Acid rain and soils of the Adirondacks. II. Evaluation of calcium and aluminum as causes of red spruce decline at Whiteface Mountain, New York
1994
Johnson, A.H. (University of Pennsylvania, Philadelphia, PA.) | Schwartzman, T.N. | Battles, J.J. | Miller, R. | Miller, E.K. | Friedland, A.J. | Vann, D.R.
Several recent publications suggest that acid deposition produces high anion concentrations in the soil solution of high-elevation forests, causing Al-induced Ca deficiency in red spruce (Picea rubens Sarg.) root tips. Some authors suggest that this results in decreased growth below and above ground, decline, and ultimately in death. Accordingly, we examined soil solution Al and Ca, soil and foliar chemistry, and their relationship to red spruce decline on Whiteface Mountain, New York, where severe red spruce mortality occurred between the mid-1960s and late 1980s. Spruce mortality and crown condition are strongly related to elevation, but there is no evidence that the occurrence or degree of spruce decline is related to exchangeable Al, Mg, Ca, or their ratios in mineral or organic horizons. Foliar Ca and Mg concentrations that we measured were in the range judged to be sufficient based on field fertilization studies. Soil solution ratios of Ca:Al in mineral and organic horizons were above the threshold (1:1 molar ratio) proposed as detrimental to Ca uptake in all samples collected during three of four growing seasons, and soil-solution Al concentrations were well below levels thought to inhibit spruce root growth. If Al toxicity is a factor in red spruce decline on this mountain, it is acting in a way that is not detectable using soil and foliar analyses
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