PARENT SESSION
Monday, August 7, 5:00-6:30 pm
Poster Session 1 - Disturbance ecology
Exhibit Hall, Ballroom Level, Cook Convention Center

Effects of sand burial on the coastal dune grass Ammophila breviligulata.

Peek, Michael^*,1, Pelosi, Michael¹, ¹ Department of Biology, Wayne, NJ

ABSTRACT- Shoreline erosion represents a major problem for many coastal systems. American Beachgrass (Ammophila brevilugulata Fern.) acts as a natural stabilizer in this successional system. As a result, this dune vegetation is prone to severe disturbance and stress, most commonly burial by shifting sand. We monitored plant performance above and belowground throughout the summer of 2005 in response to an experimental addition of 10 cm/yr sand accretion rate, added in two increments. While we saw no effects of burial to sand, we did measure a uniform root length and weight distribution down to 70 cm, with an average weight of 0.39±0.027 mg/cm3 and an average length of 2.8±0.15 cm/cm3. Aboveground, the number of culms declined linearly from the start of the experiment, while plant height increased steadily until late August, then declined thereafter. The lack of a response to burial was not surprising as the start of the experiment was during the mid-summer, when soil moisture and temperatures were greatest and plant activity reduced. Surprisingly, however root biomass did not change through time or in the soil profile, suggesting the importance of biomass allocation to the root system and ultimately stabilizing shifting sand.

Key words: plant ecology, american beachgrass, coastal dunes