Kelly Thomas, Biological Oceanographer

A longtime user of LISST instruments, the University of Alaska Fairbanks has been using the new, LISST-200X-style 4,000m rated LISST-Deep from Sequoia Scientific, Inc. The LISST-Deep instrument measures in-situ particle size distribution from 1 um to 500 um, optical transmission, and the optical volume scattering function (VSF) at depths down to 4,000 meters.

Sequoia asked Dr. Thomas Kelly (Postdoctoral Fellow), two questions specific to the use and application of this instrument, see his Q&A comments below:

Question 1: What problems are you trying to solve by using the LISST-Deep?

“The Gulf of Alaska is a rich mosaic of biological diversity underpinned by complex physical drivers and circulation. One of our principal goals is to deconstruct the marine environment into individual processes, such as how organic matter is formed, transported, reshaped, and ultimately supplied to deep sea and benthic (seabed) communities. Many of the tools used to investigate these processes are time consuming and of low resolution; alternatively, the LISST platform permits high resolution snapshots of the organic matter that couples easily to our biological, chemical, and physical observations.”

Question 2: How did you conclude that the LISST-Deep would help you solve problems and be useful for future research before purchasing?

“We needed a system that could be reliable in all weather conditions and simply integrated into our existing system. Often time is a limited factor for our field work, so a system like the LISST allowed us to get more data with fewer resources than alternatives. Information from the LISST allows us to start integrating data from various parts of the ecosystem into a cohesive whole since the size range of the LISST is well suited to filling in the gap below traditional imaging systems (i.e. >200 um).”

“The LISST system can also be deployed across multiple platforms including our new Deep-focus Plankton Imager (DPI), which is a towed vehicle that is outfitted with a wide variety of ecosystem sensors including the LISST (small particles), three shadowgraph cameras (large particles and small organisms) and active acoustics (fish-finder). Such a system allows us to ask questions about the entire biological community instead of just small parts of it.”

Thanks to Dr. Kelly for the order and the explanation.

Thomas Kelly, Postdoctoral Fellow, Biological Oceanography – UAF College of Fisheries and Ocean Sciences – Fairbanks, Alaska, USA (2023)