Age spectrum. Modern problems of science and education

INTRODUCTION

Russian hazel grouse ( Fritillaria ruthenica Wikstr.) is a species from the Liliaceae family. F.ruthenica listed in the Red Book of Russia, in the regional Red Books of Saratov, Volgograd, Samara, Penza, Lipetsk, Tambov, Bryansk regions. Study of age states of coenopopulations F. ruthenica in the Balashovsky district, as a rare and protected species of plant is relevant, which determines the purpose of this study.

This is a perennial bulbous herbaceous plant with drooping flowers (life expectancy up to 20 years). The perianth is simple, corolla-shaped, six-membered. The fruit is a capsule. This is a Eurasian species. Leaf growth begins in the second ten days of April and continues until the second ten days of May. Growing season duration F. ruthenica to different age periods from 30 to 80 days. Depending on the timing and time of soil thawing, fluctuations between the dates of the beginning of the growing season in some years can reach 20-22 days. During the summer dormancy period, only the bulb is preserved. F. ruthenica reproduces both by seeds and vegetatively (by renewal buds from bulbs or adventitious brood buds). F. ruthenica- xeromesophyte. Demanding on soils.

Category and status F. ruthenica in the Saratov region 2 (V) - vulnerable species. It grows in steppe meadows, among shrubs, on the edges and clearings of deciduous forests, in steppe oak forests, and on rocky chalk slopes. The limiting factors are collection by the population and violation of the integrity of habitats.

MATERIALS AND METHODS OF RESEARCH

To study the state of coenopopulations F. ruthenica Test plots measuring 1x1 m were laid out. At each trial plot, the total number of individuals per 1 m 2 was taken into account. U F. ruthenica The following biometric indicators were measured: height, number of lower, middle and upper leaves, number of flowers, length of tepals. When analyzing these indicators, the age states of individuals were determined and ontogenetic spectra were compiled. When determining the age structure of the population, individuals of seed and vegetative origin were taken as the accounting unit. Age conditions were determined according to the Works of M.G. Vakhromeeva, S.V. Nikitina, L.V. Denisova, I. Yu. Parnikoza. Recovery, age and efficiency indices were determined according to the method of A.A. Uranova. The recovery index shows how many descendants there are per generative individual at a given moment. The age index evaluates the ontogenetic level of CP at a specific point in time; it varies in the range of 0-1. The higher its indicator, the older the CPU under study. The efficiency index, or average energy efficiency, is the energy load on the environment, called the "average" plant. It also varies from 0 to 1, and the higher it is, the older the age group of the “average” plant.

III. Generative	Generative young (early)
	Generative middle-aged (adult)

	Generative old (late)

IV. Postgenerative	Subsenile (old vegetative)
ny (senile, gray)	Senile
	Dying

above the soil surface level; when underground, for example, near an oak tree, they remain in the soil. The first leaves, for example those of spruce, are thin, short (up to 1 cm long), round in cross-section and often located.

3. Juvenile plants. Plants that have lost connection with the seed

A also cotyledons, but have not yet acquired the features and characteristics of an adult plant. They are easy to organize. They have childish (infantile) structures. Their leaves are small in size, not typical in shape (in spruce they are similar to the needles of seedlings), and there is no branching. If branching is pronounced, then it is qualitatively different from the branching of immature individuals. They are characterized by high shade tolerance, being part of the herbal but-shrub layer.

4. Immature plants. They are characterized by transitional characteristics and properties from juvenile to adult vegetative individuals. They are larger, develop leaves in shape more similar to the leaves of adult plants, and have pronounced branching. The nutrition is autotrophic. At this stage, the main root dies off, adventitious roots and tillering shoots develop. Immature trees are part of the understory layer. In low light conditions, individuals are delayed in development and then die off. In young children, this stage is usually not recorded. In spruce it is usually observed in the fourth year of life.

The identification of immature plants is most difficult and some authors combine them into one group with virginile plants.

5. Virgin plants. They have morphological features typical for the species, but do not yet develop generative organs. This is the phase of preparing the morphophysiological basis for achieving physiological maturity, which will occur at the next stage. Virgin trees have almost fully formed features of an adult tree. They have a well-developed trunk and crown, and maximum height growth. They are part of the tree canopy and experience the maximum need for light.

6. Generative young plants. Characterized by the appearance of the first generative organs. Flowering and fruiting are not abundant, the quality of the seeds may still be low. Complex changes occur in the body to ensure the generative process. The processes of neoplasms prevail over death. The growth of trees in height is intensive.

7. Generative middle-aged plants. In this age state, individuals reach their maximum size, are distinguished by large annual growth, abundant fruiting, high quality seeds The processes of new growth and death are balanced. The apical growth of some large branches of trees stops, and dormant buds awaken on the trunks.

8. Generative old plants. Annual growth is weakened, the indicators of the generative sphere are sharply reduced, and the processes of death prevail over the processes of new formation. The trees are actively awakening dormant buds, and the formation of a secondary crown is possible. Seeds are produced irregularly and in small quantities.

9. Subsenile plants. They lose the ability to develop the generative sphere. Dying processes predominate; secondary appearance of transitional (immature) type leaves is possible.

10. Senile plants. They are characterized by features of general decrepitude, which is expressed in the death of parts of the crown, the absence of renewal buds and other neoplasms; possible secondary appearance of some juvenile features. Trees usually develop a secondary crown and the upper part of the crown and trunk dies.

11. Dying plants. Dead parts predominate; there are single viable dormant buds.

The listed age-related conditions are characteristic of polycarpics. Diagnoses and age-related condition keys have been developed for a range of herbaceous plants.

And tree species (Diagnosis and keys..., 1980, 1983, 1989; Romanovsky, 2001). In monocarpics, the generative period is represented by only one age state, and the postgenerative period is completely absent.

In animals, with varying degrees of accuracy, individuals are usually distinguished as “young”, “yearlings”, “yearlings”, “adults”, “old”. G.A. Novikov (1979) distinguishes five age groups of animals:

1. Newborns (until the time of sight).

2. Juveniles are growing individuals that have not yet reached sexual maturity.

3. Sub-adults – close to puberty.

4. Adults are sexually mature individuals.

5. Old are individuals that have stopped reproducing.

V.E. Sidorovich (1990) distinguished three age groups in otter populations: young individuals (first year of life), semi-adults (second year of life), adults (third year of life and older). In the Belovezhskaya bison population, adults make up 57.8%, young animals (from 1 year to 3.5 years) - 27.9, young of the year - 14.3% (Bunevich, 1994). Age-related differences are most clearly manifested in species whose development occurs with metamorphosis (egg, larva, pupa and adult).

Individuals of different age groups, both in plants and animals, inevitably developing in different conditions, differ markedly not only in morphological, but also in quantitative indicators. They have biological and physiological differences, play different roles (plants) in the formation of communities, in biocenotic relationships. Seeds in plant populations, for example, being dormant, express the potential capabilities of the population. Seedlings have mixed nutrition ( nutrients endosperm and photosynthesis), juveniles and individuals of subsequent groups are autotrophs. Generative plants perform the function of self-sustaining population. The role of individuals in the life of the population, starting with subsenile plants, is weakening. Dying plants leave the population. During the process of ontogenesis, many species change their life form, as well as their attitude and degree of resistance to environmental factors.

