The eddy correlation technique has become a widely used approach to measure ecosystem scale fluxes in aquatic benthic environments; however, there are few theoretical studies designed to guide deployment planning, the characterization of flux variability, or how to correctly interpret measured fluxes. Here, a three-dimensional numerical model for the turbulent transport and mixing in the near-b...

Benthic macrofauna are used extensively for environmental assessment, but the area sampled and sieve sizes used to capture animals often differ among studies. Here, we sampled 80 sites using 3 different sized sampling areas (0.1, 0.05, 0.0071 m(2)) and sieved those sediments through each of 2 screen sizes (0.5, 1 mm) to evaluate their effect on number of individuals, number of species, dominanc...

The increase of anthropogenic pressures on the marine environment together with the necessity of a sustainable management of marine living resources have underlined the need to map and model coastal environments, particularly for the purposes of spatial planning and for the implementation of integrated ecosystem-based management approach. The present study compares outputs of a process-driven b...

Two toxic-unit models that estimate the toxicity of trace-metal mixtures to benthic communities were compared. The chronic criterion accumulation ratio (CCAR), a modification of biotic ligand model (BLM) outputs for use as a toxic-unit model, accounts for the modifying and competitive influences of major cations (Ca²(+), Mg²(+), Na(+), K(+), H(+)), anions (HCO₃⁻, CO²⁻₃ ,SO²⁻₄, Cl⁻, S²⁻) and dis...

Turfs are widespread assemblages (consisting of microbes and algae) that inhabit reef systems. They are the most abundant benthic component in the Abrolhos reef system (Brazil), representing greater than half the coverage of the entire benthic community. Their presence is associated with a reduction in three-dimensional coral reef complexity and decreases the habitats available for reef biodive...

Temporal variations in the diatom benthic propagule (DBP) community and its role in the phytoplankton community in a monsoon-affected tropical estuary, Zuari estuary, Goa (India) is presented. The DBP from the sediments was enumerated using an extinction dilution method (Most Probable Number method), which allows estimation of resting stages through examination of germinated vegetative cells in...

The dependency of walruses on sea ice as habitat, the extent of their feeding, their benthic bioturbation and consequent nutrient flux suggest that walruses play a major ecological role in Beringia. This suggestion is supported by several lines of evidence, accumulated during more than three decades of enquiry and leading to the hypothesis that positive feedbacks of walrus feeding strongly infl...

The direct harmful effects of ultraviolet radiation (UVR) on benthic and planktonic organisms have been well studied in aquatic systems. Less clear, however, is how UVR might affect aquatic communities through its effects on trophic interactions. The focus of this study was twofold: first, to examine the direct effect of UVR on benthic invertebrates and epilithon, the rock-dwelling matrix of al...

The spatial effects of 2 tuna farms on the benthic community were investigated in the Eastern Mediterranean during the fattening period. The impact on benthic fauna was assessed in the vicinity of the fish farms (beneath and at various distances from the cages) using a variety of benthic indicators used for the implementation of the EU Water Framework Directive (WFD). There was a general consen...

Anthropogenic acidification has deleterious effects on both structure and functioning of surface water ecosystems. This study examined how it may affect the leaf decomposition rate and the community structure and activity of decomposers in both benthic and hyporheic zones of five headwater streams along an acidification gradient from highly acidic (pH 4.6) to circumneutral (pH 7.4). Overall, re...