RAPID: Impact of Hurricanes Eta and Iota on Lake Yojoa

Global change is rapidly altering many tropical ecosystems with little understanding of how those changes impact the characteristics of those ecosystems and the services they provide. An important force in this change is the increase in hurricane frequency and intensity. In November of 2020, two hurricanes (Eta and Iota) moved from the Caribbean basin to across the Honduran mainland in quick succession.

Each hurricane generated massive rainfall as it downgraded to a tropical storm and flooded the Sula Valley in north-central Honduras. Lake Yojoa, located in north central Honduras, the only natural lake in Honduras, has been home to human populations for > 4000-years, and as such, carries an important sense of place for many Hondurans. Addressing challenges of global freshwater sustainability requires an intimate understanding of ecosystems from across the globe.

This RAPID will assess how the increasingly frequent massive rainfall events caused by the recent hurricanes impacts tropical aquatic ecosystems by altering the physical dynamics and water chemistry of tropical lakes and the watersheds that sustain them.

This RAPID represents a unique opportunity to close knowledge gaps at the intersection of three deficits in the current understanding of freshwater ecosystems. First, tropical lakes that experience stratification and mixus are understudied compared to their temperate counterparts. Second, lake ecosystems are rarely considered in the context of the watersheds within which they reside.

Third, in order to fully understand the impact of global change on aquatic ecosystems, time-series data that can distinguish between intra-annual and inter-annual variability are necessary. This project addresses the impact of two large hurricanes on a monomictic tropical lake in Central America (Lake Yojoa) and its watershed. In doing so, it provides the opportunity to a) advance our understanding of the biogeochemistry of tropical monomictic lakes, b) identify key linkages between watershed-derived-allochthonous nutrient delivery and internal lake biogeochemical dynamics and c) identify the impact of hurricanes on tropical watersheds and the lakes they contain.

By rapidly deploying a lake and watershed sampling design and comparing contemporary dynamics to analyses conducted previous to the hurricanes, this RAPID will advance our understanding of these important knowledge gaps within the context of the current understanding of tropical freshwater ecosystems.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.