The identification of age groups is always difficult, especially in animals, and is carried out using different methods. Most often, attention is paid to the time of transition to the generative state. Age of puberty different types comes in different terms. In addition, the timing of maturation of individuals in different populations of the same species is also different. In some populations of ermine (Mustela erminea), the phenomenon of neoteny is manifested - mating of still blind 10-day-old females (Galkovskaya, 2001). Beluga females mature at 15-16 years, males at 11 years. Under favorable conditions, beluga can enter rivers to spawn up to 9 times. During the river period of life, females do not feed. Repeated maturation is observed after 4-8 years (females) and 4-7 years (males). The last spawning occurs at the age of about 50 years. The post-reproductive period lasts 6-8 years (Raspopov, 1993). Much earlier, at four or five years of age, females reach sexual maturity polar bear. Reproduction continues until the age of 20, repeats on average every 2 years, average litter size is 1.9 cubs

(Kuzmina, 2002).

The differences between age groups are also quite significant and species-specific in animals. In species with direct development, differences associated with reproduction, nutrition and functional development are clearly visible.

role. Young individuals determine the potential for future reproduction, while mature individuals carry out reproduction. In bank vole (Clethrionomys glareolus) populations, individuals of spring and summer cohorts quickly mature, marry early, and are fertile, contributing to an increase in population size and expansion of its range. However, their teeth wear out quickly, they age early and live mostly 2-3 months. A small number of individuals survive until the spring of next year. As a rule, animals of the latest generations hibernate. They have small body sizes, much less than the relative weight of most internal organs(liver, kidneys), reduced rate of tooth abrasion, i.e. there is a sharp slowdown in growth. In addition, they have a very low mortality rate in winter. In terms of physiological state, wintering voles correspond to approximately month-old individuals of the spring-summer generations. They give birth and soon die off. Their descendants - individuals of early spring cohorts, distinguished by early maturation and fertility, quickly replenish the population thinned out during the non-reproductive period, closing the annual cycle (Shilov, 1997).

Thanks to the biological characteristics of wintering individuals, energy costs are reduced to a minimum during the most difficult time for the population. They successfully “drag” the population through the winter (Olenev, 1981). A similar pattern was noted in other rodent species. In steppe pieds (Lagurus lagurus), born in May, the average age of reaching maturity was 21.6 days, and in those born in October, it was 140.9 days (Shilov, 1997). According to S.S. Schwartz, the experience of unfavorable conditions occurs in a state of “canned youth.” It is the increase in life expectancy of rodents of later cohorts that occurs not due to survival in old age, but by prolonging the physiologically youthful period (Amstislavskaya, 1970).

The generative period in woody plants (we noted in 230 species) also occurs at different times. The earliest dates (4-5 years) were observed in species of a few genera (willow, rowan, plum, bird cherry, ash maple); the latest (40 years) is found in forest beech. A very long pregenerative period of ontogenesis is a feature of the reproductive strategy of woody plants. Shrub species are distinguished by a relatively early (3-4 years) transition from virginity (Fedoruk, 2004).

coniferous species occurs during the maximum growth of the tree in height (Nekrsova, Ryabinkov, 1978; Shkutko, 1991; Fedoruk, 2004); with intensive radial growth of the trunk (Valisevich, Petrova, 2004). The faster the upward growth curve goes, the earlier the woody plant enters the reproductive phase. Physiological and structural changes in plants are associated with the maximum linear increase in height. Fast growth allows plants to achieve a certain morphological structure and linear dimensions in a short time. With the attenuation of the culmination of height growth due to the redistribution of plastic substances, stable flowering and fruiting begins. Herbaceous plants also begin to bear fruit at a certain threshold value of vegetative mass.

sy (Smith and Joung, 1982).

According to M.G. Popov (1983), as the amount of meristem begins to decrease and “the body becomes overgrown with a shell, the armor of permanent tissues,” its ability to grow decreases, the process of generative development begins, and with further depletion of the meristem, aging occurs . The mechanism of this phenomenon is very complex and far from clear. It is assumed that quantitative changes in metabolism lead to the activation of inert genes, the synthesis of specific RNAs and qualitatively new reproductive proteins (Berne, Kune, Saks, 1985, cited in: Valisevich, Petrova, 2004). Yu.P. Altukhov (1998) showed on botanical and zoological species that the greater the proportion of “heterotic” genes included in the processes of growth and puberty, the greater the energy expenditure of the organism in the pregenerative period of ontogenesis and the earlier the onset of sexual maturity.

Table Age of seed production and culmination of growth

in height of coniferous plants

Plant	Beginning of the family	The beginning of the cultural	Maximum
	wearing, go-		ny growth
		growth in	in height, th-
		height, years
Siberian fir

Fir one color

White fir

Balsam fir

Fir Vicha
Menzies's Pseudo-tsuga

Norway spruce
Gray spruce

Prickly spruce
European larch

Kaempfer's larch

Polish larch
Siberian larch
Larch Sukacheva
Weymouth pine

Siberian cedar pine
Scots pine

Rumelian pine
Austrian black pine

Pine is hard
Banks Pine

Thuja occidentalis

As a rule, different age groups of animals have different nutritional spectrums. Tadpoles, for example, are aquatic phytophages, frogs are zoophages leading a terrestrial lifestyle. Individuals of each age cohort of the brown hare (Lepus europaeus) are oriented towards different food resources; Each litter of mouse-like rodents also has its own food supply.

Differences in age groups in animals characterized by development with metamorphosis are no less clearly expressed. Adults of the cockchafer (Melolontha hippocastani) feed on tree leaves, while larvae feed on humus and plant roots. Cohorts are confined to different soil layers and, depending on its temperature and humidity, and the availability of food, the beetles emerge at different times, which provides the population with numerous adaptive strategies. The food of the cabbage butterfly (Pieris brassicae), the largest among local garden whites, is the nectar of cruciferous plants, while the caterpillars eat cabbage leaves. At the same time, young caterpillars, grayish-green, with black dots and a light yellow stripe on the dorsal side, scrape off the pulp of the leaf; grown individuals make small holes in the leaves; older caterpillars, colored green, with bright black spots and three bright yellow stripes, eat the entire leaf except for large veins. Larvae younger ages Mole crickets (Gryllotalpa gryllotalpa) feed on humus and plant roots that grow into the nesting chamber. The main food of older larvae and adults are earthworms, insect larvae, underground parts of plants, which causes great damage to cultivated plants, especially in vegetable gardens and greenhouses.

In forms with strict attachment of individual stages of development to a specific host species, for example in aphids, “trophic polymorphism” is determined by the number of hosts. Complex life cycles with larval stages allow species to use more than one habitat or food resource. Sexual generations of bean aphids, for example, feed

leaves of euonymus, viburnum, and asexual ones, in the second half of summer - leaves of vegetable plants.

Age structures of populations are expressed as age spectra. Reflecting the age structure begins with establishing a basic age spectrum. The basic age spectrum acts as a reference against which the age states of the studied populations of a given species are compared. The age spectra of specific coenopopulations, as a rule, deviate from the basic, generalized version. Theoretically, the amplitude of these oscillations fits into the zone M±3α, where M is the average value of the relative amount (in%) of each age group, α is the standard deviation (Zaugolnova, 1976). According to N.V. Mikhalchuk (2002), in the conditions of Brest and Pripyat Polesie, the basic age spectrum of the lady’s slipper is classified as single-vertex type with an absolute maximum in the integral group “v+sv”. It is characterized by the following ratio of ontogenetic groups (%): J - 3.0; im - 10.5%; v+sv - 39; g1 – 20.8; g2 – 11.0; g3 – 6.0; ss – 6.8; s – 2.9).

Basic age spectra have been developed for coenopopulations of many herbaceous species (Fig. ...). They are considered as one of the biological indicators of the species, and deviations reflect the state of a particular coenopopulation. Coenopopulations of the lady's slipper were assessed using these age spectra as “very good” (within the confidence zone of the base spectrum the characteristics of 7-8 age groups out of 8 identified are located), “good”, “satisfactory”, “unsatisfactory” and “threatening” (beyond the boundaries of the monitoring zone there are characteristics of 7-8 age groups) (Mikhalchuk, 2002).

