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with the dose rate, there is not such a correlation in the samples from the Sosnovy Bor region.

Aberrant cells, %

5

4

3

2

1

4

5

6

1

2

3

1

2

3

1

2

3

1

2

3

0

1995

1997

1998

1999

2000

Fig. 5. Aberrant cell frequency within root meristem of Pinus sylvestris L. seedlings in 1995-200. Experimental sites in the Sosnovy Bor region - 1, 2, and 3, in the 30-km zone of the Chernobyl NPP –4, 5, and 6.

The revealed fact obliged us to make a more careful examination of these experimental data. The analysis of the structural mutations spectrum [15] has shown presence in the Sosnovy Bor data and absence in all control and Chernobyl variants of tripolar mitoses, a rather rare type of cytogenetic alterations, which appearance possibly links to spindle damage [16]. It was shown in [17] that an increase in the yield of tripolar mitoses in Syringa vulgaris L. and Armeniaca vulgaris Lam. was associated with the contamination of the local soils with a heavy metal mixture. From this, together with the dosimetric data, a considerable contribution of genotoxic chemicals to the environmental contamination in the Sosnovy Bor region may be supposed, but not as opposed to the 30-km ChNPP zone.

Now, when an anthropogenous impact to biota has become one of the most significant ecological factors, it is pertinent to consider the adaptive potentials of natural populations. One consequence of chronic irradiation of natural populations is an apparent increase in the mean radioresistance - the so-called “radio-adaptation phenomenon”; this has been observed by studies in the East Urals trail region [18, 19] and can be revealed by exposure of seeds to an additional, acute ϑ-radiation. It was shown later [19, 20] that the population divergence by radioresistance is connected to the selection for changes in the effectiveness of the reparative system and is not accompanied by visible morphologic alterations.

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Aberrant cells, %

3.0

2.0

1.0

1		2	3	4					2	3	4				4
					1							1	2	3
0.0
		1998							1999				2000

Fig. 6. Aberrant cell frequency in intercalar meristem of needles of Pinus sylvestris L. in 1998-2000. 1, 2, 3, 4 – experimental sites in the Sosnovy Bor region.

Aberrant cells, %

8

4

							3		1			3
1										2
		2
0
		1999								2000

Fig. 7. Aberrant cell frequency in seedling root meristem of Pinus sylvestris L. exposed to acute ϑ-irradiation of 15 Gy in 1999 and 2000. 1, 2, 3 - experimental sites in the Sosnovy Bor region.

A part of the seeds collected in the Sosnovy Bor region in 1999-2000 has been subjected to an acute ϑ-ray exposure. The seeds from the Scotch pine populations growing in the town of Sosnovy Bor and at the 'Radon' LWPE site appear to be significantly more resistant to the acute ϑ-radiation than the controls (Fig. 7). Notice, a number of pine generations replaced during the existence of the ‘Radon’ LWPE and the Leningrad NPP, unlike the East-Ural radioactive trial, is obviously insufficient for natural selection on repair systems efficiency in its classical

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meaning. There are different explanations of the phenomenon regarded to a selection against radiosensitive cells [21] as well as an inheritable change of spectrum of functionally active genes [19]. But, in any case, the findings show that there are processes of cytogenetic adaptation in the examined populations that can be revealed by an additive acute ϑ-radiation of seeds.

6. Conclusion

It follows from the presented results that models, being used now for the estimation of biological effects of low-level radiation and combined effects of low doses and concentrations of factors of different nature, are founded on the linear nothreshold concept. A hypothesis on additivity of effects, allowing even extrapolation , has no strong biological substantiation and is in contradiction with available experimental data. The regularities in the formation of cytogenetic effects of low doses are characterised by vital non-linearity and have a universal character, differing for various objects in dose values at which there are changes of the dependency character. Chronic exposure at doses above a certain value can be an ecological factor altering the genetic structure of a population. The further development of this problem should result in a determination of levels of biological organisation, test-objects and test-systems which can become a basis for ecologically substantiated estimates of biological consequences for biota and human from habitation in areas where radiation-dangerous objects are located or which experienced heavy radiation accidents.

7.References

1.G.N.Romanov, D.A.Spirin. Effect of ionizing radiation on living nature at the levels meeting requirements of the current derived levels. Proceedings of the USSR Academy of Sciences, 1991. V.318. pp. 248-251. (in Russian).

2.V.A.Shevchenko, V.L. Pechkurenkov, V.I. Abramov. Radiation genetics of natural populations. M., Nauka, 1992. 221 pp. (in Russian).

