High species richness in hemiboreal forests of the northern Russian Altai, southern Siberia
Journal
Journal of Vegetation Science
Journal Volume
23
Journal Issue
4
Pages
605-616
Date Issued
2012
Author(s)
Chytrý, M.
Abstract
Questions: We discovered forests with very high local numbers of vascular plant species in southern Siberia. Are these the most species-rich forests of the Eurasian boreal and temperate zones, and which factors cause such high species richness? Location: Altai Mountains in southern Siberia, Altai Republic, Russia. Methods: We sampled vegetation and measured environmental variables across the Altai Mountains in plots of 100 m2 and established series of nested plots of the size from 1 to 1000 m2 at sites with the highest species richness. We compared the richest forests with other forests of the Altai and with literature records of species-rich vegetation types from elsewhere. Results: The richest forests contained 45 vascular plant species per 1 m2, 82 per 10 m2, 114 per 100 m2 and 149 per 1000 m2. They are open hemiboreal forests dominated by Pinus sylvestris, with an admixture of Betula pendula, and sparse shrub and moss layers. About 95% of their vascular plant species are in the herb layer. All species are native. These forests occur in a forest-steppe landscape of the northern Altai, where the mean January temperature is between -12.5 and -10 °C, mean July temperature is 16-18 °C, and total annual precipitation is 560-610 mm. Soils are deep and mesic, with a pH of 6.2-6.4. Conclusions: Hemiboreal forests of the northern Russian Altai are probably the most species-rich forests in boreal and temperate Eurasia. Such a high concentration of many species in small plots probably results from the incidental combination of several factors conducive to high species richness. These factors include the rich regional flora of the Altai Mountains, stability of the environment of this region since the Pleistocene, heterogeneity of the mountainous forest-steppe landscape with a combination of forested areas on north-facing slopes and steppes on south-facing ones, an open canopy that ameliorates microclimate conditions but does not exclude light-demanding species through strong shading, a macroclimate that is not too harsh, mesic soils with near-neutral pH, and limited competition. © 2012 International Association for Vegetation Science.
Subjects
Alpha diversity; Betula pendula; Biodiversity; Forest-steppe; Herb layer; Pinus sylvestris; Vascular plants; Woodland
Other Subjects
boreal forest; heterogeneity; pH; plant community; Pleistocene; species richness; steppe; temperature effect; vascular plant; vegetation structure; woodland; Altai Mountains; Altay [Russian Federation]; Russian Federation; Betula pendula; Bryophyta; Pinus sylvestris; Tracheophyta
Type
journal article