There are four types of base spectra. Within each type, several options are distinguished depending on the methods of self-maintenance, the course of ontogenesis of individuals and the characteristics of its implementation in the phytocenosis (Zaugolnova, Zhukova, Komarov, Smirnova, 1988).

1. Left-handed spectrum. Reflects the predominance in the population of individuals of the pregenerative fraction or one of the groups of this fraction. Characteristic of trees and some groups of grasses (Fig.).

2. Single-vertex symmetric spectrum. The population contains individuals of all age states, but mature generative individuals predominate, which is usually expressed in species with weak aging.

3. Right-handed spectrum. Characterized by a maximum of old generative or senile individuals. The accumulation of old individuals is most often associated with the long duration of the corresponding age states.

4. Bimodal (two-vertex) spectrum. Two maxima are observed, one in the young part, the other in the composition of mature or old generative

plants (two modal groups). Characteristic of species with a significant life expectancy and a well-defined period of aging.

Herbaceous plants of broad-leaved forests, according to O.V. Smirnova (1987), are characterized by different types of basic age spectra (table).

Table Distribution of herbaceous plants of broad-leaved forests by

types and variants of basic age spectra (Smirnova, 1987)

Methods of self-support	Types of base spectra
expectations and their options	(according to the position of the main maximum)
	I (p – g1 )*	II (g2)			III (g3–ss)
Seminal		Gravilat city-
	corydalis,	sky, rank of age

		Kashubian,
		oak forest face,
	intoxicating,	sedge
	Robert's geranium


	speckled
Vegetative
	blue onion	obnoxious
deeply rejuvenated
rudiments, deep and
shallowly rejuvenated-
new beginnings
shallowly rejuvenated-					It's common to whine
rudiments (phyto-					novena
cenotically incomplete		hairy,
member spectra)		woodsman many-
		year old,





			star-
		Ka lanceolate, Violet
	(deeply rejuvenated)
wifely rudiments)		Geneva
seed and vegetative
ny (deep and shallow
side-rejuvenated for-

seed and vegetative		bear onion,		Poagrass oak-
	(shallow	hoof euro-		equal, sedge
wifely rudiments)		Peisky, honey-		palmate,
				sedge

		flowering, in-

		ordinary,
		tenacious creep-

* - I – left-sided spectrum; II – centered spectrum; III – right-handed spectrum.

Depending on the ratio of age groups, invasive, normal and regressive populations are distinguished. The classification was proposed by T.A. Rabotnov (1950) in accordance with the three stages of development of a coenopopulation as a system: emergence, full development and extinction.

1. Invasive population. Consists mainly of young (pregenerative) individuals. This is a young population, which is characterized by the process of development of the territory and the introduction of germs from the outside. She is not yet capable of self-sustainment. These populations are usually characteristic of cleared areas, burnt areas, and disturbed habitats. They develop especially successfully in the field after continuous plowing. In addition to local species, invasive coenopopulations are formed by introduced woody species. Saskatoon serviceberry, viburnum-leaved bladdercarp, banksa pine, ash-leaved maple and some other species are introduced into natural undisturbed or slightly disturbed cenoses without significantly affecting them general structure. The implementation process is very complicated and involves a lot of waste. Self-seeding of balsam fir, including seedlings, juvenile, immature and virginal plants, under oxalis growing conditions amounted to 40 thousand specimens/ha (left-sided spectrum) (Fig.). Over 12 years it decreased to 14.0, and over the next 9 years its number decreased to 6 thousand specimens/ha. Once under the canopy of the tree layer, virgin plants are characterized by slow development,

many enter secondary rest. The transition of individuals to the generative state is gradual. The generative generation is in the stage of increasing vegetative and generative power. Gradually, the introduced population acquires a characteristic phenological appearance, usually forming on the basis of a small number of founder individuals.

2. Normal population. Includes all (or almost all) age groups of organisms. It is distinguished by its stability, the ability to self-sustain by seed or vegetative means, full participation in the structure of the biocenosis, and independence from the external supply of germs. These populations are either normally complete or normal incomplete. Populations with a full age spectrum are a characteristic feature of established indigenous climax communities.

3. Regressive population. In such populations, postgenerative age groups of individuals predominate. There are no young individuals. In this state, they have lost the ability to self-sustain, gradually degrade and die. Regressive populations of silver birch in forests include many of the oldest birch forests, in which the species does not regenerate under the birch canopy, and spruce undergrowth, which makes up its invasive population, develops abundantly. The only white fir coenopopulation in Belarus in the Tisovka tract (Belovezhskaya Pushcha) was in a degraded state, mainly due to the reclamation of the swamp massif.

Age states reflect the dynamic state of the population. In its development, it usually goes through invasive, normal and regressive stages. In each case, the age structure of the population is determined biological features type and depends on environmental conditions. Year-to-year variability in the age composition of fine bentgrass

(Agrostis tenuis) reflects the rice….

The role of age structure in the life of a population is great. Different nutritional spectra of age cohorts soften intraspecific competitive relationships, use resources more fully, and increase population resistance to unfavorable environmental factors, since individuals of different cohorts have different adaptive potential. Thus, young individuals of woody plants successfully endure harsh winters under snow, under the cover of fallen leaves and withered herbaceous plants. In snowless, harsh winters, the potential for survival is highest for seeds that are dormant. Juvenile plants resist drought by closing their stomata early in the day, using up absorbed carbon; mature trees use groundwater(Cavander-Bares, Bazzaz, 2000). Age heterogeneity is also important for the exchange of information between individuals and serves the purpose of continuity in the population.

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4.3. Age structure

Age structure determined by the ratio of different age groups of individuals in the population. Age, or ontogenetic, condition is defined as the physiological and biochemical state of an individual, reflecting a certain stage of ontogenesis. Individuals of the same age state are functionally similar, but may have different absolute or calendar ages. Absolute age is measured by the lifespan of an organism or a given cohort of individuals in a population from the moment the individual appears until the time of observation. In a population and in a cenosis, it is not the absolute age, but the age state that reflects the biological role of individuals, and therefore a comparative assessment of the role of species in the community is carried out based on them.

Age structure of plant populations. The basis for identifying the age states of plants is a complex of qualitative traits. The expression of ontogenetic states is mainly morphological changes, which are most easily visually captured and correlatively associated with other age-related changes in the body.

The idea of age as a stage individual development individuals formed the basis for numerous periodizations of morphogenesis. The classification of age states of plants by Rabotnov (1950) is generally accepted. According to his classification, plants are distinguished into 11 age states, corresponding to four periods of ontogenesis (Table 3). The ratios of the duration of these periods in different species are very different (Fig. 44).

Rice. 44. The ratio of the duration of pre-reproductive (7), reproductive (2) and post-reproductive (2) periods of ontogenesis in some species (according to A.V. Yablokov, 1987)

Dormant seeds– seeds (embryonic individuals), separated from the parent individual and, after dissemination, existing independently in the soil (on the soil).

Sprouts– small non-branching plants with the presence of embryonic structures (cotyledons, embryonic roots, shoots with small, simpler leaves than those of an adult plant) and mixed nutrition (due to seed substances, assimilation of cotyledons and first leaves). During aboveground germination, the cotyledons are carried above the soil surface; when underground (near oak) - remain in the soil. The first leaves (of spruce) are thin, short (up to 1 cm long), rounded in cross-section and often located.

Table 3

Classification of age states of seed plants (according to Rabotnov, 1950)

*Indices of age conditions are adopted according to A.A. Uranov (1973)

Juvenile plants - plants that have lost connection with the seed, cotyledons, but have not yet acquired the features and characteristics of an adult plant. They are easy to organize. They have childish (infantile) structures. Their leaves are small in size, not typical in shape (in spruce they are similar to the needles of seedlings), and there is no branching. If branching is pronounced, then it is qualitatively different from the branching of immature individuals. They are characterized by high shade tolerance, being part of the herb-shrub layer.

