نتایج جستجو برای: urmia lake sediments
تعداد نتایج: 69393 فیلتر نتایج به سال:
statistical modeling of future lake level under climatic conditions, case study of urmia lake (iran)
the present research focuses on the changes of urmia lake level. for this purpose, two timescales have been considered. the trend changes of temperature, precipitation rate and quantitative values of climate type for the observational period from 1968 to 2011 (past scale) and from 2011 to 2100 (future scale) have been analyzed. general circulation model (gcm) is considered for simulating the va...
Citation: Hamilton PB, Lavoie I, Alpay S and Ponader K (2015) Using diatom assemblages and sulfur in sediments to uncover the effects of historical mining on Lake Arnoux (Quebec, Canada): a retrospective of economic benefits vs. environmental debt. Front. Ecol. Evol. 3:99. doi: 10.3389/fevo.2015.00099 Using diatom assemblages and sulfur in sediments to uncover the effects of historical mining o...
Methylmercury has been thought to be produced predominantly by sulfate-reducing bacteria in anoxic sediments. Here we show that in circumneutral pH sediments (Clear Lake, CA) application of a specific inhibitor of sulfate-reducing bacteria at appropriate concentrations typically inhibited less than one-half of all anaerobic methylation of added divalent mercury. This suggests that one or more a...
Lakes are very interesting sedimentary environments for the study of ancient climate, changes in sedimentary environments and lake level changes. Lake Zeribar is situated in the Zagros Mountains, Kurdistan, Iran. The main purpose of this research is to examine grain size sediments, geochronology and clay mineralogy accumulated in Zeribar Lake in order to check the water level fluctuations, clim...
This work was conducted to examine the composition and electrochemical activity of the bacterial community inhabiting lake Furnas sediments (Azores). Fingerprinting analysis of the bacterial 16S rRNA gene fragment was done by denaturing gradient gel electrophoresis. The sequences retrieved from lake Furnas sediments were affiliated to Bacteroidetes/Chlorobi group, Chloroflexi, Alfa-, Delta-, an...
Assessment of the Mutagenic Potential of Skadar Lake Sediments Using the Salmonella Microsomal Assay
Organic extracts of sediments from Skadar Lake (National park and protected RAMSAR site) were investigated for their mutagenic potential using Salmonella typhimurium TA98 and TA100 strains in the presence and absence of metabolic activation. Five different concentrations of sediment extracts from five different sampling sites were assayed, and mutagenic results were obtained for both strains. T...
Polycyclic aromatic hydrocarbons (PAH) in lake sediments and nearby soils of two European high mountain regions, Pyrenees and Tatra, have been studied. Similar mixtures of parent PAH were observed in all cases, indicating predominance of airborne transported combustion products. Nevertheless, the composition of these atmospherically long-range transported PAH was better preserved in the superfi...
In response to nuisance growths of algae and vascular plants, such as dioecious hydrilla ( Hydrilla verticillata L.f. Royle), copper formulations have been applied in lakes and reservoirs for a number of years. Concerns have arisen regarding the long-term consequences of copper applications and those concerns have appropriately focused on sediment residues. In this study, we evaluated the toxic...
Polycyclic aromatic hydrocarbons (PAHs) in the priority controlling list of US EPA were systematically evaluated in surface sediments in Dianchi Lake and its estuaries. Total PAH concentrations (ΣPAHs) varied from 210 to 11,070 ng/g dry weight (d.w.) in Dianchi Lake, and from 230 to 12,271 ng/g d.w. in the estuaries. ΣPAHs in sediments from Caohai section were higher than those from Waihai sect...
Lakes have long been recognized as being rich storehouses of environmental information. A lake basin collects water, but also sediment, much of which has been weathered and transported via fluvial processes from the near and far reaches of its drainage basin. The amount of water held in a lake is recorded on the landscape in coastal erosional and depositional landforms created at the water’s ed...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید