Mount St. Helens Memoir

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Mount St. Helens Memoir

RogerRoger del Moral
Professor Emeritus of Biology

Dr. del Moral received his doctorate with C. H. Muller at the University of California, Santa Barbara, in 1968 and immediately joined the faculty at the University of Washington. Here he began a series of studies of vegetation patterns in forests and alpine sites of the Wenatchee Mountains, Alpine Lakes and Olympic Peninsula. In 1976-1977, he spent a year in Australia at the CSIRO in Queensland, where he learned about vegetation analysis, and at Melbourne University. Here, with David Ashton, he was the first to demonstrate that Eucalyptus inhibited native Australian shrubs in natural coastal heath. His pioneering work on plant competition in stable alpine habitats was interrupted by the 1980 eruption of Mount St. Helens. He was among the first ecologists to begin study of the recovery of this volcano, studies which have produced one of the longest continuous records of primary succession now extant and have resulted in over 70 papers. In 1984, he worked on reclamation of derelict sites in the U.K. (with A. D. Bradshaw), while in 1985 he was introduced to a wide variety of Japanese volcanoes including Fuji-san and Sakurajima. He has explored several volcanoes in the Russian Far East (Sergei Grishin), in Sicily (Emilia Poli Marchese) during his Sabbatical (2001), in Iceland (Hekla and Surtsey) with Borgthor Magnusson and in New Zealand. In 2007, he published Environmental disasters, natural recovery and human responses, a general book on restoring the landscape using the lessons gained from nature.

Research Interests
Dr. del Moral has studied and described vegetation structure in forests, prairies, wetlands and meadows throughout Washington. He has conducted large scale vegetation surveys, mapped the Alpine Lakes Wilderness and studied factors that control community structure in stable communities. Since 1980, his work has centered on primary succession and its relationship to restoration. Most of this work has explored the mechanisms of vegetation recovery on Mount St. Helens, but he has conducted research on several other volcanoes.  A series of papers have combined long-term plot records, focused field experiments and laboratory trials to explore mechanisms of primary succession. Several bits of "conventional wisdom" have been modified or shown to be overly simple. Stochastic processes are very important during early succession and landscape effects, more than any other factor, dictate the nature of early species assemblages. In contrast to prevailing theory, abiotic amelioration is much more important that biotic facilitation, physical safe-sites are initially more important than nurse plant effects, refugia contribute little to the development of their surroundings, and mycorrhizae play a very limited role on volcanic succession. His studies in Japan, the Russian Far East and Surtsey (Iceland) have shown that similar processes have controlled succession on volcanoes in these regions. With Lars Walker of UNLV, he completed a book on the current concepts of primary succession that summarizes the historical and developing concepts surrounding how landscapes are recolonized after devastating disturbances. Widely recognized as a major synthesis of the state of knowledge in primary succession, Primary Succession and Ecological Rehabilitation has won praise from ecologists and restorationists alike.

In 2007, he published a second book Ecological responses to natural disasters that was intended for a more general public. He and Lawrence Walker hope that this book stimulates a wider knowledge of ecological principles in the service of great quality of life. This book emerged, in part, from his strong interests in restoration ecology and built on his practical experience as a wetland consultant.

In 2014, after 45 years at the University of Washington, he retired from teaching, but he continues to explore succession and natural habitats.

Mount St. Helens Memoir
Professor del Moral created the longest continuous record of vegetation recovery on a new volcanic surface. His Mount St. Helens succession study described the first 32 years of change on this mountain and led to collaborations with scientists studying volcanoes in Iceland, Italy, Russia, Japan, the Philippines and elsewhere. He prepared a memoir providing a personal account of ecosystem recovery after volcanic eruptions.

In this memoir, he provides an account of major volcanic eruptions and their historical importance. These massive events include Thera, which devastated the Minoan civilization, Laki, whose 1783 eruption may have precipitated the French Revolution and 1883 Krakatau eruption. He describes how research in many habitats describing the mechanisms of the recovery on Mount St. Helens has expanded understanding of ecosystems recovery.

This memoir includes personal reflections of special times and special people. The work of many ecologists in multiple habitats is reviewed, but the focus is on the findings of his research team. The first section describes the range of volcanic impacts. The five chapters discuss tephra, blown-down forests, lahars, severely impacted sites and pyroclastic deposits. The second section explores successional mechanisms and advances in ecological theory. Chapters describe the importance of dispersal, how plants establish, patterns of development and mechanisms of vegetation maturation. A summary chapter explores how studies of Mount St. Helens have altered ecological theory. The final section describes the life histories and ecological attributes of most of the common plants found these successional habitats.

The memoir is well illustrated with images documenting the aftermath of the eruption, of the evolving landscapes and of many of the plant species found. High resolution images are available. Below are links to PDFs of each of the chapters.  The Vegetation Recovery of Mount St. Helens: a personal view of successional process.  

Preface & Introduction
Section I: Volcanic Events and Successional Responses
The Tephra Fall Zone
Blown-down and Seared Zone
The Vegetation Removal Zone
The Zone of Pyroclastic Deposits
Section II. Mechanisms of Succession
Blown-down and Seared Zone
Establishing in Barren Sites
The Development of Communities
The Maturation of Vegetation
How Mount St. Helens Changed our Understanding
Section III. Natural History of Typical Plants
Grasses & Lover Plants
Bibliography: Roger del Moral, related to Mount St. Helens
Links to Roger del Moral papers related to Mount St. Helens