Sains Malaysiana 43(3)(2014): 369–375

Trends in Sulfate Dry Deposition over Mixed Dipterocarp Forest in Thailand using

Relaxed Eddy Accumulation Method

(Corak Pemendapan Kering Sulfat di atas Hutan Dipterokarpa Campuran di Thailand menggunakan Kaedah Akumulasi Eddy Santai)

KAN KHOOMSAB¹*, POJANIE KHUMMONGKOL¹& KAZUHIDE MATSUDA²

¹Division of Environmental Technology, School of Energy, Environment and Materials

King Mongkut's University of Technology Thonburi, 126 PrachaUthit Road, Bang Mod, Thungkhru, Bangkok 10140 Thailand

²Faculty of Agriculture Field Science Center, Tokyo University of Agriculture and

Technology 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509 Japan

Diserahkan: 9 Oktober 2012/Diterima: 8 Jun 2013

ABSTRACT

The relaxed eddy accumulation method (REA) was applied for direct measurement of sulfate fluxes over mixed dipterocarp forest. The sampling system using a four-stage filter pack was designed to take updraft or downdraft air samples in the direction of the vertical wind velocity. The deadband of the velocity profile was set at ±0.5 σw in which an air sample with velocity within the set value is rejected. The forest site was located at a latitude of 13o 35' 13.3''N and longitude of 99o 30' 3.9''E Ratchaburi province in Thailand. The sampling period was set in 4 time intervals: 6-12, 12-18, 18-24 and 24-6 h for 3 consecutive days/month (n=144) throughout one year. All the micrometeorological parameters for flux estimation were measured in real time. The concentration and flux of sulfate were found to reach a peak value of 1.32 μg m^-3 and 8.35 μg m^-2 h^-1, respectively, at noon time which indicated the effect of atmospheric instability caused by a high heat transfer during the day. The one-year average deposition velocity was observed to be 0.24 cm s^-1. The coefficient β obtained under high ambient temperature and a humid environment in this tropical climate was 0.49. It has also been observed that βis relatively insensitive to atmospheric stability.

Keywords: Dry deposition; forest; sulfate

ABSTRAK

Kaedah akumulasi eddy santai (REA) telah digunakan untuk pengukuran langsung fluks sulfat di atas hutan dipterokarpa campuran. Sistem pensampelan dengan menggunakan satu pek penapis empat peringkat telah direka untuk mengambil sampel udara draf atas atau bawah yang bergerak dalam arah halaju angin menegak. Paras akhir bagi profil halaju ditetapkan pada ±0.5 σw dan sampel udara dengan halaju di bawah nilai yang ditetapkan adalah ditolak. Tapak hutan tersebut terletak di kedudukan latitud 13o 35' 13.3''N dan longitud 99o 30' 3.9'' E di wilayah Ratchaburi, Thailand. Tempoh persampelan telah dijalankan dalam 4 selang masa: 6-12, 12-18 , 18-24 dan 24-6 jam dalam 3 hari berturut-turut /bulan (n=144) dalam tempoh masa satu tahun. Semua parameter meteorologi mikro untuk anggaran fluks diukur dalam masa sebenar. Sulfat didapati mencapai paras puncak pada kepekatan dan fluks 1.32 μg m^-3 dan 8.35 μg m^-2 jam^-1 masing-masing pada waktu tengahari yang menunjukkan kesan ketidakstabilan atmosfera disebabkan perpindahan haba yang tinggi pada waktu siang. Purata satu tahun kelajuan pemendapan didapati adalah 0.24 cm s^-1. Koefisien β yang diperoleh dalam keadaan suhu ambien yang tinggi dan humiditi dalam iklim tropika adalah 0.49. Hasil kajian juga mendapati βis secara relatif tidak sensitif terhadap kestabilan atmosfera.

Keywords: Hutan; pemendapan kering; sulfat

RUJUKAN

Acid Deposition Monitoring Network in East Asia. 2000. Quality Assurance/Quality Control (QA/QC) Program for Monitoring on Inland Aquatic Environment in East Asia. Report The Second Interim Scientific Advisory Group Meeting of Acid Deposition Monitoring Network in East Asia.

Atkins, D.H.F. & Garland, J.A. 1974. The measurement of deposition velocities for SO₂ and particulate material by gradient method. WMO special environment report No.3, Observation and Measurement of Atmospheric Pollutions. WMO 368 Geneva. 579-594.

Businger, J.A. & Oncley, S.P. 1990. Flux measurement with conditional sampling, J. Atmos. Oceanic. Tech. 7: 349–352.

Desjardins, R.L. 1972. A study of carbon – dioxide and sensible heat fluxes using the eddy correlation technique. PhD. dissertation. Cornell University. USA (unpublished).

