Impact of tephra deposition on growth in conifers: the year of the eruption

Abstract

Seven sites ranging from 15 to 135 km from Mount St. Helens were selected to study the impact of air-fall tephra on the growth of Abiesamabilis (Dougl.) Forbes, A. procera Rehd., Pseudotsugamenziesii (Mirb.) Franco, Tsugaheterophylla (Raf.) Sarg., and T. mertensiana (Bong.) Carr. As tephra depth increased, there was a corresponding increase in visible foliar damage and associated decreases in diameter and height growth. Reduction in diameter growth was greater than reduction in height growth. The reduction in diameter growth approached 50% in both trees and saplings of A. amabilis. Growth reduction in true firs was greater than in associated species. This difference was related to their greater capacity for interception and retention of air-fall tephra. Damage to trees, and resulting growth reductions, were due to tephra coverage of both the foliage and the soil. Coverage of the foliage resulted in foliar damage, foliage abscission and reduction of total tree foliar area, and increased fine root mortality. Tephra coverage of the soil had the potential to restrict oxygen diffusion into the soil. However, soil oxygen concentrations less than 10% were measured only once over a 2-year period.

Puyehue-Cordón Caulle eruption of 2011: tephra fall and initial forest responses in the Chilean Andes

“…Many studies have examined effects of tephra deposition on forests, including physical and chemical effects of tephra on foliage and effects of tephra burial on survival and growth rates (Seymour et al 1983, Antos and Zobel 1984, Hinckley et al 1984, Segura et al 1994, Ayris and Delmelle 2012. In our study tree survival/mortality was not simply related to total tephra fall depth, although the observed mortality patterns are consistent with the notion that thicker deposits are associated with higher forest mortality (Burt 1961, Ayris and Delmelle 2012, Swanson et al 2013.…”

“…In our study tree survival/mortality was not simply related to total tephra fall depth, although the observed mortality patterns are consistent with the notion that thicker deposits are associated with higher forest mortality (Burt 1961, Ayris and Delmelle 2012, Swanson et al 2013. At Mount St. Helens, growth decline depended on the depth of the fine tephra layer (Seymour et al 1984). The depth of the fine tephra at Caulle did not vary consistently among plots and our study period was brief, thus we cannot examine that variable with our data.…”

“…Tephra fall has been associated with several mechanisms for tree decline or death, including acid deposition, ash deposition effects on foliar energy and water balances, and alteration of soil gas, energy, water exchange or chemical properties (Seymour et al 1983, Hinckley et al 1984, Segura et al 1994, Ayris and Delmelle 2012. In this study, the larger mortality of evergreen N. dombeyi compared to deciduous N. pumilio, which was leafless at the time of the eruption, may provide indirect evidence that ash effects on foliage contributed to mortality.…”

A Decade of Recovery of Understory Vegetation Buried by Volcanic Tephra From Mount St. Helens

“…6) Woody plants survive deeper deposits than herbaceous plants, except (1) when stems are trapped beneath the tephra where it fell on snowpack, and (2) for some low-statured subshrubs with prostrate, slender woody stems (treated here in the herb layer). 7) Growth of woody plants usually declines but sometimes increases after tephra deposition (Hinckley et al 1984, Zobel and Antos 1985, Segura et al 1994. Growth increases of saplings in clearcuts (Zobel and Antos 1985) reversed with time (J.…”

Dendrochronological dating of volcanic events: a review

“…1 Fritts, 1976;Cook and Kairiukstis, 1990 , Yamaguchi, 1993;Schweingruber, 1996 Robock, 2000, Eggler, 1967Hinckley et al, 1984;Biondi et al, 2003, Eggler, 1967Biondi et al, 2003Eggler, 1967Hinckley et al, 1984;Biondi et al, 2003Yadav 1992 Larix cajanderii Yamaguchi 1983Yamaguchi , 1985 St. Helens Pseudotsuga menziesii Yamaguchi et al 1990 12 m 1977 Larix kaempferi Table . Volcanic events and their influence on trees in surrounding areas (modified from Yamaguchi, 1993 andSchweingruber, 1996 Swetnam, 1993 regime shift intervention analysis Rodionov, 2004 LaMarche and Hirschboeck, 1984;Scuderi, 1990;Briffa et al, 1998;Briffa, 2000;Robock, 2000;Salzer and Hughes, 2007;D Arrigo et al, 2009Scuderi, 1990Briffa et al, 1998 Salzer …”