Growth of adult beech trees (Fagus sylvatica (L.) on a limestone stand (Gottingen/Sodderich) in dependance upon climate factors. III. Increment core analyses)

The annual radial increment from wood cores of 130 year old dominant beech trees (bhd > 60 cm) on a lime stone stand (district 2c of the forest directory Bovenden, Sodderich) was recorded and related to climatic factors (monthly means of precipitation, sun shine duration, temperature, relative air humidity, water pressure deficit, and global radiation) of the weather station of Gottingen and Kassel. Following results are interesting The mean radial increment curves of the crown discs, the top base discs and the wood cores in breast height run synchronously (Fig. 1). A strong correlation between the increment curves of the wood cores (at bhd) and the crown stems could be found (y(Rzw-Bk) = 0.847x(Rzw-St) - 0.235; r(2) = 0.7. Fig. 2). Radial growth is controlled by the climatic factors (KIND = weather index) of the previous and current year (Tab. 1. Fig. 3 to 8). The dominant influencing factor is precipitation of the months June to August. The radial increment is correlated negativly to the KINDs of sunshine duration, global radiation, temperature and water saturation deficit, the precipitation is positivly correlated. The respectivly additive combination of the single climatic indices (KINDall) is strongly correlated to the radial increment curve (KINDall(Rz) : r(2) = 0.71) within the short period 1970 to 1999 (Tab. 1).