Ellen Wohl – författare

The ability of beavers to create an abundant habitat for a diverse array of plants and animals has been analyzed time and again. The disappearance of beavers across the northern hemisphere, and what this effects, has yet to be comprehensively studied. Saving the Dammed analyzes the beneficial role of beavers and their dams in the ecosystem of a river, focusing on one beaver meadow in Colorado. In her latest book, Ellen Wohl contextualizes North St. Vrain Creek by discussing the implications of the loss of beavers across much larger areas. Saving the Dammed raises awareness of rivers as ecosystems and the role beavers play in sustaining the ecosystem surrounding rivers by exploring the macrocosm of global river alteration, wetland loss, and the reduction in ecosystem services. The resulting reduction in ecosystem services span things such as flood control, habitat abundance and biodiversity, and nitrate reduction. Allowing readers to follow her as she crawls through seemingly impenetrable spaces with slow and arduous movements, Wohl provides a detailed narrative of beaver meadows.Saving the Dammed takes readers through twelve months at a beaver meadow in Colorado's Rocky Mountain National Park, exploring how beavers change river valleys and how the decline in beaver populations has altered river ecosystems. As Wohl analyzes and discusses the role beavers play in the ecosystem of a river, readers get to follow her through tight, seemingly impenetrable, crawl spaces as she uncovers the benefit of dams.

"A World of Rivers" explores the confluence of human and environmental change on ten of the great rivers of the world. Ranging from the Yellow River in China to Central Europe's Danube, the book journeys down the most important rivers in all corners of the globe. Wohl shows us how pollution, such as in the Ganges and in the Ob of Siberia, has affected biodiversity in the water. But rivers are also resilient, and Wohl stresses the importance of conservation and restoration to help reverse the effects of human carelessness and hubris. What these diverse rivers share is a critical role in shaping surrounding landscapes and biological communities, and Wohl's book ultimately makes a strong case for the need to steward positive change in the world's great rivers.

Far from being the serene, natural streams of yore, modern rivers have been diverted, dammed, dumped in, and dried up, all in efforts to harness their power for human needs. But these rivers have also undergone environmental change. The old adage says you can't step in the same river twice, and Ellen Wohl would agree - natural and synthetic change are so rapid on the world's great waterways that rivers are transforming and disappearing right before our eyes. "A World of Rivers" explores the confluence of human and environmental change on ten of the great rivers of the world. Ranging from the Murray-Darling in Australia and the Yellow River in China to Central Europe's Danube and the Mississippi, the book journeys down the most important rivers in all corners of the globe. Wohl shows us how pollution, such as in the Ganges and in the Ob of Siberia, has affected biodiversity in the water. But rivers are also resilient, and Wohl stresses the importance of conservation and restoration to help reverse the effects of human carelessness and hubris.What all these diverse rivers share is a critical role in shaping surrounding landscapes and biological communities, and Wohl's book ultimately makes a strong case for the need to steward positive change in the world's great rivers.

Sparsely settled mountain areas of the world, such as Colorado’s Front Range, give an impression of wild, untouched, and unchanging nature. Yet in many cases mountain rivers that appear to be pristine natural systems actually have been impaired as a result of human activities. In this timely and accessible book, Ellen Wohl documents two hundred years of land-use patterns on the Front Range and their wide-ranging effects on river ecosystems. If we hope to manage river resources effectively and preserve functioning river ecosystems, the author warns, we must recognize how beaver trapping, placer mining, timber harvesting, flow regulation, road and railroad construction, recreation, cattle grazing, and other human activities have impaired rivers--and continue to do so. The rivers of the Colorado Front Range are representative of mountain rivers throughout the world: land-use patterns affecting their form and function are little-recognized or -understood. This book fills an important gap with a clear and comprehensive explanation of how rivers are changed by human activity and includes a generous selection of striking historical and contemporary photographs, maps, and diagrams.

This important and accessible book surveys the history and present condition of river systems across the United States, showing how human activities have impoverished our rivers and impaired the connections between river worlds and other ecosystems.Ellen Wohl begins by introducing the basic physical, chemical, and biological processes operating in rivers. She then addresses changes in rivers resulting from settlement and expansion, describes the growth of federal involvement in managing rivers, and examines the recent efforts to rehabilitate and conserve river ecosystems. In each chapter she focuses on a specific regional case study and describes what happens to a particular river organism—a bird, North America’s largest salamander, the paddlefish, and the American alligator—when people interfere with natural processes.

