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Rivers are natural systems that adjust to variable water and sediment discharges. Channels with spatial variability in width that are managed to maintain constant widths over a period of time are able to transport the same water and sediment discharges by adjusting the bed slope. Methods developed to de ne equilibrium hydraulic geometry characteristics of alluvial channels are limited to steady state input variables.This dissertation examines how the channel slopes adjust in sequential reaches with different widths to achieve continuity of steady and unsteady water and sediment discharges....

The Fire and Fuels Extension (FFE) to the Forest Vegetation Simulator (FVS) simulates fuel dynamics and potential fire behavior over time, in the context of stand development and management. This chapter provides an introduction to the model by illustrating its purpose and chronicling some of the applications it has supported.

The Fire and Fuels Extension to the Forest Vegetation Simulator is a model that simulates fuel dynamics and potential fire behavior over time, in the context of stand development and management. Existing models are used to represent forest stand development (the Forest Vegetation Simulator, Wykoff and others 1982), fire behavior (Rothermel 1972, Van Wagner 1977, and Scott and Reinhardt 2001), and fire effects (Reinhardt and others 1997). These models are linked together with newly developed models of snag and fuel dynamics. Users can simulate fuel treatments including prescribed fire,...

The Fire and Fuels Extension (FFE) to the Forest Vegetation Simulator (FVS) simulates fuel dynamics and potential fire behavior over time, in the context of stand development and management. This chapter presents the model's options, provides annotated examples, describes the outputs, and describes how to use and apply the model.

The Fire and Fuels Extension (FFE) to the Forest Vegetation Simulator (FVS) simulates fuel dynamics and potential fire behavior over time, in the context of stand development and management. This report documents differences between geographic variants of the FFE. It is a companion document to the FFE "Model Description" and "User's Guide." People who use FFE variants can use this document to learn about the unique features of each geographic variant.

Foresters must consider many factors when selecting nursery stock types for their planting projects. Forest nurseries can now produce a vast array of stock types to meet any challenge in the field - these target seedlings can be defined for particular sites. It is important that foresters work with a nursery that is known from experience or reputation to provide a consistently good product at a reasonable price. Foresters and nurseries must foster open and effective communication to continually improve stock type quality. To facilitate communication between nurseries and foresters, a...

No thematic map is perfect. Some pixels or polygons are not accurately classified, no matter how well the map is crafted. Therefore, thematic maps need metadata that sufficiently characterize the nature and degree of these imperfections. To decision-makers, an accuracy assessment helps judge the risks of using imperfect geospatial data. To analysts, an accuracy assessment helps describe the reliability of the map for geospatial analyses and modeling, and the distribution of different types of "true" land cover within each mapped category. To producers of thematic maps, an accuracy assessmen...

A strategic plan is a tool for charting a path into the future. This Strategic Framework will help guide the USDA Forest Service Rocky Mountain Research Station over the next decade during inevitable socioeconomic and environmental change. It is the product of a dialog with our stakeholders and employees to examine the Station's capabilities, anticipate research issues, and describe our future role in providing scientific information to sustain the world's natural resources. This Strategic Framework describes how the Rocky Mountain Research Station will help accomplish the goals of the...

The rugged mountains of the Sierra Madre Occidental, in north-central Mexico, support a mosaic of diverse ecosystems. Of these, the high-elevation, temperate pine-oak forests are ecologically significant for their extensiveness and biodiversity. They cover nearly half the land area in the states of Durango and Chihuahua (42%), and comprise a similar percentage of the temperate coniferous forest in Mexico as a whole (45%; World Forest Institute 1994; SARH 1994). These forests are globally significant centers of vascular plant diversity, and of endemism in both plant and animal species (Bye...

Understanding the processes and patterns of gene flow and local adaptation requires a detailed knowledge of how landscape characteristics structure populations. This understanding is crucial, not only for improving ecological knowledge, but also for managing properly the genetic diversity of threatened and endangered populations. For nearly 80 years, population geneticists have investigated how physiognomy and other landscape features have influenced genetic variation within and between populations. They have relied on sampling populations that have been identified beforehand because most...