Remote sensing as a tool for monitoring potential effects of vegetation changes on threatened plants: A case study from southern European heterogenous landscapes [Dataset]

Landscape is in continuous transformation due to both anthropogenic and natural disturb-ances, which may have a large impact on the most vulnerable elements of biodiversity. Here we quantify vegetation changes over the past 35 years (1984–2018) and assess how these changes may impact threatened plants over a heterogeneous and highly diverse region in southern Europe. To achieve this goal, we first estimated the intensity and duration of gains and losses of vegetation changes based on NDVI and NBR indices from Landsat time series, using the LandTrendr algorithm on Google Earth Engine. Then, we tested if: 1) Natura 2000 (N2000) areas have experienced lower vegetation changes than non protected areas and thus are effective in protecting threatened plants, 2) vegetation changes around threatened plants differ across habitats and depending on the protection status of the area where they occur, and 3) the probability of occurrence of populations of threatened plant species increases on more stable places (i.e. lower vegetation changes). Results indicated an overall increase of vegetation, or greening trend, although N2000 areas experienced less gains and losses than non protected areas, which support their role in preserving habitats and slowing down human-induced land cover changes. Populations of threatened species tend to concentrate in places of lower changes irrespective of the spatial scale used for the analysis, the particular habitat they occur, and their inclusion within protected areas. Our approach demonstrates how monitoring vegetation changes by long-term remote sensing can help in the challenge of assessing both cryptic landscape transformation processes in protected areas, and potential external threats for priority plants in a comprehensive, fast and objective way. The conclusions drawn from this study are expected to serve as guidelines for a more effective conservation management in other environmentally heterogeneous regions.