The fake greenery of Andalusia: when the forests look healthier than they really are
Climate change is hitting southern Spain hard. Recurrent droughts, rising temperatures, and the threat of fires paint a grim picture. However, satellite images reveal something surprising: Andalusia is greener today than it was three decades ago. Far from being good news, this phenomenon hides complex dynamics that show that more vegetation does not necessarily mean healthier or more resilient ecosystems.
### How the greening was measured
A team of researchers analyzed over 5,000 images captured between 1994 and 2021 by the Landsat 5 and 7 satellites. They calculated the NDVI, an index that measures the amount and vigor of vegetation. The study covered 2,358 plots of Andalusian Mediterranean forest, with special attention to holm oaks, cork oaks, pines, and chestnuts.
### Resilient species and changing cycles
The analysis showed that almost all species, except for the red eucalyptus, increased their green coverage. Holm oaks and cork oaks thrive in mild winters, while Aleppo and Maritime pines have extended their activity even in dry areas. However, other species, such as Scots pine or wild olive, have shortened their life cycle, showing that not all species are benefiting.
### Reasons behind the greenery
The greening is not solely due to natural adaptation. Reforestation policies, the progressive abandonment of agricultural lands, reduced livestock pressure favoring undergrowth, and a global factor: the increase in atmospheric CO₂, acting as a fertilizer. In some cases, human activity continues to limit species, as with cork oaks exploited for cork extraction.
The researchers warn that the increase in greenery does not imply that everything is improving. In many areas of southern and eastern Andalusia, vegetation barely grows, and aridity continues to spread. Furthermore, the increase in vegetation can disguise the loss of diversity, fragility to fires, and the weakening of less resistant species.
### Lessons for the future
This study provides crucial clues to design more effective reforestation policies: betting on species truly adapted to drought and aridity. The conclusion is clear: Andalusia may seem greener than before, but without proper management, that greenery is an illusion hiding ecosystems on the brink of collapse.
