A novel 3D volumetric method for directly quantifying porosity and pore space morphology in flocculated suspended sediments.

Flocculated suspended sediments (flocs) are found in a variety of environments globally, and their transport and behavior bear substantial importance to several industries including fisheries, aquaculture, and shipping. Additionally, the modelling of their behavior is important for estuarine and coastal flood prediction and defence, and the process of flocculation occurs in other unrelated industries such as paper and chemical production. Floc porosity is conventionally assessed using inferential indirect or proxy data approaches.

A structure-function based approach to floc hierarchy and evidence for the non-fractal nature of natural sediment flocs.

Natural sediment flocs are fragile, highly irregular, loosely bound aggregates comprising minerogenic and organic material. They contribute a major component of suspended sediment load and are critical for the fate and flux of sediment, carbon and pollutants in aquatic environments. Understanding their behaviour is essential to the sustainable management of waterways, fisheries and marine industries.

Quantifying the Structure and Composition of Flocculated Suspended Particulate Matter Using Focused Ion Beam Nanotomography.

Suspended particulate matter (SPM) is present in the natural aquatic environment as loosely bound aggregates or "flocs" and is responsible for the transport and fate of sediment, carbon, nutrients, pollutants, pathogens and manufactured nanoparticles from catchment to coast. Accurate prediction of SPM hydrodynamics requires the quantification of 3D floc properties (size, shape, density and porosity) that span several spatial scales. Yet, current techniques (video camera systems, optical microscopy and transmission electron microscopy, TEM) can only provide 2D simplifications of size and shape with a spatial resolution gap between the "gross" (>100s μm) and nanoscale (<1 μm).