{"id":5000,"date":"2022-04-18T17:01:28","date_gmt":"2022-04-18T14:01:28","guid":{"rendered":"https:\/\/jfsi.ru\/?p=5000"},"modified":"2022-04-18T17:04:44","modified_gmt":"2022-04-18T14:04:44","slug":"5-1-2022-ivanova","status":"publish","type":"post","link":"https:\/\/jfsi.ru\/en\/5-1-2022-ivanova\/","title":{"rendered":"TREE LITTER PRODUCTION AND DECOMPOSITION IN FOREST ECOSYSTEMS UNDER BACKGROUND CONDITIONS AND INDUSTRIAL AIR POLLUTION"},"content":{"rendered":"

\"\"<\/a><\/p>\n

Original Russian Text \u00a9 2021 E. A. Ivanova published in Forest Science Issues Vol. 4, No. 3,\u00a0\u00a0<\/span>Article 87<\/a><\/span><\/div>\n
\n

E. A. Ivanova<\/strong><\/span><\/p>\n

Institute of North Industrial Ecology Problems KSC RAS<\/em><\/span><\/p>\n

Akademgorodok st. 14a, Apatity, Murmansk region, 184209, Russia <\/em><\/span><\/p>\n

E-mail: ea.ivanova@ksc.ru<\/u><\/span><\/p>\n

Received 30 June 2021<\/span><\/p>\n

Revised\u00a004 August 2021<\/span><\/p>\n

Accepted 16 August 2021<\/span><\/p>\n

The paper provides an overview of Russian and foreign articles devoted to the study of the tree litter production and decomposition in forest ecosystems subjected to natural and anthropogenic factors. The spatial variability (below crown and between crown spaces) and the seasonal features of the tree litter production, its chemical composition, and decomposition processes are poorly studied. In addition, most of the works, both in Russia and foreign countries science, highlight the influence of natural factors on the litter production and the processes of its decomposition, while the impact of local sources of industrial air pollution is rarely considered. The study of the variability of the size, fractional and chemical composition and processes of decomposition of tree litter under conditions of industrial air pollution is important for predicting the dynamics of forest ecosystems subjected to the combined action of natural and anthropogenic factors and reducing the negative impact of production processes on forests.<\/span><\/p>\n

Keywords: <\/strong>forest ecosystems, tree litter, industrial air pollution, fractional composition, chemical composition, litter decomposition, litter production and decomposition seasonal variability, litter production and decomposition spatial variability<\/em><\/span><\/p>\n

\u00a0<\/em><\/span><\/p>\n

Tree litter in forest ecosystems acts as a link between plants of the upper tiers and the soil, as a source of soil organic matter and nutrients for biota and is one of the key components of biogeochemical cycles in forest biogeocenoses. Due to its chemical composition, tree litter participates in the formation of phytogenic zones of influence of trees, suppresses or accelerates the growth of herbaceous plants, affects microbial activity, soil composition (Aponte et al, 2013; Chavez-Vergara et al., 2014; Ufimtsev, Egorova, 2016; Kolmogorova, Ufimtsev, 2018; Pomogaibin E., Pomogaibin A., 2018), contributes to changes in the composition and abundance of soil microorganisms and invertebrates during the decomposition (Rakhleeva et al., 2011). Removal of leaf litter reduces the biological activity of the upper soil horizons, depletes the forest ecosystem of mineral nutrients, slows tree growth, and reduces soil respiration (Sayer, 2005; Xu et al., 2013; Ivanova et al., 2015), whereas addition of leaf litter reduces the temperature amplitude in the soil, increases nitrogen and aluminium availability (Loydi et al., 2014) and promotes higher methane production rates (Yavitt, Williams, 2015). The adding of litter in tropical forests increased the input of nitrogen and phosphorus into the soil (Wood et al., 2009), increased the concentration of nitrates and the stocks of inorganic nitrogen in the soil (Sayer, Tanner, 2010). The forest floor formed from undecomposed plant litter acts as a physical barrier to the emergence of shoots in species with small seeds, promotes the emergence and establishment of large-seeded species, maintains a microclimate favourable for herbivores and pathogens, acting as their habitat (Sayer, 2005; Dupuy, Chazdon, 2008).<\/span><\/p>\n

Quantitative and qualitative characteristics of tree litter are of practical interest for assessing the level of radiation pollution (Bondareva, Rubailo, 2016; Komissarov, Ogura, 2017), fire danger based on the accumulation of combustible materials (Arkhipov, 2014; Sobachkin et al., 2017), accumulation of heavy metals by tree plants in urbanized areas (Kopylova, 2012). The use of tree litter debris, mostly coniferous or foliar, as a source of cellulose (Danilova, Stepanova, 2017), sorption material (Alekseeva, Stepanova, 2015; Silaicheva, Stepanova, 2016; Shaimardanova et al., 2017; Sverguzova et al., 2017), calcium fertilizer (Petrochenko et al., 2015) is being actively investigated. In mathematical studies, data on the input and decomposition of plant litter are used to form models for estimating the participation of litter in the biological cycle, the relationship with atmospheric CO2<\/sub> and climate (Brovkin et al., 2012; Mironenko, 2017). In particular, data on the foliar litter dynamics of evergreen tropical forests in Panama, French Guiana, and Brazil were used to modify a global terrestrial ecosystem model to allow a more accurate estimate of gross primary productivity (De Weirdt et al., 2012). The elemental composition of tree litter is of interest for understanding the patterns of element cycles and soil formation (Meier et al., 2005; Wood et al., 2006; Wood et al., 2009; Vesterdal et al., 2012; Osipov, 2017).<\/span><\/p>\n

The parameters of tree litter are studied mainly in background conditions, unaffected by industrial air pollution from large industrial plants or thermal power plants. Air pollution is known to cause degradation of forest ecosystems, changes in forest stand structure: death of conifers and their replacement by small-leaved species (Chernenkova et al., 2016), reduction of species diversity and adaptability of plant communities, death of mosses and lichens (Salemaa et al., 2004; Hale, Robertson, 2016). Acid-forming substances and heavy metals \u2014 components of emissions \u2014 cause damage to assimilating organs of coniferous woody plants (Lukina, Nikonov, 1998; Yarmishko, Lyanguzova, 2013), reduced life span of fir-needles (Lamppu, Huttunen, 2003), almost no seed production of trees and shrubs (Tsvetkov V., Tsvetkov I. 2012). At the same time, a decrease in the activity of soil microorganisms and changes in the number of micromycetes and soil invertebrates is observed in forest ecosystems, resulting in slower decomposition of organic matter and increased thickness of forest floor (Nieminen et al., 1999; Zenkova, 2000; Polyanskaya et al., 2001; Nikonov et al., 2001; Fomicheva et al., 2006; Lukina et al., 2008; Vorobeichik and Pishchulin, 2009, 2016). The accumulation of Cu and Ni in forest soils near metallurgical plants leads to a deficit of basic cations (exchangeable Ca, Mg, K) in the organic layer (Derome, Lindroos, 1998). Even when the technogenic load is reduced, the death of the stand continues (Vorobeichik et al., 2014), the value of radial growth of trees in the pollution zone remains significantly lower than the control and background values (Chernenkova et al., 2012). In the vicinity of the Severonickel Combine, coniferous forests remain in a critical condition despite a reduction in emissions (Chernenkova et al., 2011; Lyanguzova et al., 2018). In this regard, the study of the processes of formation and decomposition of tree litter, as one of the key links in biogeochemical cycles, is of particular interest for understanding the dynamics of the functioning of forest ecosystems under changing man-induced loads.<\/span><\/p>\n

The aim of this paper is to review the current state of research on the formation and decomposition of tree litter in forest ecosystems.<\/span><\/p>\n

METHODOLOGICAL APPROACHES TO THE STUDY OF THE CHARACTERISTICS OF TREE LITTER AND ITS DECOMPOSITION PROCESSES<\/strong><\/span><\/p>\n

International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) has developed a detailed toolkit for participants on tree litter sampling and analysis (Ukonmaanaho et al., 2016). The translated guidelines for integrated monitoring, including the methods of the ICP Forests programme, provide recommendations for both the selection of litter and the assessment of decomposition rate (Guide\u2026, 2013). Major works analyse the methods and results of various experiments in boreal and low-disturbed forests (Berg, McClaugherty, 2008) and describe the most common and specific methods (ecological, chemical, microbiological, etc.) for studying plant litter decomposition processes comprehensively (Methods…, 2005). Study of the literature showed that field research methods vary considerably, depending on the climatic features of the area, the composition of the stand and the research objectives.<\/span><\/p>\n

A number of modern papers present already known and proven methods for the sampling of tree litter. The most commonly used litter traps are box (preferably with a mesh bottom for water drainage) and collecting funnel located 1\u20131.5 m above the ground. For sampling the material directly from the ground surface, templates of different sizes are used (Table). In addition, litter is sometimes collected from the surface and without the use of a template from survey plots (Boldeskul et al., 2015; Ufimtsev, Egorova, 2016; Kolmogorova, Ufimtsev, 2018). Preston et al. (2006) simultaneously used different designs for collecting litter: plastic containers 27.3 cm in diameter and 30 cm high with a mesh bottom and 1 m2<\/sup> square nets laid on the forest floor to capture the branches.<\/span><\/p>\n

Table. Examples of the most commonly used types of tree litter collection equipment<\/span><\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n
Design<\/span><\/td>\nSize<\/span><\/td>\nSamples<\/span><\/td>\n<\/tr>\n
Box<\/span><\/td>\n0.98 m2<\/sup><\/span><\/td>\nBazilevich et al., 1978<\/span><\/p>\n

Bryanin, Abramova, 2017<\/span><\/p>\n

Abramova et al., 2018<\/span><\/td>\n<\/tr>\n

1 m2<\/sup><\/span><\/td>\nRodin et al., 1967<\/span><\/p>\n

Ermakova, 2009<\/span><\/p>\n

Boev et al., 2018<\/span><\/td>\n<\/tr>\n

50\u00a0\u00d7\u00a050 cm<\/span><\/td>\nLikhanova, 2014<\/span><\/p>\n

Osipov, 2017<\/span><\/p>\n

Yusupov et al., 1995<\/span><\/td>\n<\/tr>\n

80\u00a0\u00d7\u00a080 cm<\/span><\/td>\nKop\u00e1\u010dek et al., 2010<\/span><\/td>\n<\/tr>\n
Funnel<\/span><\/td>\n0.2-0.5 m2<\/sup><\/span><\/td>\nUkonmaanaho et al., 2008<\/span><\/p>\n

Kouki, Hokkanen, 1992<\/span><\/p>\n

Jonczak, Parzych, 2014<\/span><\/p>\n

Berg et al., 1999<\/span><\/p>\n

Stojni\u0107 et al., 2019<\/span><\/p>\n

Ivanova, Lukina, 2017<\/span><\/td>\n<\/tr>\n

Template<\/span><\/td>\n0.031 m2<\/sup><\/span><\/td>\nReshetnikova, 2011<\/span><\/p>\n

Vedrova, Reshetnikova, 2014<\/span><\/td>\n<\/tr>\n

100\u00a0\u00d7\u00a0100\u00a0cm<\/span><\/td>\nBessonova et al., 2017<\/span><\/td>\n<\/tr>\n
0.25 m2<\/sup><\/span><\/td>\nNakazato et al., 2021<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

 <\/p>\n

The spatial variability of tree litter inflow to the soil surface is rarely considered. There are options for arranging the equipment in a non-random manner, but without specifying details (Ukonmaanaho et al., 2008); randomly (Dearden et al., 2006; Nov\u00e1k et al., 2014; Boev et al., 2018); evenly across the site (Yusupov et al., 1995; Stojni\u0107 et al, 2019); diagonally in sites (Albrektson, 1988); in a straight line 10 m apart (Michopoulos et al., 2020); in two lines (Meier et al., 2005; Ermakova, 2009); in a uniform grid on the site (Jonczak and Parzych, 2014); in different parts of the slope (Wood et al., 2006; Bessonova et al., 2017). A detailed study of the influence of stand structure is expressed in the distribution of equipment by parcel type (Lukina, Nikonov, 1996), below the crowns\/between the crowns (Ivanova, Lukina, 2017). Tsandekova O.\u00a0L. (2018), investigating the dynamics of ash accumulation in Acer negundo<\/em> litter, conducted sampling at sampling sites in different conditions of crown density, taking into account the influence zones of trees: in sparse stands and in stands with crown closure of 50\u201360%, litter was collected in the subcrown and near-front zones, and in stands with crown density of 100% \u2014 in the near-trunk and inter-crown zones. Similarly, in the study of the chemical composition of Scots pine litter, samples were taken in the under-crown, near-front (inter-crown), and outer zones on sampling sites in sparse (open stand), thin and dense forest stands (Kolmogorova and Ufimtsev, 2018).<\/span><\/p>\n

The frequency of material sampling depends largely on the climatic zone in which the study is carried out, and can be done monthly\/every 2 weeks during the warm period and once during the winter (Yusupov et al., 1995; Ukonmaanaho et al., 2008; Lenthonen et al., 2008; \u0164upek et al., 2015; Bryanin and Abramova, 2017); monthly during the growing season without sampling for the winter period (Shpakovskaya and Rozhak, 2014); every two weeks (Wood et al., 2009); only in spring and autumn (Likhanova, 2014; Nov\u00e1k et al., 2014; Ivanova and Lukina, 2017); three times a year: in spring, late summer and autumn (Kop\u00e1\u010dek et al., 2010); or once in autumn (Boldeskul et al., 2015; Boev et al., 2018). In tropical forests, sampling periods counted in days (De Weirdt et al., 2012). In large-scale studies covering sites in different climates, sampling frequencies can vary from 3 to 12 times per year depending on site location (Berg et al., 1999; Berg, Meentemeyer, 2001).<\/span><\/p>\n

