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Springer Old Growth Forests - Chapter 16

Chapter 16 Old-Growth Temperate Rainforests of South America: Conservation, Plant–Animal Interactions, and Baseline Biogeochemical Processes Defining old-growth forests (Chap. 2 by Wirth et al., this volume) must consider both technical and cultural issues. For instance, the term ‘old-growth forest’ was entirely absent from the most recent survey | Chapter 16 Old-Growth Temperate Rainforests of South America Conservation Plant-Animal Interactions and Baseline Biogeochemical Processes Juan J. Armesto Cecilia Smith-Ramirez Martin R. Carmona Juan L. Celis-Diez Ivan A. Diaz Aurora Gaxiola Alvaro G. Gutierrez Mariela C. Nunez-Avila Cecilia A. Perez and Ricardo Rozzi 16.1 Introduction Defining old-growth forests Chap. 2 by Wirth et al. this volume must consider both technical and cultural issues. For instance the term old-growth forest was entirely absent from the most recent survey of Chilean vegetation conducted by the National Forest Service CONAF-CONAMA-BIRF 1999 where the forestry-related term adult synonym of tall 15 m height forest was used instead to indicate a harvestable unit of land. Moreover the deriding term over-mature is sometimes used to refer to old-growth stands with a predominance of large non-harvestable trees Chap. 2 by Wirth et al. this volume . This bias towards a tree-centred commercial view of forests suggests that culturally we remain unaware of the ecological differences among successional forest stages and of the specific attributes of old-growth forests. Greater public appreciation of the ecological social and economic values of old-growth forests will depend on our ability to communicate scientific understanding of these diminishing ecosystems. Based on current knowledge of temperate forests in southwestern South America e.g. Donoso 1993 Armesto et al. 1996a Veblen et al. 1996 Neira et al. 2002 we propose here a definition of old-growth forest that combines both structural and compositional based on species and functional groups properties of forest stands. The old-growth condition is usually restricted to ecosystems that have not been subjected to recurrent and massive human impact Chap. 2 by Wirth et al. this volume . Considering the entire range of human impacts from changes in the concentration of elements in the atmosphere to the extraction of individual trees it is however .