3.R.M.Alexakhin, S.A. Geras’kin, S.V. Fesenko. The accident at the Chernobyl nuclear power plant and the problem of estimating the consequences of radioactive contamination of natural and agricultural ecological systems. in: Proceedings of an international symposium on ionizing radiation. V. 2. Stockholm, 1996. 516-521 p.

4.S.A.Geras’kin, G.V.Koz’min. Estimation of effects of physical factors on natural and agricultural ecological systems. Russ.J.Ecology, 1995. ¹ 6. pp.419-423.

5.S.A.Geras’kin. Critical analysis of up-to-date conceptions and approaches to estimation of biological effect of low-level radiation. Radiat. Biol. Radioekol., 1995. V. 35. ¹ 5. pp. 563-571. (in Russian).

6.S.A.Geras’kin. Regularities of cytogenetic effects of low level ionizing radiation. Thesis. Obninsk, 1998. 50 pp. (in Russian).

7.S.A.Geras’kin, V.G.Dikarev and others. Regularities of cytogenetical disturbances induction by low doses of radiation in barley germ root meristem cells. Radiat. Biol. Radioekol., 1999. V. 39. ¹ 4. pp. 373-383. (in Russian).

8.S.A.Geras’kin. Concept of biological effect of low dose radiation on cells. Radiat. Biology. Radioecology, 1995. V. 35. ¹ 5. pp. 571-580. (in Russian).

9.T.I.Evseeva, S.A.Geras’kin. Separate and combined action of radiation and not radiation nature factors on Tradescantia. Ekaterinburg, Nauka Publishers, 2001. 156 pp. (in Russian).

10.S.A.Geras’kin, V.G.Dikarev and others. The combined effect of ionizing radiation and heavy metals on the frequency of chromosome aberrations in spring barley leaf meristem. Russ.J.Genetics, 1996. V. 32. ¹ 2. pp. 246-254.

11.T.I.Evseeva, S.A.Geras’kin, E.S. Khramova. Cytogenetic effects of separate and combined action of 232Th and Cd nitrates on Allium cepa root tip cells. Cytologia, 2001. V. 43. ¹ 8. pp.803-808. (in Russian).

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12.S.A.Geras’kin, V.G.Dikarev, N.S.Dikareva. The influence of combined radioactive and chemical (heavy metals, herbicide) contamination on cytogenetical disturbances occurrence in intercalar meristem of spring barley. Radiat. Biol. Radioekol., 2002. V. 42. ¹ 4. (in press) (in Russian).

13.V.G.Petin, G.P.Zhurakovskaya and others. Low doses and problems of synergistic interaction of environmental factors. Radiat. Biol. Radioekol., 1999. V. 39. ¹ 1. pp. 113-126. (in Russian).

14.S.A.Geras’kin, V.G.Dikarev and others. Cytogenetic consequences of chronic irradiation under low doses for agricultural crops. Radiat. Biol. Radioekol., 1998. V. 38. ¹ 3. pp. 367-374. (in Russian).

15.S.A.Geras’kin, L.M.Zimina and others. Bioindication-based comparison of anthropogenic pollution near a radioactive-waste processing facility and in the 30-km control area of the Chernobyl nuclear power plant. Russ. J. Ecology, 2000. ¹ 4. pp. 300-303.

16.I.B.Alieva, I.A.Vorobiev. Cell’s behavior and centrioles at multipolar mitosis induced by nocodasolum. Cytology, 1989. V. 31. ¹ 6. pp. 633-641. (in Russian).

17.V.P.Bessonova. The state of pollen as an indicator of the environmental pollution with heavy metals. Russ. J. Ecology, 1992. ¹ 4. pp. 45-50.

18.L.V.Cherezhanova, R.M.Alexakhin. On a biological effect of an increased ionising radiation background and the processes of radioadaptation in populations of herbaceous plants. Russ. J. General Biology, 1975. V. 36. ¹ 2. pp. 303-311. (in Russian).

19.V.A.Shevchenko, V.L.Pechkurenkov, V.I.Abramov. Radiation genetics of natural populations: genetic consequences of the Kyshtym accident. M., Nauka, 1992. 221 pp. (in Russian).

20.S.A.Sergeeva, A.B.Semov and others. Repair of radiation-induced damages to plants growing under conditions of chronic exposure to â-radiation. Radiobiologia, 1985. V. 25. ¹ 6. pp. 774-777. (in Russian).