In order to study the tree litter fraction composition, the plant material is sorted after sampling. Depending on the purpose of the study, only two parts could be distinguished in the litter: the fir-needles and a mixed fraction consisting of all other collected components (seeds, cones, bark etc.) (Berg et al., 1999; Berg, Meentemeyer, 2001). The litter was also divided into fractions: green needles, perennial needles and remaining fractions, while increasing the number of sampling periods (Ukonmaanaho et al., 2008). When sampling was from the ground surface, in addition to tree litter fractions (needles\/leaves, bark, twigs and cones), dwarf shrub litter, moss litter, lichens, grasses could be identified (Yusupov et al., 1995; Preston et al., 2006; Reshetnikova, 2011; Hilli, 2013; Sobachkin et al., 2017; etc.). There are also papers describing an even more thorough accounting of the tree litter fractions, distinguishing fruit, buds, seeds and ament and other fractions (Ermakova, 2009; Shpakovskaya, Rozhak, 2014; Ivanova, Lukina, 2017). In terms of the study of tree litter as the L horizon of the forest floor, it is also possible to divide the plant material into active (leaves, needles, chaff, seeds) and inactive (cones, small branches, bark) fractions (Karpachevskii et al., 1980).<\/span><\/p>\n

Studies of litter characteristics are most often devoted to a rather short observation period \u2014 up to 4-5 years, but there are also long-term studies. \u0164upek et al. (2015) used data from the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) from 1996 to 2011 and studies by the Finnish Forest Research Institute (Metla) from 1960 to 2010. Lenthonen et al. (2008) studied time series for needle litter, tree growth, microstrobila (male pollinic cone) litter and daily weather data for 43 years from 1961 to 2004. In south-eastern Finland, Scots pine needle litter had been sampled over a period of 24 years (1962\u20131986) (Kouki and Hokkanen, 1992). Long-term observations of tree litter parameters are valuable for understanding the functioning of forest ecosystems in response to climate change.<\/span><\/p>\n

 <\/p>\n

Litter decomposition<\/em><\/span><\/p>\n

The study of litter decomposition processes is mainly based on field experiments on incubating plant samples of active litter fractions (needles\/leaves) directly in stands for periods ranging from 2-3 (Rakhleeva et al., 2011; Likhanova, 2014) to 4-6 years (Moore et al., 2006; Symonds et al., 2013). There are also studies covering just one season (Abramova et al., 2018). The frequency of sampling varies depending on the objectives of the study, climatic features of the area. When the initial decomposition stages were examined in more detail, the intervals ranged from a few days to a month (De Marco et al., 2007; Wood et al., 2009; Abramova et al., 2018). For the overall assessment of litter mass loss and changes in its chemical parameters, the periods ranged from a few months (Rakhleeva et al., 2011) and half a year (Aponte et al., 2013) to a year.<\/span><\/p>\n

In the described incubation experiments litter samples were deposited for decomposition in mesh bags made of inert material: nylon (Rakhleeva et al., 2011), plastic (Wood et al, 2009), kapron (Likhanova, 2014), glass fibre (Ogden and Schmidt, 1997), polypropylene (Moore et al., 2006), terilene (polyethylene terephtalate) (Berg et al., 1993) with different hole sizes, which depended on the size of plant residues. For example, leaf litter from oak, birch, robinia, aspen and pine were placed in 1.5\u00a0\u00d7\u00a01.5\u00a0mm mesh bags, while for douglas-fir litter the bags had 1\u00a0\u00d7\u00a00.6\u00a0mm mesh size to avoid sample loss (Van Nevel et al., 2014). In studies of invertebrate participation in litter decomposition, it is possible to use a combined option where the lower part of the bag uses a mesh with smaller cells (0.5\u20131 mm) and the upper part with larger cells (0.2\u20131 cm) for biota access (Wood et al., 2009; Rakhleeva et al., 2011; Slade, Riutta, 2012). In addition to cloth bags, there are mentions of the use of 100\u00a0\u00d7\u00a0100\u00a0\u00d7\u00a05 cm containers (De Marco et al., 2007).<\/span><\/p>\n

The spatial patterns of litter decomposition and changes in its chemical composition are as little studied as its quantitative characteristics. An example of a study of tree influence zones can be found in the work of E. L. Vorobeichik and R. G. Pishchulin (2011), which studied the decomposition of pure cellulose in the near-trunk areas (at 0.2\u20130.4\u00a0m from the trunk), in the middle of crown projection (1.2\u20131.8\u00a0m), in the canopy gaps (3.8\u20135.3\u00a0m) and on the opposite side from the gap under a closed forest canopy (2\u20133\u00a0m from the trunk). The influence of the stand structure was also assessed when the samples were located below the crowns\/between the crowns of spruce and pine forests (Lukina et al., 2017, Ivanova et al., 2019).<\/span><\/p>\n

AMOUNT AND FRACTIONAL COMPOSITION OF TREE LITTER:<\/strong><\/span>
\nNATURAL FACTORS AND INDUSTRIAL AIR POLLUTION<\/strong><\/span><\/p>\n

The quantity and quality of tree litter regulates carbon accumulation, element cycles in forests. Within the framework of the International Biological Program, work has been carried out to assess the weight and fractional composition of litter in taiga forests of European Russia (Kazimirov & Morozova 1973; Zaboeva 1975; Manakov & Nikonov 1981). Numerous long-term observations of plant litter volumes in the same years were carried out abroad (Bray and Gorham, 1964; Flower-Ellis, 1985; Kouki and Hokkanen, 1992).<\/span><\/p>\n

 <\/p>\n

Influence of natural factors on the formation of tree litter<\/em><\/span><\/p>\n

Among the natural factors affecting tree litter formation, there is a dependence of coniferous litter mass on geographic latitude: among sites of similar fertility, the amount of coniferous litter is lower for sites located in the north (Albrektson, 1988; Berg et al., 1999). The size and composition of the litter depends on the composition of the forest stand (Shpakovskaya and Rozhak, 2014), the annual growth of trees, and their age (Pedersen and Bille-Hansen, 1999). In particular, litter mass (needles, cones and bark plus dead grass) in a mature pine forest exceeded its for a middle-aged plantation (Sobachkin et al., 2017). In recent decades, relationships between above-ground tree biomass and litter have been assessed based on long-term monitoring data (Lenthonen et al., 2008; Ukonmaanaho et al., 2008; Ilvesniemi et al., 2009; Nov\u00e1k et al., 2014). Thus, in the pine forests of northern Finland, the Scots pine needles litter depends on the production and mass development of needles, which occurs 4-6 years earlier (Lenthonen et al., 2008). The amount of litter may depend on weather conditions: unfavorable climatic factors, cooling, and lack of precipitation inhibit the development of plant leaf apparatus (Likhanova, 2014). A long-term study in south-eastern Finland showed a positive association of Scots pine needle litter with mean July temperature and high temperatures between March and April: the high temperature in July coincided with an increase in litter amount in the same year and the following year (Kouki and Hokkanen, 1992). In young oak stands, a positive relationship was found between annual litter and precipitation and a negative relationship with summer temperature (Nov\u00e1k et al., 2014). A high yield of pine seeds and cones is associated with the warm weather of previous years (Nekrasova, 1957).<\/span><\/p>\n

Litter size exhibits species specificity, and an increase in species diversity leads to an increase in litter production (Scherer-Lorenzen et al., 2007). The average annual litter in the spruce forests of Finland was higher than that of pine forests (Ukonmaanaho et al., 2008); in the area with Siberian stone pine cultivation, there was almost three times more litter than in the spruce forest (Reshetnikova, 2011). Differences in the amount of litter fall of Hudson Bay pine (Pinus banksiana<\/em>) and black spruce (Picea mariana<\/em>) growing along the Boreal forest transect in northern Canada have been attributed to site conditions (soil structure and drainage) and forest floor thickness (Preston et al., 2006).<\/span><\/p>\n

The activity of insect pests leads to changes in the litter production: in mature spruce stands in the Lake Ple\u0161n\u00e9 catchment (Czech Republic), the amount of litter increased after bark beetle infestation (Kop\u00e1\u010dek et al., 2015).<\/span><\/p>\n

The fractional composition of tree litter, as well as its total mass, may depend on the age or species composition of the stand. In forb-green-moss pine forest of various ages in the forest-steppe zone cones and needles predominated in the fractional composition of litter. In the middle-aged stand, the needles accounted for most of the litter (52.2%), while in the mature stand the share of needles decreased to 36.7%. The participation of cones in litter is also explained by age differences in stands: in the litter of a mature stand, it is higher than in a mid-age stand (Sobachkin et al., 2017). In 40-year-old stands of the main forest-forming species of Siberia under cedar about 90% of the litter mass is needles, under pine, larch and spruce 40\u201350% are needles and 20\u201345% are branches (d \u2264 10 mm). In birch and aspen forests 70\u201374% of the litter mass is represented by leaves and 21\u201329% \u2014 by branches (Reshetnikova, 2011). High values of the mass of needle, bark, and branch litter can also be caused by the action of dangerous weather phenomena \u2014 strong winds and snowstorms (Report…, 2015).<\/span><\/p>\n

 <\/p>\n

Seasonal and spatial variability of tree litter formation<\/em><\/span><\/p>\n

Tree litter formation processes (its mass and fractional composition) in seasonal dynamics and depending on forest canopy pattern structure are poorly studied. It is known that in spruce-beech and fir-spruce-beech forests of the Ukrainian Carpathians, most of the annual amount of litter occurs in October and November due to an increase in needles and leaves part in its composition. At the same time, the dynamics of needle supply has the form of a curve with two peaks at the beginning and at the end of the growing season and with a minimum at the beginning of autumn (Shpakovskaya and Rozhak, 2014). In a burnt forest and in control forest, the maximum inflow of litter occurs in October and the minimum \u2014 in July (Bryanin, Abramova, 2017). The bulk of the leaves of the flat-leaved birch in the forest stands of the Khamar-Daban ridge (Southern Baikal region) begins to fall at the end of the second decade of September, with a maximum rate during the third decade of September \u2014 the first pentad of October, and the bulk of the leaves of the Siberian mountain ash fall within 3\u20134 weeks \u2014 from the beginning of the second decade of September until the end of the first decade of October (Ermakova, 2009). In medium taiga spruce forests, the winter-spring period accounts for 52\u201358%, the summer period for 20\u201323%, and the autumn period for 22\u201325% of the total mass of litter (Likhanova, 2014). In 40-year-old coniferous stands of Siberia, the mass of litter in the summer-autumn period is higher than in winter (Reshetnikova, 2011). As part of a study of the role of litter in the formation of phytogenic tree fields in coal mine dumps, differences in the fractional composition of the litter horizon L were found in different zones: needles and cones dominated under the crowns, while in the outer zone the litter consisted almost entirely of meadow vegetation litter (Ufimtsev, Egorova, 2016).<\/span><\/p>\n

 <\/p>\n

Anthropogenic factors affecting the formation of litter<\/em><\/span><\/p>\n

Fires as an anthropogenic factor lead to significant changes in the functioning of forest ecosystems. In the post-fire larch forest in the foothills of the Tukuringa Ridge (Upper Amur Region), the input of litter from the aboveground part of the vegetation was reduced by 2.8 times compared with the control forest. In addition, the fractional composition was also characterized by differences: in the control forest, there was a gradual decrease in the fractional composition of the total amount of litter in the series leaves \u2014 fir \u2014 needles \u2014 branches \u2014 grass \u2014 other fractions (33%, 26%, 21%, 11%, 9% respectively), whereas in the post-fire stand, grass litter was dominating and the fractional decrease occurred in reverse order: grass \u2014 other fractions \u2014 fir \u2014 needles \u2014 leaves \u2014 branches (28%, 23%, 22%, 20%, 7%, respectively) (Bryanin, Abramova, 2017). With a prolonged non-fire period, the branch\/tree ratio in the litter increases due to reduced needle litter, resulting in a reduced decomposition rate (Dearden et al., 2006).<\/span><\/p>\n

Air pollution with heavy metals and acid-forming substances leads to damage to the assimilating organs of coniferous woody plants and a decrease in the life span of needles \u2014 defoliation of trees is not only in phenological terms, contributing to an increase in the amount of litter (Nieminen, Helmisaari, 1996; Rautio et al., 1998; Lukina, Nikonov, 1998; Lamppu and Huttunen, 2004; Nikonov et al., 2004; Yarmishko and Lyanguzova, 2013). As pollution levels increase, the number of female cones per tree decreases (Stavrova, 1990), the proportion of large cones decreases, the number of damaged and diseased cones increases, cone diameter and average raw weight decrease (Tsvetkov V., Tsvetkov I., 2003). The proportion of epiphytic lichens in litter as an element of biogeocenosis sensitive to air pollution decreases in the area affected by Severonickel Combine emissions. At the same time, there are clear trends towards an increase in the total mass of litter due to pine needles and bark, despite a decrease in emissions over 20 years, which may be due to weakening of trees and premature die-off of individual organs (Ivanova, Lukina, 2017).<\/span><\/p>\n

