Abstract Detail

From High Islands to the Ocean Floor: Pacific Island Plants at the Extreme

Life on the Edge: Sea Level Rise Effects on Coastal Dune Plants.

Coastal dune ecosystems foster biodiversity, stabilize shorelines, and provide cultural ecosystem services. The persistence and stability of these critical ecosystems are threatened by the simultaneous effects of biological invasions and climate change, particularly on islands where floras are disproportionately endemic. Using experimental and trait-based approaches, we investigated the effects of simulated sea level rise via salinity treatments on native and invasive coastal dune plants in Hawaii. Salinity suppressed seedling growth across all species, although the magnitude of growth reduction varied dramatically. Osmotic stress associated with salinity was evidenced by significant reductions in stomatal conductance across all species, and the rate and degree of recovery in conductance rates following the salinity period contributed to plant growth, shedding light on the mechanisms underlying species variation in salinity tolerance. Invasive species were, on average, more susceptible to salinity than native species, indicating potential resilience of these dune communities to plant invasion under sea level rise. Field trait data corroborate these findings, illustrating functional overlap between native and invasive plants in leaf economic strategies consistent with biotic resistance to competitive displacement by invasive plants. These results highlight the urgency of climate change effects on coastal communities and emphasize the need to develop management plans to mitigate sea level rise threats to coastal dune plants in order to conserve these critical ecosystems.

1 - University Of Hawaii, School Of Life Sciences, 2538 McCarthy Mall , Edmondson Hall, Room 216, Honolulu, HI, 96822, United States

Keywords:
Island Ecology
Phenotypic plasticity
invasive species
climate change
Salinity Tolerance.

Presentation Type: Symposium Presentation
Number: S6004
Abstract ID:262
Candidate for Awards:None