Ecological and socieconomic effects of an invasive canopy tree in the Gal?pagos Islands
- Authors
- Rivas Torres, Gonzalo Francisco
- Format
- DoctoralThesis
- Status
- publishedVersion
- Description
The presence of non-native invasive plants is speculated to from novel plant assemblages with unique abiotic characteristics that are rapidly replacing some of the main biomes worldwide. Particularly affecting unique island ecosystems. Despite the ecological and conservation implications of these ?novel ecosystems?, few studies have evaluated first, how novel are these communities when compared to extant native ecosystems and if in invasive species promote the formation of novel ecosystems; second, how removal of invasive plant species forming novel ecosystems affects recruitment and performance of both native invasive species; an third, assessed the socio-environmental dynamics of invasive timber species. I found that invasive forest plots had 42% lower native plant species richness and 17% lower native diversity than native forest plots. Invasive forests plots had 36% greater non-native plant richness and 37% higher non-native diversity. The invaded forests presented unique abiotic and structural characteristics including a more open and taller tree canopy, and more leaf litter than native forest. The presence of the invasive tree and the associated forest structural changes were the primary factors that best explained higher non-native plant diversity in the invaded forests. Additionally, I found that removal of the invasive dominant tree Cedrela odorata did not affect germination for any study species; but, positively affected establishment and growth of one native tree species-the highly threatened Scalesia pedunculata-and three invasive plants. The native tree S. pedunculata. Which once dominates the invaded site under study, was significantly benefited by C. odorata removal but was negatively affected by other factors such as attack from predators and competition for light with other fas-growing invasive species. These impacts were posteriorly valued and included in a hypothetical model that mapped the socio-ecological landscape providing a descriptive analysis of the broader social context surrounding C.odorata management. The resulting cost and benefits to stakeholder groups associated with C. odorata management are also evaluated and included in this conceptual model that can inform management of C. odorata by the Gal?pagos National Park (GNP)
- Publication Year
- 2015
- Language
- eng
- Topic
- BIOLOG?A
ECOLOG?A
CONSERVACI?N
MODELOS BAYESIANOS
SCALESIA PEDUNCULATA
PARQUE NACIONAL GAL?PAGOS
- Repository
- Repositorio SENESCYT
- Rights
- openAccess
- License