Atmospheric Measurement Techniques Discussions www.atmos-meas-tech-discuss.net 1867-8610 3 4 2010 10.5194/amtd-3-3851-2010 http://www.atmos-meas-tech-discuss.net/3/3851/2010/ http://www.atmos-meas-tech-discuss.net/3/3851/2010/amtd-3-3851-2010.html http://www.atmos-meas-tech-discuss.net/3/3851/2010/amtd-3-3851-2010.pdf 3851 3876 2010-08-25 Dry deposition of NaCl aerosols: theory and method for a modified leaf-washing technique A. Reinap ausra.reinap@lnu.se B. L. B. Wiman S. Gunnarsson B. Svenningsson Environmental Science & Technology Research Section, School of Natural Sciences, Linnaeus University, Sweden Department of Nuclear Physics, Lund University, Sweden Within the framework of aerosol deposition to vegetation we present a specially designed leaf wash-off method used in a wind-tunnel based study, where leaves of <i>Quercus robur</i> L. were exposed to NaCl aerosols. We summarise the principles and illustrate the method for two types of substances, the chloride ion and the sodium ion, and for two levels of aerosol exposure prior to leaf washing. On the average, in the low-exposure experiments (S1), the 1st (2nd) wash-off step provided 90% (96%) of the amount of Cl^&minus; on the leaves. In the high-exposure experiments (S2) the corresponding values were 96% and 99%. For sodium, the general dynamics resembles that of chloride, but the amounts washed off were, in both series, on the average below what would be expected if the equivalent ratio in the tunnel aerosol were to be preserved. Na⁺ showed adsorption and/or absorption at the leaf surfaces. The difference between the mean values of the amounts of chloride and of sodium washed off in S1 was not statistically significant, the mean Na⁺ to Cl^&minus; difference as a fraction of Cl^&minus; being minus 18%±27%; corresponding values for S2 were minus 16%±9%, however (<i>p</i><0.05). In the latter case, 101±57 μequiv Na⁺ per m² of leaf area were missing for the equivalent relationship 1:1 with Cl^&minus; to be met. Although uncertainties are thus large, this indicates the magnitude of the Na⁺-retention. The method is suitable not only for chloride, an inexpensive and easy-to-handle tracer, but also for sodium under exposure at high aerosol concentrations. Our findings will help design further studies of aerosol/forest interactions. Burkhardt,~J., Koch,~K., and Kaiser,~H.: Deliquescence of deposited atmospheric particles on leaf surfaces, Water Air Soil Poll., 1, 313–321, 2001. Cappelatto,~R. and Peters,~N E.: Dry deposition and canopy leaching rates in deciduous and coniferous forests of the Georgia Piedmont: an assessment of the regression model, J. Hydrol., 169, 131–150, 1995. Chamberlain,~A C.: Transport of Lycopodium spores and other small particles to rough surfaces, P. R. Soc. A, 296, 45–70, 1967. Dambrine,~E., Pollier,~B., Bonneau,~M., and Ignatova,~N.: Use of artificial trees to assess dry deposition in spruce stands, Atmos. Environ., 32(10), 1817–1824, 1998. Draaijers,~G P J., Erisman,~J W., Spranger,~T., and Wyers,~G P.: The application of throughfall measurements for atmospheric deposition monitoring, Atmos. Environ., 30(19), 3349–3361, 1996. Erisman,~J W., Draaijers,~G., Duyzer,~J., Hofschreuder,~P., Van Leeuwen,~N., Römer,~F., Ruijgrok,~W., Wyers,~P., and Gallagher,~M.: Particle deposition to forests-summary of results and applications, Atmos. Environ., 31, 321–331, 1996. Fowler,~D., Pilegaard,~K., Sutton,~M A., Ambus,~P., Raivonen,~M., Duyzer,~J., Simpson,~D., Fagerli,~H., Fuzzi,~S., Schjoerring,~J K., Granier,~C., Neftel,~A., Isaksen,~I S A., Laj,~P., Maione,~M., Monks,~P S., and Burkhardt,~J.: Atmospheric composition change: ecosystems–atmosphere interactions, Atmos. Environ., 43, 5193–5267, doi:10.1016/j.atmosenv.2009.07.068, 2009. Gallagher,~M W., Beswick,~K M., Duyzer,~J., Westrate,~H., Choularton,~T W., and Hummelshoj,~P.: Measurement of aerosol fluxes to Speulder forest using a~micrometeorological technique, Atmos. Environ., 31, 371–385, 1997. Hansen,~B. and Nielsen,~K E.: Comparison of acidic deposition to semi-natural ecosystems in Denmark-coastal health and oak wood, Atmos. Environ., 32, 1075–1086, 1998. Irving,~H. and Williams,~R J P.: Order of stability of metal complexes, Nature, 162, 746–747, 1948. Lindberg,~S E., Lovett,~G M., Richter,~D D., and Johnson,~D W.: Atmospheric deposition and canopy interactions of major ions in a~forest, Science, 231, 141–145, 1986. Lindberg,~S E., Harris,~R C., Hoffman,~W A., Lovett Jr.,~G M., and Turner,~R R.: Atmospheric chemistry, deposition, and canopy interactions, in: Analysis of Biogeochemical Cycling Processes in Walker Branch Watershed, edited by: Johnson,~D