Immature plants are characterized by transitional characteristics and properties from juvenile to adult vegetative individuals. They are larger, with pronounced branching, and develop leaves that are more similar in shape to the leaves of adult plants. The nutrition is autotrophic. At this stage, the main root dies off, adventitious roots and tillering shoots develop. Immature trees are part of the understory layer. In low light conditions, individuals are delayed in development and then die off. In young children, this stage, as a rule, is not recorded. In spruce it is usually observed in the fourth year of life. Isolation of immature plants is most difficult, and some authors combine them into one group with virginile plants.

Virgin plants have morphological features typical of the species, but do not yet develop generative organs. This is the phase of preparing the morphophysiological basis for achieving physiological maturity, which will occur at the next stage. Virgin trees have almost fully formed features of an adult tree. They have a well-developed trunk and crown, and maximum height growth. They are part of the tree canopy and experience the maximum need for light.

Generative young plants characterized by the appearance of the first generative organs. Flowering and fruiting are not abundant, the quality of the seeds may still be low. Complex changes occur in the body to ensure the generative process. The processes of neoplasms prevail over death. The growth of trees in height is intensive.

Generative middle-aged plants reach maximum size, are distinguished by large annual growth, abundant fruiting, and high quality seeds. The processes of new growth and death are balanced. The apical growth of some large branches of trees stops, and dormant buds awaken on the trunks.

Generative old plants– plants, the annual growth of which is weakened, the indicators of the generative sphere are sharply reduced, the processes of death prevail over the processes of new formation. The trees are actively awakening dormant buds, and the formation of a secondary crown is possible. Seeds are produced irregularly and in small quantities.

Subsenile plants lose the ability to develop the generative sphere. Dying processes predominate; secondary appearance of transitional (immature) type leaves is possible.

Senile plants are characterized by features of general decrepitude, which is expressed in the death of parts of the crown, the absence of renewal buds and other neoplasms; possible secondary appearance of some juvenile features. Trees usually develop a secondary crown and the upper part of the crown and trunk dies.

Dying plants have single viable dormant buds, dead parts predominate.

The listed age-related conditions are characteristic of polycarpics. In monocarpics, the generative period is represented by only one age state, and the postgenerative period is completely absent. Age-related conditions are determined using specially developed diagnoses and keys (Fig. 45, 46).

Age structure of populations in animals. U Animals are usually distinguished between young individuals, underyearlings, yearlings, adults and old ones. Some authors distinguish five age groups of animals: newborns (until the time of maturity); young (growing individuals who have not yet reached sexual maturity); sub-adults (close to puberty); adults (sexually mature individuals); old (individuals that have stopped reproducing). V.E. Sidorovich distinguished three age groups in otter populations in Belarus: young individuals (first year of life), semi-adults (second year of life), adults (third year of life and older). In the Belovezhskaya bison population, adults make up 57.8%, young animals (from 1 to 3.5 years) - 27.9, young of the year - 14.3%.

It is difficult to distinguish age groups in animals. Most often, attention is paid to the time of transition of an individual to the generative state. The age of sexual maturity occurs at different times in different species. In addition, the timing of maturation of individuals of the same species in different populations is also different. In some populations of ermine (Mustela erminea), the phenomenon of neoteny is manifested - mating of still blind 10-day-old females. Beluga females mature at 15–16 years, males at 11 years. Under favorable conditions, beluga can enter rivers to spawn up to 9 times. During the river period of life, females do not feed. Repeated maturation is observed after 4–8 years (females) and 4–7 years (males). The last spawning occurs at the age of about 50 years. The post-reproductive period lasts 6–8 years. Much earlier, at 4 or 5 years of age, female polar bears reach sexual maturity. Reproduction continues until the age of 20, repeating on average every 2 years, the average litter size is 1.9 cubs. Age-related differences are most clearly manifested in species whose development occurs with metamorphosis (egg, larva, pupa and adult).

Rice. 45. Age conditions of Norway spruce (according to Yu.E. Romanovsky, 2001):

j- juvenile; im- g- generative

Individuals of different age groups in both plants and animals, inevitably developing in different conditions, differ markedly not only in morphological, but also in quantitative indicators. They have biological and physiological differences and play different roles in the composition of communities and in biocenotic relationships. In plant populations, seeds, for example, being dormant, express the potential capabilities of the population. Seedlings have mixed nutrition (endosperm nutrients and photosynthesis), juveniles and individuals of subsequent groups are autotrophs. Generative plants perform the function of self-sustaining population. The role of individuals in the life of the population, starting with subsenile plants, is weakening. Dying plants leave the population. During the process of ontogenesis, many species change their life form, as well as their attitude and degree of resistance to environmental factors.

Rice. 46. Age conditions of middle plantain (according to L.A. Zhukova, 1980):

j- juvenile; im- immature; v – virgin; g- generative young; g 2– generative middle age; g 3 - generative old; ss- subsenile; s – senile

In animals, differences between age groups are also very significant and species-specific. In bank vole (Clethrionomys glareolus) populations, according to Shilov (1997), individuals of the spring and summer cohorts quickly mature, marry early, and are fertile, contributing to an increase in population size and an increase in its range. However, their teeth wear out quickly, they age early and live mostly 2–3 months. A small number of individuals survive until the spring of next year. As a rule, animals of the latest generations hibernate. They have small body sizes, a much smaller relative mass of most internal organs (liver, kidneys), a reduced rate of tooth wear, i.e., a sharp inhibition of growth is expressed. In addition, they have a very low mortality rate in winter. In terms of physiological state, wintering voles correspond to approximately month-old individuals of the spring-summer generations. They give birth and soon die off. Their descendants - individuals of early spring cohorts, distinguished by early maturation and fertility, quickly replenish the population thinned out during the non-reproductive period, closing the annual cycle.

Thanks to the biological characteristics of wintering individuals, energy costs are reduced to a minimum during the most difficult time for the population. They successfully “drag” the population through the winter. A similar pattern was noted in other rodent species. In steppe pieds (Lagurus lagurus) born in May, the average age of reaching maturity was 21.6 days, and in those born in October - 140.9 days. As Schwartz puts it, experiencing unfavorable conditions occurs in a state of “canned youth.” The increase in life expectancy of rodents of later cohorts is not due to survival in old age, but by prolonging the physiological period of adolescence.

The process of transition of a plant or animal from a virginal state to a generative state is determined by a specific genetic program and is regulated by many factors. For plants, this is primarily temperature, daylight hours, and position in the phytocenosis. The onset of maturity of individuals in Siberian fir (Abies sibirica) cenoses of the same age ranges from 22 to 105 years. It has been noted that the formation of the first generative organs in coniferous species occurs during the maximum growth of the tree in height, as well as during intensive radial growth of the trunk. The faster the growth curve goes up, the earlier the woody plant enters the reproductive phase. Physiological and structural changes in plants are associated with the maximum linear increase in height. Rapid growth allows plants to achieve a certain morphological structure and linear dimensions in a short time. With the attenuation of the culmination of height growth due to the redistribution of plastic substances, stable flowering and fruiting begins. Herbaceous plants also begin to bear fruit at a certain threshold value of vegetative mass and the development of storage organs.

According to M.G. Popov, as the amount of meristem begins to decrease and “the body acquires a shell, the armor of permanent tissues,” its ability to grow decreases, the process of generative development begins, and with further depletion of the meristem, aging occurs. The mechanism of this phenomenon is very complex and not fully understood. It is assumed that quantitative changes in metabolism lead to the activation of inert genes, the synthesis of specific RNAs and qualitatively new reproductive proteins. Yu.P. Altukhov showed: the greater the proportion of “heterotic” genes included in the processes of growth and puberty, the greater the energy expenditure of the organism in the pregenerative period of ontogenesis and the earlier puberty occurs.

