Literature data on benthic dissolved iron (DFe) fluxes (μmolm 2 d ), bottom water oxygen concentrations (O2BW, μM), and sedimentary carbon oxidation rates (COX, mmolm 2 d ) from water depths ranging from 80 to 3700m were assembled. The data were analyzed with a diagenetic iron model to derive an empirical function for predicting benthic DFe fluxes: DFe flux 1⁄4 γ tanh COX O2BW where γ (= 170μmo...

abstractthe aim of this study was to determine the ecology of the ostracoda species in the sediments collected from the erdek bay and to observe the relationship between ecological parameters with the number of ostracoda species and individual numbers. sediment and water samples have been collected seasonally from 8 stations of the study area from six different depths (0.3; 1; 5; 10; 20; 30 m)....

While biodiversity in deep-sea soft sediments appears to be high, little is known about diversity levels on deep-sea hard substrates. To determine the contribution of potentially abundant whale-skeleton habitats to deep-sea biodiversity, we compare the local macrofaunal species richness and composition on 3 sulfide-rich whale skeletons to assemblages from vents, seeps, and other deepsea hard su...

The marine environment represents a largely untapped source for isolation of new microorganisms with potential to produce biologically active secondary metabolites. Among such microorganisms, Gram-positive actinomycete bacteria are of special interest, since they are known to produce chemically diverse compounds with a wide range of biological activities. We have set out to isolate and characte...

Methylmercury (MeHg) bioaccumulation in marine food webs poses risks to fish-consuming populations and wildlife. Here we develop and test an estuarine mercury cycling model for a coastal embayment of the Bay of Fundy, Canada. Mass budget calculations reveal that MeHg fluxes into sediments from settling solids exceed losses from sediment-to-water diffusion and resuspension. Although measured met...

Marine bacteria regulate fluxes of matter and energy essential for pelagic and benthic organisms and may also be involved in the formation and maintenance of commercially valuable abyssal polymetallic nodules. Future mining of these nodule fields is predicted to have substantial effects on biodiversity and physicochemical conditions in mined areas. Yet, the identity and distributions of bacteri...

Morphological divergence was evident among three sympatric morphs of Arctic charr (Salvelinus alpinus (L.)) that are ecologically diverged along the shallow-, deep-water resource axis in a subarctic postglacial lake (Norway). The two deep-water (profundal) spawning morphs, a benthivore (PB-morph) and a piscivore (PP-morph), have evolved under identical abiotic conditions with constant low light...

water and sediment samples were collected from six different stations, located along the nil river between february and june 2015. concentrations of cadmium, lead, zinc, and copper were determined. the extent of the sediment pollution was assessed, using the multiple pollution indices, namely contamination factor (cf), pollution load index (pli), and the geoaccumulation index (igeo). the result...

pollution of marine waters is one of the important issues that has a irreparable effects. also, in the organic oil pollutants, due to inappropriate effects on the environment and humans health and ability to create cancer, hydro carbons of polycyclic (pahs) and heavy metals (ni,hg,v) have a particular importance. according to the importance of study of the environ mental contaminants in the fou...

The distribution of redox-sensitive metals in sediments is potentially a proxy for past ocean ventilation and productivity, but deconvolving these two major controls has proved difficult to date. Here we present a 740 kyr long record of trace element concentrations from an archived sediment core collected at ~15S on the western flank of the East Pacific Rise on 1.1 Ma old crust, and underlying ...