21.V.A.Kal’chenko, I.S.Fedotov. Genetics effects of acute and chronic ionizing radiation on Pinus sylvestris L. inhabiting the Chernobyl’ meltdown area. Russ. J. Genetics, 2001. V. 37. ¹ 4. pp. 427447.

22.S.A.Geras’kin, B.I.Sarapul’tzev. Automatic classification of biological objects on the level of their radioresistence. Automat. Telemek., 1993. pp. 182-189. (in Russian).

ROLE OF VARIOUS COMPONENTS OF ECOSYSTEMS IN BIOGEOCHEMICAL MIGRATION OF POLLUTANTS OF ANTROPOGENIC ORIGIN IN FORESTS

A. ORLOV, V. KRASNOV

Polesskiy Branch of Ukrainian Scientific Research Institute of Forestry and Forest Amelioration (UkrSRIFA), pr. Mira, 38; Zhitomir, 10004, UKRAINE,

[e-mail]

1. Introduction

At present time the environment is contaminated by a complex of pollutants. After the Chernobyl catastrophe the main attention of researchers, especially in Europe, was paid to radioactive pollution of the environment and therefore such important problems as a contamination of various components of the ecosystem by heavy metals, pesticides etc. had become considered as a minor problem. It should be noted that today the complex evaluation of synergistic influence of pollutants of anthropogenic origin on wild species of biota as well as on man is almost absent. Such evaluation is very pressing now especially in the regions with relatively high levels of contamination of the environment but with concentrations below its permissible values.

One of the main criteria determining the position of certain biogeocenosis in a radioecological classification of forest types, is the ability of the phytocenosis of the given habitat to accumulate the main doseforming technogenic radionuclides (137Cs and 90Sr) with a certain intensity [11]. The analysis of the role of different layers of vegetation in the distribution of the total stock of 137Cs and its biological migration in forests is definite from a geochemical point of view because the vegetative cover can serve as the indicator of autorehabilitation of a forest landscape [3] as well as the index of the recovery of a qualitative and quantitative phytomass structure after radioactive contamination. Biological migration of 137Cs is considered as one of the key processes of redistribution of radionuclide in natural ecosystems [9], determining the possibility of their economic use after radioactive contamination.

In contrast to other types of vegetation, the layers of forest phytocenosis can increase their phytomass a hundred fold during the development of the latter (in particular, tree canopy) and also essentially change the intensity of 137Cs accumulation. In coordination with the development of the tree canopy and especially with closeness of tree crowns begins also the more or less quick development of undergrowth vegetation: undergrowth meaning juvenile tree canopy, grass–dwarf-shrub layer, moss and lichen layers, layer of macromycetes. It should be noticed that there is a close ecological correlation between vegetation and soil in each habitat [4]. The main physical and agrochemical soil parameters not only determine the intensity of radionuclides migration in a system «plant – soil», but also, in turn, essentially depend on the habitability of phytocenosis, which also essentially influences the radionuclides redistribution in the ecosystem [15]. For example, in forest ecosystems the significant part of activity of radionuclides annually returns to the soil with litterfall. Simultaneously radionuclides uptake by tree canopy, dwarf-shrubs and grass by rooted way is

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observed [10, 12]. The separate layers of forest vegetation are characterized by a very significant aerial sorption capacity in relation to certain radionuclides.,They do not have a rooted way of radioactive uptake.Examples are sphagnum mosses in forested bogs in ombrotrophic complexes [7], green mosses in pine forests of authomorphic landscapes or epigeous lichens in conditions of extremely poor and dry pine forests. By investigating the regularities of distribution of 137Cs activity in layers of a forest ecosystem we can obtain the basis for prognostic mathematical modeling of migration of 137Cs in forest ecosystems as well as the data for model validation.

2. Objects and methods

The researches were carried out in Central Polessye of Ukraine (Zhitomir region) in summer of 2000 on three experimental plots representing a certain type of forest biogeocenosis of pine woods. The selection of these experimental plots was conducted among 15 sites where main phytocenotic parameters were taken into account i.e. age of tree canopy, affinity of their species composition and cenotic structure, type of forest-growth conditions. Each experimental plot was described according to standard methods [14] and had the area of 1,0 ha.

