Population differentiation in Spartina patens: gas-exchange responses to salinity

Abstract

Evaluated the effects of gradual vs sudden increase in salinity from 5 to ppt on leaf conductance and net carbon assimilation of two Spartina patens populations from USA Gulf Coast marshes. The Ferblanc population (which grows under high salinities in a brackish-saltmarsh zone) maintained greater net carbon assimilation than did the Clovelly population (which grows under low salinities of fresh-brackish zone) in 5 and 15 ppt salinity treatment. At 25 ppt salinity, net carbon assimilation was reduced by 10% for Ferblanc (not statistically significant), and by 22% for Clovelly population (significant). In addition, Ferblanc plants produced significantly greater leaf area than did the Clovelly population. -from Author