W. and Van Hook,~R I., Springer-Verlag, New York, Berlin, 96–163, 1989. Likens,~G E., Bormann,~F H., Pierce,~R S., Eaton,~J S., and Johnson~N M.: Biogeochemistry of a~forested ecosystem, Springer-Verlag, New York, 1977. Lovett,~G M. and Reiners,~W A.: Canopy structure and cloud water deposition in subalpine coniferous forests, Tellus, 38B, 319–327, 1986. Marcos Moreno,~G. and Lancho Gallardo,~J F.: Atmospheric deposition in oligotrophic \textitQuercus pyrenaica forests: implications for forest nutrition, Forest Ecol. Manag., 171, 17–29, 2002. Marschner,~H., Römheld,~V., and Kissel,~M.: Different strategies in higher plants in mobilization and uptake of iron, J. Plant Nutr., 9, 695–713, 1986. Mellor,~D P. and Maley,~L.: Order of stability of metal complexes, Nature, 161, 436–437, 1948. Mäser,~P., Gierth,~M., and Schroeder~J I.: Molecular mechanisms of potassium and sodium in plants, Plant Soil, 247, 43–54, 2002. Neinhuis,~C. and Barthlott,~W.: Seasonal changes of leaf surface contamination in beech, oak, and ginko in relation to leaf micromorphology and wettability, New Phytol., 138, 91–98, 1998. Ould-Dada,~Z.: Dry deposition profile of small particles within a~model spruce canopy, Sci. Total Environ., 286, 83–96, 2002. Ould-Dada,~Z.: Resuspension of small particles from tree surfaces, Atmos. Environ., 35, 3799–3809, 2001. Paskova,~M.: Bewertung ausgewählter Baum- und Straucharten nach ihrem Staubfangvermögen, M. D. Dend Gesell., 79, 141–147, 1989. Petroff,~A., Mailliat,~A., Amielh,~M., and Anselmet,~F.: Aerosol dry deposition on vegetative canopies. Part I: Review of present knowledge, Atmos. Environ., 42(16), 3625–3653, doi:10.1016/j.atmosenv.2007.09.043, 2007. Pryor,~S C. and Barthelmie,~R J.: Liquid and chemical fluxes in precipitation, throughfall, and stemflow: observations from a~deciduous forest and a~red pine plantation in the Midwestern USA, Water Air Soil Poll., 163, 203–227, 2005. Pryor,~S C., Gallagher,~M., Sievering,~H., Larsen,~S E., Barthelmie,~R J., Birsan,~F., Nemitz,~E., Rinne,~J., Kulmala,~M., Grönholm,~T., Taipale, ~R., and Vesala,~T.: A~review of measurement and modelling results of particle atmosphere-surface exchange, Tellus, 60B, 42–75, 2008. Raebild,~A.: Physiological Responses of Spruce (Picea) Genotypes to Simulated Aerial Borne Salt, PhD Thesis, Department of Economics and Natural Resources. Arboretum, The Royal Veterinary and Agricultural University, 1998. Ragsdale,~H L., Lindberg,~S E., Lovett,~G M., and Schaefer,~D A.: Atmospheric deposition and throughfall fluxes of base cations, in: Stachurski,~A. and Zimka,~J R.: Environ. Pollut., 118, 75–87, 2002, edited by: Johnson,~D W. and Lindberg,~S E., Atmospheric Deposition and Forest Nutrient Cycling, Ecological Studies 91, Springer-Verlag, New York, 235–253, 1992. Reinap,~A., Wiman,~B L B., and Svenningsson,~B.: Aerosol capture by oak leaves – an experimental investigation. European Aerosol Conference 2008, Thessaloniki, Abstract T03A058P, 2008. Reinap,~A., Wiman,~B L B., Svenningsson,~B., and Gunnarsson,~S.: Oak leaves as aerosol collectors: relationships with wind velocity and particle size distribution, Trees, 23, 1263–1274, 2009. Rea,~A W., Lindberg,~S E., and Keeler,~G J.: Dry deposition and foliar leaching of mercury and selected trace elements in deciduous forest throughfall, Atmos. Environ., 35, 3453–3462, 2001. Ren,~L Q., Wang,~S J., Tian,~X M., Han,~Z W., Yan,~L N., and Qui,~Z M.: Nonsmooth morphologies of typical plant leaf surfaces and their anti-adhesion effects, J. Bionic Eng., 4, 33–40, 2007. Slinn,~W G N.: Predictions for particle deposition to vegetative surfaces, Atmos. Environ., 16, 1785–1794, 1982. Stachurski,~A. and Zimka,~J R.: Atmospheric deposition and ionic interactions within a~beech canopy in the Karkonosze Mountains, Environ. Pollut., 118, 75–87, 2002. Wuyts,~K., Verheyen,~K., De Schrijver,~A., Cornelis,~W M., and Gabriels,~D.: The impact of forest edge structure on longitudinal patterns of deposition, wind speed, and turbulence, Atmos. Environ., 42, 8651–8660, 2008. Watanabe,~M., Takamatsu,~T., Koshikawa,~M K., Yamamura,~S., and Inubushi,~K.: Dry deposition of acidic air pollutants to tree leaves, determined by a~modified leaf-washing technique, Atmos. Environ., 42, 7339–7347, 2008. Wesely,~M L. and Hicks,~B B.: A~review of the current status of knowledge on dry deposition, Atmos. Environ., 34, 2261–2282, 2000. Wiman,~B L B.: Aerosol collection by Scots pine seedlings: design and application of a~wind tunnel method, Oikos, 36, 83–92, 1981. Wiman,~B L B. and Ågren,~G I.: Aerosol depletion and deposition in forest – a~model analysis, Atmos. Environ., 19, 335–347, 1985.