PARENT SESSION
Contributed Oral Session 76: Estuary and Coastal Management
Wednesday, August 10, 8:00 AM - 11:30 AM, Meeting Room 514 A, Level 5, Palais des congrès de Montréal

The effect of multiple stressors on salt marsh end-of-season biomass.

Visser, Jenneke^*,1, Sasser, Charles¹, ¹ Louisiana State University, Baton Rouge, Louisiana

ABSTRACT- Understanding the factors that control plant growth is an important component of ecosystem ecology. It is becoming more apparent that commonly used statistical methods are not the best methods for estimating limiting relationships or stressor effects. A major challenge of estimating the effects associated with a measured subset of limiting factors is to account for the effects of unmeasured factors in an ecologically realistic matter. We used quantile regression to elucidate multiple stressor effects on end-of season biomass data from two salt marsh sites in coastal Louisiana collected for 18 years. Stressor effects estimated based on available data were flooding, salinity, temperature, grazing by muskrat, precipitation deficit, nitrogen and phosphorus availability and solar radiation. We demonstrated that solar radiation was the most frequent limiting factor at our study sites, followed by nitrogen limitation. We show that salinity was rarely the limiting factor for Spartina alterniflora biomass production at our sites.

Key words: Spartina alterniflora, quantile regression, multiple stressor