Seasonal spectral variation of Zostera noltii and its influence on pigment-based Vegetation Indices

The influence of phenological variations on the reflectance of the intertidal marine angiosperm Zostera noltii was studied using spectroradiometry and pigment analysis. Leaves were sampled each month from March to November and spectral reflectance was measured in the 400-900 nm wavelength range in the laboratory for increasing biomass. High Performance Liquid Chromatography (HPLC) was used to assess the pigment composition and concentration of the leaves and their epiphytes. Several vegetation indices (VIs) were tested for their sensitivity to seasonal variations, from NDVI-like ratios to indices based on derivative analysis. Pigment concentration showed a seasonal effect, with the highest concentrations observed in summer, synchronous with the above-ground biomass peak. The seasonal variations were clearly visible in the leaf reflectance spectrum, showing for the same amount of vegetation, lower reflectance in summer for the visible wavelengths and a higher near-infrared (NIR) plateau compared to the other months. Indices based on the difference between the red and NIR reflectance values, typically all the NDVI-like ratios, were the most sensitive to seasonal variations in pigment concentration. In fact, seasonal effects were systematically reduced for VIs including a blue band correction, namely the modified Specific Ratio (mSR(705)), the modified Normalized Difference (mND(705)), the modified NDVIs for Landsat, FORMOSAT and narrow band NDVI (mNDVI(673)) as well as the Atmospherically Resistant Vegetation Index (ARVI). However, these indices showed a faster saturation for increasing seagrass biomass, except for the mSR(705), which was the least sensitive to biomass saturation. The interesting properties of this index suggest that it should now be tested for airborne or satellite remote sensing mapping of Z. noltii beds but it requires a high spectral resolution and cannot be applied to multispectral satellite images.

[1]  F. Baret,et al.  PROSPECT: A model of leaf optical properties spectra , 1990 .

[2]  R. Zimmerman,et al.  Effects of epiphyte load on optical properties and photosynthetic potential of the seagrasses Thalassia testudinum Banks ex König and Zostera marina L. , 2003 .

[3]  R. C. Phillips,et al.  Differentiation in habitat response among populations of New World seagrass , 1979 .

[4]  Robert J. Orth,et al.  Seagrasses: biology, ecology and conservation , 2006 .

[5]  C. Llewellyn,et al.  The rapid determination of algal chlorophyll and carotenoid pigments and their breakdown products in natural waters by reverse-phase high-performance liquid chromatography , 1983 .

[6]  Gregory A Carter,et al.  Optical properties of intact leaves for estimating chlorophyll concentration. , 2002, Journal of environmental quality.

[7]  J. A. Schell,et al.  Monitoring vegetation systems in the great plains with ERTS , 1973 .

[8]  W. Dennison,et al.  Light intensity and the interactions between physiology, morphology and stable isotope ratios in five species of seagrass , 1996 .

[9]  J. Mercado,et al.  Use of light and inorganic carbon acquisition by two morphotypes of Zostera noltii Hornem , 2003 .

[10]  G. Asner.  Biophysical and Biochemical Sources of Variability in Canopy Reflectance , 1998 .

[11]  F. Niell,et al.  Seasonal dynamics of biomass and nutrient content in the intertidal seagrass Zostera noltii Hornem. from Palmones River estuary, Spain , 1993 .

[12]  S. K. Fyfe,et al.  Hyperspectral studies of New South Wales seagrasses with particular emphasis on the detection of light stress in Eelgrass Zostera capricorni , 2004 .

[13]  S. Fyfe,et al.  Spatial and temporal variation in spectral reflectance: Are seagrass species spectrally distinct? , 2003 .

[14]  I. Auby,et al.  Seasonal variations in photosynthetic irradiance response curves of macrophytes from a Mediterranean coastal lagoon , 2005 .

[15]  Moon S. Kim,et al.  Ratio analysis of reflectance spectra (RARS): An algorithm for the remote estimation of the concentrations of chlorophyll A, chlorophyll B, and carotenoids in soybean leaves , 1992 .

[16]  I. Auby.  Contribution à l'étude des herbiers de Zostera noltii du Bassin d'Arcachon : Dynamique, production et dégradation, macrofaune associée , 1991 .

[17]  Chris Roelfsema,et al.  Mapping seagrass species, cover and biomass in shallow waters : An assessment of satellite multi-spectral and airborne hyper-spectral imaging systems in Moreton Bay (Australia) , 2008 .

[18]  S. W. Jeffrey,et al.  Application of pigment methods to oceanography , 1997 .

[19]  Fuan Tsai,et al.  Derivative Analysis of Hyperspectral Data , 1998 .

[20]  C. Tucker.  Red and photographic infrared linear combinations for monitoring vegetation , 1979 .

[21]  C. Jiménez,et al.  Photosynthetic adaptation of Zostera noltii Hornem. , 1987 .

[22]  M. Robin,et al.  Increase in seagrass distribution at Bourgneuf Bay (France) detected by spatial remote sensing , 2010 .

[23]  D. Sims,et al.  Relationships between leaf pigment content and spectral reflectance across a wide range of species, leaf structures and developmental stages , 2002 .

[24]  I. Auby,et al.  Seasonal dynamics of Zostera noltii hornem. In the bay of arcachon (France) , 1996 .