Age spectra. Age structures of populations are expressed in the form of age spectra, reflecting the distribution of individuals in a population according to age states. The study of age structure begins with establishing a basic age spectrum. Basic age spectrum acts as a reference (typical) with which the age states of the studied populations of a given species are compared. It is considered as one of the biological indicators of the species, and deviations reflect the state of a particular coenopopulation.

There are four types of base spectra (Fig. 47). Within each type, several options are distinguished depending on the methods of self-maintenance, the course of ontogenesis of individuals and the characteristics of its implementation in the phytocenosis.

Left-handed spectrum reflects the predominance in the population of individuals of the pregenerative period or one of its age groups. Characteristic of trees and some grasses.

Single-vertex symmetric spectrum reflects the presence in the population of individuals of all age states with a predominance of mature generative individuals, which is usually expressed in species with weak aging.

Right-handed spectrum characterized by a maximum of old generative or senile individuals. The accumulation of old individuals is most often associated with the long duration of the corresponding age states.

Rice. 47. Types of basic spectra of cenopopulations (average indicators) (from L.B. Zaugolnova, L.A. Zhukova, A.S. Komarova, O.V. Smirnova, 1988):

A- left-sided (meadowsweet); b - single-vertex symmetrical (Valis fescue); V– right-sided (meadow fescue); d – two-vertex (feather feather grass)

Bimodal (two-vertex) spectrum has two maxima: one in the young part, the other in the composition of mature or old generative plants (two modal groups). Characteristic of species with a significant life expectancy and a well-defined period of aging.

Ratio of age groups. Based on the ratio of age groups, populations are distinguished between invasive, normal and regressive. The classification was proposed by Rabotnov in accordance with the three stages of development of a coenopopulation as a system: emergence, full development and extinction.

Invasive population consists predominantly of young (pregenerative) individuals. This is a young population, which is characterized by the process of development of the territory and the introduction of germs from the outside. She is not yet capable of self-sustainment. Such populations are usually characteristic of cleared areas, burnt areas, and disturbed habitats. They develop especially successfully in places after continuous plowing. In addition to local species, invasive coenopopulations are formed by introduced woody species. Saskatoon serviceberry, viburnum-leaved bladdercarp, banksa pine, ash-leaved maple and some other species invade natural undisturbed or slightly disturbed cenoses without significantly affecting their overall structure. The implementation process is very complicated and involves a lot of waste. Self-seeding of balsam fir, including seedlings, juvenile, immature and virginal plants, amounted to 40 thousand specimens/ha (left-sided spectrum) in oxalis growing conditions. Over 12 years it decreased to 14 thousand, and over the next 9 years its number decreased to 6 thousand specimens/ha. Once under the canopy of the tree layer, virginal plants are characterized by slow development; many enter secondary dormancy.

Population normal includes all (or almost all) age groups of organisms. It is distinguished by its stability, the ability to self-sustain by seed or vegetative means, full participation in the structure of the biocenosis, and independence from the external supply of germs. These populations are normal full-membered or normal incomplete. Populations with a full age spectrum are a characteristic feature of established communities.

Population regressive 2
It is more correct to call it a “regressive population”.

Characterized by a predominance of post-generative age groups of individuals. There are no young individuals. In this state, populations lose the ability to self-sustain, gradually degrade and die off. Regressive populations of silver birch in forests include many of the oldest birch forests, in which the species does not regenerate under the birch canopy, and spruce undergrowth, which makes up its invasive population, develops abundantly. The only cenopopulation of white fir in Belarus (Belovezhskaya Pushcha) found itself in a degraded state, mainly due to the reclamation of the swamp massif.

Age states reflect the dynamic state of the population. In its development, it usually goes through invasive, normal and regressive stages. In each case, the age structure of the population is determined by the biological characteristics of the species and depends on environmental conditions. It should be used to guide the exploitation of natural populations of animals and plants.

The significance of different qualities of age-related conditions. Different nutritional spectra of individuals of age groups soften intraspecific competitive relationships, use resources more fully, and increase the population's resistance to unfavorable environmental factors, since individuals of different age groups have different adaptive potential. Tadpoles, for example, are aquatic phytophages, frogs are zoophages leading a terrestrial lifestyle. Adults of the cockchafer (Melolontha hippocastani) feed on tree leaves, while larvae feed on humus and plant roots. Cohorts are confined to different soil layers and, depending on its temperature and humidity, and the availability of food, the beetles fly out at different times, which provides the population with numerous adaptive strategies. The food of the cabbage butterfly (Pieris brassicae), the largest among local garden whites, is the nectar of cruciferous plants, the food of the caterpillars is cabbage leaves. At the same time, young caterpillars, grayish-green, with black dots and a light yellow stripe on the dorsal side, scrape off the pulp of the leaf; grown individuals make small holes in the leaves; older caterpillars, colored green, with bright black spots and three bright yellow stripes, eat the entire leaf, except for the large veins. Younger larvae of the mole cricket (Gryllotalpa gryllotalpa) feed on humus and plant roots that grow into the nesting chamber. The main food of older larvae and adults are earthworms, insect larvae, underground parts of plants, which causes great damage to cultivated plants, especially in vegetable gardens and greenhouses.

Age heterogeneity is also important for the exchange of information between individuals and serves the purpose of continuity in the population.

4.4. Sexual structure

Sexual structure– numerical ratio of males and females in different age groups populations. Characteristic of populations of dioecious individuals (expressed in the most clear form in arthropods and vertebrates) and dioecious plants, which in the temperate zone northern hemisphere are about 4%. Traditionally, the sexual structure of populations of seed plants is determined by the ratio of individuals with pistillate, staminate and bisexual flowers. The development program of pistillate and staminate flowers is quite complex. Flower sex is regulated by the concentration of auxins in plant roots, controlled by the level of genomic ploidy, as well as by a signal coming from the external environment. For example, in hemp (Cannabis sativa), in low light and lack of moisture, plants with bisexual flowers appear with a fairly high frequency.

Sex structure is dynamic and closely related to the age structure of the population and the living conditions of individuals. Primary sex ratio is determined during the formation of zygotes by genetic mechanisms based on the different quality of sex chromosomes (X- and Y-chromosomes) (Fig. 48). In mammals and many species of other animals, females are homogametic (XX set of sex chromosomes), and males are heterogametic (XY).

Rice. 48. Scheme of the genetic mechanism of sex determination using the example of gamete fusion in mammals (from I.A. Shilov, 1997)

In birds and butterflies, on the contrary, the heterogametic sex is represented by females, and males are homogametic. During the process of meiosis, it is possible different combinations sex chromosomes obtained from different parents, which determines the sex of each individual in the offspring. In this case, there is usually an equal sex ratio (1:1). The only representatives of mammals in whose populations there is a genetically determined excess of females are the forest lemming (Myopus schisticolor) and the hoofed lemming (Dicrostonyx torquatus). In these species, in addition to the wild-type X chromosome (X 0), there is a mutant chromosome that induces the development of individuals with the XY karyotype women's path. These females are widespread in populations and are fertile.

However, during the development process, the potential capabilities of the fetus are disrupted by various reasons, and at birth the actual ratio of male and female individuals turns out to be different. This ratio among newborns and juveniles is secondary sex ratio. The mechanism of sex redetermination under the influence of environmental factors, physiological causes, different mortality rates of fetuses of different sexes, which are superimposed on genetic conditioning, is especially pronounced at the embryonic and larval stages of ontogenesis. Thus, in many species of reptiles, the temperature of egg incubation is of leading importance for the formation of sex. In crocodiles, an equal number of males and females appear when the temperature in the nest is 32–33 °C. At lower temperatures (below 31 °C) only females develop, at higher temperatures (above 33.5 °C) only males develop. In the sea worm (Bonellia viridis), the larvae that float freely in the water become females. The larvae, which attach on the 4-6th day of development to the proboscis of an adult female and are influenced by the substances she secretes, develop into males.