Doran, J.C. & Droppo, J.G. 1983. Profiles of elements in the surface boundary layer. In Precipitation Scavenging Dry Deposition and Resuspension, edited by Pruppacher, H.R., Semonin, R.G. & Slinn, W.G.N. l 2: 1003-1012.

Driscoll, C.T., Driscoll, K.M., Mitchell, M.J. & Raynal, D.J. 2003. Effects of acidic deposition on forest and aquatic ecosystems in New York State. Environmental Pollution 123: 327-336.

Duyzer, J., Weststrate, H., Beswick, K. & Gallagher, M.W. 1994. Measurements of the dry deposition flux of sulphate and nitrate aerosols to the speulderbos using micrometeorological methods. Report No.MW-R94/255. Energieonderzoek Centrum Nederland (ECN).

Everett, R.G., Hicks, B.B., Berg, W.W. & Winchester, J.W. 1979. An analysis of particulate sulphur and lead gradient data collected at Argonne Nation Laboratory. Atmospheric Environment 13: 931-934.

Fotiadi, A.K., Lohou, F., Druilhet, A., Serc, D.A., Said, F., Laville, P. & Brut, A. 2005. Methodological development of the conditional sampling method. Part II: Quality control criteria of relaxed eddy accumulation flux measurements. Boundary-Layer Meteorology 117: 577-603.

Gaman, A., Rannik, Ü., Aalto, P., Pohja, T., Siivola, E., Kulmala, M. & Vesala, T. 2004. Relaxed eddy accumulation system for size-resolved aerosol particle flux measurements. J. Atmos. Ocean. Tech. 21: 933-943.

Graus, M., Hansel, A., Wisthaler, A., Lindinger, C., Forkel, R., Hauff, K., Klauer, M., Pfichner, A., RappenglÜck, B., Steigner, D. & Steinbrecher, R. 2006. A relaxed-eddy-accumulation method for the measurement of isoprenoid canopy-fluxes using an online gas-chromatographic technique and PTR-MS simultaneously. Atmospheric Environment 40: 43-54.

GrÖnholm, T., Pasip, A., Veijo, H., Ullarr, R., Janne, R., Lauri, L., Saara, H., Timo, V. & Markku, K. 2007. Measurements of aerosol particle dry deposition velocity using the relaxed eddy accumulation technique. Tellus 59B: 381-386.

GrÖnholm, T., Haapanala, S., Launiainen, S., Rinne, J., Vesala, T. & Rannik, Ü. 2008. The dependence of the β coefficient of REA system with dynamic deadband on atmospheric conditions. Environmental Pollution 152: 597-603.

Haapanala, S., Rinne, J., Pystynen, K-H., Hell´en, H. & Hakola, H. 2005. Measurements of hydrocarbon emissions from a boreal fen using the REA technique. Biogeosciences Discussions 2: 1645-1664.

            Hamotani, K., Yohei, U., Nobutaka, M. & Akira, M. 1996. A system of the relaxed eddy accumulation method to evaluate CO₂ flux over plant canopies. J. Agric. Meteorol. 52(2): 135-139.

Hazi, Y., Heikkinen, M.S.A. & Cohen, B.S. 2003. Size distribution of acidic sulfate ions in fine ambient particulate matter and assessment of source region effect. Atmospheric Environment 37: 5403-5413.

Held, A., Edward, P., Luciana, R., Jim, S., Andrew, T. & Alex, G. 2008. Relaxed eddy accumulation simulations of aerosol number fluxes and potential proxy scalars. Boundary – Layer Meteorol. 129: 451-468.

Hicks, B.B., Wesely, M.L., Durham, J.L. & Brown, M.A. 1982. Some direct measurements of atmospheric sulfur fluxes over a pine plantation. Atmospheric Environment 16: 2899-2903.

Hicks, B.B. & McMillen, R.T. 1984. A simulation of the eddy accumulation method for measuring pollutant fluxes. J. Climate Appl. Meteorol. 23: 637-643.

Hicks, B.B., Matt, D.R., McMillen, R.T., Womack, J.D., Wesely, M.L., Hart, R.L., Cook, D.R. Lindberg, S.E., De Pena, R.G. & Thomson, D.W. 1989. A field investigation of sulfate fluxes to a deciduous forest. Journal of Geophysical Research 94(D10): 13003-13011.

Katul, G., Finkelstein, P.L., Clark, J.F. & Ellestad, T.G. 1996. An investigation of the conditional sampling methods used to estimate fluxes of active, reactive, and passive scalars. J. Appl.Meteor. 35: 1835-1845.

Khoomsab, K. & Pojanie, K. 2010. Monitoring of sulfate and nitrate fluxes above tropical forest using aerodynamic gradient method. International Conference on Environment 2010 (ICENV 2010), Malaysia.

