Effects of Sand Accretion on photosynthesis, Leaf-Water Potential and Morphology of Two Dune Grasses

Field studies were conducted to determine the effects of burial in sand on net CO 2 uptake, water potential and leaf morphology of two grasses, the C 3 , Ammophila breviligulata and the C 4 , Calamovilfa longifolia. Buried plants of both species exhibited higher net photosynthetic rates than controls. However, the increase in net CO 2 uptake was much greater in A. breviligulata than in C. longifolia. At the same burial depth, C. longifolia usually maintained a greater net photosynthetic rate than A. breviligulata. Sand accretion did not influence the water potential of leaves but resulted in a slight increase (not significant) in leaf thickness of A. breviligulata but a significant increase in leaf thickness of C. longifolia (...)