David R. Butler – författare

The alpine treeline ecotone (ATE) is an area of transition high on mountains where closed canopy forests from lower elevations give way to the open alpine tundra and rocky expanses above. Alpine tundra is an island biome and its ecotone with forest is subject to change, and like oceanic islands, alpine tundra is subject to invasion - or the upward advance of treeline. The invasion of tundra by trees will have consequences for the tundra biome as invasion does for other island flora and fauna. To examine the invasibility of tundra we take a plant's-eye-view, wherein the local conditions become extremely important. Among these local conditions, we find geomorphology to be exceptionally important. We concentrate on aspects of microtopography (and microgeomorphology) and microclimate because these are the factors that matter: from the plant's-eye-view, but we pay attention to multiple scales. At coarse scales, snow avalanches and debris flows are widespread and create "disturbance treelines� whose elevation is well below those controlled by climate. At medium scales, turf-banked terraces create tread-and-riser topography that is a difficult landscape for a tree seedling to survive upon because of exposure to wind, dryness, and impenetrable surfaces. At fine scales, turf exfoliation of the fronts of turf-banked risers, and boulders, offer microsites where tree seedlings may find shelter and are able to gain a foothold in the alpine tundra; conversely, however, surfaces of needle-ice pans and frost heaving associated with miniature patterned ground production are associated with sites inimical to seedling establishment or survival. We explicitly consider how local scale processes propagate across scales into landscape patterns. The objective of this book is to examine the controls on change at alpine treeline. All the papers are focused on work done in Glacier National Park, Montana, USA. Although any one place is limiting, we are able to examine the alpine treeline here in some detail - and an advantage is that the treeline ecotone in Glacier National Park is quite variable in itself due to the underlying variability in geomorphology at multiple scales. This book will provide insights into an important ecological phenomenon with a distinctly geomorphic perspective. The editors collectively have over 100 years of experience in working in geomorphology, biogeography, and ecology. They also have each worked on research in Glacier National Park for several decades. The book will be a reference for a variety of professionals and students, both graduate and undergraduate, with interests in Physical Geography, Geomorphology, Ecology, and Environmental Science. Because of the importance of the alpine treeline ecotone for recreation and aesthetic interests in mountain environments, wildland and park managers will also use this book.Subject matter: geomorphology at alpine treelineExpertise of contributors: each editor brings over 25 years of experience in studies of ecotones and geomorphology, and collectively over 100 years of experience in Glacier National ParkChanging alpine treeline examines climate change

Animals as geomorphic agents have primarily been considered curiosities in the literature of geomorphology, whose spatial and quantitative influences have been seen as both limited and minor. Zoogeomorphology: Animals as Geomorphic Agents, which is wholly devoted to this topic, examines the distinct geomorphic influences of invertebrates, ectothermic vertebrates, birds and mammals, and demonstrates the importance of animals as landscape sculptors. Specific processes associated with the diversity of animal influences in geomorphology are examined, including burrowing and denning, nesting, lithophagy and geophagy, wallowing and trampling, food caching, excavating for food, and dam building by beavers. Particular emphasis is placed on terrestrial animals, although aquatic animals are also discussed where appropriate.

Animals as geomorphic agents have primarily been considered curiosities in the literature of geomorphology, whose spatial and quantitative influences have been seen as both limited and minor. Zoogeomorphology: Animals as Geomorphic Agents, which is wholly devoted to this topic, examines the distinct geomorphic influences of invertebrates, ectothermic vertebrates, birds and mammals, and demonstrates the importance of animals as landscape sculptors. Specific processes associated with the diversity of animal influences in geomorphology are examined, including burrowing and denning, nesting, lithophagy and geophagy, wallowing and trampling, food caching, excavating for food, and dam building by beavers. Particular emphasis is placed on terrestrial animals, although aquatic animals are also discussed where appropriate.

This book is devoted to the Anthropocene, the period of unprecedented human impacts on Earth’s environmental systems, and illustrates how Geographers envision the concept of the Anthropocene. This edited volume illustrates that geographers have a diverse perspective on what the Anthropocene is and represents. The chapters also show that geographers do not feel it necessary to identify only one starting point for the temporal onset of the Anthropocene. Several starting points are suggested, and some authors support the concept of a time-transgressive Anthropocene. Chapters in this book are organized into six sections, but many of them transcend easy categorization and could have fit into two or even three different sections. Geographers embrace the concept of the Anthropocene while defining it and studying it in a variety of ways that clearly show the breadth and diversity of the discipline.This book will be of great value to scholars, researchers, and students interested in geography, environmental humanities, environmental studies, and anthropology. The chapters in this book were originally published as a special issue of the journal Annals of the American Association of Geographers.

This book is devoted to the Anthropocene, the period of unprecedented human impacts on Earth’s environmental systems, and illustrates how Geographers envision the concept of the Anthropocene. This edited volume illustrates that geographers have a diverse perspective on what the Anthropocene is and represents. The chapters also show that geographers do not feel it necessary to identify only one starting point for the temporal onset of the Anthropocene. Several starting points are suggested, and some authors support the concept of a time-transgressive Anthropocene. Chapters in this book are organized into six sections, but many of them transcend easy categorization and could have fit into two or even three different sections. Geographers embrace the concept of the Anthropocene while defining it and studying it in a variety of ways that clearly show the breadth and diversity of the discipline.This book will be of great value to scholars, researchers, and students interested in geography, environmental humanities, environmental studies, and anthropology. The chapters in this book were originally published as a special issue of the journal Annals of the American Association of Geographers.

Dendrogeomorphology Beginnings and Futures: A Personal Reminiscence My early forays into dendrogeomorphology occurred long before I even knew what that word meant. I was working as a young geoscientist in the 1960s and early 1970s on a problem with slope movements and deformed vegetation. At the same time, unknown to me, Jouko Alestalo in Finland was doing something similar. Both of us had seen that trees which produced annual growth rings were reacting to g- morphic processes resulting in changes in their internal and external growth p- terns. Dendroclimatology was an already well established field, but the reactions of trees to other environmental processes were far less well understood in the 1960s. It was Alestalo (1971) who first used the term, dendrogeomorphology. In the early 1970s, I could see that active slope-movement processes were affecting the growth of trees in diverse ways at certain localities. I wanted to learn more about those processes and try to extract a long-term chronology of movement from the highly diverse ring patterns.