The application of element mapping in the scanning electron microscope
with electron probe microanalysis across the lichen-rock interface is
described with reference to Trapelia involuta growing on a granite su
bstratum. The preparation of samples containing both organic and miner
al components required the development of specialized techniques to ma
intain both chemical and structural integrity at the 2 mu m resolution
of the X-ray element maps. X-ray element maps show the distribution o
f entrained rock particles at the lichen-rock interface and chemical l
ocalization which is strongly related to anatomical structure for the
essential elements S, Fe, Ca, Na, It and P. The ability to map element
distribution across the lichen-rock interface has wide-ranging potent
ial applications in studies such as the biodeterioration of buildings
and monuments and the mobilization and uptake of toxic elements from c
ontaminated substrata.