INDICATORS OF WATER EXCHANGE OF LEAVES OF OAK QUERCUS ROBUR L. AND QUERCUS RUBRA L. IN VARIOUS GROWING CONDITIONS IN THE NORTHERN SUBZONE OF THE STEPPE OF UKRAINE

Abstract

Water metabolism indicators of leaves Q. robur and Q. rubra in artificial planting and trees at a distance from him wascompared . Found that the leaves Q. robur of separately growing trees is characterized by predominantly higher intensity of transpiration in all months of the study than Q. rubra. Planting both types in the vast majority of measurements of water evaporation is less significant than in the separately growing trees in a clearing. Noted that in September, the figures of evaporation of water is the highest relative to the previous time of measurement. Was observed the fall of this indicator in the hottest period of the day, as in July, indicating deterioration of the water loss regulation. The Q. robur leaf water deficit in plants of open space is bigger than in planting in all studied periods. In Q. rubra, the figure bigger in the planting. A comparison of leaves water deficit both species separately growing trees indicates that it is smaller in Q. rubra than in Q. robur, it is consistent with a more intense return of water by Q. robur leaves. But planting despite more intense transpiration and lower water-holding capacity from Q. robur has conversely situation. During all periods of the study water-storage capacity is higher in the Q. rubra leaves than in Q. robur. However, the relative turgescence in Q. robur leaves the highest in the plantations, in Q. rubra this figure the biggest in separately growing trees, which can be explained by the fact that this indicator depends not only from evaporation, but also to a large extent on the flow of water through the root system.