Growth features of Arbutus andrachne L. under the conditions of field vegetation experiment on the Southern Coast of the Crimea

Abstract

The dependence of the growth rate of Arbutus andrachne L. on some environmental factors was studied under the conditions of the Southern Coast vegetation experiment in different periods of the species vegetation, which made it possible to find the optimal and limiting conditions for its growth. In March, vegetation began at an average daily air temperature of 3.5 – 7.50 °C and the increase in stem diameter was approximately 0.42 % (0.09 mm), at the second stage (April-May) – 3.7 % (0.58 mm) with a further exit to plateau. In July - August, two sections of the d % change are observed: the first section is from July 27 till August 19 - intensive growth of d % by 12.58 % (1.961 mm), the second section after August 19 – access to the growth plateau, which is associated with an increase in air temperature to 30-35 °C. In September-October, two sections of the d % change are observed: the first section lasted from September 01 till September 15 - intensive growth of d % by 3.55 % (0.582 mm), the second section after September 15 – exit to a plateau of growth, lowering the air temperature to 8-10 °C and the end of the growing season. In November, an increase in trunk diameter was not observed. The optimal environmental factors were: in March-May, Ta = 20-2 °C, Da = 0.4-1.2 kPa, I = 300-900 mmol / m2s; July-August, Ta = 22-28 °C, Da = 1.4-2.5 kPa, I = 500-1000 μmol / m2s; in September-October, Ta = 16-25 °C, Da = 0.3-1.5 kPa, I = 400-800 μmol / m2s, respectively. The results of our experiments allow us to compare the ecological and physiological characteristics we obtained with the climatic conditions of a particular region and evaluate the possibilities of introducing it into other regions.