FEATURES OF THE CHEMICAL COMPOSITION OF TREE LITTER<\/strong><\/span><\/p>\n

The chemical composition of fresh tree litter determines its quality for the decomposing organisms and consequently influences the rate of decomposition and the change in the chemical composition of the plant residues during the mineralisation process. Thus, the work of N.\u00a0V.\u00a0Likhanova (2014) showed that birch leaves litter decomposition was the most intensive, where the \u0421 : N ratio was 35\u201338, while this ratio varied from 38 to 43 for spruce and pine needles, from 43 to 60 for tree branches, and from 105 to 142 for bark. The low content of nitrogen and phosphorus in the needles leads to an increase in the \u0421 :\u00a0N ratio, which increases the chance of nitrogen immobilization during the early stages of decomposition (Symonds et al., 2013).<\/span><\/p>\n

Natural factors determining the chemical composition of tree litter<\/em><\/span><\/p>\n

Both the quantitative characteristics and the chemical composition of plant residues depend on various factors. Concentrations of Mg, N and K were found to decrease with increasing age of beech stands (Trap et al., 2013). In the artificial plantation of black locust, the N, K, Mg, P input with litter was higher in the lower third of the studied slope of Voyskovoye gully (Bessonova et al., 2017). Ca concentration in needle and leaf litter was negatively associated with annual precipitation, probably due to washout by rain and melting snow (Berg et al., 2017).<\/span><\/p>\n

Numerous works have shown that the content of elements in the litter depends on the tree species (Preston et al., 2006; Ukonmaanaho et al., 2008; Aponte et al., 2013; Jonczak and Parzych, 2014; Boev et al., 2018; Neumann et al., 2018; Becker et al., 2018). Norway spruce (Picea abies<\/em>) and lodgepole pine (Pinus contorta<\/em>) needles litter contain more calcium than Scots pine needles litter (Pinus sylvestris<\/em>). In addition, Ca concentrations in fresh litter are positively related to P, K, and Mg concentrations: for pine species (Pinus contorta<\/em> and Pinus sylvestris<\/em>) Ca content was positively related to Mg and Mn concentrations, for Scots pine (Pinus sylvestris<\/em>) \u2014 with Mg content (Berg et al., 2017). In undisturbed 40-year-old Siberian stands, the carbon to nitrogen ratio in cedar litter was 101, in pine was 98, in larch and spruce \u2014 87, in birch \u2014 76 and in aspen \u2014 118 (Reshetnikova, 2011).<\/span><\/p>\n

The fauna also introduces changes in the chemical composition of plant residues. In the needles falling off after the forest desiccation due to infection of the forest with bark beetles, the concentration of N increased for 1\u20133 years, and the C :\u00a0N and C :\u00a0P ration decreased, indicating decomposition by endophytes already on the trees. At the same time, the concentrations of Mg, K, and P increased in the total litter due to an increase in the proportion of rowan litter (Kop\u00e1\u010dek et al., 2015).<\/span><\/p>\n

 <\/p>\n

Seasonal and spatial variability of the chemical composition of tree litter<\/em><\/span><\/p>\n

Seasonal and spatial features of the chemical composition of the litter, both in Russia and abroad, have been studied rather poorly. The larch litter taken in spring was 10% enriched in N and 40% depleted in Ca compared to the litter taken in autumn. Changes in lignin\u00a0:\u00a0N, C\u00a0:\u00a0N and C\u00a0:\u00a0P ratios after the winter season indicated the beginning of litter decomposition (Chuldiene, 2017). According to other data, the nitrogen content in the total pine litter in the conditions of rockfall increased uniformly during the growing season (Kolmogorova, Ufimtsev, 2018). In Finnish forests, there were two main periods when C and N were deposited in the ground: May\u2013October and November\u2013April, with higher depositions in the first period, peaking in September (Portillo-Estrada et al., 2013). In pine forests in Poland, the Mn, Zn and Ni content in pine needles in 2007 was shown to be higher in autumn, whereas in 2009 it was higher in spring (Jonczak and Parzych, 2014). Under the conditions of the rock dump (in the reclaimed areas of opencast coal mine overburden), the content of total phosphorus in the Scots pine litter reached a maximum in the sub-crown and near-front zones of the dense stands (Kolmogorova, Ufimtsev, 2018). In the Acer negundo<\/em> litter, greatest accumulation of the ash component occurs in the under-crown and near-trunk zones of single trees in sparse stands compared to other groups of trees and with control forest (Tsandekova, 2018).<\/span><\/p>\n

 <\/p>\n

Changes in the chemical composition of tree litter caused by anthropogenic factors<\/em><\/span><\/p>\n

Sharp changes in the functioning of forest ecosystems caused by anthropogenic factors significantly affect the chemical composition of tree litter. In the post-pyrogenic larch forest in the foothills of the Tukuringa Range, the litter is dominated by organic remains enriched in nitrogen but poor in carbon. In larch needles on the control sample plot, the C :\u00a0N ration approaches 170; in a stand damaged by fire, its does not exceed 110 (Bryanin, Abramova, 2017).<\/span><\/p>\n

Atmospheric pollution leads to disruption of the processes of retranslocation of elements within trees (Lukina and Nikonov 1996, 1998; Nieminen and Helmisaari, 1996; Rautio et al, 1998; Steinnes et al, 2000; Kiikkil\u00e4, 2003; Tarkhanov, 2009; Yarmishko and Lyanguzova, 2013; Sukhareva and Lukina, 2014; Vacek et al., 2016). In the impact zone of the Middle Ural copper smelter compared to the control zone, more Ca was supplied with pine needle litter (Yusupov et al., 1995). The long-term effect of acid precipitation and nitrogen saturation in Czech spruce forests has caused a decrease in Ca, Mg, and Mn concentrations and Ca :\u00a0Al and Mg :\u00a0Al ratios, increase in N content and N :\u00a0Mg ratio in the litter (Kop\u00e1\u010dek et al., 2010). In defoliating forests and pollution-induced sparse forests in the area of the Severonickel Combine, a deterioration in the quality of plant material was recorded: an increase in heavy metals Ni and Cu and a decrease in Ca, Mn, K, Mg (Lukina et al., 2017; Ivanova et al., 2019), and lignin content increased in the birch leaf litter when approaching the combine (Artemkina, 2018).<\/span><\/p>\n

DECOMPOSITION OF TREE LITTER IN FOREST ECOSYSTEMS<\/strong><\/span><\/p>\n

The evaluation of litter decomposition processes is reflected in numerous works from all over the world. The rate of plant residue mass loss and changes in chemical composition are influenced by various environmental factors: stand composition, soil conditions, weather, microbial activity, etc. (Fig. 1). The current concept is that litter quality is the dominant factor at large spatial scales, and the activity of the decomposing organisms is regulated by climate and litter quality (Bradford et al., 2016).<\/span><\/p>\n

\"\"

Figure 1.<\/strong> Factors influencing the litter decomposition processes<\/span>
(acc. to Krishna, Mohan, 2017)<\/span><\/p><\/div>\n

\u00a0<\/em><\/span><\/p>\n

Influence of natural factors on tree litter decomposition processes<\/em><\/span><\/p>\n

One of the main factors affecting the rate of decomposition is the activity of soil biota: invertebrates, microorganisms, and fungi (Vorob\u2019eva, Naumova, 2009). Litter decomposition in the most surface soil horizon is attributed to the predominance of saprotrophic fungi and the absence of mycorrhizal fungi (H\u00f6gberg et al., 2017). However, the larger soil fauna is also influential. Slade, Riutta (2012) showed that macrofauna accounted for 22\u201341% of the total mass loss of leaf litter. Earthworms increased mass loss of litter with lower C\u00a0:\u00a0N (Belote and Jones, 2009). In a laboratory experiment, high concentrations of Cd, affecting earthworm activity, inhibit leaf litter decomposition and lead to a decrease in soil fertility (Liu et al., 2020).<\/span><\/p>\n

The mineralisation of tree litter depends on the hydrothermal conditions of soils (Kuznetsov, 2010; Kuznetsov, Osipov, 2011) and is positively related to mean annual temperature and annual precipitation (Albrektson, 1988; Pausas, 1997; Portillo-Estrada et al., 2016). In Mediterranean sites, the decomposition of senescent pine needles was faster than in continental forests of the Pyrenees, and a sharper reduction in decomposition rates was observed there when stands were thinned (Blanco et al., 2011). A study on the effect of altitude on the decomposition of plant residues revealed that decomposition processes are mainly influenced by the quality of the litter. These processes do not depend so much on altitude but rather on a combination of specific conditions such as temperature, precipitation, different types of forest floor and different trophic interactions between the plants and the microbial community (Marian et al., 2017). The decomposition rate of thin woody residues (branches of different diameters) increased from north to south in a large-scale study with plots along a climatic gradient from Northern Finland to Central Estonia (Vavrova et al., 2009).<\/span><\/p>\n

Since the fractional and chemical composition of the litter depends on the species composition of the forest stand, the process of its decomposition has corresponding features. It has been demonstrated that the dynamics of the content of elements during the decomposition of litter on Mount Vesuvius in four different pine species (Pinus pinea, P. laricio, P. sylvestris<\/em> and P. nigra<\/em>) is mainly governed by their original content. For example, P. nigra <\/em>litter, the richest in nitrogen, released N during decomposition. Potassium was accumulating in P. sylvestris<\/em> litter, while Mn was accumulating in P.\u00a0nigra<\/em> and P.\u00a0pinea<\/em> litter, which had the lowest initial concentrations of K and Mn, respectively (De Marco et al., 2007). Spruce needle litter, characterized by a higher content of nutrients and narrower C\u00a0:\u00a0N and lignin\u00a0:\u00a0N ratios, within two years was decomposing noticeably faster than pine needle litter. Wherein the litter of birch leaf (Betula pendula<\/em>), growing in pine forests and characterized by a lower N\u00a0:\u00a0P ratio, decomposes faster than downy birch litter (B. pubescens<\/em>) in spruce forests (Ivanova et al., 2019). In coastal forests of British Columbia, grape maple litter with higher concentrations of N, P, Ca, Mg, K, Fe and Zn was decomposing significantly faster than conifer litter (Ogden and Schmidt, 1997). However, the rate of degradation of pure cellulose is higher in spruce-fir forests than in birch forests (Vorobeichik and Pishchulin, 2011). Subordinate foliage plants with sharply contrasting feeding and water yield characteristics compared to the dominant evergreen plants significantly influenced litter decomposition at the community level, despite their low abundance (Guo et al., 2020).<\/span><\/p>\n

A number of experiments in different types of terrestrial ecosystems have shown: the decomposition process depends on the fractional composition of the incoming litter (Bobkova, 2000; Fang et al., 2015). In undisturbed of 40-year stands in Siberia, woody species that annually shed their leaves (needles): larch, aspen and birch (Reshetnikova, 2011; Vedrova, Reshetnikova, 2014) are characterized by the maximum mass loss in the annual cycle of decomposition.<\/span><\/p>\n

Many studies have shown the influence of the initial quality of the litter, determined by concentrations of nutrient, heavy metals, element ratios, on the decomposition rate (Berg, 2000; Wardle et al., 2003; De Marco et al., 2007; Zhang et al.,2008; Berg, McClaugherty, 2008; Rahman et al., 2013; Tu et al., 2014; Lukina et al., 2017; Ivanova et al., 2019). Litter with a higher nitrogen content decomposes faster than those with low nitrogen and high lignin concentrations (Wardle et al., 2003). Accordingly, the stoichiometric C\u00a0:\u00a0N and lignin\u00a0:\u00a0N ratios in plant residues have a significant effect on decomposition: the narrower these ratios, the higher the rate of decomposition (Berg and McClaugherty, 2008; Lukina et al., 2017; Ivanova et al., 2019). At the early stages of decomposition, nitrogen has a stimulating effect, while at later stages, on the contrary, it inhibits the decomposition rate, while Ca and Mn have a significant positive effect (Berg, 2000; Berg and Meentemeyer, 2001; Davey et al., 2007; Berg, 2014 ). Some authors have studied an excessive intake of one element, most commonly nitrogen. Tu et al. (2014) found that high nitrogen input reduced the rate of decomposition in forests, and the mass of undecomposed litter was closely related to residual lignin during the decomposition process. During the early stages of decomposition, nutrients such as nitrogen and phosphorus as well as water-soluble organic compounds have the greatest effects, whereas in the later stages lignin is the main determinant of decomposition dynamics (Rahman et al., 2013). Mineral N application or mixing of litter of different quality, expressed in C : N ratio and N content, increased the intensity of mineralization of N-poor litter fractions and inhibited the release of CO2<\/sub> during the decomposition of N-rich litter (Bonanomi et al., 2014; Larionova et al., 2017). Under the conditions of the incubation experiment, sodium chloride and sodium sulphate exhibited an inhibitory effect on the biota involved in the decomposition of birch litter, while, in contrast, when the litter was treated with solutions of iron salts, an increase in the mineralising activity of the biota was observed (Smirnova et al., 2017).<\/span><\/p>\n

 <\/p>\n

Changes in the chemical composition of plant residues during decomposition<\/em><\/span><\/p>\n

In the process of mineralization of plant material, changes in the chemical composition are observed. Pine and spruce needle litter at the initial stages of decomposition (up to 165 days) releases monoterpene hydrocarbons in the gas phase at a rate comparable to emissions from living needles of these trees (Isidorov et al., 2010). In undisturbed 40-year-old Siberian stands, as plant residues decompose, their carbon, P and K contents decrease and Mg concentration increases (Reshetnikova, 2011). Changes in the content of elements can be interrelated. In the subarctic to cool-temperate highlands of Canada, the decomposition of assimilating tree organs litter usually retained N in the decomposing litter until about 50% of the initial C remained. Peak N content in litter was observed to be between 72% and 99% of the original remaining C with C : N ratios ranging from 37 to 71. The rate of phosphorus loss inversely correlated with the initial concentration of phosphorus in the litter, which varied from 0.02% to 0.13%. There was a trend toward higher nitrogen and phosphorus retention during litter decomposition at sites with lower C\u00a0:\u00a0N and N\u00a0:\u00a0P ratios, respectively (Moore et al., 2006). As the leaf\/coniferous litter decomposes, an increase in Ca concentration is shown, often followed by a decrease. The maximum calcium concentrations are positively related to manganese and negatively related to nitrogen, which can have a direct influence on the decomposition rate (Berg et al., 2017).<\/span><\/p>\n

