Estructura y dinámica de bosques de Pilgerodendron uviferum afectados por incendios en la Cordillera de la Costa de la Isla Grande de Chiloé

Abstract

Currently, Pilgerodendron uviferum forests cover over 172,000 hectares of Chiloé Province. The traditional utilization of these forests caused the destruction and burnt of extensive areas of cypress. Therefore this species was classified by IUCN as vulnerable and included in Appendix I of CITES. This study aimed to analyze and characterize the dynamics of P. uviferum forests in the coastal range of Chiloé, specifically in four sites (one pristine and three disturbed) located near Lake Tepuhueico in the center-south of Chiloé Island. A floristic composition evaluation and quantitative, diametric and age structure analyses for each sector were conducted. Furthermore, the original stand structure of the burnt Pilgerodendron forests, existing before the fire, was reconstructed. The fire that occurred in the study area produced big changes in the habitat, exceeding the persistence threshold of P. uviferum. The disturbed zone was considerably damaged on its structure, showing substantial reductions of basal area (over 90%) and density (over 87%) for the species. This event allowed the establishment and dominance of young second-growth mixed stands of Nothofagus nitida, Drimys winteri and Tepualia stipularis which, in undisturbed sites, belong to a different succesional sequence. However, there are small pristine stands of P. uviferum that must be preserved because of their structural complexity and their importance as seed suppliers for disturbed neighboring areas.

Recuperar bosques no es solo plantar árboles: Lecciones aprendidas luego de 7 años restaurando bosques de Pilgerodendron Uviferum (D. Don) Florin en Chiloé

“…Es más, estos bosques turbosos son uno de los bosques templados costeros menos estudiados del sur de Sudamérica (Holz & Veblen, 2009), particularmente en su estado adulto inalterado (Bannister et al 2008). La presión antrópica sobre estos bosques para la extracción de madera ha causado la destrucción extensiva de estos "cipresales" a través de la quema para facilitar el acceso a los árboles (Lara et al 2014;Bannister et al 2008). La importancia de la madera de P. uviferum en el contexto histórico es demostrada por el establecimiento durante el siglo XIX de la industria forestal en la Isla de Chiloé y el Archipiélago de Las Guaitecas (Patagonia Norte).…”

“…Esta enorme superficie aumenta significativamente si se consideran todas las comunidades que presentan esta especie, y no solamente el tipo forestal (Donoso, 1981), ya que una gran extensión de éstos bosques no son oficialmente considerados dentro del tipo forestal (<10 árboles/ha y <2m altura). Sin embargo, los bosques turbosos dominados por P. uviferum representan un típico caso de ecosistema con baja resiliencia a incendios, en los cuales se queman gran parte de los árboles y semillas (Bannister, 2012), por lo cual luego de alteraciones extensivas estos bosques quemados no pueden retornar a bosques dominados por P. uviferum (Bannister et al 2008;Cruz & Lara, 1981).…”

The Importance of Microtopography and Nurse Canopy for Successful Restoration Planting of the Slow-Growing Conifer Pilgerodendron uviferum

“…This private biodiversity conservation area of 118,000 ha contains extensive disturbed areas of previously P. uviferum-dominated bog forests that were burnt mainly in an extensive fire of anthropogenic origin in 1943 [7,22]. Field sites were located in the disturbed forests around Lake Chaiguata.…”

“…Although drainage appears to be a relevant factor for the performance of P. uviferum seedlings in bogs, light may be the limiting factor in upland areas with better soil drainage, where the post-fire regrowth of broadleaved pioneer species, like Tepualia stipularis, Nothofagus nitida, D. winteri and Weinmannia trichosperma, inhibits the growth of P. uviferum seedlings, resulting in a gradual decline of the species [7,18]. In this context, removal of canopy to create gaps or semi-open areas for P. uviferum seedlings may be a useful option to establish the species in upland areas.…”

Anatomía comparada de la madera de Cupressaceae y su correspondencia con los estudios de filogenia

“…Presenta una distribución que abarca aproximadamente 1.600 km, convirtiéndola de esta manera en la conífera chilena con el mayor rango de distribución, desde la provincia de Valdivia (39º36' S) hasta la provincia de Magallanes (54º20' S) Lara et al 1999;Premoli et al 2001;Szejner 2007;Moreno 2007;Bannister et al 2008), siendo la especie de conífera más austral del mundo (Premoli et al 2001Grosfeld y Barthélémy 2001;Rovere et al 2002;Szejner 2007;Bannister et al 2008;Soto et al 2010). Abarca una amplia región de Chile, cubriendo un área total de 564.922 ha Premoli et al 2001), y en las partes adyacentes de Argentina se presenta en poblaciones aisladas.…”