Scattering properties of two blooming algae: Skeletonema costatum and Prorocentrum donghaiense

Abstract

Abstract: Phytoplankton is a major component of marine water, an insight investigation of its inherent optical properties is the foundation of understanding the principle of light transferring in water. In the last 30 years, focus was mainly on the absorption measurement and comparison of different algae, very few researchers had a detailed study on their scattering properties. In this paper, a method based on spectrometer was developed to measure the total scattering and backscattering coefficient of algae containing solution. The verification procedure of the method was carried out by measuring the scattering and backscattering results of polystyrene latex micro beads with known size distribution and refractive index. The results showed a maximum deviation of 4% for scattering in the visible spectrum and around 20% higher for backscattering in the red spectrum but quite good consistency in other regions. The method was then used to measure the scattering and backscattering features of two bloom algae in East China Sea: Skeletonema costatum and Prorocentrum donghaiense. It shows that the two algae had comparable amplitudes in both scattering and backscattering cross section, but Skeletonema costatum had a quite opposite scattering pattern to Prorocentrum donghaiense, whose scattering decreases with increasing wavelength. This could be attributed to the different cellular components which determine whether it follows normal or anomalous dispersion for the refractive index. Both algae have a regional minimum of scattering around 670 nm, which was due to the anomalous dispersion and the strong absorption of chlorophyll a. The backscattering cross section for the two algae were similar in both amplitude and spectrum pattern, Prorocentrum donghaiense had a higher but smoother backscattering spectrum. It'd demonstrated that the backscattering spectrum is well influenced by absorption of cellular pigments. Finally, the backscattering to scattering ratio was 0.723% for Skeletonema costatum and 1.104% for Prorocentrum donghaiense, the absolute value of backscattering cross section were 0.001 43 m²/mg and 0.001 74 m²/mg respectively.

Key words: laboratory measurement, Skeletonema costatum, Prorocentrum donghaiense, optical scattering properties

CLC Number:

P733.3⁺1

SHEN Yu-zhang, MAO Zhi-hua, TAO Bang-yi. Scattering properties of two blooming algae: Skeletonema costatum and Prorocentrum donghaiense[J]. Journal of Marine Sciences, 2013, 31(1): 45-52.

