Deforestation-induced immediate and delayed shifts in moisture recycling: source and sink dynamics across the Amazon

Moisture recycling is a fundamental process within the Amazon, sustaining regional precipitation, maintaining ecosystem stability, and providing an important ecosystem service locally and globally. However, deforestation disrupts this process, altering moisture source and sink dynamics of areas in the Amazon and impacting the overall moisture recycling function. This study examined the spatial and temporal variability of moisture recycling by assessing the responses of moisture sources and sinks to deforestation across different time lags, focusing on the Amazon's contribution to and dependency on its moisture recycling regime. We used the UTrack moisture tracking model and high-resolution deforestation data from MapBiomas to quantify changes in dependency and contribution of the Amazon over a 22-year period (2000–2021). Our findings revealed high heterogeneity in moisture recycling patterns across the Amazon. We also found that deforestation affects both immediate and delayed moisture recycling responses, with mid- and long-term responses (13–48 months and 49–72 months) more pronounced than immediate responses (1-12 months). Deforestation is associated with a decreasing evaporation contribution of the Amazon to its moisture recycling regime as moisture sources and an increasing dependency for precipitation as moisture sinks. These results underscore the persistent and delayed effects of deforestation on the hydrological cycle of this important biome.