Syntaxonomy of plant communitiesat the quarriesafter the cuttingsof lichen and green mosspine forests(middle taiga subzone of the European North-East of Russia)
Authors: Likhanova I. A. , Shushpannikova G. S. , Zheleznova G. V. , Pystina T. N. 
Published: December 2020

Plant communities of sandy (quarry 3 — 62°05ʹ26ʺ N, 48°43ʹ56ʺ E; 6 — 61°57ʹ35ʺ N, 50°36ʹ22ʺ E) and sandy loam (1 — 62°06ʹ28ʺ N, 48°48ʹ48ʺ E; 2 — 62°06ʹ19ʺ N, 48°48ʹ42ʺ E; 4 — 62°04ʹ36ʺ N, 48°34ʹ55ʺ E; 8d — 61°44ʹ00ʺ N, 50°39ʹ05ʺ E) quarries and the surrounding lichen and green-moss pine forests quarries are charaterized. The research has been performed in the middle taiga subzone of the European North-East of Russia. Floristic classification (Braun-Blanquet, 1964) was made for 91 relevés. The Ellenberg ecological values (Ellenberg, 1974) were used to assess moisture (F), acidity (R) and nitrogen content (N). Ordination was made by NMS approach using ExcelToR software. Plant communities of renewing and young pine stands at the quarries as well as of surrounding middle aged and mature stands are assigned to the alliance Cladonio stellaris–Pinion sylvestris Kielland-Lund ex Ermakov et Morozova 2011 order Pinetalia sylvestris Oberdorfer 1957 class Vaccinio-Piceetea Br.-Bl. in Br.-Bl. et al. 1939 (Ermakov, Morozova, 2011) while communities of meadow succession stage to the union Cynosurion cristati Tx. 1947 order Arrhenatheretalia elatioris class Molinio-Arrhenatheretea Tx. 1937 (Mirkin, Naumova, 2012). Five associations, two subassociations, one variants, two subvarants and one community are established within two classes (among these, two associations. one variants, two subvariants and one community are new). Community Polytrichum piliferum (Table 3, rel. 1–7). DS: Ceratodon purpureus, Cladonia subulata, C. fimbriata, Niphotrichum canescens, Polytrichum piliferum, Salix acutifolia. These are pioneer communities at the second decade stage of succession on sandy substrate. (quarry 3) with recovering Pinus sylvestris tree layer, absence of herb-dwarf shrub layer and. presence of pioneer mosses (Polytrichum piliferum, Ceratodon purpureus), algal crusts, and lichen thalli of Cladonia, Peltigera, and Stereocaulon. Number of species — 32 (13–20). Ass. Polytricho piliferi–Pinetum sylvestris ass. nov. hoc loco (Table 3, rel. 8–30; nomenclature type (holotypus hoc loco) — rel. 18; Fig. 4). DS: Ceratodon purpureus, Cladonia gracilis ssp. turbinata, C. fimbriata, C. subulata, C. verticillata, Niphotrichum canescens, Peltigera malacea, Polytrichum piliferum, Salix acutifolia, Stereocaulon tomentosum. These are renewing pine forests at 3rd and 5th decades of succession with ground cover dominated by pioneer mosses and lichens in sandy quarries 3 and 6, and in the most drained habitats of sandy loam quarries 1, 2, 4 (slopes). Pine canopy density is 0.1–0.3, its height — 3–6 m. Herb-dwarf shrub layer is scarce (1– 10 %), that of moss-lichen is of 20–80 %. Number of species — 111 (27–45). Subass. Deschampsio–Agrostietum tenuis typicum Turubanova 1986. D S : Agrostis tenuis, Deschampsia cespitosa, Galium mollugo, Hieracium umbellatum, Leucanthemum vulgare, Pimpinella saxifraga, Stellaria graminea. These are communities of short meadow succesion stage at the sandy loam quarries 1, 2, 4, 8d. Unlike meadows of abandoned lands and pastures, described by L. P. Turubanova (1986) as