1067-4136/01/3204- $25.00 © 2001
Russian Journal of Ecology, Vol. 32, No. 4, 2001, pp. 255–260. Translated from Ekologiya, No. 4, 2001, pp. 280–285.
Original Russian Text Copyright © 2001 by Kuznetsova, Bayanov.
Analysis of natural communities demonstrates that
a certain combination of environmental conditions
determines the formation of certain species associa-
tions. This means that ecologists studying communities
deal with something superior to random species assort-
ments. In other words, communities with predictable
species composition occur in areas with certain combi-
nations of environmental factors. According to Pema-
, (1974), 50 plant communities are formed on
sand dunes in Wales, depending on the combination of
soil moistening, oxygen diffusion rate, pH, and sodium
concentration. Similar data were obtained for 34 com-
munities of invertebrates in rivers of southern England
, 1983). In the latter case, species rich-
ness was used as the criterion for classifying the rivers.
It was found that each stage of their subdivision into
groups with similar species compositions corresponds
to a dichotomic difference in environmental conditions,
and pH proved to be the main environmental factor. At
low pH, the species tolerant to extreme conditions
developed. Further subdivision was done taking into
account the degree of water warming in summer and
the speed of current. Thus, 34 communities of southern
English rivers were divided into ﬁve groups: two
included the communities developing at low pH; one,
the communities developing at high pH; and the
remaining two, the communities formed depending on
the combination of three factors—high pH, low sum-
mer temperatures, and rapid (or slow) current.
The purpose of our study was to classify the zoop-
lanktonic communities of lakes in the Pinega Nature
Reserve (Arkhangelsk oblast,
E). The reserve is located on the
right bank of the Pinega River, in its middle reaches,
and occupies the southeastern part of the White Sea–
Kuloi plateau, an elevated karst plain abruptly descend-
ing to the valleys of the Pinega and Kuloi rivers.
Karst rock consists of gypsum and anhydrite of the
Upper Kuloi suite of the Lower Permian. A distinguish-
ing feature of this region is the presence of water bodies
with different parameters of mineralization: the con-
tents of total dissolved solids (TDS) range from 24 to
2400 mg/l. This provides the possibility of analyzing
the zooplanktonic communities formed under condi-
tions of broad variation in TDS (by two orders of mag-
nitude). We chose nine lakes for this purpose.
MATERIALS AND METHODS
Studies were performed on lakes Lesnoe, Dolgoe,
Krugloe, Sychevo, Zheleznoe, Kumichevo, Lapozero,
Pershkovskoe, and Zapadnoe Eras’kino between 1991
and 1995. Lakes Lesnoe, Dolgoe, Krugloe, and
Sychevo were surveyed every two weeks, and other
lakes, every month in the summer seasons of 1992–
1994. Eras’kino lakes are not easily accessible and
were surveyed only occasionally in July and August
1992, 1993, and 1994. Lake Lapozero was surveyed in
the summer of 1994.
Along with zooplankton sampling, we measured
depths and water level in the lakes, as well as water
temperature, oxygen content, transparency, color, con-
ductivity, and pH. In addition, water samples for brief
chemical analysis were taken.
On the Classification of Aquatic Communities:
An Example of Zooplanktonic Cenoses of Karst Lakes
in the North of European Russia
M. A. Kuznetsova
and N. G. Bayanov
Nizhni Novgorod State University, pr. Gagarina 23, Nizhni Novgorod, 603600 Russia
Kerzhenskii State Nature Reserve, ul. Kostina 2, Nizhni Novgorod, 603134 Russia
Received November 24, 1999
—Nine lakes in the Arkhangelsk oblast were analyzed with respect to their morphometry, hydrology,
and hydrochemistry, and their zooplankton was studied for three years. The data on zooplankton abundance,
biomass, the ratio of ﬁlter-feeders and predators, the Shannon index of species diversity, and average individual
weight of zooplankters were obtained. Differences in the structure of zooplanktonic cenoses were revealed in
lakes differing in morphometric parameters, prevailing ions (HC , S ), and their concentration.
limnology, hydrobiology, communities, zooplankton, hydrochemistry, karst lakes.