Changes in the number of male and female individuals also occur during the ontogeny of individuals in the population. As a result, a new pattern emerges among adult individuals in the population. tertiary sex ratio, which is determined by various reasons. It may be the result of differential mortality of males and females. Due to the increased mortality of male bison in Belovezhskaya Pushcha, since 1983, there has been a tendency for the number of sexually mature males to decrease. The sex ratio is 1:1.6, and among adults it is 1:2.3. There are more males in populations of rare (endangered) birds. Females often die in nests during incubation. Stress, big physical activity shorten their life expectancy.

The sex ratio also depends on the developmental characteristics of the species. For example, the polychaete (Ophryotrocha puerilis) and the gastropod (Crepidula plana) are males at the beginning of puberty with small body sizes, and as their sizes increase, they begin to produce eggs. In some fish species, young individuals function as males and older individuals function as females. An ecologically complex population structure in some species is achieved due to the presence of dwarf forms in the population along with individuals of normal size. Among the kunja (Salvelinus leucomaenis), dwarf males do not make the usual migration to the sea for other individuals. Reproduction occurs at a young age. After reproduction, individuals do not die, but develop further like ordinary juveniles (Yablokov, 1987).

Ecological and cenotic conditions, especially trophicity and soil moisture, play a major role in determining sex in dioecious plants. Males dominate more often in extreme conditions with a low level of vitality, which is noted in coenopopulations of sorrel (Rumex acetosella) and other herbaceous species. Females are more demanding of soil richness. They prevailed and were noticeably higher, according to our data, on rich fresh soils in coenopopulations of stinging nettle. In some coenopopulations, female and male individuals form two canopies. The ratio of male to female Marchantia polymorpha depends on the degree of moisture. With increasing humidity, the proportion of males increases noticeably.

Sex ratios vary widely among species. In many mammals and fish, the tertiary ratio is 1:1, in humans the secondary ratio is 1:1, but with age it shifts towards women due to their longer duration life. The secondary sex ratio in penguin populations is 1:1, tertiary - 1:2. U gray monitor lizard for every 65 males there are 22 females. An excess of females is observed in lemming populations. U bats after wintering, the proportion of females sometimes decreases to 20%, and in some birds (pheasants, great tits) higher mortality is typical for males. According to F.S. Kokhmanyuk, in 1976, females predominated in the Minsk, Grodno and Armavir populations of the Colorado potato beetle (over 90%); in Gomel, Brest and Sochi - males (70–91%). The following year, the sex ratio in the Grodno population of the species was 1:1.

Populations exhibit an individual tendency for changes in the sex ratio. This phenomenon, very dynamic and multifactorial, leads to a more complex population structure. Each population is characterized not only by a certain numerical ratio of male and female individuals in different age structures, but also by the proportion different types males and females, the proportion of sterile individuals, as well as individuals with different sets of sex chromosomes (Yablokov, 1987). The sex ratio determines the intensity of reproduction and the overall biological potential of the population (Shilov, 1997).

V.N. Bolypakov and B.S. Kubantsev, summarizing the material on the characteristics of the sexual structure of animals, distinguishes four types of dynamics of the sexual structure of the population.

Unstable sex composition characteristic of animals with a short life cycle, high fertility and mortality (among mammals it is characteristic of species of the order insectivores). Sex ratios (secondary and tertiary) change frequently in different habitats and over relatively short periods of time.

Male-dominated composition characteristic of predatory animals with a pronounced form of care for offspring, whose populations do not reach high densities.

Female-dominated composition observed in such animals, the males of which have a shorter life expectancy and unfavorable conditions partially die off. The life of females is longer, fertility is low (ungulates, pinnipeds).

Composition with relatively equal numbers of males and females characteristic of highly specialized animals, often with high fertility (muskrat, mole, beaver, etc.).

Biological diversity of male and female individuals. Nature has taken the path of separating the sexes, allowing, as Schwartz (1980) puts it, amazing extravagance, dividing individuals of the species into two genetically different groups (males and females). Physiological differences lead to ecological diversity, which is a guarantee of maintaining population heterogeneity, especially in extremely unfavorable environmental conditions.

The biological diversity of male and female individuals is manifested in the degree of resistance to environmental factors, growth characteristics, timing of puberty, behavioral reactions, and lifestyle. Female plants are distinguished by their larger size, length of shoots, size and shape of leaves, crown structure, better development of root systems, higher regenerative capacity, as well as greater demands on the richness of the soil and its water regime. Due to the greater degree of water content in the tissues, they are more mesophilic organisms. Male individuals are characterized by greater drought resistance, sensitivity to the adverse effects of low temperature, infection, toxic substance. Sex differences in animals have even been identified in relation to the accumulation of heavy metals, for example in male swimming beetles (Dytiscus marginalis). Individual species have differences in nutrition, which reduces intraspecific competition. Thus, female mosquitoes (family Culicidae) are blood-sucking, and males either do not feed at all or feed only on dew or nectar. The unequal beak length of males and females of some birds allows individuals of the species to feed on different insects, and different shape beaks simplifies the joint extraction of insects from under the bark.

M.G. Popov (1983) believed that the sexual process does not have the primary goal of reproduction and is characteristic of highly organized creatures, but even they, for example insects, can develop without fertilization. Popov considered it a “permanent apparatus of variability” that ensures adaptation.

RUDN Journal of Agronomy and Animal Industries Bulletin of RUDN. Series: AGRONOMY AND ANIMAL HUSBANDRY

2017 Vol. 12 No. 1 66-75

http://journals.rudn.ru/agronomy

DOI: 10.22363/2312-797Х-2017-12-1-66-75

AGE SPECTRUM OF CENOPOPULATIONS

AS AN INDICATOR OF A SPECIES STRATEGY UNDER CONDITIONS OF ANTHROPOGENIC STRESS (using the example of rare and protected species of the Bitsevsky Forest natural and historical park)

I.I. Istomina, M.E. Pavlova, A.A. Terekhin

Peoples' Friendship University of Russia st. Miklouho-Maklaya, 8/2, Moscow, Russia, 117198

The authors of the article conducted a study of the structure of populations of rare and protected species included in the Red Book of Moscow and the Moscow Region, in connection with the influence on them of increasing anthropogenic pressure in the forest park belt of the city of Moscow. For the first time in the Bitsevsky Forest Park, based on the characteristics of ontomorphogenesis of such species as European undergrowth (Sanícula europaea L.), May lily of the valley (Convallaria majalis L.), polygonatum mul-tflorum (L.) All., intermediate corydalis (Coridalis intermedia (L.) Merat), the age composition of their coenopopulations is described and analyzed. By comparing the structure of coenopopulations of protected species, the authors showed the existence of different strategies of these species under conditions of anthropogenic stress.

Keywords: anthropogenic stress, species strategy, May lily of the valley, multifloral kupena, European undergrowth, intermediate corydalis, rare species, ontogeny, coenopopulation, age structure of coenopopulation, age spectrum

Introduction. A distinctive feature of Moscow from other large cities is the presence of relatively well-preserved massifs natural forests in the park part of the city. These urban forest parks contain a considerable number of forest plant species, among which there are rare and endangered species that need protection. Based on the state of populations of rare or declining species, one can judge the degree of recreational pressure on the forest park environment and formulate requirements for the conditions of protection of these species and the community as a whole.

