Why compare hemispheres: a case of salt marsh response to sea-level change

CHRISTIAN, R.; BLUM, L.; LEORRI, E.; PRATOLONGO, P.

San Diego

Conferencia; CERF 2013-Toward resilient coasts and estuaries: Science for sutainable solutions; 2013

Coastal and Estuarine Research federation

Climate, hydrogeomorphology and biota interact to determine the ability of coastal marshes to maintain themselves under changing sea levels. While models broadly predict the interactions, their applicability is limited to a range conditions less than the range of marshes and environmental drivers. We evaluated differences between eastern North and South American marshes in controlling factors of marsh response to sea level change. Eastern South American climate demonstrates a strong bifurcation compared to the latitudinal gradients in eastern North America. Dry, cold conditions in Patagonia are not represented in North America. Significant differences also exist in Holocene history and past and present sea-level change patterns. Marsh plant and animal communities show hemispheric species differences, especially in the high marsh and in colder climates. We consider that South American marshes have the potential to expand and qualitatively alter our understanding of marsh response to sea-level change. Unfortunately, they lack much of the quantitative information available for North American marshes to populate current models.