subass. Deschampsio–Agrostietum tenuis typicum, the communities on technogenic habitats have lower abundance of meadow species and higher diversity of synanthropic and xerophylous species, as well as tree invasion. This is a reason to establish variant Calamagrostis epigeios (Table 4, Fig. 5) within the subass. typicum. Its DS: Betula pendula/pubescens, Calamagrostis epigeios, Ceratodon purpureus, Chamaenerion angustifolium, Erigeron acris, Pinus sylvestris, Tussilago farfara. Multispecies herb layer is mainly formed by meadow species and weeds (20–80 %). PC of moss layer — 1–50 %. Number of species — 103 (30–41). Duration of meadow stage is responsible for differences between subvariants Amoria hybrida and Trifolium medium. Ass. Polytricho juniperini–Pinetum sylvestris ass. nov. hoc loco (Table 5, nomenclature type (holotypus hoc loco) — rel. 9; Fig. 6). D S : Agrostis tenuis, Amoria repens, Brachythecium salebrosum, Orthilia secunda, Peltigera didactyla, Polytrichum juniperinum, Pyrola media, Trifolium medium, Vicia sepium. These communities are young pine stands at the third decade of succession on sandy loam in quarries 1, 2, 4, 8d. Canopy density of pines — 0.4–0.8, height — 4–8 m. There is a lot of species typical for meadow succession stage in scarce herb layer (5–40 %). as well as an occurrence of forest dwarf shrubs, and few species indicative to ass. Linnaeo borealis–Pinetum sylvestris. Moss-lichen layer (10–60 %) is formed by pioneer species and forest mosses. Number of species — 137 (27–67). NMS-ordination (Fig. 7) and data on substrate preferences of syntaxa as well as information about the duration of recovery process is the reason to built a scheme of vegetation succession in quarries in place of reduced pine trees after the cutting of lichen and green moss pine forests (Fig. 8). Series 1. Community Polytrichum piliferum (F 4.1, N 3.5, R 3.8) → ass. Polytricho piliferi–Pinetum sylvestris (F 4.1, N 3.5, R 4.1) → ??? → subass. Cladonio arbusculae–Pinetum sylvestris typicum (F 3.8, N 2.5, R 2.4). Series 2. Subvar. Amoria hybrida var. Calamagrostis epigeios subass. Deschampsio–Agrostietum tenuis typicum (F 4.4, N 4.8, R 5.4) → subvar. Trifolium medium var. Calamagrostis epigeios subass. Deschampsio–Agrostietum tenuis typicum (F 4.7, N 4.6, R 4.9) → асс. Polytricho juniperini–Pinetum sylvestris (F 4.5, N 3.9, R 4.3) → ??? → ass. Linnaeo borealis–Pinetum sylvestris (F 4.3, N 3.1, R 2.8). Additional studies are necessary to reveal the duration of succession period and intermediate stages of transition from ass. Polytricho piliferi–Pinetum sylvestris and Polytricho juniperini–Pinetum sylvestris to ass. Cladonio arbusculae–Pinetum sylvestris and Linnaeo borealis–Pinetum sylvestris. Thus, the restoration of lichen pine forests of subass. Cladonio arbusculae–Pinetum sylvestris typicum at sandy quarries passes through the stage of pine forests of ass. Polytricho piliferi–Pinetum sylvestris, which is preceded by pioneer vegetation of сommunity Polytrichum piliferum. The restoration of green moss pine forests (ass. Linnaeo borealis–Pinetum sylvestris) at sandy loam quarries passes through the stage of young pine stands (ass. Polytricho juniperini–Pinetum sylvestris), which is preceded by meadows of subvariantas Amoria hybrida and Trifolium medium var. Calamagrostis epigeios subass. Deschampsio–Agrostietum tenuis typicum.