 <\/p>\n

Seasonal and spatial variability of tree litter decomposition<\/em><\/span><\/p>\n

Seasonal and spatial patterns of decomposition, in turn, depend largely on the activity of soil destructors and the influence of trees: in winter the process slows down considerably (Vorob\u2019eva, Naumova, 2009). Litter mass losses in spruce and pine forests were higher between tree crowns compared to undercrown spaces (Lukina et al., 2017; Ivanova et al., 2019), but net cellulose degradation rates were higher in spruce-fir and birch forests under tree crowns compared to canopy gaps (Vorobeichik and Pishchulin, 2011).<\/span><\/p>\n

 <\/p>\n

Anthropogenic factors influencing the processes of decomposition of tree litter<\/em><\/span><\/p>\n

Forest management can change the rate of decomposition and cycling of elements. In beech and spruce forests with high intensity forest management, higher rates of litter decomposition and release of most nutrients were observed than in unmanaged deciduous forests (Purahong et al., 2014). In a plantation of Chinese pine (Pinus tabulaeformis <\/em>Carriere), N during litter decomposition was accumulating until the ratio of acid-non-hydrolysable residues to nitrogen was reached 57\u201369. At the same time, thinning accelerated the decomposition of nitrogen-poor litter and also increased nitrogen accumulation (Chen et al., 2014). In 4\u20136-year old cutover patches after clear-cutting in medium taiga spruce forests, the highest decomposition rate was observed for birch leaves in the first year, while for spruce and pine needles an increase in decomposition rate was observed in the second year of the experiment. The tree litter components belonging to the inactive fraction (branches, bark, cones) were decomposing very slowly (Likhanova, 2014). In the post-fire larch forest (12 years after the fire), in the initial stages of decomposition, as well as in the control larch forest, the maximum losses were observed in the first 75 days of the experiment, and the decomposition rate in the studied forest ecosystems decreased in the series: grass\u2013leaves\u2013needle\u2013branches (Abramova et al., 2018).<\/span><\/p>\n

The extremely change in the litter decomposition processes is brought about by airborne industrial pollution. In the area affected by airborne emissions from the smelter, the proportion of poorly decomposed dead wood was higher than in the background area in the southern taiga, indicating a strong inhibition of tree residues degradation (Bergman, Vorobeichik, 2017). Soil contamination with heavy metals (Cu, Pb, Cd, Zn) reduced the rate of cellulose degradation in spruce-fir forests and birch forests by 2.7\u20135.4 times (Vorobeichik, Pishchulin, 2011). The use of tree-ring dating and an exponential decomposition model made it possible to determine that pollution had led to a decrease in the rate constant of wood decomposition by 16\u201360% (Dulya et al., 2019). In the Sudbury (Ontario) copper-nickel smelter impact area, a decrease in the rate of litter decomposition was observed (Freedman, Hutchinson, 1980). There, during the period of significant emission reductions, a decrease in the decomposition rate of white birch (Betula papyrifera <\/em>Marshall) leaf litter was still observed and an increase in Cu and Ni in the litter was recorded, indicating that atmospheric inputs of Cu and Ni from Sudbury smelters remained high enough at the time of the 1999\u20132001 experiment to have a negative impact on degradation processes (Johnson, Hale, 2004). Scots pine needle litter 0.5 km from the Outukumpu copper smelter in the Harjavalta region in southwestern Finland had the lowest mass loss rate \u2014 28.1%, while in the background it was 37.9% for the entire time. In addition, copper and nickel accumulation and a decrease in the carbon\/nitrogen ratio have been observed in the impact zone over time (McEnroe and Helmisaari, 2001). In Belgium, in sandy soils contaminated with metals, a change in chemical composition during decomposition was observed: samples with initially low metal content were enriched in Cd and Zn, while metal losses were observed for samples with high content (Van Nevel et al., 2014).<\/span><\/p>\n

In the vicinity of the Severonickel Combine near Monchegorsk, a decrease in the rate of decomposition of birch leaves was observed (Kozlov, Zvereva, 2015); in spruce and pine forests, a decrease in the rate of litter decomposition was noted, associated with a decrease in litter quality: increased initial content of heavy metals Ni and Cu, low content of nutrients and an increase in the lignin\u00a0:\u00a0N, C\u00a0:\u00a0N ration. In addition, during decomposition, plant residues in spruce and pine forests lost Ca, Mn, K, and Mg more intensively compared to the background and accumulated lignin, Al, Fe, Ni, and Cu (Lukina et al., 2017; Ivanova et al., 2019).<\/span><\/p>\n

 <\/p>\n

CONCLUSION<\/strong><\/span><\/p>\n

Tree litter acts as a link between tree vegetation and soil. Data on the content of elements in the litter allows us to estimate the amount of elements entering the soil and predict the rate of decomposition, during which the elements are released and re-engaged in biogeochemical cycles. In recent decades, factors affecting the litter formation and decomposition, taking into account the producing species, have been extensively investigated. Although the quantitative and qualitative characteristics of tree litter and its decomposition and mineralisation processes have been studied, the spatial and seasonal variability of these parameters and processes have been studied insufficiently. There are not enough studies devoted to the influence of local sources of air pollution \u2014 metallurgical complex enterprises, thermal power plants, nuclear power plants and others \u2014 on the tree litter. Understanding the processes of adaptation of forest ecosystems to climate change, the variability of ecosystem functions of forests requires research into the variability of size, fractional composition, chemical composition and decomposition processes of tree litter, taking into account seasonal and spatial variability (forest canopy pattern structure) under conditions of combined natural and anthropogenic factors, including atmospheric pollution. This will improve forecasts of further changes in forest ecosystems and develop recommendations for optimizing production processes to reduce the impact on forest ecosystems.<\/span><\/p>\n

 <\/p>\n

FINANCING<\/strong><\/span><\/p>\n

The research was carried out under the State Assignment of the Institute of North Industrial Ecology Problems FRC KSC RAS No.\u00a00226-2018-0111 (AAA-A18-118021490070-5) and partially under the Contract No\u00a0D-1087.2021 \u201cIntegrated research of Russian Arctic forests to improve their productivity and preserve ecosystem functions\u201d.<\/span><\/p>\n

 <\/p>\n

REFERENCES<\/strong><\/span><\/p>\n

Abramova E. R., Bryanin S. V., Kondratova A. V., Razlozhenie opada v postpirogennykh listvennichnikakh khrebta Tukuringra (Verkhnee Priamur\u2019e) (Litter decomposition in the post-fire larch forests of the Tukuringra Range (Upper Priamurie)), Sibirskii lesnoi zhurnal<\/em>, 2018, No 2, pp. 71\u201377.<\/span><\/p>\n

Albrektson A., Needle litterfall in stands of Pinus sylvestris<\/em> L. in Sweden, in relation to site quality, stand age, and latitude, Scandinavian Journal of Forest Research<\/em>, 1988, No 3, pp. 333-342.<\/span><\/p>\n

Alekseeva A. A., Stepanova S. V., Primenenie listovogo opada v kachestve sorbtsionnogo materiala dlya likvidatsii avariinykh neftyanykh razlivov (Use of leaf litter as sorption material for elimination of accidental oil spills), Zashchita okruzhayushchei sredy v neftegazovom komplekse. Sorbtsionnaya ochistka ot vrednykh primesei<\/em>, 2015, No 7, pp. 9\u201313.<\/span><\/p>\n

Aponte C., Garc\u00eda L. V., Mara\u00f1\u00f3n T., Tree species effects on nutrient cycling and soil biota: A feedback mechanism favouring species coexistence, Forest Ecology and Management<\/em>, 2013, Vol. 309, \u0440\u0440. 36\u201346.<\/span><\/p>\n

Arkhipov E. V., Dinamika nakopleniya lesnykh goryuchikh materialov v sosnovykh lesakh Kazakhskogo melkosopochnika (The dynamics of forest fuel material accumulation in the pine forests of the Kazakh Hummocks), Vestnik Altaiskogo gosudarstvennogo agrarnogo universiteta<\/em>, 2014, No 9 (119), pp. 64\u201368.<\/span><\/p>\n

Artemkina N. A., Soderzhanie lignina i tsellyulozy v opade i podstilke nenarushennykh i podverzhennykh tekhnogennomu zagryazneniyu severotaezhnykh sosnovykh lesov (The content of lignin and cellulose in the litter of undisturbed and technogenic polluted northern taiga forests), Trudy Fersmanovskoi nauchnoi sessii GI KNTs RAN. <\/em>Apatity: Izd-vo Geologicheskogo instituta FITs KNTs RAN, 2018, No 15, pp. 418\u2012421.<\/span><\/p>\n

Bazilevich N. I., Titlyanova A. A., Smirnov V. V., Rodin L. E., Nechaeva N. T., Levin F.\u00a0I., Metody izucheniya biologicheskogo krugovorota v razlichnykh prirodnykh zonakh<\/em> (Methods for studying the biological cycle in various natural zones), Moscow: Mysl\u2019, 1978, 185 p.<\/span><\/p>\n

Becker H., Aosaar J., Varik M., Morozov G., Aun K., Mander \u00dc., Soosaar K., Uri V., Annual net nitrogen mineralization and litter flux in well-drained downy birch, Norway spruce and Scots pine forest ecosystems, Silva Fennica<\/em>, 2018, Vol. 52, No 4, Article 10013.<\/span><\/p>\n

Belote R. T., Jones R. H., Tree leaf litter composition and nonnative earthworms influence plant invasion in experimental forest floor mesocosms, Biological Invasions<\/em>, 2009, Vol. 11, Iss. 4, pp. 1045\u20131052.<\/span><\/p>\n

Berg B., Albrektson A., Berg M. P., Cortina J., Johansson M.-B., Gallardo A., Mgadeira M., Pausas J., Kiratz W., Vallejo R., McClaugherty C., Amounts of litter fall in some pine forests in European transect, in particular Scots pine, Annals of Forest Science<\/em>, 1999, Vol. 56, pp. 625-639.<\/span><\/p>\n

Berg B., Berg M. P., Bottner P., Box E., Breymeyer A., Ca de Anta R., Couteaux M., Escudero A., Gallardo A., Kratz W., Madeira M., M\u00e4lk\u00f6nen E., McClaugherty C., Meentemeyer V., Mu\u00f1oz F., Piussi P., Remacle J., Vi de Santo A., Litter mass loss rates in pine forests of Europe and Eastern United States: some relationships with climate and litter quality, Biogeochemistry<\/em>, 1993, Vol. 20, Iss. 3, pp. 127\u2013159.<\/span><\/p>\n

Berg B. Litter decomposition and organic matter turnover in northern forest soils, Forest Ecology and Management<\/em>, 2000, Vol. 133, \u0440\u0440. 13\u201322.<\/span><\/p>\n

Berg B., McClaugherty C., Plant litter \u2014 decomposition, humus formation, carbon sequestration<\/em>, 2nd<\/sup> Edn. Edited by: B. Berg, C. McClaugherty, Germany: Springer-Verlag Berlin Heidelberg, 2008, 340 p.<\/span><\/p>\n

Berg B. Decomposition patterns for foliar litter \u2014 A theory for influencing factors, Soil Biology and Biochemistry<\/em>, 2014, Vol. 78, \u0440\u0440. 222\u2013232.<\/span><\/p>\n

Berg B., Johansson M.-B., Liu C., Faituri M., Sanborn P., Vesterdal L., Ni X., Hansen K., Ukonmaanaho L., Calcium in decomposing foliar litter \u2014 A synthesis for boreal and temperate coniferous forests, Forest Ecology and Management<\/em>, 2017, Vol. 403, \u0440\u0440. 137\u2013144.<\/span><\/p>\n

Berg B., Meentemeyer V., Litter fall in some European coniferous forests as dependent on climate: a synthesis, Canadian Journal of Forest Research<\/em>, 2001, Vol. 31, pp. 292\u2013301.<\/span><\/p>\n

Bergman I. E., Vorobeichik E. L., Vliyanie vybrosov medeplavil\u2019nogo zavoda na formirovanie zapasa i razlozhenie krupnykh drevesnykh ostatkov v elovo-pikhtovykh lesakh (The effect of the cooper plant on the growing stock and decomposition of coarse woody debris in the spruce and fir woodland), Lesovedenie<\/em>, 2017, No 1. pp. 24\u201338.<\/span><\/p>\n

Bessonova V. P., Nemchenko M. V., Tkach V. V., Zapas makroelementov (P, K, Ca, Mg) i azota v opade i podstilke v protivoerozionnom nasazhdenii Robinia pseudoacacia L.<\/em> (Stock of macroelements (P, K, Ca, Mg) and of nitrogen in litter fall and bedding in the antierosion stands Robinia pseudoacacia L.<\/em>), Vestnik Donskogo gosudarstvennogo agrarnogo universiteta<\/em>, 2017, Iss. 1 (23.1), Part. 1, Sel\u2019skokhozyaistvennye nauki, pp. 42\u201350.<\/span><\/p>\n

Blanco J. A., Bosco Imbert J., Castillo F. J., Thinning affects Pinus sylvestris<\/em> needle decomposition rates and chemistry differently depending on site conditions, Biogeochemistry<\/em>, 2011. Vol. 106. Iss. 3. pp. 397\u2013414.<\/span><\/p>\n