[25]  G. A. Blackburn,et al.  Quantifying Chlorophylls and Caroteniods at Leaf and Canopy Scales: An Evaluation of Some Hyperspectral Approaches , 1998 .

[26]  W. Dennison,et al.  Physiological and morphological responses of the seagrass Zostera capricorni Aschers, to light intensity , 1994 .

[27]  P. Richard,et al.  Are epiphytes a significant component of intertidal Zostera noltii beds , 2009 .

[28]  S. Enríquez.  Light absorption efficiency and the package effect in the leaves of the seagrass Thalassia testudinum , 2005 .

[29]  P. Mumby,et al.  Measurement of seagrass standing crop using satellite and digital airborne remote sensing , 1997 .

[30]  J. L. Pérez-Lloréns,et al.  Effects of light availability on growth, architecture and nutrient content of the seagrass Zostera noltii Hornem , 2002 .

[31]  J. L. Pérez-Lloréns,et al.  Effects of light and biomass partitioning on growth, photosynthesis and carbohydrate content of the seagrass Zostera noltii Hornem , 2007 .

[32]  M. Dring,et al.  The Biology of Marine Plants , 1991 .

[33]  Veronique Carrere,et al.  Spectrometric constraint in analysis of benthic diatom biomass using monospecific cultures , 2003 .

[34]  Didier Tanré,et al.  Atmospherically resistant vegetation index (ARVI) for EOS-MODIS , 1992, IEEE Trans. Geosci. Remote. Sens..

[35]  H. Asmus,et al.  The importance of grazing food chain for energy flow and production in three intertidal sand bottom communities of the northern Wadden Sea , 1985, Helgoländer Meeresuntersuchungen.

[36]  V. Brotas,et al.  Effect of sediment type on microphytobenthos vertical distribution: Modelling the productive biomass and improving ground truth measurements , 2006 .

[37]  W. Dennison,et al.  Photosynthetic responses of Zostera marina L. (Eelgrass) to in situ manipulations of light intensity , 1982, Oecologia.

[38]  Photophysiological responses of Halophila johnsonii to experimental hyposaline and hyper-CDOM conditions , 2008 .

[39]  David C. Douglas,et al.  Distribution and stability of eelgrass beds at Izembek Lagoon, Alaska , 1997 .

[40]  W. Dennison,et al.  Photoadaptation and growth of Zostera marina L. (eelgrass) transplants along a depth gradient , 1986 .

[41]  Rodney M. Forster,et al.  Relationship of intertidal surface sediment chlorophyll concentration to hyperspectral reflectance and chlorophyll fluorescence , 2006 .

[42]  C. Philippart,et al.  Leaf dynamics and standing stocks of intertidal Zostera noltii Hornem. and Cymodocea nodosa (Ucria) Ascherson on the Banc d'Arguin (Mauritania) , 1993, Hydrobiologia.

[43]  João Silva,et al.  Daily variation patterns in seagrass photosynthesis along a vertical gradient , 2003 .

[44]  Roy A. Armstrong,et al.  Remote sensing of submerged vegetation canopies for biomass estimation , 1993 .

[45]  G. A. Blackburn,et al.  Spectral indices for estimating photosynthetic pigment concentrations: A test using senescent tree leaves , 1998 .

[46]  Rui Santos,et al.  Individual and population plasticity of the seagrass Zostera noltii along a vertical intertidal gradient , 2009 .

[47]  K. Dijkema,et al.  Wax and wane of Zostera noltii Hornem. in the Dutch Wadden Sea. , 1995 .

[48]  G. A. Blackburn,et al.  Hyperspectral remote sensing of plant pigments. , 2006, Journal of experimental botany.

[49]  A. Huete,et al.  Spectral response of the seagrass Zostera noltii with different sediment backgrounds , 2012 .

[50]  L. Barillé,et al.  Comparative analysis of field and laboratory spectral reflectances of benthic diatoms with a modified Gaussian model approach , 2007 .

[51]  W. Dennison.  Effects of light on seagrass photosynthesis, growth and depth distribution , 1987 .

[52]  C. Philippart.  Seasonal variation in growth and biomass of an intertidal Zostera noltii stand in the Dutch wadden sea , 1995 .

[53]  M. J. Durako.  Leaf optical properties and photosynthetic leaf absorptances in several Australian seagrasses , 2007 .

[54]  Geir Johnsen,et al.  Using absorbance and fluorescence spectra to discriminate microalgae , 2002 .

[55]  Frans C. Verhagen,et al.  Seasonal variation in the intertidal seagrass Zostera noltii Hornem.: coupling demographic and physiological patterns , 1996 .

[56]  C. Mcmillan,et al.  Chlorophyll composition under controlled light conditions as related to the distribution of seagrasses in Texas and the U.S. Virgin Islands , 1979 .

[57]  J. L. Pérez-Lloréns,et al.  Morphological and physiological differences between two morphotypes of Zostera noltii Hornem. from the south-western Iberian Peninsula , 2000, Helgoland Marine Research.

[58]  B. Datt.  Remote Sensing of Chlorophyll a, Chlorophyll b, Chlorophyll a+b, and Total Carotenoid Content in Eucalyptus Leaves , 1998 .