Our analysis uses data from lake sediment cores, stand inventories, and historical records.
"I think the traditional interpretation of the Ediacaran rocks [as being derived from marine sediments] still stands".
This index is based on the relative abundance of di-unsaturated alkenones (C37:2) and tri-unsaturated alkenone (C37 3) in the sediment, and UK' 37 stands for "unsaturated ketones with 37 carbon atoms".
In the context of our work exploring the role of Sparganium erectum as a physical ecosystem engineer, we aimed to test our hypothesis that the root and rhizome biomass of this species would be largely confined to the uppermost sediment layers, thereby having the effect of reinforcing newly deposited material and facilitating the growth of in-channel macrophyte stands and sediment accumulations.
The leaching of shells due to exposure of marine sediments at sea-level low stands raises the Mg2+ and Ca2+ concentrations.
Pioneer riparian trees which establish in river active tracts on gravel bars enhance fine sediment retention during high flows within their stands and in their lee side, forming obstacle marks.
The researchers melted parts of the cores, filtered the water, and put the sediments under a microscope, selecting particles that stood out because of their shape or bright color.
Lateral variability of rhizoliths in Type A paleosols, and their close association with fluvial channel-fill sediments suggests they are the roots of grove stands of phreatophytic vegetation that grew within unstable anabranching stream systems.
Establishing fast growing willow stands on land disposed contaminated dredged sediment can result in the revaluation of this material and opens possibilities for phytoremediation.
Furthermore, dense stands strongly reduced water layer oxygen concentrations, which stimulated sediment phosphorus mobilisation, and increased carbon dioxide concentrations, which enhanced underwater photosynthesis.