Two experimental plots represented the extremes of the ecological conditions of forests of the region: first – a pine forest of cenosis Cladonio-Pinetum Jurassek 1927 in the poorest conditions of high dry sandy dunes. This floristic association belongs to Union Dicrano-Pinion Libb. 1933, Ordo Cladonio-Vaccinietalia K.-Lund 1967, Class

Vaccinio-Piceetea Br.-Bl. 1939. Second site represented forested bog complexes of cenosis Ledo-Sphagnetum magellanici Sukopp 1959 em. Neuhäusl 1969 belonging to Union Sphagnion magellanici Kästner et Flössner 1933 em Dierss. 1975, Ordo Sphagnetalia magellanici (Pawl. 1928) Moore (1964) 1968, Class OxycoccoSphagnetea Br.-Bl. et R.Tx. 1943. The third experimental plot represented pine forests of cenosis Molinio-Pinetum Mat. (1973) 1981, belonging to Union Dicrano-Pinion Libb. 1933, Ordo Vaccinio-Piceetalia Br.-Bl. 1939, Class Vaccinio-Piceetea Br.-Bl. 1939. Ecological conditions in the last habitat were close to the optimum for the growth of Pinus sylvestris L. in Ukrainian Polessye.

The ecosystem Cladonio-Pinetum was situated on the top of a sandy dune with relative altitude of about 9 m. The tree canopy consisted of Pinus sylvestris of 40 years old with a mean height of 4,2 m and a mean diameter of 7,3 cm. The layer of juvenile trees was rarefied consisting of Pinus sylvestris. The layer of undergrowth also was complex and consisted of Chamaecytisus ruthenicus (Fisch. ex Wo³.) Klaskova. Grass– dwarf-shrub layer was complex and had a total projective cover of 10-12%. Its basis was created by Corynephorus canescens (L.) P.Beauv (5-7%), Thymus serpyllum L. (1- 3%), Calluna vulgaris (L.) Hull (3-5%). The lichen layer was represented by two sublayers – epigeous and epiphytic. The sublayer of epigeous lichens was dense, with a total projective cover 85-90 % and a phytomass of about 0,2 kg/m2 of absolute dry weight. Its basis was created by Cladina arbuscula ssp. mitis (Sandst.) Ruoss (60-65 %), a smaller participation in the formation of this sublayer was characteristic for

Cladonia uncialis (L.) F.Weber ex F.H.Wigg. (10-15 %). The sublayer of epiphytic lichens mainly consisted of Hypogymnia physodes (L.) Nyl. On the driest and infringed dune sites fragments of moss cover from Polytrichum piliferum Hedw. (3-5 %) were observed. The layer of macromycetes was represented mainly by a symbiotic

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mushroom species - Lactarius rufus (Scop). Fr., Siullus variegatus (Fr). O.Kuntze, Boletus badius Fr., Paxillus involutus (Batsch.) Fr., smaller role in creation of this layer played saprotrophic species – Cantharellus cibarius Fr. and Tricholoma flavovirens (Pers. ex Fr.) Lund et Nannf.

The ecosystem Ledo-Sphagnetum magellanici was situated in a central part of a large ombrotrophic bog “Long Moss” with total squire about 500 ha. Mineral nutrition of mentioned above bog happens mainly from atmospheric precipitation. Pinus sylvestris of 40 years old with a mean height of 2,3 m and a mean diameter 7 cm formed a rarefied tree canopy with crown closeness of 0,2-0,3. Layers of undergrowth and juvenile trees were absent. Grass–dwarf-shrub layer had a total projective cover of 3040 % and mainly consisted of boreal bog species: Eriophorum vaginatum L. (20-25 %),

Vaccinium uliginosum L. (3-5 %), Ledum palustre L. (3-5 %), Oxycoccus palustris (L.) Pers (3-5 %), Andromeda polifolia L. (1-3 %). A moss layer with a total projective cover of 95-98 % mainly created by Sphagnum fallax (Klinggr.) Klinggr., and macromycetes layer – Suillus variegatus.

