ISSN 1067-4136, Russian Journal of Ecology, 2006, Vol. 37, No. 3, pp. 213–216. © Pleiades Publishing, Inc., 2006.
Original Russian Text © L.A. Gaisina, 2006, published in Ekologiya, 2006, No. 3, pp. 236–240.
The study of algal ecology is one of the most impor-
tant directions in soil algology. However, the attention
of researchers is focused mostly on green (Chloro-
phyta) and blue-green (Cyanophyta) algae that domi-
nate in soil algocenoses. Yellow-green (Xanthophyta)
algae, typical representatives of edaphophytic cenoses,
are often beyond the scope of attention of phycologists.
(Klebs) Silva [syn-
(Klebs) Pasch. and
Klebs] are widespread in the zone extending from
the tundra (Dorogostaiskaya, 1959) to sierozems
(Osmanova, 1968) and alpine deserts (Bazova, 1978).
proved to dominate in the alpine
and subalpine belts of the Eastern Pamir and was typi-
cal for the nival belt.
was found in the
Pamir in all three altitudinal belts in alpine desert,
desert–steppe, and primitive soils, where the tempera-
ture on the soil surface reached 50–54
C in July and
August (Bazova, 1978).
occurred in heavy and slightly
salinized soils in the Southern Turan province of the
Kyzyl Kum Desert, where July temperature averaged
C (Novichkova-Ivanova, 1980).
was found in a grass–wormwood community at an ele-
vation of 800–1800 m a.s.l. on dark stony sierozem in
northern Tajikistan (Mel’nikova, 1975). This species
was also recorded in the algoﬂora of rice ﬁelds on the
above-ﬂoodplain terrace on the left bank of the
Chirchik River, where the maximum annual tempera-
ture reached 41–43
C (Kuchkarova and Pokrovskaya,
is widespread in Antarctica
(Ettl and Gärtner, 1995; Broady et al., 1997). The spe-
sp. nov. (=
Ettl & Gärtner nov. comb. withstood freezing at –20
for one year when it was shipped from the Antarctica to
the United Kingdom.
Thus, the wide geographic distribution of
indicates that this species is tolerant of temperature
ﬂuctuations. However, the tolerance of this alga for
extreme temperatures has not been studied.
The purpose of this study was to analyze the effects
of high and low temperatures on the biology and mor-
The effects of high temperatures were studied in the
Bristol liquid nutrient medium in Gollerbach’s modiﬁ-
cation (salt composition, g/l of water:
, 3 drops of 1% solution per liter).
A nonclonal two-week-old culture of the species at the
stationary stage of growth with a starting concentration
cells/ml was used. The experiment consisted
of two series.
In the ﬁrst series, the suspension culture in tubes
was exposed in a U-2 thermostat (Germany) for 20 min
at temperatures ranging from 30 to 100
C at 10
vals. The culture was examined on days 3, 6, 14, 18, and
21. The second series of the experiment was performed
after determining the minimum temperature at which
obvious signs of algal death could be detected. In this
series, the inﬂuence of temperatures ranging from 30 to
C at 2
C intervals was studied.
To study the effect of low temperatures on the mor-
an algologically pure culture of the
alga in water was plated on the Bristol agar in Petri
dishes and incubated in a luminostat for seven days.
Thereafter, the dishes were exposed in a refrigerator at
C for 1, 5, and 9 days. Control dishes were incu-
bated at 20
The strength of effects on the alga was estimated
from the length of ﬁlaments, linear dimensions of cells,
and the presence of morphological disturbances. In the
series with high temperatures, 600 ﬁlaments and
300 cells were measured; in the series with low temper-
atures, 100 ﬁlaments and 100 cells were measured. Sta-
tistical analysis of the results included calculations of
arithmetic mean and its error, median, standard devia-
Effects of Extreme Temperatures on
L. A. Gaisina
Bashkir State Pedagogical University, ul. Oktyabr’skoi Revolyutsii 3a, Ufa, 450000 Russia;
Received March 28, 2005
: yellow-green algae,
, temperature, morphology, dimensional characters.