Influence of Effluents from a Zinc Factory on Lichens

Abstract

Lichen species richness and abundance are reduced by approximately 90% in lichen communities near a zinc smelter at Lehigh Water Gap in comparison with the lichen communities of Delaware Water Gap. The principal cause of the impoverished lichen flora in the Lehigh Water Gap area is probably high concentrations of zinc. Of the non—pollution and pollution factors considered, only abnormal soil concentrations of zinc and cadmium extend beyond the limits of the lichen impoverishment zone. Because Zn is present in concentrations generally 100 times higher than that of Cd and because Cd is experimentally shown to be no more toxic to lichens than is Zn, it is probable that Zn is the more important, detrimental factor to lichens in the Palmerton area. Near the smelters, Zn, Cd and sulfur dioxide are all present in sufficiently high concentrations to be detrimental to lichen growth and survival. However, at the perimeter of the lichen—impoverished zone, only Zn is present in high enough concentrations to be phytotoxic. Although microclimatic alteration in forested areas near Palmerton may be sufficiently great to be a stress for a few lichen species that are adapted to shaded conditions, no microclimatic differences were demonstrable between Delaware and Lehigh Water Gaps for open habitats where most lichen species normally occur in this area. Variations in such factors as lichen geographical range, climate, substrate composition and abundance, and fire history are probably of negligible importance in explaining the reduction in lichen numbers or abundance in Lehigh Water Gap.

Plants and Atmospheric Aerosols

“…Within a 0.5 km radius, vegetation was nearly absent. Accumulation of heavy metals was greatest in bryophytes and lichens (Salemaa et al 2004), though many species are relatively insensitive (Nash 1975;Tremper et al 2004;Otnyukova 2007). Due to their high C p , these species serve as useful receptors in biomonitoring surveys (Wolterbeek 2002).…”

Manganese as a site factor for epiphytic lichens

“…Based on correlations between high Mn concentrations and low epiphytic lichen abundance repeatedly found in the field, we conducted a case study of the ecophysiological role of this transition metal in lichens. Our research on effects of Mn on lichens differs principally from previous heavy metal and lichen studies of, e.g., NIEBOER et al (1972), NASH (1975, PUCKETT (1976), BROWN & BECKETT (1983), BECKETT & BROWN (1984a), PURVIS & HALLS 1996, or GARTY et al (1992. This is because the cited studies generally deal with transition metals that either occur in extreme heavy metalrich rock environments or that are found in "normal" ecosystems due to anthropogenic pollution.…”

Lichen biomonitoring near Karabash Smelter Town, Ural Mountains, Russia, one of the most polluted areas in the world

“…The elements S, Cu and Zn, essential biological elements, may reach toxic concentrations in lichens (Nash 1975;Branquinho et al 1999). The absence of Hypogymnia within 16.5 km of Karabash and low variation in S, Cu and Zn (figure 2) contents in native thalli suggest critical level excesses.…”