Морфологические показатели крон лещины в горных лесах

Abstract

Common hazel is valuable for its nutritional and medicinal properties and its ability to provide soil conservation functions. However, the morphological characteristics of this plant have not been studied sufficiently. The research purpose is to identify features of significant morphological characteristics of crowns of nut-bearing hazel plants, to assess the biological diversity of these characteristics at different heights, under the forest canopy and on the glades for further detection of forestry and ecological functions of this plant, and to select ornamental and other economically valuable forms. The nut-bearing hazel plants growing in the mountain forests of the North-Western Caucasus at the altitude of 450–600 and 1,300–1,500 m above the sea level under the forest canopy and on the glades were the objects of the research. We studied the diameters of the central and three largest trunks, the crown and the base of the bush, its height, the number of shoots up to 4 years old and older, the total number of shoots in the bush, the density and shape of the crown. We examined 200 ramets that had entered the fruiting stage. The diversity index was calculated according to the authors’ method (Sukhorukikh-Biganova). At the altitudes of 1,300–1,500 m above the sea level, under better humidification compared to the sites located at the altitude of 450–600 m, hazel has statistically reliable better development of average diameters of the central and three main trunks and crown, higher total number of shoots up to 4 years old and older. Hazel trees have superior crown and bush base diameters, greater number of shoots up to 4 years old and older, the total number of shoots in the bush on the glades in conditions of good light compared to those under the forest canopy. Here the plants are more likely to form bushes with a spreading and thick crown. The upper sites showed a significantly higher diversity index for the average diameter of the three largest trunks of the hazel bush and the highest number of shoots older than 4 years. There is a significantly superior difference in the morphological diversity index for the average diameter of the bush base, the number of shoots up to 4 years old and older, the total number of shoots, and crown density on the glades compared to the sites under the forest canopy. In terms of crown shape, the diversity index is higher under the forest canopy than on the glade. The generalized indices of diversity of quantitative, qualitative and general morphological characteristics of hazel bushes did not differ significantly at different heights, under forest canopy and on the glades.