Fires enhanced productivity in fire-adapted subtropical pinelands of the Florida Everglades

Some ecosystems require regular disturbances to maintain their biological and structural diversity. However, shifts in climate and changes in land management practices have altered global fire regimes, making it challenging to determine the most effective approach to maintain fire-dependent ecosystems. Measuring how ecosystems respond to disturbances can offer valuable insights into the effects of fire under contemporary conditions. In Everglades pinelands, we used satellite data to develop a machine learning model for the normalized difference vegetation index (NDVI), an effective proxy for primary productivity. Our findings showed that NDVI values ranged from 0.2 to 0.4 for Everglades pinelands, which were significantly influenced by fire history. Areas that experienced more frequent and more recent fires exhibited higher NDVI values compared to those that were less frequently burned. Conversely, pinelands that had not burned for an extended period (>15 years) showed signs of transitioning to less fire-dependent ecosystems. Following contemporary fires in Everglades pinelands, there was an initial reduction in NDVI of ∼6 %. However, on average, within 2 years, pinelands recovered to a higher post-fire NDVI (∼27 %) compared to their pre-fire levels. Our results suggest that more frequent fires enhance productivity and promote faster post-fire recovery in subtropical fire-dependent pinelands.