Über die Anwendung der Dendrochronologie in der Moorforschung am Beispiel subfossiler Eichenstämme aus niedersächsischen Mooren

Abstract

Abstract. Die jahrringchronologische Auswertung subfossiler Eichenstämme aus drei niedersächsischen Mooren führt zum Nachweis eines im wesentlichen zwischen 350 und 150 v. Chr. an den verschiedenen Fundstellen gleichzeitig erfolgten Absterbens von Eichenbeständen. Es ergeben sich Hinweise auf eine Klimaschwankung in dieser Zeit. Die Bildungsgeschichte des Hochmoores bei Sieden läßt sich durch die Aufnahme von Baumfunden in situ in Verbindung mit den zugehörigen Moorprofilen rekonstruieren. Das norddeutsche Jahrringmaterial kann mit der Eisenzeitlichen Auwaldeichenchronologie synchronisiert werden und verlängert diese um gut 200 Jahre zum Älteren.

Subfossil European bog oaks: population dynamics and long-term growth depressions as indicators of changes in the Holocene hydro-regime and climate

“…First, there is the near disappearance of Irish bog oaks between c. 230 and 50 bc, something which should imply bogs becoming wetter. Second, there is a major dying-off phase in the German bog oak material (Delorme et al, 1981; and a germination phase in the German riverine oak material just at the same time Spurk et al, this issue). Spurk et al (this issue) state that such germination phases were generally triggered by wet conditions.…”

“…However, as the number of investigated sites increased the picture became diffuse. It became obvious that, besides regional climatic factors, other, often local, environmental factors were involved (Delorme et al, 1981). The same holds true for the depression phases in the tree-ring series.…”

Mid-Holocene pine woodland phases and mire development - significance of dendroecological data from subfossil trees from northwest Germany

“…6). This can be compared with subfossil oaks from mire sites in northwest Germany, in which germination and dying‐off phases often overlap by centuries (Delorme et al 1981; Leuschner et al 1985, 2002). The bog‐pine GDO phases are much shorter and the pine populations are more clearly delimited.…”

“…In summary, the subfossil bog‐pine woodlands document the transitional phase towards the onset of raised bog formation, as characterized by initial dry conditions that were followed by increasing wetness of the sites, whereas this development is at least partly the result of climate variations. A dry–wet sequence was also considered as a trigger for the formation of raised bog growth leading to the death and preservation of oak woodlands in northwest Germany (Delorme et al 1981; Leuschner 1992).…”