Bobkova K. S., Rol\u2019 lesnoj podstilki v funkcionirovanii hvojnyh ekosistem Evropejskogo Severa (The role of forest litter in the functioning of coniferous ecosystems in the European North), Vestnik Instituta biologii Komi NC UrO RAN<\/em>, 2000, No 9 (35), available at: https:\/\/ib.komisc.ru\/add\/old\/t\/ru\/ir\/vt\/00-35\/05.html (June 21, 2021)<\/span><\/p>\n

Boev V. A., Baranovskaya N. V., Boev V. V., Rtut\u2019 v listovom opade podtaezhnykh lesov na fonovoi territorii (Mercury in leaf litter of subtaiga forests on the natural territory), Izvestiya Tomskogo politekhnicheskogo universiteta. Inzhiniring georesursov<\/em>, 2018, Vol. 329, No 8, pp. 124\u2013131.<\/span><\/p>\n

Boldeskul A. G., Kudryavtseva E. P., Arzhanova V. S., Rol’ drevesnykh vidov v protsessakh funktsionirovaniya landshaftov chernopikhtovo-shirokolistvennykh lesov Yuzhnogo Primor\u2019ya (Role of arboreous species in the functioning of landscapes of fir-broadleaved forests in the southern part of Primorskii Krai), Sibirskii ekologicheskii zhurnal<\/em>, 2015, No 3. pp. 355\u2013362.<\/span><\/p>\n

Bonanomi G., Capodilupo M., Incerti G., Mazzoleni S., Nitrogen transfer in litter mixture enhances decomposition rate, temperature sensitivity, and C quality changes, Plant Soil<\/em>, 2014, Vol. 381. Iss. 1\u20132. \u0440\u0440. 307\u2013321.<\/span><\/p>\n

Bondareva L. G., Rubailo A. I., Novye dannye urovnya zagryazneniya aerozol\u2019nymi vypadeniyami tritiya v blizhnei zone vliyaniya gorno-khimicheskogo kombinata GK Rosatoma (New data on the level of contamination with tritium aerosol fallout in the nearest influence zone of the mining-chemical combine of the Rosatom State Corporation), Doklady akademii nauk<\/em>, 2016, Vol. 467, No 1, pp. 67\u201370.<\/span><\/p>\n

Bradford M. A., Berg B., Maynard D. S., Wieder W. R., Wood S. A., Understanding the dominant controls on litter decomposition, Journal of Ecology<\/em>, 2016, No 104, Iss. 1, \u0440\u0440. 229\u2013238.<\/span><\/p>\n

Bray J. R., Gorham E., Litter production in forests of the world, Advances in Ecological Research<\/em>, Academic Press, London, 1964, Vol. 2, pp. 101-157.<\/span><\/p>\n

Brovkin V., van Bodegom P. M., Kleinen T., Wirth C., Cornwell W. K., Cornelissen\u00a0J.\u00a0H.\u00a0C., Kattge J., Plant-driven variation in decomposition rates improves projections of global litter stock distribution, Biogeosciences<\/em>, 2012, Vol. 9, Iss. 1, pp. 565\u2013576.<\/span><\/p>\n

Bryanin S. V., Abramova E. R., Opad fitomassy v postpirogennykh listvennichnikakh Zeiskogo zapovednika (Verkhnee Priamur\u2019e) (Phytomass of litter fall in postfire larch forests of Zeisky nature reserve (Upper Priamurie)), Sibirskii lesnoi zhurnal<\/em>, 2017, No 2, pp. 93\u2013101.<\/span><\/p>\n

Chavez-Vergara B., Merino A., V\u00e1zquez-Marrufo G., Garc\u00eda-Oliva F., Organic matter dynamics and microbial activity during decomposition of forest floor under two native neotropical oak species in a temperate deciduous forest in Mexico, Geoderma<\/em>, 2014, Vol. 235-236, \u0440\u0440. 133\u2013145.<\/span><\/p>\n

Chen X., Page-Dumroese D., Lv R., Wang W., Li G., Liu Y., Interaction of initial litter quality and thinning intensity on litter decomposition rate, nitrogen accumulation and release in a pine plantation, Silva Fennica<\/em>, 2014, Vol. 48, No 4. Article 1211.<\/span><\/p>\n

Chernen\u2019kova T. V., Bochkarev Yu. N., Fridrikh M., Bettger T., Vozdeistvie prirodno-antropogennykh faktorov na radial\u2019nyi prirost derev\u2019ev Kol\u2019skogo Severa (The impact of natural and anthropogenic factors on radial tree growth on the northern Kola Peninsula), Lesovedenie<\/em>, 2012, No 4, pp. 3\u201315.<\/span><\/p>\n

Chernen\u2019kova T. V., Koroleva N. E., Borovichev E. A., Melekhin A. V.,\u2008Izmenenie organizatsii lesnogo pokrova makrosklonov k ozeru Imandra v usloviyakh tekhnogennogo zagryazneniya (Change of the forest cover on the slopes oriented towards Lake Imandra under industrial pollution), Trudy Karel\u2019skogo nauchnogo tsentra RAN<\/em>, 2016, No 12, pp. 3\u201324.<\/span><\/p>\n

Chul\u2019diene D., Aleinikoviene Yu., Murashkiene M., Marozas V., Armolaitis K., Raspad i sokhrannost\u2019 organicheskikh soedinenii i pitatel\u2019nykh elementov v listvennom opade posle zimnego sezona pod lesoposadkami listvennitsy evropeiskoi, buka obyknovennogo i duba krasnogo v Litve (Decomposition and preservation of organic compounds and nutrients in the foliar litter after the winter season under the forest plantations of european larch, european beech and red oak in Lithuania), Pochvovedenie<\/em>, 2017, No 1, pp. 53\u201363.<\/span><\/p>\n

Danilova E. G., Stepanova S. V., Pererabotka berezovogo opada s tsel\u2019yu polucheniya tovarnogo produkta (tsellyulozy) (Processing of birch litter to obtain a commercial product (cellulose)), Vestnik tekhnologicheskogo universiteta<\/em>, 2017, Vol. 20, No 7, pp. 37\u201340.<\/span><\/p>\n

Davey M. P., Berg B., Emmett B. A., Rowland P., Decomposition of oak leaf litter is related to initial litter Mn concentrations, Canadian Journal of Botany<\/em>, 2007, Vol. 85, Iss. 1, pp. 16\u201324.<\/span><\/p>\n

De Marco A., Vittozzi P., Rutigliano F. A., Virzo de Santo A. Nutrient dynamics during decomposition of four different pine litters. In: Leone V. (ed.), Lovreglio R. (ed.). Proceedings of the international workshop MEDPINE 3: conservation, regeneration and restoration of Mediterranean pines and their ecosystems<\/em>, Bari: CIHEAM, 2007, pp. 73\u201377.<\/span><\/p>\n

De Weirdt M., Verbeeck H., Maignan F., Peylin P., Poulter B., Bonal D., Ciais P., Steppe K., Seasonal leaf dynamics for tropical evergreen forests in a process-based global ecosystem model, Geoscientific Model Development<\/em>, 2012, Vol. 5, Iss. 5, pp. 1091\u20131108.<\/span><\/p>\n

Dearden, F. M., Dehlin, H., Wardle, D. A., Nilsson, M-C., Changes in the ratio of twig to foliage in litterfall with species composition, and consequences for decomposition across a long term chronosequence, Oikos<\/em>, 2006, Vol. 115, Iss. 3, pp. 453\u2013462.<\/span><\/p>\n

Derome J., Lindroos A.-J., Effects of heavy metal contamination on macronutrient availability and acidification parameters in forest soil in the vicinity of the Harjavalta Cu-Ni smelter, SW Finland, Environmental Pollution<\/em>, 1998, Vol. 99, Iss. 2, pp. 225\u2013232.<\/span><\/p>\n

Dulya O. V., Bergman I. E., Kukarskih V. V., Vorobeichik E. L., Smirnov G. Yu., Mikryukov V. S., Pollution-induced slowdown of coarse woody debris decomposition differs between two coniferous tree species, Forest Ecology and Management<\/em>, 2019, Vol. 448, pp. 312\u2013320.<\/span><\/p>\n

Dupuy J. M., Chazdon R. L., Interacting effects of canopy gap, understory vegetation and leaf litter on tree seedling recruitment and composition in tropical secondary forests, Forest Ecology and Management<\/em>, 2008, Vol. 255, pp. 3716\u20133725.<\/span><\/p>\n

Ermakova O. D. Struktura i dinamika opada listopadnykh porod v drevostoyakh severnogo makrosklona khrebta Khamar-Daban (Yuzhnoe Pribaikal\u2019e) (Structure and dynamics of deciduous trees debris forest stands of northern macroslope of Khamar-Daban ridge (South Pribaikalye)), Izvestiya Samarskogo nauchnogo tsentra RAN<\/em>, 2009, Vol. 11, No 1 (3), pp. 377\u2013380.<\/span><\/p>\n

Fang X., Zhao L., Zhou G., Huang W., Liu J., Increased litter input increases litter decomposition and soil respiration but has minor effects on soil organic carbon in subtropical forests, Plant Soil<\/em>, 2015, Vol. 392, pp. 139\u2013153.<\/span><\/p>\n

Flower-Ellis J. G. K., Litterfall in an age series of Scots pine stands: Summary of results for the period 1973\u20131983, Department of Ecology and Environmental Research, Swedish University of Agricultural Sciences<\/em>, 1985, Report 19, pp. 75-94.<\/span><\/p>\n

Fomicheva O. A., Polyanskaya L. M., Nikonov V. V., Lukina N. V., Orlova M. A., Isaeva L. G., Chislennost\u2019 i biomassa pochvennykh mikroorganizmov v starovozrastnykh korennykh elovykh lesakh severnoi taigi (Population and biomass of soil microorganisms in old-growth primary spruce forests in the northern taiga), Pochvovedenie<\/em>, 2006, No 12, pp. 1469\u20121478.<\/span><\/p>\n

Freedman B., Hutchinson T. C., Effects of smelter pollutants on forest leaf litter decomposition near a nickel\u2013copper smelter at Sudbury, Ontario, Canadian Journal of Botany<\/em>, 1980, Vol. 58, No 15, pp. 1722-1736.<\/span><\/p>\n

Guo C., Cornelissen J. H. C., Tuo B., Ci H., Yan E.-R., Non-negligible contribution of subordinates in community-level litter decomposition: Deciduous trees in an evergreen world, Journal of Ecology<\/em>, 2020, Vol. 108, Iss. 4, pp. 1713-1724.<\/span><\/p>\n

Hale B., Robertson P., Plant community and litter composition in temperate deciduous woodlots along two field gradients of soil Ni, Cu and Co concentrations, Environmental Pollution<\/em>, 2016, Vol. 212, pp. 41-47.<\/span><\/p>\n

Hilli S., Significance of litter production of forest stands and ground vegetation in the formation of organic matter and storage of carbon in boreal coniferous forests [in:] Forest condition monitoring in Finland \u2014 National report<\/em> (Eds. P. Meril\u00e4, S. Jortikka), The Finnish Forest Research Institute, 2013, URL: https:\/\/clck.ru\/dWRrT (June 21, 2021)<\/span><\/p>\n

H\u00f6gberg P., N\u00e4sholm T., Franklin O., Tamm Review: On the nature of the nitrogen limitation to plant growth in Fennoscandian boreal forests, Forest Ecology and Management<\/em>, 2017, Vol. 403, pp. 161\u2013185.<\/span><\/p>\n

Ilvesniemi H., Levula J., Ojansuu R., Kolari P., Kulmala L., Pumpanen J., Launiainen S., Vesala T., Nikinmaa E., Long-term measurements of the carbon balance of a boreal Scots pine dominated forest ecosystem, Boreal Environment Research<\/em>, Helsinki, 2009, Vol. 14, pp. 731-753.<\/span><\/p>\n

Isidorov V. A., Smolewska M., Purzy\u0144ska-Pugacewicz A., Tyszkiewicz Z., Chemical composition of volatile and extractive compounds of pine and spruce leaf litter in the initial stages of decomposition, Biogeosciences<\/em>, 2010, Vol. 7, Iss. 9, pp. 2785\u20132794.<\/span><\/p>\n

Ivanova A. E., Nikolaeva V. V., Marfenina O. E., Izmenenie tsellyulozoliticheskoi aktivnosti gorodskikh pochv v svyazi s iz\u2019\u2019yatiem rastitel\u2019nogo opada (na primere Moskvy) (Changes in the cellulolytic activity of urban soils induced by the removal of plant litter (using Moscow as an example)), Pochvovedenie<\/em>, 2015, No 5, pp. 562\u2013570.<\/span><\/p>\n

Ivanova E. A., Lukina N. V., Var\u2019irovanie massy i fraktsionnogo sostava drevesnogo opada v sosnyakakh kustarnichkovo-lishainikovykh pri aerotekhnogennom zagryaznenii (Variation of mass and fraction composition of tree litter in dwarf shrub-lichen pine forests under aerial technogenic pollution), Lesovedenie<\/em>, 2017, No 5, pp. 47\u201358.<\/span><\/p>\n

Ivanova E. A., Lukina N. V., Danilova M. A., Artemkina N. A., Smirnov V. E., Ershov V. V., Isaeva L. G., Vliyanie aerotekhnogennogo zagryazneniya na skorost\u2019 razlozheniya rastitel\u2019nykh ostatkov v sosnovykh lesakh na severnom predele rasprostraneniya (The effect of air pollution on the rate of decomposition of plant litter at the northern limit of pine forests), Lesovedenie<\/em>, 2019, No 6, pp. 533\u2013546.<\/span><\/p>\n