The ecosystem Molinio-Pinetum was situated on a plane habitat with soddypodzolic sandy-loam soils and an average annual depth of ground water level of about 1,3 m. The 45 years old tree canopy of Pinus sylvestris had a mean height of 23,5 m, with a mean diameter of 22 cm, and a small participation also of Betula pubescens Ehrh. Complex undergrowth with closeness up to 0,2 consisted of Frangula alnus Mill. Grass–dwarf-shrub layer was characterized by the total projective cover of 60-75%. Its basis was formed mainly by boreal dwarf-shrubs: Vaccinium myrtillus L. (50-60 %), V. vitis-idaea L. (5-10 %) and Calluna vulgaris L. (1-5 %). As an impurity also species such as Pteridium aquilinum (L.) Kuhn, Dryopteris carthusiana (Vill.) H.P.Fuchs, Molinia caerulea (L.) Moench. and Luzula pilosa L were met. The moss layer had a total projective cover of about 80-95 % and consisted of green mosses: Pleurozium schreberi (Brid). Mitt. (40-50 %) and Dicranum polysetum Sw. (30-45 %). The lichen layer was represented by sublayers of epiphytic species, mainly Hypogymnia physodes and Pseudoevernia furfuracea. The layer of macromycetes was characterized by a rich species composition, including more than 20 species. The most typical among them were Paxillus involutus, Lactarius rufus and Russula paludosa (L.) Kuntze, fruitbodies of these species also created the basis of total mushrooms fruitbodies biomass in the analyzed forest ecosystem.

For the determination of the distribution of 137Cs activity in ecosystems on experimental plots it was necessary to calculate the weight characteristics of each of its components per unit of the area, and also the specific activity of radionuclide in last ones. For the determination of the main characteristics of tree canopy research was carried out according to standard methods including full account of trees on the area of 1,0 ha [1]. After this procedure the parameters of a mean model tree were calculated for three main stages of trunk thickness. Three model trees were cut down on each experimental plot, each of the model tree represented a certain stage of a trunk thickness. Phytomass of each model tree was divided into separate organs and tissues, which were weighed for fresh weight, and also samples for the further analyses were taken from them. Branches were arranged according to diameter from thin (diameter < 5 mm) to thick (> 5 mm) [6]. The samples from each tree were taken proportionally to their weight from tree crown parts: upper, mean and lower and were further integrated in one sample for each model tree. The trunk was sawn in 1-m sections, from which bark was removed.

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Wood and bark were weighed separately. The sample of trunk wood for the analysis was taken from the fixed height of 1,3 m. One integrated sample of needles from branches of a different part of tree crown was taken from each of the model tree, proportional to their weight in crown; samples of annual shoots were also taken similarly. The mass of the thin roots (diameter < 2 mm) and thick roots (> 2 mm) from one model tree was determined according the to literature data [6]. Samples of roots for the analysis of each model tree were collected uniformly on parts of their soil horizon. For research of abovegrowth and undergrowth phytomass of grass–dwarf-shrub layer investigations were conducted in 5 fold on sites with an area of 25 m2 each. Total digging of these species were carried out with the consequent division in aboveground and underground phytomass. The roots of vascular plants were washed from soil particles in laboratory. The investigations of epigeous lichens were carried out in 5 fold on sites of 1,0 m2, and macromycetes on the area 100 m2. Biomass of the macromycetes layer as a whole was calculated as the sum of mass of its fruitbodies sampled on experimental plot and mass of the mushroom mycelium which was accepted as 0,12 kg·m-2 according to the literature data for similar ecosystem Molinio-Pinetum [17]; it was also accepted that the 137Cs specific activity in mushroom fruitbodies and mycelium was identical [18]. Epiphytic lichens were sampled with the divisionper species from model trees before their cutting. The layer of green mosses was studied on experimental plots in automorphic conditions in 5 fold on sites of 500 cm2 each and layer of sphagnum mosses in hydromorphic conditions – on an area of 2500 cm2 . It is important that sphagnum mosses were divided into living parts, dead parts and peat litter, which were weighted and analyzed separately.

The structure of genetic horizons in the three soil profiles was studied on each experimental plot in automorphic landscapes. Separate fractions of forest litter (contemporary, semi-decomposed and decomposed) as well as mineral soil samples were taken from each profile from fixed surface of 500 cm2; the thickness of mineral soil samples was equal to 2 cm and the investigation were carried out up to 30 cm depth. In hydromorphic conditions samples of uninfringed peat were taken after deleting rather thick layers of sphagnum mosses and peat litter, with the help of special turf Giller’s core with a diameter of 5 cm; on depth up to 30 cm, peat was divided in 5- cm layers in which the measurement of 137Cs content was carried out separately. In our research the part of soil retaining 137Cs activity was calculated by a computational method and was equaled to a difference of activity of a radionuclide in soil together with fungi mycelium (was determined by results of sampling) and activity deposited in mycelium (was determined by a computational method [17, 18]).

