Measuring Particle Size Distribution in Natural Waters

The LISST-200X measures the size distribution and concentration of suspended particles directly in water. Using laser diffraction, it measures how particles scatter light and inverts that scattering pattern into a particle size distribution and volume concentration. The instrument measures particles from 1 µm to 500 µm.

LISST-200X in frame horisontal

Core LISST-200X outputs include particle volume concentration, particle size distribution, and beam attenuation. From these measurements, users can calculate additional parameters such as mean and median particle size. These data help scientists characterize suspended particles which may affect water quality, ecological and biological processes, environmental conditions, and sediment transport.

Typical users include university researchers—such as oceanographers, limnologists, biologists, geographers, geologists, and sedimentologists—as well as government agencies, environmental monitoring organizations, and consultants.

The LISST-200X in-situ size and concentration data is used to validate and support other particle measurements obtained with optical, acoustic, imaging, and remote-sensing methods. Other major application areas include sediment dynamics, flocculation, contaminant transport, and biological or biogeochemical particle studies. In rivers, estuaries, coastal waters, and the ocean, the instrument supports studies of resuspension, plume transport, stratification, and hydrodynamic controls on suspended sediment. In flocculation research, it helps quantify aggregation and breakup, characterize effective particle size and morphology, and relate particle structure to settling behavior. For contaminants such as microplastics and oil, LISST-200X measurements describe dispersion, aggregation, transport, weathering, and remediation processes. In biological and biogeochemical work, the instrument supports studies of plankton, cyanobacteria, organic matter, marine snow, and carbon-related particle properties.