1067-4136/01/3202- $25.00 © 2001
Russian Journal of Ecology, Vol. 32, No. 2, 2001, pp. 85–88. Translated from Ekologiya, No. 2, 2001, pp. 98–102.
Original Russian Text Copyright © 2001 by Lebedev, Zhuravleva, Fomicheva.
Studies on biological systems organized at the pop-
ulation level imply an analysis of relationships with
other levels of the ecological hierarchy and the environ-
ment (Whittaker, 1980; Begon,
, 1989; Mirkin,
, 1993; Rabotnov, 1995). Several
basic trends in studies on the biology of natural popu-
lations are distinguished (Yablokov, 1987).
In this work, we made an attempt to combine the
ecological approach (
1976, 1977, 1988) with the biochemical one in studies
populations. It is appropriate to
recall that Sukachev (1975) justly emphasized the
importance of chemical studies of plant communities,
as the latter play the greatest role in the formation of
biogeocenoses and represent a laboratory where the
accumulation and interconversion of matter and energy
take place. We were aware that the results of such stud-
ies are principally difﬁcult to interpret unambiguously,
as this has already been noted by Yablokov (1987).
MATERIALS AND METHODS
Our studies were performed in the village of Sever-
nyi (Kostroma raion, Kostroma oblast) from 1996 to
is a widespread ruderal species
that weeds the crops of all cultivated plants, including
forage grasses, and occurs in meadows, river valleys,
along roads, and on wasteland. In these communities,
usually dominates, forming a mosaic of
spots ranging from one square meter to dozens and
even hundreds of square meters in area.
With respect to its life form,
is an oblig-
atorily creeping-rooted herbaceous perennial. Its
ontogeny, structure of adult individuals, speciﬁc fea-
tures of reproduction, and characteristics of the ontoge-
netic composition of populations under different eco-
logical conditions were studied by several researchers
(Rauh, 1937; Kutschera, 1960; Özer, 1969; Lebedev,
1991a, 1991b, 1993, 1995). An adult
represents a system of uneven-aged shoots (root suck-
ers) that have developed from adventitious buds on
propagation roots. The latter initially grow horizontally
(plagiotropically) and then, at some distance, bend and
grow vertically downward to a depth of more than 1 m.
At the root bend, adventitious buds are formed. In ﬁeld
communities, the site of the bend is located at a depth
of more than 20 cm, i.e., below the arable layer. Cutting
the shoots upon plowing stimulates the formation and
growth of buds. One or two young propagation roots
extend from the plagiotropic part or the base of the
orthotropic part of the ﬁrst-order propagation root.
plants growing in the ﬁelds, meadows,
old fallows, forest stands, the valleys of rivers and
lakes, or other disturbed areas reproduce only vegeta-
tively, following the pattern of normal particulation. It
involves the separation of propagation roots with buds
from the mother root, which dies off and decomposes
after two to three years. Sometimes, the plagiotropic
part also dies off after the development of the root
sucker, so that the descendant may appear to be a plant
of seed origin, with the main root.
The type of root sucker development may be mono-,
di-, and tricyclic. The suckers have the underground
(root) part with numerous adventitious roots and the
aboveground (assimilating) part.
In population studies, a root (or a root sucker) was
taken as a unit of counting (Zhuravleva
Cenopopulations were studied in two communities: in
a fallow uncultivated for many years and on the sloping
bank of an artiﬁcial pond. The latter was 2 m wide and
had a grade of 70 degrees. Both areas have been
exposed to anthropogenic impact (plowing in the ﬁrst
case and excavation and earth moving in the second)
and are currently used as grazing grounds for cattle.
The geobotanical analysis of communities was per-
Specific Features of the Population Ecology of Creeping Thistle,
(L.) Scop. s. l.
V. P. Lebedev, I. V. Zhuravleva, and G. K. Fomicheva
Nekrasov State University, ul. Pervogo Maya 14, Kostroma 156001, Russia
Received April 13, 1999
—Two populations of creeping thistle (
) growing in a ﬁeld uncultivated for many
years and on the sloping bank of an artiﬁcial pond were studied with respect to the demographic and chemical
composition. The results showed that the contents of some elements in plants depend on speciﬁc features of the
soil and plant population parameters (abundance, biomass, and ontogenetic composition). Some indices of the
content of mineral substances in the population and soil proved to be difﬁcult to interpret unambiguously.
: population, ontogeny, demographic and chemical composition.