Espèces végétales non-natives sur une île subantarctique chilienne : étude des perceptions des parties prenantes, modélisation des dynamiques de niches des espèces et cartographie des points chauds

The growth of human activities over the last century has contributed to the dispersal and establishment of non-native plant species around the world. These species are important drivers of environmental change since they have the capacity to modify native plant communities, especially through compet...

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Bibliographic Details
Main Author: Crête, Gaëlle
Other Authors: Herrmann, Thora Martina, Schüttler, Elke
Format: Thesis
Language:French
Published: 2020
Subjects:
geo
Online Access:http://hdl.handle.net/1866/23758
Description
Summary:The growth of human activities over the last century has contributed to the dispersal and establishment of non-native plant species around the world. These species are important drivers of environmental change since they have the capacity to modify native plant communities, especially through competition. Since human are the main drivers of introduction, establishment and spread of non-native species and since management strategies need to take into account public attitudes to be successful, it is necessary to understand the perceptions and choices regarding their use and management. The present study aimed to: i) understand the perceptions of different stakeholders towards the different non-native plant species of Navarino Island, a buffer zone of the Cape Horn Biosphere Reserve (CHBR) in the Chilean sub-Antarctic region and ii) identify niche dynamics and high potential establishment areas (i.e. hotspots) of four of these species, which together will serve as multidisciplinary tools for the CHBR management. To address the first objective, seven stakeholder groups were identified (i.e residents, elder residents, conservationists, marine members, tourists, Yaghan community members, public service employees), within which 21 semi-directed interviews were conducted. To address the second objective, global and regional occurrences of four of the most abundant species, i.e. Bellis perennis, Cerastium fontanum, Taraxacum officinale and Trifolium repens and associated climatic data were used to develop species distribution models using the maximum entropy method (MaxENT). Regarding the first objective, results of this study revealed shortcomings in the non-native concept understanding among stakeholders in a local context. On the other hand, the analyzes revealed many positive values associated with non-native plant species in Navarino, notably the aesthetic value. Nevertheless, this study showed that most stakeholders were indifferent to the management of non-native herbaceous plant species. Regarding the second ...