ranging from bacteria to fish, living in clear lakes are presently receiving damaging levels of UV radiation. Photoreactivation is a light-dependent mechanism by which some organisms deal with DNA damage caused by UV radiation. Yet, photoreactivation is a mechanism that confounds long-term predictive modeling of UV effects on the survival of these organisms. Here we show that...

The chemical ecology of rotifers has been little studied. A yet unknown property is presented within some monogonant rotifers, namely the ability to produce an exogenic filamentous biopolymer, named ‘Rotimer’. This rotifer-specific viscoelastic fiber was observed in six different freshwater monogonants (Euchlanis dilatata, Lecane bulla, Lepadella patella, Itura aurita, Colurella adriatica and T...

Abstract One way to cope with predictable environmental fluctuations that affect several generations of individuals is through nongenetic transgenerational effects. Ancestors match the phenotype their descendants environment latter are expected experience. In facultatively sexual rotifer life cycles, sex linked production diapausing eggs, which enables survival between growing seasons. some spe...

We tested the hypothesis that rotifer species in the microand mesozooplankton are a potential food source for zebra mussels. We labeled phytoplankton with 14C, fed them to two species of rotifers (140–210 mm length) that were previously found abundantly in the Hudson River and had declined following a zebra mussel invasion, and estimated the assimilation of carbon. Assimilation efficiencies wer...

Solar simulator irradiation of an aqueous suspension of prednisone, a widely prescribed drug, produces seven photochemical derivatives. The compounds have been identified on the basis of their physical features. All the chemicals have been tested to evaluate their toxic effects on freshwater organisms from different trophic levels. The rotifer Brachionus calyciflorus and two crustaceans, the cl...

In contrast to the highly conserved mitogenomic structure and organisation in most animals (including rotifers), the two previously sequenced monogonont rotifer mitogenomes were fragmented into two chromosomes similar in size, each of which possessed one major non-coding region (mNCR) of about 4-5 Kbp. To further explore this phenomenon, we have sequenced and analysed the mitogenome of one of t...