ISSN 10674136, Russian Journal of Ecology, 2011, Vol. 42, No. 3, pp. 249–251. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © Sh.R. Abdullin, 2011, published in Ekologiya, 2011, No. 3, pp. 224–226.
Caves are specific ecosystems with the unique
biota. Most caves have a stable environment with the
following distinctive features: a low light intensity,
which decreases to a critical level as the distance from
the entrance increases; slight temperature fluctuations
over the year; and permanently high air humidity
(Hajdu, 1977). Phototrophic ecosystems, with higher
and lower plants as producers, develop at cave
entrances or, in illuminated excursion caves, around
light fixtures (the socalled lampenflora; Mazina and
The purpose of this study was to analyze illumina
tiondependent changes in the composition of pho
totrophic biota in the entrance part of the Shul’gan
Tash (Kapova) Cave. This is a karst cave in limestones
on the right bank of the Belaya River, near the
Shul’gan River mouth (the Southern Urals), on the
territory of the Shul’ganTash Nature Reserve, Bash
kortostan. The cave contains underground lakes,
streams, and a river. Its asymmetrical entrance is 40 m
wide and 13.5 m high (Lyakhnitskii, 2002).
The material for analysis included 17 scrapings and
six geobotanical descriptions of communities on the
left wall in the entrance part of the cave. Sampling,
identification of cyanobacteria and algae, and descrip
tion of communities were performed by standard
methods (Kuzyakhmetov and Dubovik, 2001; Mirkin
et al., 2000). Measurements of illumination were
made at every sampling point.
Four zones were distinguished along the illumina
tion gradient on the left cave wall: (1) 50–40 m from
the entrance (average illumination level below 54 lx),
where the phototrophic biota was represented by
cyanobacteria and algae; (2) 40–30 m from the
entrance (54–127 lx), where the previous groups were
supplemented by mosses; (3) 30–20 m from the
entrance, where ferns appeared; and (4) 20 m or less
from the entrance, where flowering plants appeared.
The results of analysis provided evidence for suc
cession of phototrophic taxa depending on illumina
tion level, which could be termed “illumination zon
The phototrophic biota consists of no more
than six species and infraspecific taxa of cyanobacteria
and algae; i.e., its taxonomic diversity is low. Only in
this zone does the group of dominants include the alga
(Skuja) Kalina et Pun.
The number of cyanobacterial and algal
taxa increases, with the former group gaining domi
nance. Shadetolerant mosses appear, such as
(Garov.) Wijk. et Margad. and
(Schrad.) T.J. Kop.
The number of cyanobacterial and algal spe
cies decreases in favor of diatoms. The moss
Schwagr. (a relatively photophilic species) and
(L.) Bernh. appear.
The phototrophic biota is supplemented
with flowering petrophytes, such as
L., and photophilic
Hessl. The taxonomic diversity
of cyanobacteria and algae remains high, as in zone 3,
with the abundance of diatoms also being high.
Thus, the greatest number of phototrophic species
is characteristic of zone 2, which is the ecotone
between communities formed in the dark deep zone
and in the lighter entrance zone of the cave. In all
zones except the first, the phototrophic biota includes
diagnostic species of the community
described in the
Shul’ganTash Cave previously (Abdullin, 2009). This
is evidence that the ecological distribution range of
cyanobacteria and algae is wider than that of higher
Other authors (e.g., Round, 1981) described a simi
lar pattern of species depletion with decreasing illumi
nation in the entrance parts of caves: angiosperms—
ferns—mosses—algae and cyanobacteria. Measure
ments of illumination intensity in different caves made
it possible to determine its limiting values for different
groups of organisms (Johnson, 1979): 10–50 lx for algae
and cyanobacteria, 50–180 lx for mosses, and 250 lx for
ferns. These values agree with our data.
Effect of Illumination on the Distribution of Phototrophic Organisms
in the Entrance Part of the Shul’ganTash Cave
Sh. R. Abdullin
Bashkir State University, ul. Validi 32, Ufa, Republic of Bashkortostan, 450074 Russia; email: email@example.com
Received December 28, 2009
: Shul’ganTash Cave, illumination, phototrophic organisms, illumination zoning.