In situ measurements and model calculations of primary production in turbid waters

Parameterization of chlorophyll-specific phytoplankton absorption coefficients for productive lake waters

“…The chlorophyll-specific phytoplankton absorption coefficient [a * ph (λ) -the amount of light absorbed by a unit of pigment quantity at different wavelengths] provides also information on phytoplankton community structure and is regarded as a key input parameter in primary production models (Longhurst et al, 1995;Westberry et al, 2005;Arst et al, 2008).…”

Quantification of a Primary Production Model Using Two Versions of the Spectral Distribution of the Phytoplankton Absorption Coefficient

“…However, drawing up a fully theoretical model is rather complicated, and many different kinds of initial parameters are needed for computations. Despite the simplicity of our semi-empirical models, a comparison of measured and modeled primary production gave R 2 in the range of 0.85-0.96; p was always <0.00001 [1]. In this study, the concentrations of chlorophyll ranged mostly from 10 to 200 mg m −3 (maximum even 389 mg m −3 ) [1].…”

“…Despite the simplicity of our semi-empirical models, a comparison of measured and modeled primary production gave R 2 in the range of 0.85-0.96; p was always <0.00001 [1]. In this study, the concentrations of chlorophyll ranged mostly from 10 to 200 mg m −3 (maximum even 389 mg m −3 ) [1]. The algorithm of Bricaud et al [2] was obtained using mainly sea data where the concentration of chlorophyll was less than 25 mg m −3 .…”

“…The algorithm (and corresponding coefficients) for calculating the spectra of the specific absorption coefficient of light by phytoplankton, a 0 ph l ð Þ, was taken from Bricaud et al [2]. The detailed description of these models, including regression analysis and estimation of errors, was presented in Arst et al [1]. The initial data for calculations were: (a) incident onto the water surface solar irradiance in the photosynthetically active region between 400 and 700 nm (PAR), denoted as q PAR,z00 , (b) the concentration of chlorophyll a (C chl ), and (c) the diffuse attenuation the coefficient of light (K d ).…”

“…Two versions (spectral and integral) of a semi-empirical model for calculation of the vertical profiles of primary production in lakes were elaborated by Arst et al [1]. Quantification of these models was for 4.2 to 389 mg m −3 for chlorophyll a concentration range and 0.1 to 3 m for Secchi depth in the Estonian lakes Peipsi, Võrtsjärv, and Harku.…”