Johnson D., Hale B., White birch (Betula papyrifera <\/em>Marshall) foliar litter decomposition in relation to trace metal atmospheric inputs at metal-contaminated and uncontaminated sites near Sudbury, Ontario and Rouyn-Noranda, Quebec, Canada, Environmental Pollution<\/em>, 2004, Vol. 127, Iss. 1, pp. 65\u201372.<\/span><\/p>\n

Jonczak J., Parzych A., The content of heavy metals in the soil and litterfall in a beech-pine-spruce stand in northern Poland, Archives of Environmental Protection<\/em>, 2014, Vol. 40, No 4. pp. 67\u201377.<\/span><\/p>\n

Karpachevskii L. O., Voronin A. D., Dmitriev E. A., Stroganova M. N., Shoba S. A., Pochvenno-biogeotsenoticheskie issledovaniya v lesnykh biogeotsenozakh<\/em> (Soil biogeocenotic studies in forest biogeocenoses), Moscow: izd-vo Moskovskogo universiteta, 1980, 160 p.<\/span><\/p>\n

Kazimirov N. I., Morozova R. M., Biologicheskii krugovorot veshchestv v el\u2019nikakh Karelii<\/em> (The biological cycle of substances in the spruce forests of Karelia), Leningrad: Nauka, 1973, 175 p.<\/span><\/p>\n

Kiikkil\u00e4 O., Heavy-metal pollution and remediation of forest soil around the Harjavalta Cu-Ni smelter, in SW Finland, Silva Fennica<\/em>, 2003, Vol. 37, No 3, pp. 399\u2013415.<\/span><\/p>\n

Kolmogorova E. Yu., Ufimtsev V. I., Nekotorye osobennosti khimicheskogo sostava opada sosny obyknovennoi, proizrastayushchei v usloviyakh porodnogo otvala (Some peculiarities of the chemical composition of Scotch pine debris, growing under conditions of coal pit), Uspekhi sovremennogo estestvoznaniya<\/em>, 2018, No 11, Part. 2, pp. 267\u2013272.<\/span><\/p>\n

Komissarov M. A., Ogura Sh., Raspredelenie i migratsiya radiotseziya v sklonovykh landshaftakh cherez 3 goda posle avarii na AES Fukusima-1 (Distribution and migration of radiocesium in sloping landscapes three years after the Fukushima-1 nuclear accident), Pochvovedenie<\/em>, 2017, No 7, pp. 886\u2013896.<\/span><\/p>\n

Kop\u00e1\u010dek J., Cudl\u00edn P., Fluksov\u00e1 H., Ka\u0148a J., Picek T., \u0160antr\u016f\u010dkov\u00e1 H., Svoboda M., Van\u011bk D., Dynamics and composition of litterfall in an unmanaged Norway spruce (Picea abies<\/em>) forest after bark-beetle outbreak, Boreal Environment Research<\/em>, 2015, Vol. 20, No 3, pp. 305\u2013323.<\/span><\/p>\n

Kop\u00e1\u010dek J., Cudl\u00edn P., Svoboda M., Chmelikova E., Ka\u0148a J., Picek T., Composition of Norway spruce litter and foliage in atmospherically acidified and nitrogen-saturated Bohemian Forest stands, Czech Republic, Boreal Environment Research<\/em>, 2010, Vol. 15, No 4, pp. 413\u2013426.<\/span><\/p>\n

Kopylova L. Yu., Nakoplenie tyazhelykh metallov v drevesnykh rasteniyakh na urbanizirovannykh territoriyakh vostochnogo Zabaikal\u2019ya. Avtoref. diss. \u2026 kand. biol. nauk <\/em>(Peculiarities of heavy metals accumulation by woody plants in urban territories of Eastern Zabaikalie. Extended abstract of candidate\u2019s biol. sci. thesis), Ulan-Ude, 2012, 24 p.<\/span><\/p>\n

Kouki J., Hokkanen Y., Long-term needle litterfall of a Scots pine Pinus sylvestris<\/em> stand: relation to temperature factors, Oecologia<\/em>, 1992, No 89, pp. 176-181.<\/span><\/p>\n

Kozlov M., Zvereva E., Decomposition of birch leaves in heavily polluted industrial barrens: relative importance of leaf quality and site of exposure, Environmental Science & Pollution Research<\/em>, 2015, Vol. 22, Iss. 13, pp. 9943\u20139950.<\/span><\/p>\n

Krishna M. P., Mohan M., Litter decomposition in forest ecosystems: a review, Energy, Ecology and Environment<\/em>, 2017, Vol. 2, Iss. 4, pp. 236\u2013249.<\/span><\/p>\n

Kuznetsov M. A., Vliyanie uslovii razlozheniya i sostava opada na kharakteristiki i zapas podstilki v srednetaezhnom chernichno-sfagnovom el\u2019nike (Effect of decomposition conditions and falloff composition on litter reserves and characteristics in a bilberry-sphagnum spruce forest of middle taiga), Lesovedenie<\/em>, 2010, No 6, pp. 54\u201360.<\/span><\/p>\n

Kuznetsov M. A., Osipov A. F., Rastitel\u2019nyi opad kak komponent biologicheskogo krugovorota ugleroda v zabolochennykh khvoinykh soobshchestvakh srednei taigi (Plant litter as a component of the biological carbon cycle of wet coniferous communities in the middle taiga), Vestnik Instituta biologii Komi NTs Ural\u2019skogo otdeleniya RAN<\/em>, Izd-vo Instituta biologii Komi NTs UrO RAN, 2011, No 9, pp. 10\u201312.<\/span><\/p>\n

Lamppu J., Huttunen S., Relations between Scots pine needle element concentrations and decreased needle longevity along pollution gradients, Environmental Pollution<\/em>, 2003, Vol. 122, Iss. 1, pp. 119\u2013126.<\/span><\/p>\n

Larionova A. A., Kvitkina A. K., Bykhovets S. S., Lopes-de-Gerenyu V. O., Kolyagin Yu. G., Kaganov V. V., Vliyanie azota na mineralizatsiyu i gumifikatsiyu lesnykh opadov v model\u2019nom eksperimente (The contribution of nitrogen to mineralization and humification of forest litter in simulation study), Lesovedenie<\/em>, 2017, No 2, pp. 128\u2013139.<\/span><\/p>\n

Lenthonen A., Lindholm M., Hokkanen T., Salminen H., Jalkanen R., Testing dependence between growth and needle litterfall in Scots pine \u2014 a case study in northern Finland, Tree Physiology<\/em>, Heron Publishing\u2014Victoria, Canada, 2008, Vol. 28, pp. 1741-1749.<\/span><\/p>\n

Likhanova N. V., Rol\u2019 rastitel\u2019nogo opada v formirovanii lesnoi podstilki na vyrubkakh el\u2019nikov srednei taigi (The role of tree waste in the litter layer formation in cutting areas of middle taiga spruce forests), Izvestiya VUZov. Lesnoi zhurnal<\/em>, 2014, No 3, pp. 52\u201366.<\/span><\/p>\n

Liu C., Duan C., Meng X., Yue M., Zhang H., Wang P., Xiao Y., Hou Z., Wang Y., Pan Y., Cadmium pollution alters earthworm activity and thus leaf-litter decomposition and soil properties, Environmental Pollution<\/em>, 2020, Vol. 267, Article 115410.<\/span><\/p>\n

Loydi A., Lohse K., Otte A., Donath T. W., Distribution and effects of tree leaf litter on vegetation composition and biomass in a forest\u2013grassland ecotone, Journal of Plant Ecology<\/em>, 2014, Vol. 7, Iss. 3, pp. 264\u2013275.<\/span><\/p>\n

Lukina N. V. Polyanskaya L. M., Orlova M. A., Pitatel\u2019nyi rezhim pochv severotaezhnykh lesov<\/em> (Nutrient regime of soils of the north taiga forests), Moscow: Nauka, 2008, 342 p.<\/span><\/p>\n

Lukina N. V., Nikonov V. V., Biogeokhimicheskie tsikly v lesakh Severa v usloviyakh aerotekhnogennogo zagryazneniya <\/em>(Biogeochemical cycles in the Northern forest ecosystems subjected to air pollution), Apatity: Izd-vo Kol\u2019skogo nauch. tsentra RAN, 1996, Part 1, 213 p., Part 2, 192 p.<\/span><\/p>\n

Lukina N. V., Nikonov V. V., Pitatel\u2019nyi rezhim lesov severnoi taigi: prirodnye i tekhnogennye aspekty<\/em> (Nutrient status of north taiga forests: natural regularities and pollution-induced changes), Apatity: Izd-vo Kol\u2019skogo nauch. tsentra RAN, 1998, 316 p.<\/span><\/p>\n

Lukina N. V., Orlova M. A., Steinnes E., Artemkina N. A., Gorbacheva T. T., Smirnov V. E., Belova E. A., Mass-loss rates from decomposition of plant residues in spruce forests near the northern tree line subject to strong air pollution, Environmental Science and Pollution Research<\/em>, 2017, Vol. 24, Iss. 24, pp. 19874\u201319887.<\/span><\/p>\n

Lyanguzova I., Yarmishko V., Gorshkov V., Stavrova N., Bakkal I., Impact of Heavy Metals on Forest Ecosystems of the European North of Russia [in:] Heavy Metals<\/em> (eds. H. E. D. M. Saleh, R. F. Aglan), IntechOpen, 2018, p. 92.<\/span><\/p>\n

Manakov K. N., Nikonov V. V., Biologicheskii krugovorot mineral\u2019nykh elementov i pochvoobrazovanie v el\u2019nikakh Krainego Severa<\/em> (The biological cycle of minerals and soil formation in the spruce forests of the Far North), Leningrad: Nauka, 1981, 196 p.<\/span><\/p>\n

Marian F., Sandmann D., Krashevska V., Maraun M., Scheu S., Leaf and root litter decomposition is discontinued at high altitude tropical montane rainforests contributing to carbon sequestration, Ecology and Evolution<\/em>, 2017, Vol. 7, Iss. 16, pp. 6432\u20136443.<\/span><\/p>\n

McEnroe N. A., Helmisaari H.-S., Decomposition of coniferous forest litter along a heavy metal pollution gradient, south-west Finland, Environmental Pollution<\/em>, 2001, Vol. 113, Iss. 1, pp. 11\u201318.<\/span><\/p>\n

Meier I. C., Leuschner Ch., Hertel D., Nutrient return with leaf litter fall in Fagus sylvatica<\/em> forests across a soil fertility gradient, Plant Ecology<\/em>, 2005, Vol. 177, Issue 1, pp. 99\u2013112.<\/span><\/p>\n

Methods to study litter decomposition. A practical guide<\/em> (Eds. M. A. S. Gra\u00e7a, F. B\u00e4rlocher, M. O. <\/em>Gessner). Springer, 2005, 329 p.<\/span><\/p>\n

Michopoulos P., Bourletsikas A., Kaoukis K., Fluxes, stocks and availability of nitrogen in evergreen broadleaf and fir forests: similarities and differences, Journal of Forestry Research<\/em>, 2020, 8 p.<\/span><\/p>\n

Ministerstvo prirodnykh resursov i ekologii Murmanskoi oblasti<\/em> (The Ministry of Natural Resources and Ecology of the Murmansk region), Murmansk, 2015, 177 p.<\/span><\/p>\n

Mironenko L. M., Osobennosti biologicheskogo krugovorota v drevostoyakh nekotorykh lesoobrazuyushchikh porod Severnoi Evrazii: matematicheskoe issledovanie (Features of biological cycle in stands of some Northern Eurasia forming tree species: mathematical research), Pyataya natsional\u2019naya nauchnaya konferentsiya s mezhdunarodnym uchastiem <\/em>\u201cMatematicheskoe modelirovanie v ekologii<\/em>\u201d EkoMatMod-2017<\/em> (5th<\/sup> National Science Conference with International Participation \u201cMathematical Modeling in Ecology\u201d EcoMatMod-2017), Pushchino, 16\u201320 October 2017, Pushchino: IFKhiBPP RAN, 2017, pp. 125\u2013127.<\/span><\/p>\n

Moore T. R., Trofymow J. A., Prescott C. E., Fyles J., Titus B. D., CIDET working group, Patterns of carbon, nitrogen and phosphorus dynamics in decomposing foliar litter in Canadian forests, Ecosystems, 2006, Vol. 9, No 1, pp. 46\u201362.<\/span><\/p>\n

Nakazato R. K., Louren\u00e7o I. S., Esposito M. P., Lima M. E. L., Ferreira M. L., Campos R. de O. A., Rinaldi M. C. S., Domingos M., Trace metals at the tree-litter-soil- interface in Brazilian Atlantic Forest plots surrounded by sources of air pollution, Environmental Pollution<\/em>, 2021, Vol. 268, Part A, Article 115797.<\/span><\/p>\n

Nekrasova T. P., Semennye gody i problema prognoza urozhaev u khvoinykh drevesnykh porod (Seminal years and the problem of crop forecast for coniferous tree species), Trudy po lesnomu khozyaistvu,<\/em> Zapadno-sibirskii filial AN SSSR, Novosibirskoe obshchestvo NTOLesprom, 1957, Issue 3, pp. 185-191.<\/span><\/p>\n

Neumann M., Ukonmaanaho L., Johnson J., Benham S., Vesterdal L., Novotn\u00fd R., Verstraeten A., Lundin L., Thimonier A., Michopoulos P., Hasenauer H. Quantifying carbon and nutrient input from litterfall in European forests using field observations and modeling, Global Biogeochemical Cycles<\/em>, 2018, Vol. 32, No 5, P. 784\u2013798.<\/span><\/p>\n

