A laboratory evaluation of the laser in situ scattering and transmissometery instrument using natural sediments

Traykovski, Peter; Latter, R.; Irish, James D.

doi:10.1016/s0025-3227(98)00196-0

Cited by 122 publications

(77 citation statements)

References 14 publications

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“…It is actually the geometric average of the upper and lower sizes of each size range. As noted in previous studies [11,62,63], LISST measurements at the smallest and largest size ranges may be not very steady due to the presence of particles outside of the measured size range. Thus, data of the smallest and largest size ranges were removed in the subsequent analysis.…”

Section: Lisst Measurementmentioning

confidence: 62%

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Qiu

Sun

et al. 2016

Remote Sensing

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Particle size distribution (PSD) is an important parameter that is relevant to many aspects of marine ecosystems, such as phytoplankton functional types, optical absorption and scattering from particulates, sediment fluxes, and carbon export. However, only a handful of studies have documented the PSD variability in different regions. Here, we investigate the PSD properties and variability in two shallow and semi-enclosed seas (the Bohai Sea (BS) and Yellow Sea (YS)), using in situ laser diffraction measurements (LISST-100X Type C) and other measurements at 79 stations in November 2013. The results show large variability in particle concentrations (in both volume and number concentrations), with volume concentrations varying by 57-fold. The median particle diameter (D v 50 ) from each of the water samples also covers a large range (22.4-307.0 µm) and has an irregular statistical distribution, indicating complexity in the PSD. The PSD slopes (2.7-4.5), estimated from a power-law model, cover nearly the entire range reported previously for natural waters. Small mineral particles (with large PSD slopes) are characteristic of near-shore waters prone to sediment resuspension by winds and tides, while large biological particles (with small PSD slopes) dominate the total suspended particulates for waters away from the coast. For the BS and YS, this study provides the first report on the properties and spatial variability of the PSD, which may influence the optical properties of the ocean surface and remote sensing algorithms that are based on estimations of particle concentrations and sizes.

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Section: Lisst Measurementmentioning

confidence: 62%

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Qiu

Sun

et al. 2016

Remote Sensing

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“…Six along river transects from the upper estuary in the Cam River (position A, Figure 1a) to the Nam Trieu mouth (position B, Figure 1a) or the reverse were performed with a total of 110 stations (see one of the 6 transects on Figure 1b; a kml file is provided as Supplementary Material). At each station, velocity profiles were measured with a 600 kHz acoustic Doppler current profiler (ADCP RDI Workhorse in bottom tracking mode) configured for a 0.3 m bin size; depth profiles of water temperature, salinity and turbidity were measured by a Compact-CTD (ASTD687, Alec Electronics Co. (Nishinomiya, Japan), now released by JFE Advantech Co. (Nishinomiya, Japan) as Rinko-Profiler); depth profiles of floc size distribution and concentration were measured using an in situ laser scattering and transmissometry instrument with a 90% path reduction module (LISST-100X, Sequoia Scientific Inc. (Bellevue, WA, USA); e.g., [42,43]). The LISST of type B provided the volumetric particulate concentration in 32 logarithmically spaced size classes ranging from 1.25 to 250 µm and attenuation at λ = 660 nm.…”

Section: Field Datamentioning

confidence: 99%

“…Their sum is providing the SPM volume concentration (SPMVC). However, particles less than the smallest size class or bigger than the largest size class affect the measurements in the spectrum [42][43][44][45][46][47][48][49][50][51][52]. In this study, we followed the recommendation of former authors to remove the first and last classes for calculating the general slope of the particle size distribution and the mean apparent diameter D 50 [42][43][44][45][46][47][48][49][50][51][52].…”

Section: Spm Volume Concentration (Spmvc) and Particle Size Distributmentioning

confidence: 99%

Estuarine Turbidity Maxima and Variations of Aggregate Parameters in the Cam-Nam Trieu Estuary, North Vietnam, in Early Wet Season

