Rewilding after clearcutting: a missing step for forestry sustainability

Investigador Responsable: Javier A. Simonetti
Coinvestigadores: Audrey A. Grez (Universidad de Chile), Patricio Pliscoff (Pontificia Universidad Católica de Chile) y Pablo Vergara (Universidad de Santiago de Chile)
Período:  2014- 2017
Financiamiento: Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT 1140657

Resumen/Abstract:

Forestry plantations are being increasingly demanded to provide services additional to the production of commodities, including maintaining native biodiversity, as agreed in the Strategic Plan for Biodiversity 2011–2020 of the Convention on Biological Diversity, that by 2020 “areas under agriculture, aquaculture and forestry are managed sustainably, ensuring conservation of biodiversity”. This claim contrast with commonly held opinions that forestry plantations are “biological deserts”, devoided of any wildlife. While the replacement of native vegetation by plantations does reduce species richness and abundance, this phenomenon occurs preferentially in plantations that are structurally simple, containing no or scarce understory vegetation. Experimental evidence supports the contention that mature Monterey pine plantations could support some native biodiversity, including endangered species, if they hold a well-developed understory. Interestingly, plantations with undergrowth are preferred by citizens, who are also willing to pay more for forestry products that come from biodiversity-friendly plantations, factors that suggests forestry might be sustainable.

Pine plantations, however, are harvested through clearcutting, a practice that renders the cleared areas unsuitable for forest-dwelling species.  A pending question is to determine the likelihood that newly established plantations will be colonized and used as habitats by the native fauna. Therefore, it is critical to unravel factors enhancing the chances of new plantations to be re-wilded by forest species. In this proposal, we will experimentally analyze whether the understory is a key factor enhancing the suitability of new plantations as habitat for forest fauna. At the local level, if the abundance of wildlife species in plantations after clear-cutting depends on understory development, wildlife species ought to be absent or occur at low frequencies in plantation stands where understory is scarce or experimentally removed. At the landscape level, after a clear-cut, the abundance and richness of ground-dwelling insects, medium-sized mammals as well as forest specialist birds should be reestablished faster in young pine plantations that are adjacent either to large native forest fragments or mature plantations which act as sources of recruitment and repopulation for plants and animals.

If understory and habitat sources determine the re-wilding of newly pine plantations, they could effectively contribute to wildlife conservation, fulfilling growing environmental standards world-wide.  Therefore, this project is aimed to provide foresters with simple and straight forward rules of habitat quality/connectivity for fauna which are based on the stand-scale management of understory and the spatial arrangement of stands relative to native remnants or adult pine stands.