In conditions large city indicators of such environmental factors as light, humidity, soil composition and drainage are clearly far from ideal for plants. For example, due to smoke, the lighting characteristics in Moscow are 10-20% lower than in the Moscow region. In this regard, the growth rate of trees decreases, herbaceous plants change the number and structure of populations. These indicators are also affected by the lack of natural soil cover in the city.

Ecological-coenotic strategies of species (type of behavior) are the most generalized and informative characteristic of a species, which allows us to explain its response to stress caused by abiotic and biotic factors, disturbances and, as a result, its place in plant communities.

Determining species strategies reveals plant behavior in a plant community. For a species, this characteristic is not constant; it can change from ecological optimum to pessimum, as well as from the center of the range to its periphery. For rare species, strategy analysis is an additional method that can be used to develop various compensatory programs for the implementation of their basic strategies for their protection. L.G. Ramensky in 1935 and P. Grime in 1979 independently described a system of strategy types that reflects the response of plant species to the favorableness of environmental conditions and the intensity of disturbances. Three primary types of strategies, called violents (competitors), patients (tolerants) and explerents (ruderals), are interconnected by transitional secondary strategies. Species have the property of plasticity of strategies, which allows them, depending on environmental conditions, to exhibit the properties of competition or tolerance.

In recent years, an ontogenetic approach has been used in assessing ecological and phytocoenotic strategies.

An important characteristic of plant populations is the ontogenetic spectrum, since it is associated with the biological properties of the species. When constructing the ontogenetic spectra of model species, we relied on ideas about the main stages of ontogenesis and the basic types of spectra.

The purpose of the study is to study the characteristics of the age structure of the price-populations of some rare and protected species of the natural-historical park "Bitsevsky Forest" as an indicator of the species' behavior strategy under conditions of anthropogenic pressure of varying degrees.

Objects and research methods. On the territory of the floristically rich Bitsevsky Forest Park, May lily of the valley (Convallaria majalis L.) is a widespread (both in the past and in the present) local forest species. In the same place, but much less frequently, you can find polygonatum multiflorum (L.) All., European undergrowth (Sanicula europaea L.) and intermediate corydalis (Coridalis intermedia (L.) Merat) - perennial herbaceous species characteristic of nemoral forests and growing in broad-leaved phytocenoses of the park in small cenopopulation loci.

All model species are included in the group of vulnerable species (category 3), that is, species whose numbers in Moscow under the influence of specific factors of the urban environment can significantly decrease in a short period of time.

The objectives of the study included a description of the age structure of populations of the above-mentioned species and a comparative analysis of their biological characteristics,

making it possible to determine the strategy of the species under conditions of anthropogenic stress.

The research was carried out from May 2011 to August 2016 in the Bitsevsky Forest natural and historical park.

The Bitsevsky Forest Natural Park has been a protected area since 1992 and, as an object of natural, historical and cultural heritage, serves to preserve biodiversity and maintain the species represented in it in a state close to natural; restoration of biogeocenoses disturbed as a result of anthropogenic influences, which include the proximity of residential areas, the influence of road transport, atmospheric emissions from thermal power plants and other enterprises, etc. Frequent visits to the park by surrounding residents inevitably leads to changes in the structure of both phytocenoses as a whole and individual populations of plant species.

The study of the structure of cenopopulations of protected species of broad-leaved phytocenoses of the Bitsevsky Forest Park is of considerable interest in connection with the tightening anthropogenic pressure experienced by all representatives of the flora, but especially rare and decorative types with large inflorescences and attractive flowers, such as those of the May lily of the valley and Kupena multiflorum.

To identify and describe individual stages of ontogenesis of the studied species, criteria for age states for herbaceous plants, described in detail in many sources, were used.

The work used the criteria widely used for studying plant ontogeny, and the method of census plots to study the age structure of coenopopulations. Individual stages of ontogenesis of the above-mentioned species were identified and analyzed, and individuals of different age states were counted on trial plots and age spectra were compiled for the cenopopulation as a whole.

The conclusions of the study were based on the fact that the response of plants to external influences, both natural and anthropogenic, manifests itself in changes in the growth pattern of individuals, their life and age state, which directly affects the change in the strategy of the species.

Results and discussion. When calculating the age composition of cenopopulations of the May lily of the valley (Convallaria majalis L.) in the Bitsevsky forest, it turned out that the cenopopulations were dominated by virginal partial shoots developing from a branched, long rhizome. Seedlings and juveniles are absent. This is evidence of suppressed seed regeneration, although the presence of a small number of immature shoots reflects the presence of vegetative propagation of the coenopopulation. A sufficient number of generative shoots indicates good prospects for seed propagation, but, unfortunately, these potentials are not realized by the species due to constant anthropogenic pressure (Fig. 1).

age conditions Fig. 1. Age composition of the cenopopulation of May lily of the valley in the Bitsevsky forest park

Thus, under the influence of recreational load, the age spectrum of lily of the valley cenopopulations has been modified in comparison with the basic spectrum: the number of young age individuals has significantly decreased, seed regeneration is practically absent, underdeveloped virginile and generative individuals predominate, and the number of growing rhizomes is decreasing. In addition, the growth rate and the proportion of flowering shoots decrease, so the dynamics of lily of the valley flowering gradually change - the breaks between years of mass flowering become longer, i.e. The cenopopulation of the May lily of the valley becomes regressive.

Under optimal conditions, the May lily of the valley is a competitive-tolerant vegetatively mobile species. But in the conditions of the Bitsevsky forest park, under the influence of the anthropogenic factor, the systemic organization of lily of the valley coenopopulations is disrupted, which is the most important condition for their stability.

May lily of the valley forms incomplete coenopopulations, with a predominance of virginal individuals, characterized by reduced vitality of above-ground partial shoots, low density of thickets, and low seed productivity. But even in this situation this type Due to vegetative mobility, it can retain the occupied territory for a sufficiently long time, thereby coping with anthropogenic pressure. This position of the May lily of the valley in the Bitsevsky forest park indicates that the strategy of this species belongs to the group of stress-tolerants. The ontogenetic strategy of the studied species is to reduce the number of seed-bearing individuals and increase the number of individuals of vegetative origin, delaying the transition of individuals to the generative state for as long as possible.

A perennial herbaceous short-rhizomatous polycarpic species - polygonum multiflorum (Polygonatum multiflorum (L.) All.) - forms coenopopulations where the center of influence on the environment is the individual. The study of some aspects of reproductive biology and the identification of the life strategy of Polygonatum multiflorum characterizes this species as easily vulnerable, capable of living

in rather narrow environmental conditions. Due to the biological characteristics of seed propagation, reproduction of kupena in nature occurs quite slowly, which requires special attention to the conservation of this species.

Due to the disturbance of natural habitats and the increasing popularity as a beautiful flowering plant, the multifloral plant is being intensively exterminated, especially in forested areas of cities, so there is a real threat of a decline in the number of this species. In Bitsevsky Park, this species exists in separate small, weakly diffuse coenopopulation loci, the age composition of which was carefully calculated. The location of coenopopulation loci of the kupena in the territory of Bitsevsky Park is scattered, which can be explained by the introduction of seeds with the help of birds and their random establishment. In all cases, the multifloral kupena is found only in oak-linden phytocenoses Bitsevsky forest, surrounded by broad grass.

The age structure of the cenopopulation loci of Kupena multiflorum is almost complete, mainly virginal and generative individuals predominate, which is most likely due to the dominance of vegetative propagation of Kupena multiflorum over seed (Fig. 2). The presence of almost all ontogenetic states in the age spectrum of the kupena indicates the dynamic stability of the coenopopulation of this species in the studied community.