An engaging and thought-provoking introduction to river scienceWhen we look at a river, either up close or while flying over a river valley, what are we really seeing? Following the Bend takes readers on a majestic journey by water to find answers, along the way shedding light on the key concepts of modern river science, from hydrology and water chemistry to stream and wetland ecology.In this accessible and uniquely personal book, Ellen Wohl explains how to “read” a river, blending the latest science with her own personal experiences as a geologist and naturalist who has worked on rivers for more than three decades. She charts how water travels through the hydrologic cycle around the globe and downstream to distribute energy, move sediment, and shape river channels, and how living organisms adapt to life in flowing water to create vibrant river ecosystems. Wohl looks at the role of disturbances such as floods and droughts and discusses how geologists interpret the sedimentary records of past river processes. She illustrates how river networks interact with Earth’s surface and considers issues for rivers in the future, such as progressive drying, river restoration, and advocating for the legal personhood of a river to maintain its distinctive spirit, identity, and integrity.Sharing a new understanding of how rivers function as both physical systems and ecosystems, Following the Bend enables us to observe rivers with fresh eyes and more fully appreciate the beauty, vibrancy, and complexity of our planet’s vital waterways.

Dead Wood explores the life and afterlife of three trees growing along a river: a spruce in the Colorado Rockies, a western red cedar in Washington, and a balsam poplar in Canada. Each tree is enmeshed in a biological community during its lifetime and continues to support other forms of life after death as the fallen tree enters a floodplain, a beach, or the open ocean.

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 107.Bedrock river channels are sites of primary erosion in the landscape, fixing the baselevel for all points upstream. This volume provides for the first time an integrated view of the characteristics and operation of this important, though hitherto neglected, class of channels. Examples are provided from several continents and cover a wide range of spatial scales from the large river basins (such as the Colorado River in the United States and the Indus River in Pakistan) down to reach scales and individual sites. Likewise the geologic timescales considered range from erosion and transportation during individual flows to accumulated effects over periods of tens of millions of years.

Published by the American Geophysical Union as part of the Water Resources Monograph Series, Volume 19.What are the forms and processes characteristic of mountain rivers and how do we know them? Mountain Rivers Revisited, an expanded and updated version of the earlier volume Mountain Rivers, answers these questions and more. Here is the only comprehensive synthesis of current knowledge about mountain rivers available. While continuing to focus on physical process and form in mountain rivers, the text also addresses the influences of tectonics, climate, and land use on rivers, as well as water chemistry, hyporheic exchange, and riparian and aquatic ecology. With its numerous illustrations and references, hydrologists, geomorphologists, civil and environmental engineers, ecologists, resource planners, and their students will find this book an essential resource.Ellen Wohl received her Ph.D. in geology in 1988 from the University of Arizona. Since then, she has worked primarily on mountain and bedrock rivers in diverse environments.

Rivers are the great shapers of terrestrial landscapes. Very few points on Earth above sea level do not lie within a drainage basin. Even points distant from the nearest channel are likely to be influenced by that channel. Tectonic uplift raises rock thousands of meters above sea level. Precipitation falling on the uplifted terrain concentrates into channels that carry sediment downward to the oceans and influence the steepness of adjacent hill slopes by governing the rate at which the landscape incises. Rivers migrate laterally across lowlands, creating a complex topography of terraces, floodplain wetlands and channels. Subtle differences in elevation, grain size, and soil moisture across this topography control the movement of ground water and the distribution of plants and animals.Rivers in the Landscape, Second Edition, emphasizes general principles and conceptual models, as well as concrete examples of each topic drawn from the extensive literature on river process and form. The book is suitable for use as a course text or a general reference on rivers. Aimed at advanced undergraduate students, graduate students, and professionals looking for a concise summary of physical aspects of rivers, Rivers in the Landscape is designed to: emphasize the connectivity between rivers and the greater landscape by explicitly considering the interactions between rivers and tectonics, climate, biota, and human activities;provide a concise summary of the current state of knowledge for physical process and form in rivers;reflect the diversity of river environments, from mountainous, headwater channels to large, lowland, floodplain rivers and from the arctic to the tropics;reflect the diverse methods that scientists use to characterize and understand river process and form, including remote sensing, field measurements, physical experiments, and numerical simulations;reflect the increasing emphasis on quantification in fluvial geomorphology and the study of Earth surfaces in general;provide both an introduction to the classic, foundational papers on each topic, and a guide to the latest, particularly insightful and integrative references.

Explores the effects of wildfires on land, water, vegetation, wildlife, and humansAcross the world, wildfires are increasing in frequency, extent, and severity, driven by changes in land use and climate. After the immediate hazards of fire and smoke have passed, landscapes and ecosystems can be left altered for decades.Landscapes on Fire: Impacts on Uplands, Rivers, and Communities presents an overview of wildfires and their after-effects on different parts of the natural, biological, and human landscape, bringing together perspectives from different disciplines.Volume highlights include: Causes, mechanics, and patterns of wildfireEffects of fire on uplands and river networksPredicting and mitigating fire-related hazardsProjected trends in wildfire patterns and effects due to climate changeCase studies from across the worldThe American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.