CHANGES IN THE STRUCTURE AND DIVERSITY OF PLANT SPECIES FORMED BY RED OAK (QUERCUS RUBRA .L) IN DZIRMIŠKĖS FOREST IN 2010-2020

Abstract

Red oak (Quercus rubra L.) is planted in Lithuanian forests in many places. A significant part is in the Alytus regional subdivision, in the areas of Dzirmiškės forest district. The last data collected and research carried out was in 2010, so the data collected and analyzed in 2020 will be compared with previous data and changes in the structure and diversity of plant species formed by red oak stands after 10 years will be assessed. During the study, 6 red oak plots were measured, 2 plots in each plot. The species composition of stand groves, the composition and density of undergrowth and ravines, changes in grass and moss cover and their frequency were determined. During 10 years, the tree species composition of the red oak studied forests did not change, the average height increased by 1.9 m and the diameter by 4.5 cm. The red oak undergrowth were mostly found in the red oak forest, and their density increased significantly over 10 years. After 10 years, changes in the species of herbaceous vegetation were observed in the red oak stands: the incidence of common dandelion, giant fescue, european goldenrod decreased. Changes in moss species have also been identified: many-fruited thyme-moss and the hart's-tongue thyme-moss were gone. Over a period of 10 years, the diversity and density of herbaceous species decreased due to an increase in the density of red oak self-seedlings and the density of red oak tree crowns.