The effect of the substrate on the growth and reproduction of the lichens Cladonia rangiferina and C. mitis

The growth rate and percentage of fertile individuals were studied in the lichens Cladonia rangiferina and C. mitis growing on various substrates in a heath-lichen pine forest and a bilberry-cowberry pine forest with Pleurozium and other mosses, both on the White Sea coast. The substrates were soil, rocks, and pine wood. The proportion of different forms of C. rangiferina growing on the same substrate was compared between the two forest types. C. rangiferina f. rangiferina was more abundant on soil, while C. rangiferina f. crispata dominated on wood. The effect of the substrate on the development of different lichen forms is discussed. The maximum growth rate and the maximum percentage of fertile individuals were recorded in the lichens growing on soil; these parameters were minimal in the lichens growing on wood. These differences were more pronounced in C. rangiferina than in C. mitis. The effects of the nutritive quality and the humidity of the substrate on the growth rate and apothecia formation in lichens are discussed.