Vinh¹,

Ouillon

2018

Water

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Abstract:This study aims at exploring the characteristic parameters of the Estuarine Turbidity Maxima (ETM) and at investigating their tidal variations within the Cam-Nam Trieu estuary (North Vietnam) during the early wet season. Six longitudinal river transects were performed at spring tide. Two types of ETM were observed: an upper well mixed ETM with high Suspended Particulate Matter (SPM) concentrations up to the surface at low salinity (0.11 to <1 psu), and a lower ETM confined in a bottom layer over stratified waters at salinities between~1 psu and 15 psu. Their length depended on the longitudinal salinity gradient and was highest at low tide than at high tide. D 50 of the flocs varied between 35 and 90 µm, their excess of density between 60 and 300 kg m −3 and their settling velocity ranged from 0.07 to 0.55 mm s −1 with values between 0.12 and 0.40 mm s −1 in the core of ETMs. The average fractal dimension of flocs was estimated to vary between 1.93 (at high tide) to 2.04 (at low tide).

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“…The instrument used here is a new version of Lisst-100, which is able to measure smaller particles (1.2-250 µm) with more resolution than those measured with its previous version (5-500 µm). The previous version of Lisst-100 has already been evaluated and found appropriate for measuring natural sediments (Traykovski et al 1999). In the present work, Lisst-100 has been also used to measure organic particles, such as photosynthetic sulphur bacteria (Chromatiaceae) and phytoplankton, and inorganic particles such as suspended sediments.…”

Section: Introductionmentioning

confidence: 96%

Evaluation of Laser In Situ Scattering Instrument for Measuring Concentration of Phytoplankton, Purple Sulfur Bacteria, and Suspended Inorganic Sediments in Lakes

et al. 2001

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A laser in situ scattering and transmissometry (Lisst-100) probe has been used for estimating the particle-size distribution of phytopankton, purple photosynthetic sulphur bacteria (Chromatiaceae), and suspended inorganic sediments in different lakes. Results from Lisst-100 have been compared to laboratory measurements, such as those obtained by using a Galai laser size analyzer (GL), an optical microscope (OM), and a flow cytometer (FC). Although all of these instruments were shown to provide reliable values of the particle number concentration for the given populations, the Lisst-100 was the fastest and most reliable instrument because it did not require manipulation of the samples-which is not the case of GL, OM and FC instruments -and avoided the tedious procedure of microscopic counts. The total particle volume concentration results obtained with Lisst-100 differed from those obtained with GL for populations with large and porous aggregates, such as phytoplankton cells. The difference was attributed to the breakage of fragile algal aggregates resulting from the measuring procedure used by GL. Although for suspended sediment particles both instruments gave the same results for the total particle volume concentration, the particle-size distribution obtained with GL was found always shifted to smaller diameters than with Lisst-100, probably because inorganic sediment particles present compact aggregates. When these aggregates break, they split into a high number of small particles that contribute the same to the total volume concentration as the previous aggregates. Finally, results of the total particle volume concentration with Lisst-100 were in accordance with those obtained with GL for the Chromatiaceae population, because cells remained in a dispersed phase. A good correlation was found between the total particle volume concentration of Chromatiaceae measured with Lisst-100 and the concentration of bacteriochlorophyll a (BChl a), which is the parameter habitually used to estimate the concentration of Chromatiaceae. Therefore, Lisst-100 was found to be a reliable instrument to estimate the Chromatiaceae concentration in aquatic ecosystems.

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A laboratory evaluation of the laser in situ scattering and transmissometery instrument using natural sediments

Cited by 122 publications

References 14 publications

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Variability of Particle Size Distributions in the Bohai Sea and the Yellow Sea

Estuarine Turbidity Maxima and Variations of Aggregate Parameters in the Cam-Nam Trieu Estuary, North Vietnam, in Early Wet Season

Evaluation of Laser In Situ Scattering Instrument for Measuring Concentration of Phytoplankton, Purple Sulfur Bacteria, and Suspended Inorganic Sediments in Lakes

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