Trends in fore schwach geschadig s126% Main causes of defoliaton Biological causes:insects/disease/livestock Mechanical damage 4.Air pollution:emissions and effluents into the ai soil and water degrades the environment and pton-lg TREE GROWTH ZONES R8a 22 Trends in forest defoliation in Europe for the period 1992 to 2003 efoliation of crown cover Proportion of trees with >25% d www.fao.org/docrep/008/ae428e/ae428e02.htm Forests in Germany, 2007. www.wald.de Blattverlust >26% Blattverlust 11-25% -10% -30% -55% -75% 0% 30% 60% 85% Transparency Müller & Stierlin, 1990; Dobbertin, M et al. 2005 -0% -30% -60% -85% 1. Biological causes: insects/disease/livestock 2. Climatic conditions: drought, frost…… 3. Mechanical damage 4. Air pollution: emissions and effluents into the air, soil and water degrades the environment and causes defoliation