Nieminen, T., Helmisaari H-S., Nutrient retranslocation in the foliage of Pinus sylvestris<\/em> L. growing along a heavy metal pollution gradient, Tree Physiology<\/em>, 1996, Vol. 16, Iss. 10, pp. 825\u2013831.<\/span><\/p>\n

Nieminen T.M., Derome J., Helmisaari H.-S., Interactions between precipitation and Scots pine canopies along a heavy-metal pollution gradient, Environmental Pollution<\/em>, 1999, Vol. 106, Iss. 1, pp. 129\u2013137.<\/span><\/p>\n

Nikonov V. V., Lukina N. V., Polyanskaya L. M., Panikova A. N., Osobennosti rasprostraneniya mikroorganizmov v Al-Fe-gumusovykh podzolakh severotaezhnykh elovykh lesov: prirodnye i tekhnogennye aspekty (Features of the microorganisms distribution in Al-Fe-humus podzols under northern taiga spruce forests: natural and technogenic aspects), Mikrobiologiya<\/em>, 2001, Vol. 70, No 3, pp. 319\u2013328.<\/span><\/p>\n

Nikonov V. V., Lukina N. V., Bezel\u2019 V. S., Bel\u2019skii E. A., Bespalova A. Yu., \u2026, & Yatsenko-Khmelevskaya M. A., Rasseyannye elementy v boreal\u2019nykh lesakh<\/em> (Scattered elements in boreal forests), Moscow: Nauka, 2004, 616 p.<\/span><\/p>\n

Nov\u00e1k J., Du\u0161ek D., Slodi\u010d\u00e1k M., Quantity and quality of litterfall in young oak stands, Journal of Forest Science<\/em>, 2014, Vol. 60, No 6, pp. 219-225.<\/span><\/p>\n

Ogden A. E., Schmidt M. G., Litterfall and soil characteristics in canopy gaps occupied by vine maple in a coastal western hemlock forest, \u0421<\/em>anadian Journal of Soil Science<\/em>, 1997, Vol. 77, Iss. 4, pp. 703-711.<\/span><\/p>\n

Osipov A. F., Zapasy i potoki organicheskogo ugleroda v ekosisteme spelogo sosnyaka chernichnogo srednei taigi (Stocks and fluxes of organic carbon in the ecosystem of mature bilberry pine forest of the middle taiga), Sibirskii lesnoi zhurnal<\/em>, 2017, No 2, pp. 70\u201380.<\/span><\/p>\n

Pausas J. G., Litter fall and litter decomposition in Pinus sylvestris<\/em> forests of the eastern Pyrenees, Journal of Vegetation Science<\/em>, 1997, Vol. 8, pp. 643\u2013650.<\/span><\/p>\n

Pedersen L. B., Bille-Hansen J., A comparison of litterfall and element fluxes in even aged Norway spruce, sitka spruce and beech stands in Denmark, Forest Ecology <\/em>&<\/em> Management<\/em>, 1999, Vol. 114, pp. 55\u201370.<\/span><\/p>\n

Petrochenko K. A., Kurovskii A. V., Babenko A. S., Yakimov Yu. E., Vermikompost na osnove listovogo opada \u2014 perspektivnoe kal\u2019tsievoe udobrenie (Leaf litter-based vermicompost as promising calcium fertilizer), Vestnik Tomskogo gosudarstvennogo universiteta. Biologiya<\/em>, 2015, No 2 (30), pp. 20\u201334.<\/span><\/p>\n

Polyanskaya L. M., Nikonov V. V., Lukina N. V., Panikova A. N., Zvyagintsev V. G., Mikroorganizmy Al-Fe-gumusovykh podzolov sosnyakov lishainikovykh v usloviyakh aerotekhnogennogo zagryazneniya (Microorganisms of Al-Fe-humus podzols of lichen pine forests under conditions of aerotechnogenic contamination), Pochvovedenie<\/em>, 2001, No 2, pp. 215\u2012226.<\/span><\/p>\n

Pomogaibin E. A., Pomogaibin A. V., Vliyanie derev\u2019ev roda Juglans <\/em>L. na tsellyulozorazrushayushchuyu aktivnost\u2019 pochvy v usloviyakh dendrariya botanicheskogo sada Samarskogo universiteta (Juglans <\/em>L. genus trees influence on cellulolytic soil activity in Samara University Botanical Garden Dendrarium), Samarskii nauchnyi vestnik<\/em>, 2018, Vol. 7, No 1 (22), pp. 105\u2013109.<\/span><\/p>\n

Portillo-Estrada M., Korhonen J., Pihlatie M., Pumpanen J., Frumau A., Morillas L., Tosens T., Niinemets \u00dc., Inter- and intra-annual variations in canopy fine litterfall and carbon and nitrogen inputs to the forest floor in two European coniferous forests, Annals of Forest Science<\/em>, 2013, Vol. 70, Iss. 4, pp. 367\u2013379.<\/span><\/p>\n

Portillo-Estrada M., Pihlatie M., Korhonen J. F. J., Levula J., Frumau A. K. F., Ibrom A., Lembrechts J. J., Morillas L., Horv\u00e1th L., Jones S. K., Niinemets \u00dc., Climatic controls on leaf litter decomposition across European forests and grasslands revealed by reciprocal litter transplantation experiments, Biogeosciences<\/em>, 2016, Vol. 13, pp. 1621\u20131633.<\/span><\/p>\n

Preston C. M., Bhatti J. S., Flanagan L. B., Norris C., Stocks, chemistry, and sensitivity to climate change of dead organic matter along the Canadian boreal forest transect case study, Climate Change<\/em>, 2006, Vol. 74, pp. 233\u2013251.<\/span><\/p>\n

Purahong W., Kapturska D., Pecyna M. J., Schulz E., Schloter M., Buscot F., Hofrichter M., Kr\u00fcger D., Influence of Different Forest System Management Practices on Leaf Litter Decomposition Rates, Nutrient Dynamics and the Activity of Ligninolytic Enzymes: A Case Study from Central European Forests, PLoS ONE<\/em>, 2014, Vol. 9, Iss. 4, pp. 1\u201311.<\/span><\/p>\n

Rahman M. M., Tsukamoto J., Rahman M. M., Yoneyama A., Mostafa K. M., Lignin and its effects on litter decomposition in forests ecosystems, Chemistry & Ecology<\/em>, 2013, Vol. 29, Iss. 6, pp. 540\u2013553.<\/span><\/p>\n

Rakhleeva A. A., Semenova T. A., Striganova B. R., Terekhova V. A., Dinamika zoomikrobnykh kompleksov pri razlozhenii rastitel\u2019nogo opada v el\u2019nikakh Yuzhnoi taigi (Dynamics of zoomicrobial complexes upon decomposition of plant litter in spruce forests of the southern taiga), Pochvovedenie<\/em>, 2011, No 1, pp. 44\u201355.<\/span><\/p>\n

Rautio P., Huttunen S., Lamppu J., Effects of sulphur and heavy metal deposition on foliar chemistry of Scots pines in Finnish Lapland and on the Kola Peninsula, Chemosphere<\/em>, 1998a, Vol. 36, Iss. 4, pp. 979\u2013984.<\/span><\/p>\n

Reshetnikova T. V., Lesnye podstilki kak depo biogennykh elementov (Forest litters as the biogenic element depo), Vestnik KrasGAU<\/em>, 2011, No 12, pp. 74\u201381.<\/span><\/p>\n

Rodin L. E., Remezov N. P., Bazilevich N. I., Metodicheskie ukazaniya k izucheniyu dinamiki i biologicheskogo krugovorota v fitotsenozakh<\/em> (Guidelines for the study of the dynamics and biological cycle in plant communities), Leningrad: Nauka, 1967, 145 p.<\/span><\/p>\n

Rukovodstvo po kompleksnomu monitoringu<\/em> (Integrated Monitoring Manual), Moscow: FGBU \u201cIGKE Rosgidrometa i RAN\u201d, 2013, 153 p.<\/span><\/p>\n

Salemaa M., Derome J., Helmisaari H.-S., Nieminen T., Vanha-Majamaa I., Element accumulation in boreal bryophytes, lichens and vascular plants exposed to heavy metal and sulfur deposition in Finland, Science of the Total Environment<\/em>, 2004, Vol. 324, Iss. 1\u20133, pp. 141\u2013160.<\/span><\/p>\n

Sayer E. J., Tanner E. V. J., Experimental investigation of the importance of litterfall in lowland semi-evergreen tropical forest nutrient cycling, Journal of Ecology<\/em>, 2010, Vol. 98, No 5, pp. 1052\u20131062.<\/span><\/p>\n

Sayer E. J., Using experimental manipulation to assess the roles of leaf litter in the functioning of forest ecosystems, Biological Reviews<\/em>, 2005, Vol. 80, pp. 1\u201331.<\/span><\/p>\n

Scherer-Lorenzen M., Bonilla J. L., Potvin C., Tree species richness affects litter production and decomposition rates in a tropical biodiversity experiment, Oikos<\/em>, 2007, Vol. 116, Iss. 12, pp. 2108\u20132124.<\/span><\/p>\n

Shaimardanova A. Sh., Stepanova S. V., Shaikhiev I. G., Issledovanie vozmozhnosti mnogokratnogo ispol\u2019zovaniya listovogo opada v kachestve sorbtsionnogo materiala po otnosheniyu k ionam zheleza (Study of reusability of leaf litter as a sorption material in relation to iron ions), Izvestiya VUZov. Prikladnaya khimiya i biotekhnologiya<\/em>, 2017, Vol. 7, No 7, pp. 164\u2013172.<\/span><\/p>\n

Shpakovskaya I. M., Rozhak V. P., Dinamika drevesnogo opada v lesnykh ekosistemakh Striisko-Sanskoi Verkhoviny (Ukrainskie Karpaty) (The tree litter dynamics in forest ecosystems of the Striysko-Sanskoy Verkhovyna (Ukrainian Carpathians)), Zhurnal nauchnykh publikatsii aspirantov i doktorantov<\/em>, 2014, Iss. 1, pp. 175\u2013179.<\/span><\/p>\n

Silaicheva M. V., Stepanova S. V., Izuchenie vozmozhnosti mnogokratnogo ispol\u2019zovaniya klenovogo opada v kachestve sorbtsionnogo materiala dlya ochistki model\u2019noi vody ot ionov zheleza (II) (Study of possibility of maple litter multiple use as a sorption material for purifying model water from iron (II) ions), Dostizheniya vuzovskoi nauki. Ekologiya i nauki o zemle<\/em>, 2016, No 23, pp. 230\u2013235.<\/span><\/p>\n

Slade E. M., Riutta T., Interacting effects of leaf litter species and macrofauna on decomposition in different litter environments, Basic and Applied Ecology<\/em>, 2012, Vol. 13, Iss. 5, pp. 423\u2013431.<\/span><\/p>\n

Smirnova N. V., Tiunov A. V., Nechaeva T. V., Khudyaev S. A., Kruten\u2019 V. S., Lyubechanskii I. I., Vliyanie solei natriya i zheleza na mineralizatsiyu opada berezy v inkubatsionnom eksperimente (Influence of sodium and iron salts on the mineralization of birch litter in an incubation experiment), Sb. materialov Vseross. nauch. konf. s mezhdunar. uchastiem, posvyashchennoi 110-letiyu vydayushchegosya organizatora nauki i pervogo direktora IPA SO RAN R. V. Kovaleva <\/em>\u201cPochvennye resursy Sibiri: vyzovy XXI veka<\/em>\u201d (Book of Proc. of All-Russian Science Conference with International Participation, Dedicated to the 110th<\/sup> Anniversary of the Outstanding Organizer of Science and the First Director of the IPA SB RAS R. V. Kovalev \u201cSoil Resources of Siberia: Challenges of the XXI Century\u201d), Novosibirsk, 4\u20138 December 2017, Tomsk: Izd. dom Tomskogo gosudarstvennogo universiteta, 2017, Part 1, pp. 254\u2013257.<\/span><\/p>\n

Sobachkin R. S., Kovaleva N. M., Petrenko A. E., Sobachkin D. S., Struktura goryuchikh materialov v sosnyakakh raznogo vozrasta Krasnoyarskoi lesostepi (The structure of forest fuels in variously aged pine woodlands of forest-steppe domain in Krasnoyarsk), Lesovedenie<\/em>, 2017, No 6, pp. 431\u2013436.<\/span><\/p>\n

Stavrova N. I., Vliyanie atmosfernogo zagryazneniya na semenoshenie khvoinykh porod (The impact of atmospheric pollution on seed productivity of conifers), In: Lesnye ekosistemy i atmosfernoe zagryaznenie<\/em> (Forest ecosystems and aerial pollution), Leningrad: Nauka, 1990, pp. 115-121 (200 p.)<\/span><\/p>\n

Steinnes E., Lukina N., Nikonov V., Aamlid D., R\u00f8yset O. A gradient study of 34 elements in the vicinity of a copper-nickel smelter in the Kola Peninsula, Environmental Monitoring and Assessment<\/em>, 2000, Vol. 60, Iss. 1, pp. 71\u201388.<\/span><\/p>\n

Stojni\u0107 S., Kebert M., Dreki\u0107 M., Gali\u0107 Z., Kesi\u0107 L., Tepavac A., Orlovi\u0107 S., Heavy Metals Content in foliar litter and branches of Quercus petraea <\/em>(Matt.) Liebl. and Quercus robur <\/em>L. observed at two ICP Forests monitoring plots, Southeast European forestry<\/em>, 2019, Vol. 10, No 2, pp. 151\u2013157.<\/span><\/p>\n

