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Microphotometry of Underwater Shadowing by a Moss from a Niagara Escarpment Waterfall

Published online by Cambridge University Press:  19 November 2010

Howard J. Swatland*
Affiliation:
University of Guelph, Guelph, Ontario N1G2W1, Canada
*
Corresponding author. E-mail: [email protected]
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Abstract

Microscope and fiber-optic spectrophotometry of transmittance and backscattering both showed moss leaves to be capable of casting strong shadows, with a single leaf blocking approximately 90% of incident light from a point source. In leaves with only one layer of cells, the transmittance through the cytoplasm of single cells was similar to that for whole leaves. Analysis of cell wall birefringence by polarized-light interferometry indicated that cell walls might normally scatter rather than transmit light. Spectra transmitted through, or backscattered from, the upper green layers of moss were dominated by selective absorbance from chlorophyll, but there was also evidence of wavelength-dependent scattering, as detected in the lower layers of brown, dead moss. Specular reflectance from moss leaves was detected by polarimetry and may have contributed to the relatively high macroscopic transmittance of stationary moss in water. Shadowing by moss leaves was confirmed by dynamic measurements of mosses in turbulent water without bubbles. Flicker patterns from leaves were superimposed on the underwater flicker pattern created at the air-water interface, thus flecks of light were reduced in intensity, increased in frequency, and decreased in duration. This was detected with both point source and diffuse illumination of samples.

Type
Biological Applications
Copyright
Copyright © Microscopy Society of America 2011

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References

REFERENCES

Bennett, H.S. (1950). The microscopical investigation of biological materials with polarized light. In McClung's Handbook of Microscopical Technique, 3rd ed., McClung-Jones, R. (Ed.), p. 637. New York: Hoeber.Google Scholar
Brodersen, C.R. & Vogelmann, T.C. (2007). Do epidermal lens cells facilitate the absorptance of diffuse light? Am J Botany 94, 10611066.CrossRefGoogle ScholarPubMed
Chen, J., Zhang, D.D., Wang, S., Xiao, T. & Huang, R. (2004). Factors controlling tufa deposition in natural waters at waterfall sites. Sediment Geol 166, 353366.Google Scholar
Conard, H.S. & Redfearn, P.L. (1979). How to Know the Mosses and Liverworts. Dubuque, IA: Brown.Google Scholar
Cummings, M. & Johnsen, S. (2007). Light, effects of. In Encyclopedia of Tidepools and Rocky Shores, Denny, M. & Gaines, S. (Eds.), pp. 327331. Berkeley, CA: University of California Press.Google Scholar
Emig, W.H. (1917). Mosses as rock builders. Oklahoma Acad Sci 1, 3840.Google Scholar
Eze, J.M.O. & Berrie, G.K. (1977). Further investigations into the physiological relationship between an epiphyllous liverwort and its host leaves. Ann Bot 41, 351358.CrossRefGoogle Scholar
Flohn, H. (1969). Climate and Weather. New York: McGraw-Hill.Google Scholar
Glime, J.M. (2007). Bryophyte Ecology. Vol. 1. Physiological Ecology. Ebook sponsored by Michigan Technological University and the International Association of Bryologists. Accessed April 7, 2010 at www.bryoecol.mtu.edu.Google Scholar
Harris, A. (2008). Spectral reflectance and photosynthetic properties of Sphagnum mosses exposed to progressive drought. Ecohydrology 1, 3542.CrossRefGoogle Scholar
Hauer, F.R. & Hill, W.R. (2006). Temperature, light, and oxygen. In Methods in Stream Ecology, Hauer, F.R. & Lamberti, G.A. (Eds.), pp. 103117. Burlington, MA: Elsevier–Academic Press.Google Scholar
Haupt, W. (1982). Light-mediated movement of chloroplasts. Ann Rev Plant Physiol 33, 205233.CrossRefGoogle Scholar
Hooke, R. (1665). Micrographia or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries Thereupon, pp. 131135. London: Royal Society; reprinted by Dover Publications, New York, 1961.Google Scholar
Kaniewska, P., Kenneth, A. & Hoegh-Guldberg, O. (2008). Variation in colony geometry modulates internal light levels in branching corals, Acropora humilis and Stylophora pistillata. Mar Biol 155, 649660.CrossRefGoogle Scholar
Können, G.P. (1985). Polarized Light in Nature. Cambridge, UK: Cambridge University Press.Google Scholar
Merz-Preiss, M. & Riding, R. (1999). Cyanobacterial tufa calcification in two freshwater streams: Ambient environment, chemical thresholds and biological processes. Sediment Geol 126, 103124.CrossRefGoogle Scholar
Nakamura, T. & Yamasaki, H. (2008). Flicker light effects on photosynthesis of symbiotic algae in the reef-building coral Acropora digitifera (Cnidaria: Anthozoa: Scleractinia). Pacific Sci 62, 341350.CrossRefGoogle Scholar
Pentecost, A. (2005). Travertine. Berlin: Springer-Verlag.Google Scholar
Pentecost, A. & Coletta, P. (2007). The role of photosynthesis and CO2 evasion in travertine formation; a quantitative investigation at an important travertine-depositing hot spring, Le Zitelle, Lazio, Italy. J Geol Soc Lond 164, 843853.Google Scholar
Rice, S.K., Collins, D. & Anderson, A.M. (2001). Functional significance of variation in bryophyte canopy structure. Am J Botany 88, 15681576.Google Scholar
Rice, S.K., Gutman, C. & Krouglicof, N. (2005). Laser scanning reveals bryophyte canopy structure. New Phytol 166, 695704.Google Scholar
Rogerson, M., Pedley, H.M., Wadhawan, J.D. & Middleton, R. (2008). New insights into biological influence on the geochemistry of freshwater carbonate deposits. Geochim Cosmochim Acta 72, 49764987.CrossRefGoogle Scholar
Steel, R.G.D. & Torrie, J.H. (1980). Principles and Procedures of Statistics. A Biometrical Approach, 2nd ed., pp. 6783. New York: McGraw-Hill.Google Scholar
Swatland, H.J. (1991). Analysis of signals from a UV fluorescence probe for connective tissue in beef carcasses. Comput Electron Agric 6, 225234.Google Scholar
Swatland, H.J. (1998). Computer Operation for Microscope Photometry. Boca Raton, FL: CRC Press.Google Scholar
Swatland, H.J. (2010). Polarized-light interferometry of calcium carbonate deposition in moss from a waterfall on the Niagara Escarpment. Microsc Microanal 16, 306312.CrossRefGoogle ScholarPubMed
Thomas, P.A. & Packham, R.C. (2007). Ecology of Woodlands and Forests. Cambridge, UK: Cambridge University Press.CrossRefGoogle Scholar
Vogelmann, T.C. (1993). Plant tissue optics. Annu Rev Plant Physiol Plant Mol Biol 44, 231251.CrossRefGoogle Scholar
Waite, R. & Sack, L. (2010). How does moss photosynthesis relate to leaf and canopy structure? Trait relationships for 10 Hawaiian species of contrasting light habitats. New Phytol 185, 156172.CrossRefGoogle ScholarPubMed
Zotz, G. & Kahler, H. (2007). A moss “canopy”—Small-scale differences in microclimate and physiological traits in Tortula ruralis. Flora 202, 661666.CrossRefGoogle Scholar