Dimensionless indices, in particular the Wedderburn and Lake numbers, which are the ratios of the buoyancy forces, which resist mixing to the inertial forces that induce mixing, can be used to predict whether the upper mixed layer of lakes will mix primarily by cooling and wind stirring or whether entrainment will be facilitated by shear at the base of the mixed layer.
Metals in the smoke from a smelter rain down and get trapped in successive layers of lake sediment.
Only slightly lower levels of microplastics (0.355 mm to approx. 5 mm) were recorded in the surface layer of Lake Hovsgol, a large mountain lake in northern Mongolia [103].
Sediment-laden riverine floods transport large quantities of dissolved oxygen into the receiving deep layers of lakes.
During that period the hydrogen sulfide was detected only in the bottom layer of the lake.
De Heem thus indicated the lay in of the tulip with a layer of red lake, lead white and a small amount of vermilion red (HgS).
Besides their remarkable preservation, which even saved traces of delicate structures like air bladders in fish, researchers have often found an unexpected juxtaposition of creatures in the same layer of ancient lake sediment.
The highest concentration of iodide was detected 1 m below the chemocline, coinciding with the local minimum in sulfate concentrations (Figure 3d), and not in the bottom layer of the lake.
The two sampling zones shared about 30% of OTUs (Table S1), indicating the ability of some picoeukaryotes to colonize the whole mixolimnic layer of the lake, regardless of oxygen constraints.
Three different depths were sampled for the oxic layer of the lake [i.e. 5 m (epilimnion), 9 10 m (metalimnion), and 30 m (hypolimnion)], and one depth (59 m) for the oxycline at three occasions (May , 24 June, 16 and July, 11 2005) (Fig. 1).
In a preliminary study of microplastic (0.3 5 mm) levels in the surface layer of Lake Geneva Switzerlandd), a microplastic concentration of 0.048 items/m2 was derived [141].
