Photosynthetic Characteristics of Marestail Using PAM Fluorometry

Abstract

Abstract. In this work, we used PAM fluorometry to examine photosynthetic characteristics of marestail (Hippuris vulgaris) across a water temperature gradient in three lakes. Three lakes were studied across a gradient in water temperature, with low water temperature conditions in Grass Lake and Arrow Bamboo Lake, high water temperature conditions in Five Colored Lake. Chlorophyll a concentrations of marestail differed strongly among the three lakes, with the highest value in Grass Lake. In three lakes, F v /F m of marestail declined as irradiance increased during the day, and recovered as light level decreased from noon until sunset. Photochemical quenching and non-photochemical quenching of marestail in Five Colored Lake were significantly higher than the other lakes. Our understanding of higher photosynthetic activity in Five Colored, as it relates to main environmental factors such as temperature.