Unstable desert environments and vulnerability to plant invasions. A field and remote sensing assessment

Exotic plant invasions threaten biodiversity and ecosystem viability worldwide. We hypothesized that dynamic desert environments are unstable, therefore more vulnerable to plant invasions. To test this hypothesis we combined statistical and spatial analysis with field methods at multiple spatial and temporal scales to assess the potential distribution of the exotics Brassica tournefortii and Schismus arabicus in 'El Pinacate y Gran Desierto de Altar' Biosphere Reserve (PBR) in Sonora, Mexico. Combined models of high probability of invasion -influenced by human factors- and dynamic landscapes -detected in areas of past agricultural and current grazing activity- were tested with confirmed invasive locations. Results confirmed the hypothesis of the study and suggest that more dynamic landscapes are more prone to invasion by these two exotic plants in the PBR. These findings cannot, however, be conclusive due to the complex ecology of these invasives.