Forests in transition: a harvesting model for uneven-aged mixed species forests in Austria

• Published in: Forestry (London) Vol. 84; no. 5; pp. 517 - 526
• Main Authors: Thurnher, Christopher, Klopf, Mario, Hasenauer, Hubert
• Format: Journal Article
• Language: English
• Published: Oxford University Press 01-12-2011
• ISSN: 0015-752X; 1464-3626
• DOI: 10.1093/forestry/cpr021

Harvesting models are needed within simulation studies to assess 'business as usual' scenarios in future stand development. Such models require data from repeated observations addressing the removals as they are based on specific silvicultural management regimes. The purpose of this paper was to develop and apply a harvesting model for uneven-aged single-tree forest management based on data from the forest company 'Forstbetrieb Ligist, Souveräner Malteser Ritterorden' in Austria. This company has been known for its transition from even-aged to uneven-aged forest management since the 1930s. Our harvesting model comprises two logistic functions to simulate a single-tree selection process: (1) predicting the probability of harvesting and (2) removal. The set of equations are tested and implemented in the tree growth model MOSES (MOdelling Stand rESponse). MOSES is used as a diagnostic tool to assess different forest management regimes. In this study, we are specifically interested in (1) evaluating the model by comparing predicted and observed removals and (2) predicting future stand development considering the current management practices-the business as usual as it can be derived from the harvesting model. The results suggest that in combination with MOSES, our model correctly mimics the growth development over time since no systematic trends between predicted and observed diameter growth at breast height classes are apparent. Furthermore, it is evident that by applying the current plenter harvesting strategy, a constant stand basal area of ∼35 m2 ha-1 will be achieved.