THE EFFECT OF SIMULATED ACID-RAIN ON SURFACE-MORPHOLOGY AND N-ALKANE COMPOSITION OF PSEUDEVERNIA-FURFURACEA

The effects of simulated sulphuric acid rain were investigated, under controlled laboratory conditions, on the surface structure and n-alkan e composition of the lichen Pseudevernia furfuracea. Thalli were colle cted from Larix decidua bark in a wood in a Piedmont alpine valley and treated with three concentrations of H2SO4. The response to simulated acid rain was a clear change in the quantitative alkane composition, with a decreasing trend observed for C-28 and C-30 with increasing sul phuric acid concentration. From a morphological point of view, a progr essive reduction of the surface amorphous layer was observed as a cons equence of the exposure of thalli to the acid rain treatments. (C) 199 7 The British Lichen Society.