William W. Doe

Landscape erosion and evolution modeling

Preface. Acknowledgements. Contributors. 1. Introduction to Soil Erosion and Landscape Evolution Modeling. 2. Erosion Problems on U.S. Army Training Lands. 3. Effects of Freeze-Thaw Cycling on Soil Erosion. 4. Determination of Slope Displacement Mechanisms and Causes. 5. Using Cosmogenic Nuclide Measurements in Sediments to Understand Background Rates of Erosion and Sediment Transport. 6. Erosion Modelling. 7. The Water Erosion Prediction Project (WEPP) Model. 8. A Simulation Model for Erosion and Sediment Yield at the Hillslope Scale. 9. Waterbots. 10. Two-Dimensional Watershed-Scale Erosion Modeling with CASC2D. 11. Multiscale Soil Erosion Simulations for Land Use Management. 12. The Channel-Hillslope Integrated Landscape Development Model (CHILD). 13. Simulation of Streambank Erosion Processes with a Two-Dimensional Numerical Model. 14. Spatial Analysis of Erosion Conservation Measures with LISEM. 15. Numerical Simulation of Sediment Yield, Storage, and Channel Bed Adjustments. 16. The Limits of Erosion Modeling. 17. Envisioning a Future Framework for Managing Land and Water Resources. Index.

Introduction to Soil Erosion and Landscape Evolution Modeling

Landscapes evolve under the influence of a complex suite of natural processes, many of which may be either directly or indirectly influenced by land use. Soil erosion is a natural landscape process of critical concern to many land management agencies. As a geomorphic process, soil erosion can be generally defined as the detachment and transport of in-situ soil particles by three natural agents — water (in liquid or ice form), wind, and gravity (down slope movement). The consequences of soil erosion are both the removal and loss of soil particles from one location and their subsequent deposition in another location, either on the land surface or in an adjoining watercourse. A single soil particle may undergo multiple cycles of removal and deposition over time spans ranging from a single-event (e.g., hours) to geologic time (e.g., decades or centuries). Naturally occurring soil erosion processes (detachment, transport, deposition) can be accelerated by anthropogenic activities.

America’s Military Footprint: Landscapes and Built Environments within the Continental U.S.

Megaprojects are huge in scale and cost and can have significant economic, social and environmental impacts, both positive and negative, on the surrounding landscape and communities. The U.S. military landscape is by far the largest, most expensive, and most enduring of the megaprojects addressed in this book. Indeed, America’s current military footprint has been evolving for more than 230 years and today includes more than 30 million acres within the nation’s states (Doe, 2008). Military lands comprise a unique component of the federal land management system in the U.S. These lands reflect the country’s development and history, beginning as coastal defenses and outposts on the frontier, to becoming major military installations that are self-contained municipalities. Controlled by the four Armed Services (Army, Navy, Air Force, and Marine Corps), military lands include all land within the “fenceline” of a military installation, including two primary areas: (1) the cantonment – the built up component or “city” that houses and supports military personnel and their families, and (2) the range and training complex – consisting of live-fire ranges, bombing ranges and maneuver areas for training and testing of personnel, units and equipment. Irrespective of base realignments and closings, the military landscape within the U.S. is destined to continue as the federal government’s largest, most expensive, and most enduring megaproject.