ISSN 10674136, Russian Journal of Ecology, 2010, Vol. 41, No. 3, pp. 211–217. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © M.S. Buldakov, 2010, published in Ekologiya, 2010, No. 3, pp. 173–179.
Epiphytic lichens are sensitive to pollutants, which
accounts for their long and wide use as indicators in air
pollution biomonitoring (Skye, 1968; Byazrov, 2002;
etc.). However, to adequately estimate anthropogenic
load from the state of epiphytic lichen populations, it
is necessary to know the causes and limits of natural
variation in their viability and reproductive process.
Unfortunately, the available literature provides little
data on factors accounting for natural variation in the
viability of epiphytic lichen diaspores.
Thus, the viability of
at the initial stages of germination under laboratory
conditions was found to increase at higher air humid
ity (Margot, 1973). Schuster et al. (1985) subsequently
noted that the combination of high humidity and tem
peratures had a deleterious effect on germinating sore
dia of this lichen. Studies performed in North Seattle
(Armstrong, 1990) and piedmont regions of Central
Europe showed that
more successfully in cracks, on rough tree bark, and
amid other epiphytes. However, Ott (1987) revealed
no differences in this respect between rough and
smooth bark, attributing this to high humidity (suffi
cient for lichens) provided by oceanic climate on
Dutch islands, where her research was performed.
However, the effect of specific conditions in habitats of
maternal thalli on the development of daughter sore
dia has not been considered in the above studies.
Fiechter and Honegger (1988) observed that the
germination rate of
soredia on ash and
spruce trees in the vicinity of Zurich, Switzerland,
reached a peak in spring and decreased to a minimum
in summer and early autumn. However, weather
parameters in the period of their study sharply differed
from longterm average values, and the data were not
processed statistically. Hence, the authors themselves
noted that the significance of the observed seasonal
trends should be considered with caution.
Thus, to estimate variation in the germination rate
of epiphytic lichen soredia and gain an insight into its
causes, we set ourselves the task to analyze, under lab
oratory conditions, how the viability of soredia in the
depends on the external
and internal factors related to the origin of maternal
thalli. Among the variety of possible relevant factors,
we distinguished those most likely to have an effect on
the development of soredia: immanent properties of
maternal thalli, their growth substrate, micro and
macroclimate, and their seasonal trends.
MATERIAL AND METHODS
The material was collected in slightly disturbed
dark conifer forests in the vicinities of the cities of Gla
zov (the central Vyatka–Kama interfluve, VKI), Vot
kinsk (the southern VKI), Ivdel’ (the central Middle
Urals), and Nyazepetrovsk (the southern Middle
Urals). In each region, two types of forest areas were
distinguished with regard to topographic position and
the type of soil moistening (Vorob’ev, 1953; Kolesni
kov et al., 1974;
, 1972; Rysin and Savel’eva,
(1) mesic to moist forests in upland (plakor) areas
(below, referred to as mesic forests); in particular,
birch–fir forest and wood sorrel–fern fir–spruce for
est (Bisert’), wood sorrel spruce forest, and green moss
spruce forest (Glazov);
Intraspecific Variation in the Viability of Soredia
(L.) Nyl. (Ascomycota: Lecanorales)
M. S. Buldakov
Institute of Plant and Animal Ecology, Ural Division, Russian Academy of Sciences,
ul. Vos’mogo Marta 202, Yekaterinburg, 620144 Russia
Received October 8, 2008
—The contribution of morphological features of parent thalli, substrate and climatic factors, and
their seasonal fluctuations to variation in the viability of vegetative diaspores has been studied on the model
of epiphytic lichen
Seasonal trends in viability have been revealed only in certain types
of biotopes. Hygrothermal conditions and substrate properties in the biotope have proved to have a significant
effect on the viability of soredia.
, viability, growth form, substrate, microclimate, seasons.