References

[1] CUI Ting-wei, ZHANG Jie, MA Yi, et al. Study of red tide spectral characteristics and its mechanism[J]. Spectroscopy and Spectral Analysis,2006,26(5):884-886.
崔延伟,张杰,马毅等,赤潮光谱特征及其形成机制[J].光谱学与光谱分析,2006,26(5):884-886.
[2] MOBLEY C D. Light and water: radiative transfer in natural waters[M]. US: Academic Press,1994:55-83.
[3] YANG Wei, CHEN Jin, Mausushita Bunki. Algorithm for estimating chlorophyll-a concentration in case II water body based on bio-optical model[J]. Spectroscopy and Spectral Analysis,2009,29(1):38-42.
杨伟,陈晋,松下文经,基于生物光学模型的水体叶绿素浓度反演算法[J].光谱学与光谱分析,2009,29(1):38-42.
[4] GORDON H R, MOREL A. Remote assessment of ocean color for interpretation of visible imagery: a review[M]. Berlin:Springer-Verlag,1983:114.
[5] MOREL A. Optical modeling of the upper ocean in relation to its biogenous matter content (case I waters)[J]. J. Geophys. Res,1988,93(10):749-768.
[6] PREISENDORFER R W. Hydrological optics(6 volumes)[M]. Honolulu, HA: US Department of Commerce,1976.
[7] GORDON H R, BROWN O B, EVANS R H, et al. A semi-analytic model of ocean color[J]. Journal of Geophysical Research,1988,93(10):909-924.
[8] GORDON H R, BROWN O B, JACOBS M M.Computed relationships between the inherent and apparent optical properties of a flat homogeneous ocean[J]. Applied Optics,1975,14:417-427.
[9] KIRK J T O. Dependence of relationship between inherent and apparent optical properties of water on solar altitude[J]. Limnology and Oceanography,1984,29:350-356.
[10] MOREL A, MUELLER J L. Normalized water-leaving radiance and remote sensing reflectance: bidirectional reflectance and other factors[M]//MUELLER J L,FARGION G S.Ocean Optics Protocols for Satellite Ocean Color Sensor Validation,Rev3,vol 2.NASA/TM-2002-210004. (Chapter 13),2002:183-210.
[11] MOREL A, GENTILI B. Diffuse reflectance of oceanic waters:its dependence on sun angle as influenced by the molecular scattering contribution[J]. Applied Optics,1991,30(30):4 427-4 438.
[12] BRICAUD A, MOREL A, PRIEUR L. Optical efficiency factors of some phytoplankters[J]. Limnology and Oceanography,1983,28(5):816-832.
[13] BRICAUD A, MOREL A. Light attenuation and scattering by phytoplanktonic cells: a theoretical modeling[J]. Applied Optics, 1986,25(4):571-580.
[14] TASSAN S, KARIMA A. Proposal for the simultaneous measurement of light absorption and backscattering by aquatic particulates[J]. Journal of Plankton Research, 2002,24:471-479.
[15] DAVID R D, ROBERT A M. Determining the backward scattering coefficient with fixed-angle backscattering sensors-revisited[Z]. Santa Fe New Mexico, Ocean Optics XVI, 2002.
[16] MOREL A, GENTILI B, CLAUSTRE H, et al. Optical properties of the clearest natural waters[J]. Limnology and Oceanography,2007,52(1):217-229.
[17] ROBERT D V, CHRISTOPHER W B. Light backscattering properties of marine phytoplankton: relationships to cell size, chemical composition and taxonomy[J]. Journal of Plankton Reasearch,2004,23:191-212.
[18] MACCALLUM I, CUNNINGHAM A, MCKEE D. The measurement and modeling of light scattering by phytoplankton cells at narrow forward angles[J]. J Opt. A: Pure Appl. Opt, 2004,6:698-702.
[19] ZHOU Wen, WANG Gui-fen, SUN Zhao-hua, et al. Variations in the optical scattering properties of phytoplankton cultures[J]. Optics Express, 2012,20(10):11 189-11 206.
[20] STRAMSKI D, MOREL A, BRICAUD A. Modeling the light attenuation and scattering by spherical phytoplanktonic cells: a retrieval of the bulk refractive index[J]. Applied Optics,1988,27(19):3 954-3 956.
[21] GAIGALAS A K, HE H J, WANG L L. Measurement of absorption and scattering with an integrating sphere detector: application to microalgae[J]. Journal of Research of the National Institute of Standards and Technology,2009,114(2).
[22] WAYNE H S, EMMANUEL S B. Calibrated near-forward volume scattering function obtained from the LISST particle sizer[J]. Optics Express,2005,14(8):3 602-3 615.
[23] MARKUS Z. Electromagnetic Field Theory: A Problem Solving Approach[M]. US: Krieger Publishing Company,2003:78-235.
[24] YENTSCH C S, MENZEL D W. A method for the determination of phytoplankton chlorophyll and pheophytin by fluorescence[J]. Deep Sea Res,1963,10:221-231.
[25] NEVEUX J, LANTOINE F. Spectrofluorometric assay of chlorophylls and pheopigments using least square approximation technique[J]. Deep Sea Res, 1993,40(9):1 747-1 765.
[26] TRUPER H G, YENTSCH C S. Use of glass-fiber filters for the rapid preparation of in vivo absorption spectra of photosynthetic bacteria[J]. J.Bacteriol,1967,94(12):55-56.
[27] TASSAN S, FERRARI G M. An alternative approach to absorption measurements of aquatic particles retained on filters[J]. Limnol Oceanogr,1995a,40(13):58-68.
[28] TASSAN S, FERRARI G M. Proposal for the measurement of backward and total scattering by mineral particles suspended in water[J].Appl.Optics,1995b,34(83):45-53.
[29] HUBERT L, XAVIER M. Investigation of the optical backscattering to scattering ratio of marine particles in relation to their biogeochemical composition in the eastern English Channel and southern North Sea[J]. Limnology Oceanography, 2007,52(2):739-752.
[30] AHN Y H, BRICAUD A, MOREL A. Light backscattering efficiency and related properties of some phytoplankters[J]. Deep Sea Res,1992,39(18):35-55.
[31] AMANDA L W, PEGAU W S, et al. Spectral backscattering properties of marine phytoplankton cultures[J]. Optics Express,2010,18(14):15 073-15 093.