Forest Understory Buried by Volcanic Tephra: Inertia, Resilience, and the Pattern of Community Redevelopment
We studied the effects of tephra deposits on understory plants in old-growth conifer forests NE of Mount St. Helens, including initial damage and the subsequent 30 years of vegetation redevelopment. The amount of damage to plants increased and the degree of recovery declined as plant size decreased, as tephra depth increased, and where tephra fell on snow. Major herb species were affected strongly by tephra depth, whereas damage to shrubs resulted primarily where tephra fell on snow. Cover in 2010 remained significantly correlated with the amount of damage, evidence of the long-term effects of tephra disturbance.
KeywordsBryophytes Growth form Herbs Long-term studies Resilience Shrubs Snow–tephra interaction Succession Tephra Tree seedlings
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