Sukhareva T. A., Lukina N. V., Mineral\u2019nyi sostav assimiliruyushchikh organov khvoinykh derev\u2019ev posle snizheniya urovnya atmosfernogo zagryazneniya na Kol\u2019skom poluostrove (Mineral composition of assimilative organs of conifers after reduction of atmospheric pollution in the Kola peninsula), Ekologiya<\/em>, 2014, No 2, pp. 97\u2013104.<\/span><\/p>\n

Sverguzova S. V., Sapronova Zh. A., Svyatchenko A. V., Ispol\u2019zovanie listovogo opada kashtanov dlya izvlecheniya ionov nikelya iz rastvorov (Using chestnut leaf litter to extract nickel ions from solutions), Sb. dokl. III Mezhdunar. nauch.-tekh. konf. <\/em>\u201cEnergo- i resursosberegayushchie ekologicheski chistye khimiko-tekhnologicheskie protsessy zashchity okruzhayushchei sredy<\/em>\u201d (Book of papers of the III International Scientific Conference \u201cEnergy- and resource-saving environmentally friendly chemical-technological processes of environmental protection\u201d), Belgorod, 14\u201315 November 2017, Belgorod, 2017, pp. 84\u201389.<\/span><\/p>\n

Symonds J., Morris D. M., Kwiaton M. M., Effects of harvest intensity and soil moisture regime on the decomposition and release of nutrients from needle and twig litter in northwestern Ontario, Boreal Environment Research<\/em>, 2013, Vol. 18, No 5, pp. 401\u2013413.<\/span><\/p>\n

Tarkhanov S. N., Povrezhdennost\u2019 khvoinykh drevostoev ust\u2019ya i del\u2019ty Severnoi Dviny v usloviyakh atmosfernogo zagryazneniya (Damaged coniferous forest stands of Northern Dvina mouth and deltas in conditions of atmospheric pollution), Izvestiya Samarskogo nauchnogo tsentra RAN<\/em>, 2009, Vol. 11, No 1\u20133, pp. 394\u2013399.<\/span><\/p>\n

Trap J., H\u00e4ttenschwiler S., Gattin I., Aubert M., Forest ageing: an unexpected driver of beech leaf litter quality variability in European forests with strong consequences on soil processes, Forest Ecology <\/em>and<\/em> Management<\/em>, 2013, Vol. 302, pp. 338\u2013345.<\/span><\/p>\n

Tsandekova O. L., Dinamika nakopleniya zoly v opade Acer negundo <\/em>L. v usloviyakh narushennykh poimennykh fitotsenozov (Dynamics of accumulation of ash in litter Acer negundo <\/em>L. under conditions of disturbed floodplain phytocenoses), Byulleten\u2019 nauki i praktiki<\/em>, 2018, Vol. 4, No 12, pp. 148\u2012152.<\/span><\/p>\n

Tsvetkov V. F., Tsvetkov I. V., Les v usloviyakh aerotekhnogennogo zagryazneniya<\/em> (Forest in conditions of aerial technogenic pollution), Arkhangel\u2019sk, 2003, 354 p.<\/span><\/p>\n

Tsvetkov V. F., Tsvetkov I. V., Promyshlennoe zagryaznenie okruzhayushchei sredy i les<\/em> (Industrial pollution of environment and forest), Arkhangel\u2019sk: IPTs SAFU, 2012, 312 p.<\/span><\/p>\n

Tu L-h., Hu H-l., Chen G., Peng Y., Xiao Y-l., Hu T-x., Zhang J., Li X-w., Liu L., Tang Y., Nitrogen addition significantly affects forest litter decomposition under high levels of ambient nitrogen deposition, PLoS ONE<\/em>, 2014, Vol. 9, Iss. 2. P. 1\u20139.<\/span><\/p>\n

\u0164upek B., M\u00e4kip\u00e4\u00e4 R., Heikkinen J., Peltoniemi M., Ukonmaanaho L., Hokkanen T., N\u00f6jd P., Nevalainen S., Lindgren M., Lehtonen A., Foliar turnover rates in Finland \u2014 comparing estimates from needle-cohort and litterfall-biomass methods, Boreal Environment Research<\/em>, 2015, Vol. 20, No 2, pp. 283\u2013304.<\/span><\/p>\n

Ufimtsev V. I., Egorova I. N., Rol\u2019 rastitel\u2019nogo opada v formirovanii fitogennykh polei sosny obyknovennoi na tekhnogennykh elyuviyakh Kuzbassa (Role of the vegetable debris in formation of phytogenous fields of the scots pine on technogenic eluviums of Kuzbass), Uspekhi sovremennogo estestvoznaniya<\/em>, 2016, No 4, pp. 116\u2013120.<\/span><\/p>\n

Ukonmaanaho L., Merila P., N\u00f6jd P., Nieminen T. M., Litterfall production and nutrient return to the forest floor in Scots pine and Norway spruce stands in Finland, Boreal Environment Research<\/em>, 2008, Vol. 13 (suppl. B), pp. 67\u201391.<\/span><\/p>\n

Ukonmaanaho L., Pitman R., Bastrup-Birk A., Breda N., Rautio P., Manual on methods and criteria for harmonized sampling, assessment, monitoring and analysis of the effects of air pollution on forests In: Part XIII: Sampling and Analysis of Litterfall<\/em>, UNECE ICP Forests Programme Co-ordinating Centre, Eberswald, 2016, 15 p.<\/span><\/p>\n

Vacek S., Vacek Z., B\u00edlek L., Simon J., Reme\u0161 J., H\u016fnov\u00e1 I., Kr\u00e1l J., Putalov\u00e1 T., Mikeska M., Structure, regeneration and growth of Scots pine (Pinus sylvestris <\/em>L.) stands with respect to changing climate and environmental pollution, Silva Fennica<\/em>, 2016, Vol. 50, No 4, Article 1564.<\/span><\/p>\n

Van Nevel L., Mertens J., Demey A., De Schrijver A., De Neve S., Tack F. M. G., Verheyen K., Metal and nutrient dynamics in decomposing tree litter on a metal contaminated site, Environmental Pollution<\/em>, 2014, Vol. 189, pp. 54-62.<\/span><\/p>\n

Vavrova P., Penttila T., Laiho R., Decomposition of Scots pine fine woody debris in boreal conditions: Implications for estimating carbon pools and fluxes, Forest Ecology and Management<\/em>, 2009, Vol. 257, Iss. 2, pp. 401\u2013412.<\/span><\/p>\n

Vedrova E. F., Reshetnikova T. V., Massa podstilki i intensivnost\u2019 ee razlozheniya v 40-letnikh kul\u2019turakh osnovnykh lesoobrazuyushchikh porod Sibiri (Litter mass and intensity of litter decomposition in 40-year old plantations of the main forest forming species of Siberia), Lesovedenie<\/em>, 2014, No 1, pp. 42\u201350.<\/span><\/p>\n

Vesterdal L., Elberling B., Christiansen J. R., Callesen I., Schmidt I. K., Soil respiration and rates of soil carbon turnover differ among six common European tree species, Forest Ecology <\/em>and <\/em>Management<\/em>, 2012, Vol. 264, pp. 185\u2013196.<\/span><\/p>\n

Vorobeichik E. L., Pishchulin P. G., Promyshlennoe zagryaznenie snizhaet rol\u2019 derev\u2019ev v formirovanii struktury polei kontsentratsii tyazhelykh metallov v lesnoi podstilke (Industrial pollution reduces the effect of trees on forming the patterns of heavy metal concentration fields in forest litter), Ekologiya<\/em>, 2016, No 5, pp. 323\u2013334.<\/span><\/p>\n

Vorobeichik E. L., Pishchulin P. G., Vliyanie otdel\u2019nykh derev\u2019ev na pH i soderzhanie tyazhelykh metallov v lesnoi podstilke v usloviyakh promyshlennogo zagryazneniya (Effect of individual trees on the pH and the content of heavy metals in forest litters upon industrial contamination), Pochvovedenie<\/em>, 2009, No 8, pp. 927\u2013939.<\/span><\/p>\n

Vorobeichik E. L., Pishchulin P. G., Vliyanie derev\u2019ev na skorost\u2019 destruktsii tsellyulozy v pochvakh v usloviyakh promyshlennogo zagryazneniya (Effect of trees on the decomposition rate of cellulose in soils under industrial pollution), Pochvovedenie<\/em>, 2011, No 5, pp. 597\u2013610.<\/span><\/p>\n

Vorobeichik E. L., Trubina M. R., Khantemirova E. V., Bergman I. E., Mnogoletnyaya dinamika lesnoi rastitel\u2019nosti v period sokrashcheniya vybrosov medeplavil\u2019nogo zavoda (Long-term dynamic of forest vegetation after reduction of copper smelter emissions), Ekologiya<\/em>, 2014, No 6, pp. 448\u2013458.<\/span><\/p>\n

Vorob\u2019eva I. G., Naumova A. N., Intensivnost\u2019 protsessa destruktsii rastitel\u2019nogo opada v pochvakh sukhikh mestoobitanii (Intensity of waste degradation in dry habitat soils), III international forest soil science conference: Productivity and resistance of forest soils<\/em>, Proc. Conf., Petrozavodsk, 7\u201211 September, 2009, pp. 192\u2013195.<\/span><\/p>\n

Wardle D. A., Nilsson M.-C., Zackrisson O., Gallet C., Determinants of litter mixing effects in a Swedish boreal forest, Soil Biology and Biochemistry<\/em>, 2003, Vol. 35, Iss. 6, pp. 827\u2013835.<\/span><\/p>\n

Wood T. E., Lawrence D., Clark D. A., Determinants of leaf litter nutrient cycling in a tropical rain forest: soil fertility versus topography, Ecosystems<\/em>, 2006, No 9, pp. 700\u2013710.<\/span><\/p>\n

Wood T. E., Lawrence D., Clark D. A., Chazdon R. L., Rain forest nutrient cycling and productivity in response to large-scale litter manipulation, Ecology<\/em>, 2009, Vol. 90, No 1, pp. 109\u2013121.<\/span><\/p>\n

Xu S., Liu L. L., Sayer E. J., Variability of above-ground litter inputs alters soil physicochemical and biological processes: a meta-analysis of litterfall-manipulation experiments, Biogeosciences<\/em>, 2013, Vol. 10, Iss. 11, pp. 7423\u20137433.<\/span><\/p>\n

Yarmishko V. T., Lyanguzova I. V., Mnogoletnyaya dinamika parametrov i sostoyaniya khvoi Pinus sylvestris<\/em> L. v usloviyakh aerotekhnogennogo zagryazneniya na Evropeiskom Severe (Long-term dynamics of parameters and state of Pinus sylvestris<\/em> L. needles in the conditions of aerial technogenic pollution in the European North), Izvestiya SPbLTA<\/em>, Saint-Petersburg: SPbGLTU, 2013, No 2 (203), pp. 30-46.<\/span><\/p>\n

Yavitt J. B., Williams C. J., Conifer litter identity regulates anaerobic microbial activity in wetland soils via variation in leaf litter chemical composition, Geoderma<\/em>, 2015, Vol. 243\u2013244. pp. 141\u2013148.<\/span><\/p>\n

Yusupov I. A., Zalesov S. V., Shavnin S. A., Luganskii N. A., Osobennosti dinamiki i struktury drevesnogo opada v sosnovykh molodnyakakh v zone deistviya aeropromvybrosov na Srednem Urale (Features of the dynamics and structure of tree litter in young pine stands in the area of air pollution in the Middle Ural), Lesa Urala i khozyaistvo v nikh: sb. nauch. tr<\/em>., 1995, Iss. 18, pp. 59\u201374.<\/span><\/p>\n

Zaboeva I. V., Pochvy i zemel\u2019nye resursy Komi ASSR<\/em> (Soils and land resources of Komi ASSR), Syktyvkar: Komi kn. izd-vo, 1975, 344 p.<\/span><\/p>\n

Zenkova I. V., Struktura soobshchestv bespozvonochnykh zhivotnykh v lesnykh podzolakh Kol\u2019skogo poluostrova. Diss. kand. biol. nauk<\/em> (The structure of invertebrate communities in the forest podzols of the Kola Peninsula. Candidate\u2019s biol. sci. thesis), Apatity, 2000, 156 p.<\/span><\/p>\n

Zhang D., Hui D., Luo Y., Zhou G., Rates of litter decomposition in terrestrial ecosystems: global patterns and controlling factors, Journal of Plant Ecology<\/em>, 2008, Vol. 1, Iss. 2, pp. 85\u201393.<\/span><\/p>\n

\u00a0<\/strong><\/span><\/p>\n

 <\/p>\n

Reviewer: <\/strong>Candidate of Biological Sciences F. I.\u00a0Zemskov<\/span><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

Original Russian Text \u00a9 2021 E. A. Ivanova published in Forest Science Issues Vol. 4, No. 3,\u00a0\u00a0Article 87 E. A. Ivanova Institute of North Industrial Ecology Problems KSC RAS Akademgorodok st. 14a, Apatity, Murmansk...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[24],"tags":[],"_links":{"self":[{"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/posts\/5000"}],"collection":[{"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/comments?post=5000"}],"version-history":[{"count":3,"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/posts\/5000\/revisions"}],"predecessor-version":[{"id":5004,"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/posts\/5000\/revisions\/5004"}],"wp:attachment":[{"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/media?parent=5000"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/categories?post=5000"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jfsi.ru\/en\/wp-json\/wp\/v2\/tags?post=5000"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}