Denitrification is an important microbial process in aquatic ecosystems that can reduce the effects of eutrophication. Here, quantification and pyrosequencing of nirS, nirK, and nosZ genes encoding for nitrite and nitrous oxide reductases was performed in sediment samples from four boreal lakes to determine the structure and seasonal stability of denitrifying microbial populations. Sediment qua...

Thanks to the precise core dating and the high sedimentation rate of the drilling site (Gallipoli Terrace, Ionian Sea) we were able to measure a foraminiferal δ(18)O series covering the last 2,200 years with a time resolution shorter than 4 years. In order to support the quality of this data-set we link the δ(18)O values measured in the foraminifera shells to temperature and salinity measuremen...

This paper describes a study of the occurrence, levels and temporal evolution of PAHs in a bay characterized by persistent chronic impacts. A total of 40 samples, 20 of sediment and 20 of water, were taken at each of five different stations, in four sampling campaigns. Analyses of pollutants have been made using GC-MS. Results indicate that in a coastal environment subjected to chronic pollutio...

Although environmental DNA (eDNA) has been used to infer the presence of rare aquatic species, many facets of this technique remain unresolved. In particular, the relationship between eDNA and fish distribution is not known. We examined the relationship between the distribution of fish and their eDNA (detection rate and concentration) in a lake. A quantitative PCR (qPCR) assay for a region with...

An unditched salt marsh-creek drainage basin (Holland Glade Marsh, Lewes, Delaware) has a sedimentation rate of 0.5 cm year-l. During normal, storm-free conditions, the creek carries negligible amounts of sand and coarse silt. Of the material in the waters flooding the marsh surface, over 80% disappears from the floodwaters within 12 m of the creek. About one-half of the lost material is theore...

The distribution of Clostridium botulinum in the natural environments of Denmark, The Faroe Islands, Iceland, Greenland, and Bangladesh was examined. A total of 684 samples were tested. Type E was found in 90% of samples from the aquatic environment of Denmark, including sediments from young artificial lakes, and in 86% of samples from the marine environment of Greenland. Type E was not found i...

Clastic sediments deposited at the bottom of vertical, nearly 1000 m deep Njemica Cave (Biokovo Mountain, Croatia) were analysed. Owing to vertical morphology cave, occurrences clastic are sparse. Small, up decimetre-thick, undisturbed sediment accumulations situated near siphon lake revealed interesting palaeontological and mineralogical data. These data used as a useful proxy for discussing d...

Organic matter steadily accumulates in eutrophic lakes as a result of deposition of detrital tissue from algae and aquatic macrophytes and the slow rate of anaerobic decomposition. The rate of organic matter decomposition is affected by the nature of the sediment C (electron donor) and supply of electron acceptors. Batch incubation experiments were conducted to determine the rate and extent of ...

Index words: Reservoir sedimentation Pb-210 dating Sediment retention Cs-137 dating The singlemost important factor affecting the longevity of US dams is sedimentation, reducing and perhaps eliminating the reservoir capacity for future sediment storage and floodwave attenuation. A better understanding of the sedimentation rates and sediment dynamics is required for a better management of these ...

-Pyramid Lake, a salt lake in Nevada, has undergone a 30~ reduction in volume over the past 100 yr due to diversion of river inflow for irrigation of farmland. This has altered the depositional-benthic environment and possibly has changed the overall aquatic environment of Pyramid Lake as indicated by changes in the hydrocarbon and monocarboxylic acid content in a sediment core. In the top 30 c...