Rates of Mineral Element Leaching from Leaves of Nine Plant Species from a Southern Appalachian Forest Succession Subjected to Simulated Acid Rain

Abstract

HAINES, B., J. CHAPMAN AND C. MONK (Botany Department, University of Georgia, Athens, Georgia 30602). Rates of mineral element leaching from leaves on nine plant species from a southern Appalachian forest succession subjected to simulated acid rain. Bull. Torrey Botanical Club 112:258-264. 1985.-Rates of mineral element leaching from plants subjected to simulated acid rain were determined for plants from a forest succession. Early successional plants were the herbs Erechtites hieracifolia and Erigeron canadensis and the early successional shrub-tree was Robinia pseudo-acacia. Later successional species were Pinus strobus, Carya illinoensis, Liriodendron tulipifera, Quercus prinus, Acer rubrum and' Cornus florida. Simulated rain consisted of deionized water plus a salt and an acid component to produce pH values of 5.5, 4.5, 3.5 and 2.5. Solutions were applied through a raindrop simulator at 0.9 cm/hr for 10 periods of 1 hr each. Leachate from the leaves was collected and analyzed for NH4-N, NO3N, K, Ca, Mg, and P. Rates of leaching ranged from 0.006 to 11.3 mg of element/ 10 dm2/hr. There were highly significant differences in leaching rates among species but no significant differences among pH treatments for the elements analyzed. Highest leaching rates occurred in Erechtites and Erigeron. The absence of a pH effect on leaching rates is consistent with the absence of evidence of acid rain damage to the leaves of the plants tested.