讲座题目：Vitality assessment of trees and the influence of ageing processes

主讲人：Andreas Roloff 教授

主持人：达良俊 教授

开始时间：2018-10-29（周一）下午13：30

讲座地址：闵行校区 生科辅楼119

主办单位：生态与环境科学学院 科技处

报告人简介：

       Andreas Roloff，德国德累斯顿工业大学林学院和建筑学院园林系教授，1986年哥根廷大学林学系获博士学位，后在哥廷根大学林业植物研究所、哥廷根大学林科院工作，1994年起，任德累斯顿工业大学林学院教学院长、 建筑学院园林系教授。

报告内容简介: 

       In this presentation general methodical problems of vitality assessments of deciduous trees are discussed; existing disparities or contradictions are pointed out if assessments based on 'leaf loss' and based on crown structures are compared. The necessity of considering the branching pattern is substantiated and the methods developed to date are presented.
       With the help of the 'shoot base scars', it becomes possible to reconstruct the crown development of the last 10 years, and in some species of decades. In every investigated (broad leaved) tree species there are four growth stages to discriminate: exploration, degeneration, stagnation, and resignation. These stages, which result in fundamental modifications of the branching structure, are due to (statistically significant) decreasing shoot lengths. Especially in the leafless state these different branching structures in the treetop are perceived from a distance (and in aerial photographs, as well). They are the basis of vitality assessment in four vitality classes.
      By using this approach which is based on branching structures a long-term chronic decrease of vitality can be recognized. Therefore, it is a practical method to use in detecting stress and decline in urban and forest trees. This method has been tested and confirmed in many studies and is now used in European countries for urban and forest tree assessment.
      To interpret the results of vitality assessment correctly, the tree age has to be taken into consideration. A proposal for this approach is demonstrated.
In ideal examples, 10 life stages can be identified in very long-lived tree species. In order to make it easier to account for the essential factor of a tree's age when assessing the tree's vitality, tree species should be differentiated into three groups: SL: short-lived (< 100 ys.), ML: medium long-lived (150 to 300 ys.), LL: long-lived species (> 400 ys.).