Abstract:

The relationship between leaf and stem capacitance of Populus×euramericana 'Neva' and its physiological index was studied. The results showed that the leaf capacitance had significant positive correlations with leaf exosmosis electro_ conductivity, exosmosis percentage and leaf absolute moisture content, had significant negative correlations with leaf electrolyte electroconductivity and had no correlations with leaf relative water content (RWC); the stem capacitance had significant positive correlations with DBH(diameter at breast height) and bark relative turgidity (RT). The conception of `unit capacitance' was proposed. There were evident differences between health and debility trees in stem capacitance and unit capacitance. So the research of the leaf, stem and unit capacitance would provide a theoretical basis for the quantitative assessment of the degree of damage and lack of water of trees, the ability of disease-resistance, tree vigor and stands growth condition.

Key words: tree capacitance, electroconductivity, unit capacitance, tree vigor