All samples were dried up to air-dry weight during 72 hours at the temperature of 80 0C, for all fractions of phytocenosis the recalculation from fresh into air-dried weight was carried out. The dried samples of vegetation and soil were milled and placed in Marinelli’s beaker of 1000 cm3 or smaller cylindrical volumes (75 and 135 cm3). The measurement of 137Cs specific activity in samples was carried out in a spectrometer LP4900B «ÀFORA» with GeLi-detector. The relative error of measurement of 137Cs specific activity in samples varied in the limits of 10-20% depending on their activity.

In this research we have made the attempt to evaluate the distribution of some pollutants of antropogenic origin proceeding from assumption that 137Cs concentration is the most easily measured one. The first step was the calculation of distribution of weight of forest ecosystem components; the second step was the

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evaluation of the role of each component in the forest ecosystem in the redistribution of total activity of this radionuclide and selection of key components in this process; the third step was the study of the concentrations of the main heavy metals-pollutants of environment in the selected key components and its comparison with analogues indexes in other ecosystem components. The statistical data processing was made with use of the software package «Statgraphics».

3. Results and discussion

Biogeocenotic research has allowed to describe the distribution of 137Cs specific activity as well as the mass of each of ecosystem component per unit area (1,0 ha). The above mentioned components in each ecosystem were combined in two macroblocks i.e. soil together with forest litter and mycelium of mushrooms and in remaining components. The part of 137Cs retained by separate component at first was calculated within the limits of mentioned above macroblocks, and was recalculated then on the ecosystem as a whole (tables 1, 2, 3).

The data in the above mentioned tables 1, 2, 3 illustrate some important features: significant interspecific differences of 137Cs accumulation by species of the same layer of vegetation in each investigated ecosystem; an exponential decrease of 137Cs specific activity in soil with increasing depth; close dependence of total activity of 137Cs in the specific layer on its biomass and also on intensity of radionuclide accumulation by the root or non-root way.

From generalizing the data of the above mentioned tables it is correct to draw the conclusion that in components of ecosystem the total activity of 137Cs is nonuniformly distributed. In forested bog of ombrotrophic ecosystem Ledo-Sphagnetum magellanici the leading geochemical role in migration of 137Cs is played by the layer of sphagnum mosses which retained 84,75 % of total activity of radionuclide of phytocenosis. A significantly smaller role is played by the grass–dwarf-shrub layer (9,61 %) and the tree canopy (4,79 %). The calculated contribution of mushroom mycelium to the total activity in the 30-cm stratum of peat was equal to 33,67%. In the ecosystem Cladonio-Pinetum the main geochemical role in biological migration of 137Cs is played by the tree canopy containing 50,56 % of the total activity of this radionuclide of phytocenosis and also by the layer of epigeous lichens (43,56 %). The contribution of mushrooms mycelium into the total activity of the soil with forest litter was equal to 24,98%.

In the ecosystem Molinio-Pinetum the role of tree canopy and moss layer in radionuclide retaining was comparable – 49,93 % and 46,55 % accordingly. The part of the mycelium of mushrooms in total 137Cs activity of the soil together with forest litter in this cenosis is sharply increased, i.e. up to 58,99 % in comparison with the former ecosystems.

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Table 1. Distribution of 137Cs activity in forested bog ecosystem of Ledo-Sphagnetum magellanici, density of ground deposition of 137 kBq·m-2 (0,41 Ci·km-2 )

Ecosystem component	Mass, kg·ha-1	137Cs specific	137Cs activity,	Part of 137Cs total activity,
		activity, Bq·kg-1	MBq·ha-1	%
Tree canopy	3480	–	5,798	4,79
Wood	1160	1260	1,462	1,21
Bark	480	2450	1,176	0,97
Needles	320	2720	0,870	0,72
Branches	260	2560	0,666	0,55
Roots	560	2900	1,624	1,34
Layer of epiphytic lichens	0,25	7800	0,002	0,001
Grass–dwarf-shrub layer	2050,5	–	11,659	9,614
Oxycoccus palustris	50	8400	0,420	0,35
(aboveground phytomass)
(underground phytomass)	0,5	10000	0,005	0,004
Ledum palustre	100	7800	0,780	0,64
(aboveground phytomass)
(underground phytomass)	130	9800	1,274	1,05
Eriophorum vaginatum	900	4400	3,960	3,27
(aboveground phytomass)
(underground phytomass)	870	6000	5,220	4,30
Layer of Macromycetes	0,7	800000	0,560	0,46
(fruitbodies)
Moss layer	9000	–	103,250	84,75
Sphagnum, alive part	3000	16100	48,300	39,83
Sphagnum, dead part	3500	11700	40,950	33,77
Peat litter	2500	5600	14,000	11,55