Rice. 2. Age composition of the coenopopulation and kupena multiflora in the Bitsevsky forest park

Thus, the coenopopulation of Kupena multiflorum can be characterized as normal, complete. The predominance of virginal and young generative individuals is a sign of the prospects for the development of these cenopopulation loci in the foreseeable future. Thus, as a rare species belonging to the 3rd category, Kupena multiflorum is doing relatively well in the Bitsevsky Forest Park.

Based on the structure of the cenopopulation of Kupena and the contribution of individual ontogenetic stages, we can define Kupena multiflorum as a species characterized by a competitive-tolerant type of life strategy with elements of stress-tolerance.

European undergrowth (Sanicula europaea L.) - pre-glacial relict, mesophyte, grows in broad-leaved, mixed and less commonly coniferous forests, reproduces mainly by seeds. This protected species is found on the territory of the Bitsevsky Forest Park in the form of small coenopopulation loci, which are located mainly along the path network, which is explained by the specific reproduction of the undergrowth (exozoochory). The spherical parts of its fractional fruit (3.5-4.5 mm in length and almost the same width) - mericarps - are covered with small hooked spines. The undergrowth is well regenerated by seeds, since seedlings, juvenile plants and immature individuals are found in almost all studied cenopopulation loci of this species. The undergrowth germinates above ground, in places with disturbed soil cover and undeveloped litter, free from other plants. The age spectra of the undergrowth in the broad-leaved phytocenoses of the Bitsevsky forest are almost complete spectra with a maximum on immature individuals.

A shift to the left indicates the youth of the undergrowth coenopopulation loci. In population loci located closer to forest roads, subsenile and senile individuals appear in lighter areas (Fig. 3).

Rice. 3. Age spectrum of European undergrowth in the Bitsevsky forest park

The general age spectrum of the undergrowth population (Fig. 3) shows that the age structure of populations of this species is left-sided, it is dominated by individuals of pregenerative stages, namely immature, juvenile and seedlings. This coenopopulation structure is characteristic of species prone to the r-strategy, ruderals (explerents). And, indeed, in the observed coenopopulations of the undergrowth, seedlings, juvenile and immature plants grew in the most disturbed places of the herbaceous layer - molehills, mouse holes, bare areas of soil.

Thus, the presence of all age states in the spectrum of the undergrowth indicates its stability, and the predominance of young stages of ontogenesis indicates the prospects for the development of these coenopopulation loci in the foreseeable future. That is, as a rare species belonging to the 3rd category, the European undergrowth experiences relatively weak anthropogenic pressure in the Bitsevsky Forest Park. The stability of the population of this species is ensured by its r-strategy and its association with disturbed habitats. The strategic weakness of the undergrowth in the Bitsevsky forest park is manifested in the fact that it cannot compete with stronger ruderal species, and in this case it can be classified as a stress-ruderal type of secondary transition strategy. Under optimal ecological and cenotic conditions, this species can be classified as a competitive ruderal species.

Corydalis intermedia, or medium (Corydalis intermedia (L.) Merat), is a perennial polycarpic herbaceous plant 8-15 cm high, belongs to the group of spring ephemeroids and belongs to the category of “rare” species in Moscow.

This species reproduces by seed; vegetative propagation is almost completely absent.

In the generalized age spectrum of the intermediate corydalis population, two maximum numbers are observed: in the young part of the spectrum (seedlings are immature individuals) and for generative individuals, i.e. it can be classified as a normal, complete type of population (Fig. 4). The presence of individuals of all age conditions in the age spectrum indicates the stability and prosperity of the population of this species. The age spectrum of this species is complete with a slight shift towards young individuals. The maximum in the generative part of the spectrum indicates that individuals of the intermediate corydalis remain in this state for a long part of the life cycle. The increase in the number of individuals in the senile part of the spectrum is explained by the senile particulation found in corydalis.

p \ 1t V d z age states

Rice. 4. Age spectrum of the intermediate corydalis in the Bitsevsky forest park

These characteristics of the age structure of the corydalis intermediate coenopopulation allow us to conclude that in the studied habitat of the Bitsevsky Forest Park there are quite good conditions for the existence of this species. The coenopopulation of Corydalis intermedia, despite the dense path network in this place, is thriving and has optimal density, and is also growing, since its area has increased by several square meters over the past ten years. In the phytocenosis, Corydalis intermedius exists only in the synusia of ephemeroids, and in this synusia the type of its behavioral strategy can be classified as competitive-tolerant.

Based on the above, when comparing the age structure of cenopopulations of four protected species, one can see their different responses to anthropogenic pressure, which can be explained various types behavior strategies of these species under stress.

Under the influence of recreational pressure and anthropogenic pressure, the age spectrum of cenopopulations of Lily of the valley is modified, the state of the multifloral plant is stabilized, the number of young population loci of European undergrowth increases, and the cenopopulation of Intermediate corydalis practically does not respond to it. These changes are associated with different types of behavioral strategies of these species in the phytocenosis.

Corydalis intermedius turns out to be a rather strong competitive-tolerant species among ephemeroids; its coenopopulation locus increases, despite the growth and compaction of the path network.

As a result of its ruderal strategy, the undergrowth occupies new habitats, possibly losing old ones. Kupena retains small population loci as a result of tolerant behavior, reacting little to changes in anthropogenic load. And lily of the valley moves from a competitive strategy under the influence of anthropogenic stress to stress-tolerant behavior.

Thus, taking into account these features and subject to certain protection measures, sometimes very minor, related only to environmental education, it is possible not only to preserve, but also to increase the number of these species in the natural-historical park “Bitsevsky Forest”.

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DOI: 10.22363/2312-797X-2017-12-1-66-75

ONTOGENIC SPECTRUM OF COENOPOPULATIONS AS INDICATOR OF SPECIES STRATEGY

UNDER ANTHROPOGENIC STRESS (on the example rare and protected plants of the natural and historical park "Bitsevsky forest")

I.I. Istomina, M.E. Pavlova, A.A. Terechin

Peoples" Friendship University of Russia (RUDN University)

Miklukho-Maklaya st., 6, Moscow, Russia, 117198

Abstract. The authors investigated the structure of populations of rare and protected species included in the Red book of Moscow and Moscow region, in connection with the influence of increasing anthropogenic loads in the forest zone of the city of Moscow. For the first time in the Bitsa forest Park based on the features of ontomorphogenesis of species such as the Sanicula europaea L., Convallaria majalis L., Polygonatum multiflorum (L.) All., Coridalis intermedia (L.) Merat. described and analyzed the age structure of their populations. Comparing the structure of populations of protected species, the authors showed the existence of different strategies of these species under conditions of anthropogenic stress.

Key words: anthropogenic stress, strategy type, Sanicula europaea L., Convallaria majalis L., Polygonatum multiflorum (L.) All., Coridalis intermedia (L.) Merat., a rare species, ontogenesis, coeno-population, age structure of the cenopopulation, age range

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2. Ramenskiy L.G. Introduction to complex soil-geobotanical investigation of lands. Moscow, Selkhozgiz, 1938.

3. Coenopopulations of plants: Basic concepts and structure. Moscow: Nauka, 1976.

4. Coenopopulations of plants (essays on population biology). Moscow: Nauka, 1988.

5. Smirnova O.V. The Structure of the herbaceous cover of broad-leaved forests. Moscow: Nauka, 1987.

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9. Polyakova A.G., Gutnikov V.A. Parks: Ecology and floristic characteristics. Moscow: GEOS, 2000.

10. Zaugolnova L.B. Structure of populations of seed plants and the problems of their monitoring: author. dis. ... Dr. biol. sciences. St. Petersburg, 1994.

11. Pianka E.R. On r- and K-Selection. The American Naturalist. 1970. Vol. 104. N 940. P. 592-597.

Age spectrum. Modern problems of science and education

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