Predicting and understanding wind-driven seed dispersal in fragmented landscapes with corridors

Background/Question/Methods

Widespread anthropogenic changes in landscape structure can alter dispersal and other movements of organisms, impacting populations, communities, and ecosystems. Key challenges in understanding wind-dispersed organisms are to extract the basic principles of wind dispersal in various types of fragmented environments, and to test them empirically in real fragmented landscapes. Working in a large-scale experiment, we used a novel combination of simulation models, season-long wind dynamics, and empirical seed releases to determine the mechanistic underpinnings of how landscape fragmentation and corridors alter wind dynamics, and consequently, wind-driven dispersal of plant species.

Results/Conclusions

We show that seed dispersal patterns can be predicted by modeling wind dynamics in fragmented landscapes and that corridors between open-habitat fragments facilitate dispersal of seeds. Specifically, open-habitat conservation corridors enhance dispersal by funneling and “bellowing” winds, intensifying seed uplift above the canopy and increasing dispersal distances especially when aligned with predominant winds. Corridors promote long distance wind-dispersal regardless of their orientation, but are maximally effective when aligned with the predominant wind direction during the dispersal season. Combining models, long-term data, and experiments provides a robust test of the impacts of habitat fragmentation and conservation corridors on wind dynamics and dispersal at large scales.