Response of Ammophila breviligulata to acid rain and low soil pH

The effects of simulated acid rain and low soil pH on the growth of Ammophila breviligulata (Cape Strain), American beach grass, were studied in greenhouse experiments. Plants treated with acid rain were shorter, but shoot density, live shoot biomass, and rhizome biomass were not adversely affected by the acid rain treatments. Root biomass was greatest in the acid rain treatments. A manipulated soil pH of 4.0, typical of that found in field sites of dying beach grass, resulted in significantly reduced plant height, shoot density, shoot biomass, and rhizome biomass. Root biomass was greater in the low pH treatment and was six times greater than rhizome biomass in that treatment while the root to rhizome ratio was approximately 1∶1 in the control — likely a reflection of the plant's response to decreased nutrient availability in the low pH soil. Acid rain treatment of dune sand resulted in the leaching of Al, a potentially phytotoxic element.