Bewertung der oekologischen Folgen des Waldsterbens anhand eines Szenarios.Dargestellt am Beispiel der Hamburger Forsten

Hamburg

1988

149 S.

55 Abb., 45 Tab., 20 Lit. Ang.

Bandaufführung

23418

During the past decade air pollution has increasingly affected the structure and development of forests. The development of this damage leads to open forest structures, especially in older stands, and finally can result in dieback of substantial forest areas in relative short time periods. As a result of this dramatical changes of stand structures the social-ecological functions of forests are significant decreasing. The conventional methods of forest management planning and forest damage survey give not the necessary informations for an objective immediately and long term estimation of the consequencesof the air pollution and new type of "forest decline" with regard to the funct ioning of the forests. Taking the forests of the City of Hamburg as an example,simulation calculations have been done based on a scenario for different pollu tion stresses for the time period from the year 1980 to 2030, using dynamic growth models for Scots pine, Norway spruce, Douglas fir, European beech and Pedunculate oak, the actual forest inventory data, the results of the forest damage survey and other investigations of forest decline in Hamburg. The results of the scenario should give informations about possible effects of the stability and functioning of the natural ecosystem and other functions of the forests in Hamburg. For orientation in 5-years-intervalls "time maps" have been calculated for each forest estate to demonstrate graphically the forest damage development. The program system calculated for a variant with light increasing pollutionstress a high percentage of havily damaged Scots pine and Norway spruce stands for the period from 1990 to 2000 and a high percentage of heavily damaged Euro pean beech stands for the period 2005 to 2010. The results of the scenario provide the possibility to start well-timed and system oriented silvicultural activities to limitate the endangered forest functions. The scenario indicates furthermore in time in which estates and stands silvicultural treatments are necessary.