Waldbauliche Untersuchungen zur Überführung feuerländischer Lenga (Nothofagus pumilio)-Urwälder in Wirtschaftswald

Weihenstephan

2003

17 Lit. Ang.

Artikel aus einer Zeitschrift

200107049

The paper investigates concepts for the conversion of primeval forests of Lenga (Nothofagus pumilio) in Tierra del Fuego into managed forests and the silvicultural treatment of the subsequent stands. The results are based on the analysis of a series of stands in primeval forests as well as silvicultural experiments. It is shown that in the primeval forests two different types of natural dynamics can be found: a gap dynamic caused by the collapse of single old trees leading to uneven-aged stands in an equilibrium phase and large scale catastrophic wind breaks resulting in huge even-aged stands with an uniform structure. Although natural regeneration was abundant under both conditions a sufficient number of stems with good timber quality could be found only in even-aged stands. As threats by biotic and non-biotic factors (wood rot, wind) are increasing remarkably in stands older than 140 years, rotation length in managed forests should not exceed this age. As could be concluded from stem analyses, it is possible to reach target diameters of about 45 to 50 cm within that period if adequate silvicultural treatment is applied. Based on the different results, concepts for adequate conversion of primeval forests of different structure into managed stands are presented.