Сообщества кедрового стланика (Pinus pumila (Pall.) Regel) полуострова Камчатка

Abstract

The detailed geobotanical characteristic of Siberian dwarf-pine (Pinus pumila (Pall.) Regel) communities of the Kamchatka Peninsula is presented. The ecologo-phytocoenotical classification based on 379 relevés has been elaborated using the main principles and classification methods of Russian geobotanical school approach. As the result 15 associations, 4 subassociations and 32 variants included into 9 association groups were revealed. The peculiarities of their species composition, community structure, ecology and geographical distribution were characterized. With the use of ecological scales 8 types of sites were recognized. Syntaxons revealed were ordinated in complex axes using V. N. Sukachov ordination approach. It was shown that mesophytic moss-rich dwarf-pine shrubs (ass. Pinetum pumilae hylocomiosum) were closely connected to the mean values of soil moisture and soil fertility of sites. They were met at the altitude 600—700 m above the sea level (a.s.l.). Rhododendron-rich dwarf-pine communities (ass. Pinetum pumilae rhododendrosum aurei) adjoined them but they were usually distributed on the higher altitudes (800—950 m a.s.l.). The driest and poorest sites at the upper border of dwarf-shrub altitudinal belt (950—1100 m a.s.l.) were occupied by lichen-rich dwarf-pine shrubs (ass. Pinetum pumilae cladinosum). The dwarf-shrub-rich Siberian dwarf-pine communities (ass. group Pineta pumilae fruticulosa) were closely connected to rather dry and poor sites. The herb and dwarf-shrub-rich dwarf-pine shrubs (ass. Pinetum pumilae herboso-fruticulosum) were connected to loose sandy volcanic soils and they were usually met on the volcanic plateaus (at the altitude 800—950 m a.s.l.). The moss and dwarf-shrub rich dwarf-pine shrubs (ass. Pinetum pumilae hylocomioso-fruticulosum) were met in sites with mean values of soil moisture and richness but they were distributed at higher altitudes (700—900 m a.s.l.) than short-herb-rich (ass. Pinetum pumilae nanoherbosum), horsetail-rich (ass. Pinetum pumilae equisetosum sylvatici) and meadowsweet-rich (ass. Pinetum pumilae spiraeosum beauverdianae) dwarf-pine communities (200—600 m a.s.l.). In the rather moist and mesotrophic sites rowan-shrub-rich (ass. Pinetum pumilae sorbosum sambucifoliae) and pine purple grass-rich (ass. Pinetum pumilae calamagrostidosum langsdorffii) were met. The moistest and richest sites were occupied by tall fern-rich (ass. group Рineta рumilae pteridosa) Siberian dwarf-pine communities. They were considered to be very rare in Kamchatka. In the wet sites with the flowing groundwater sphagnum-rich dwarf-pine communities (ass. Pinetum pumilae sphagnosum girgensohnii) were met. They were closely connected to the steep slopes of rivulet valleys. Cloudberry-rich dwarf-pine shrubs (ass. Pinetum pumilae chamaemori-rubosum) adjoined them but they were mainly distributed on the relic peats of the Karaginsky Island.