Spatial variation of ecophysiological parameters in the lichen Pseudevernia furfuracea transplanted in an area surrounding a cement plant (S Italy)

Thalli of the lichen Pseudevernia furfuraceawere transplanted for 3 months (November 2010–January2011) at 61 monitoring sites around a cement plantnear Castrovillari (Calabria, southern Italy). NH3, NOxand SO2 concentrations were monitored monthly in asubarea of 10 sites (SA10) where the cement plant waslocated. At the end of the exposure period, the integrityof cell membranes; membrane lipid peroxidation (thiobarbituricacid reactive substances, TBARS level); vitality(cell respiration); chlorophyll a; chlorophyll b;carotenoids; phaeophytization quotient; photosyntheticefficiency and thalli concentrations of Al, Ca, Mg, VandFe were measured. NOx concentrations correlated withthe site distance from the cement plant while NH3concentrations correlated with lichen vitality withinSA10. For the monitoring area as a whole, only Fe andMg concentrations correlated with membrane lipid peroxidation,while TBARS levels showed a significantincrease and chlorophyll a, chlorophyll b and carotenoidsa significant decrease with respect to the lichenorigin area. Multivariate analysis (detrended correspondenceanalysis, cluster analysis and multi-response permutationprocedure) of the eco-physiologicalparameters × monitoring sites data set resulted in fourclusters termed C1, C2, C3 and C4. The ecophysiologicalparameters were compared among thefour clusters and lichen origin area by one-wayANOVA. An index of environmental favourableness(IEF) to lichens was calculated to evaluate the spatialrecovery of impaired values of TBARS, chlorophyll a,chlorophyll b, xanthophylls + carotenoids andphaeophytization quotient. The results indicate thatthere is no clear spatial trend in mycobiont impairmenteven though the IEF values suggest a higher number ofsites with low levels of membrane lipid peroxidation inthe 2-–3-km distance band from the cement plant (theoutermost) than in the two other distance bands (0–1 and1–2 km). The photobiont seems to be damaged mainlyin the inner distance band of the study area as suggestedby the gradual but significant recovery trend of pigmentlevels and phaeophytization quotient from the innerdistance band to the outer one (as shown by the IEFvalues). Conversion of chlorophyll to phaeophytin probablyis not the only process affecting pigment levels.