Modeling spectral diffuse attenuation, absorption, and scattering coefficients in a turbid estuary

Abstract

Spectral diffuse attenuation coefficients were measured in the Rhode River and Chesapeake Bay, Maryland, on 28 occasions in 1988 and 1989. The model of Kirk was used to extract scattering and absorption coefficients from the measurements in waters considerably more turbid than those in which the model was previously applied. Estimated scattering coefftcients were linearly related to mineral suspended solids. Estimates of total absorption coefficients were decomposed as the sum of contributions by water, dissolved organic matter, phytoplankton chlorophyll, and particulate detritus, each having a characteristic spectral shape. The 1988 data were used to develop a model of scattering and absorption coefficients based on the specific curves regressed against water-quality parameters. Diffise attenuation coefficients in the 1989 data ranging from 1 to 10 m-l and photic depths ranging from < 1 to 4.5 m were predicted with a C.V. of about 25%.The problem of estimating concentrations of water-quality constituents from optical measurements was indeterminate due to the similarity in shape of the specific curves of dissolved substances and depigmented particulates. Chlorophyll concentration could be estimated because it was strongly related to water-corrected absorption in the 670-nm waveband, but several outliers occurred due to biological variability in specific absorption of pigments.

Estimating specific inherent optical properties of tropical coastal waters using bio-optical model inversion and in situ measurements: case of the Berau estuary, East Kalimantan, Indonesia

“…Its value (0.019-0.027 m 2 mg -1 ) is similar to what has been reported elsewhere. For example, Prieur & Sathyendranath (1981), Sathyendranath et al (1987), and Gallegos & Correl (1990) found that a Chl * for oceanic and coastal waters varies from 0.01 to 0.047 m 2 mg -1 , whereas Smith & Baker (1981) found that a Chl * varied between 0.039 and 0.168 m 2 mg -1 . On the other hand, Heege , in Albert & Mobley, 2003 and Le et al (2009) Table 3).…”

Impact of the Spring 2000 phytoplankton bloom in Chesapeake Bay on optical properties and light penetration in the Rhode River, Maryland

“…1). The system is shallow (mean depth 2 m, maximum depth 4 m), turbid (Gallegos et al 1990), and eutrophic (mean summer chlorophyll concentration ϭ 20 to 40 mg m Ϫ3 , Jordan et al 1991b;Gallegos and Jordan 1997). Salinity varies seasonally and spatially from 0 to 14 at the upstream stations and from about 2 to 20 at the mouth, depending on flow of the Susquehanna River, the main freshwater source to the upper Chesapeake Bay (Schubel and Pritchard 1986;Jordan et al 1991a).…”

“…Samples for chlorophyll and species identification were collected from the Secchi depth using a Labline Teflon sampler. An additional sample for chlorophyll and nutrient concentrations was collected by slowly lowering and raising the sampler from the surface to the bottom as it filled (Gallegos et al 1990). Vertically integrated samples give a better indicator of total water column pigment biomass whenever a subsurface peak is present (Gallegos et al 1990).…”

“…An additional sample for chlorophyll and nutrient concentrations was collected by slowly lowering and raising the sampler from the surface to the bottom as it filled (Gallegos et al 1990). Vertically integrated samples give a better indicator of total water column pigment biomass whenever a subsurface peak is present (Gallegos et al 1990). Samples were placed in a cooler on the boat and transported to the laboratory for filtration, which was generally completed within 3 h of sampling.…”

Sustainable Seagrass Restoration in the Virginia Coastal Bays

“…Dennison et al (1993) found the minimum water quality characteristics using water column chlorophyll a (15 μg/L), total suspended solids (15 mg/L), dissolved inorganic nitrogen (DIN) (10 μM) and dissolved inorganic phosphorous (DIP) (0.67 μM) to sustain submerged aquatic vegetation (SAV) in the Chesapeake Bay and its tributaries. modified an optically active constituent model (Gallegos et al 1990) to find the levels of optically active constituents, non-algal particulates and phytoplankton, needed for seagrass growth in order to set goals for ecosystem managers. They verified their model at the maximum depth limits for seagrasses in the Albemarle-Pamlico Sound off the coast of North Carolina, USA.…”