9/23/2009~~Pyxine cocoes , a foliose lichen, as a bioindicator/biomonitor for aerial pollution was first reported in Iloilo City, Philippines: An Update

Isidro T. Savillo*

    Pyxine cocoes was first reported in 2003 by Savillo, I. in his publication titled “The Common Abundance of Pyxine cocoes (Swartz)Nyl.  in district parks of Iloilo City, Philippines” where he concluded  that “Pyxine cocoes being abundant, may serve as a good bioindicator for atmospheric pollution and further cellular analysis would reveal its actual physiological characteristics.” This finding was presented in a Regional Convention (Region VI) of the Philippine Society for Microbiology and this study was granted a Wildlife Gratuitous Permit  No. 101 of the DENR.  Pyxine cocoes has been reported as a pollution tolerant lichen by the following:  Thrower in 1988 (Hongkong), Nayaka et al in 2003 (India) and Saipunkaew et al in 2004 (Thailand). In 2009, Gruezo  and his team from  U.P Los Banos, U.P. Diliman and  Philippine Nuclear Research Institute had come up with a publication titled “Lichen Pyxine cocoes (Sw.) Nyl. (Physciaceae) as a potential biomonitor for atmospheric pollution in Southern Luzon, Philippines.”  Their study area spanned  four Metro Manila sites and two sites near and around coal fired power plants where they concluded that  the  lichen Pyxine cocoes (Sw.) Nyl. (Physciaceae) as being abundant and ubiquitous in all their six study sites hence they considered it as potential biomonitor for atmospheric pollution after analyzing the samples for several air pollution related elements using xray fluorescence spectrometry.  This finding has supported the first pioneering report of Savillo, I. in 2003 in the Philippines regarding the common abundance of this lichen and its usefulness in determining atmospheric pollution. In  Savillo’s  presentation titled “Lichens in Mangroves”  in the 2009 Society of Wetland Scientists Convention in Madison, Wisconsin , he emphasized that Pyxine cocoes  favorably grow in trees adjacent residential areas or areas frequented by humans.  In fact these are far from sources of industrial pollution and far from the city. There may be an intriguing factor(s) responsible for their growth where there is a need to meticulously analyze this factor(s) as pollutant or not.  Saipunkaew  (2004) in her lichen study  used population density as a surrogate measure for pollution levels due to inadequate pollution data.