Vegetation-environment Relationships within and among Selected Natural Forests in North Korea

Abstract

The set of 234 forest vegetation samples from North Korean forests was subdivided into two homogenous groups, i.e. coniferous forests, and broad-leaved and mixed forests. The indirect (i.e. the detrended correspondence analysis, DCA) and direct (i.e. canonical correspondence analysis, CCA) gradient analyses were used to recognize relationships between forest communities and several environmental variables (mean annual precipitation, slope orientation and inclination, altitude, cover of particular forest strata, mean annual Kira’s warmth (WI) and coldness (CI) indices). Although relatively little variation in species composition is explained by the indirect ordination, environmental gradients were recognizable in both mountain coniferous forests and mixed pine-oak forests. Altitude and precipitation, and their interdependence, seem to be good predictors of forest composition, particularly in the mountain coniferous forests. In fact, these variables generally are the most important factors affecting species distribution and vegetation zonation along environmental gradients. Nevertheless, understanding the ecology of these forest ecosystems will not be complete without investigation of the effects of other biotic and abiotic factors, such as latitude, distance from the sea, air humidity, prevailing wind direction, temperature, light intensity, evapotranspiration, soil features and various kinds of natural and human-caused disturbances. This is an area for future research in the region. The change in species diversity (Hill’s index) did not show any distinct pattern in relation to any environmental gradient. This is true across the whole data set and within the two main forest types.