Lamaud, E., Chapus, A., Fontan, J. & Serie, E. 1994. Measurements and parameterization of aerosol dry deposition in semi – arid area. Atmospheric Environment 28: 2461-2471.

Lee, A., Schade, G.W., Holzinger, R. & Goldstein, A.H. 2005. A comparison of new measurements of total monoterpene flux with improved measurements of speciated monoterpene flux. Atmos. Chem. Phys. 5: 505-513.

Lindroos, A.J., Derome, J., Derome, K. & Lindgren, M. 2006. Trends in sulphate deposition on the forests and forest floor and defoliation degree in 16 intensively studied forest stands in Finland during 1996–2003. Boreal. Env. Res. 11: 451-461.

Matsuda, K., Yoshifumi, F., Kentaro, H., Akira, T. & Ko, N. 2010. Deposition velocity of PM2.5 in the summer above a deciduous forest in central Japan. Atmospheric Environment 44: 4582-4587.

Meyer, T.P., Luke, W.T. & Meisinger, J.J. 2006. Fluxes of ammonia and sulfate over maize using relaxed eddy accumulation. Agricultural and Forest Meteorology 136: 203-213.

Myles, L.T., Tilden, P.M. & Larry, R. 2007. Relaxed eddy accumulation measurements of ammonia, nitric acid, sulfur dioxide and particulate sulfate dry deposition near Tampa, FL, USA. Environ. Res. Lett. 2: 1-8.

Monteith, J.L. & Mike, H.U. 2008. Principle of Environmental Physics. USA: Elsevier Inc.

Mortimer, T. 2009. Acid Rain: The Effects. Report Senior Project Social Sciences Department, College of Liberal Arts California Polytechnic State University. USA.

Nemitz, E., Sutton, M.A., Wyers, G.P., Otjes, R.P., Schjoerring, J.K., Gallagher, M.W., Parrington, J., Fowler, D. & Choularton, T.W. 2000. Surface/atmosphere exchange and chemical interaction of gases and aerosols over oilseed rape. Agric. Forest. Meteorol. 105: 427-445.

Odabasi, M. & Bagiroz, H.O. 2002. Sulfate dry deposition fluxes and overall deposition velocities measured with a surrogate surface. Sci. Total. Environ. 297(1-3): 193-201.

Olofsson, M., Ek-Olausson, B., Jensen, N.O., Langer, S. & LjungstrÖm, E. 2005. The flux of isoprene from a willow plantation and the effect on local air quality. Atmospheric Environment 39: 2061-2070.

Pryor, S.C., Larsen, S.E., Sorensen, L.L. & Barthelmie, R.J. 2008. Particle fluxes above forest: Observations, methodological considerations and method comparisons. Environmental Pollution 152: 667-678.

Ren, X., Sanders, J.E., Rajendran, A., Weber, R.J., Goldstein, A.H., Pusede, S.E., Browne, E.C., Min, K.E. & Cohen, R.C. 2011. A relaxed eddy accumulation system for measuring vertical fluxes of nitrous acid. Atmos. Meas. Tech. Discuss. 4: 4105-4130.

Seinfeld, J.H. & Pandis, S.N. 2006. Atmospheric Chemistry and Physics: From Air Pollution to Climate Change. 2nd ed. New York: John Wiley.

Skov, H., Brooks, S.B., Goodsitea, M.E., Lindbergb, S.E., Meyers, T.P., Landis, M.S., Larson, M.R.B., Jensen, B., McConvillee, G. & Christensen, J. 2006. Fluxes of reactive gaseous mercury measured with a newly developed method using relaxed eddy accumulation. Atmospheric Environment 40: 5452-5463.

Tasdemir, Y. & Gunez, H. 2006. Ambient concentration, dry deposition flux and overall deposition velocities of particulate sulfate measured at two sites. Atmospheric Research 81: 250-264.

Wesely, M.L., Cook, R., Hart, R.L. & Speer, R.E. 1985. Measurements and parameterizations of particulate sulfur dry deposition over grass. J. Geophys. Res. 90: 2131-2143.

Wyers, G. & Duyzer, J. 1997. Micrometeorological measurement of dry deposition flux of sulfate and nitrate aerosols to coniferous forest. Atmospheric Environment 31: 333-343.

Zemmelink, H.J., Gieskes, W.W.C., Klaassen, W., de Baar, H.W.J., Dacey, J.W.H., Hintsa, E.J. & McGillis, W.R. 2002. Simultaneous use of relaxed eddy accumulation and gradient flux techniques for the measurement of sea-to-air exchange of dimethyl sulfide. Atmospheric Environment 36: 5709-5717.

*Pengarang untuk surat-menyurat; email: topkan13@hotmail.com