Treesearch

In many National Forests, much watershed restoration work involves road removal. Most National Forests have more roads than can be maintained with decreased budgets limiting the amount of roads that can be removed in any given year. Setting priorities for road closure based on the impacts and risks involved in closing, removing, or discontinuing maintenance has become a major challenge for forest managers. Stability and erosion risks are associated with unmaintained roads, and the same risks are associated with various removal strategies, such as culvert removal, surface ripping, outsloping...

The Columbia River Basin SUccession Model (CRBSUM) simulates broad-scale landscape changes as a consequence of various land management policies. CRBSUM is a spatially explicit, deterministic model with stochastic properties that simulates changes in vegetation cover types and structural stages on landscapes over long periods. CRBSUM was used to simulate coarse-scale landscape changes in the Interior Columbia River Basin as a result of four management scenarios called management futures. CRBSUM results have an inherent 1 to 5 percent variability because of the stochastic structure of the...

An ecological process model of vegetation dynamics mechanistically simulates longterm stand dynamics on coniferous landscapes of the Northern Rocky Mountains. This model is used to investigate and evaluate cumulative effects of various fire regimes, including prescribed burning and fire exclusion, on the vegetation and fuel complex of a simulation landscape composed of many stands. Detailed documentation of the model FIRE-BGC (a FIRE BioGeoChemical succession model) with complete discussion of all model parameters is followed with results of an application of the FIRE-BGC to a whitebark...

Presents highlights of Idaho's forest resources as of 1991. Describes the extent, condition, and location of the State's forests, focusing on timberland, includes statisticaltables providing data by area, ownership, forest type, species, volume, mortality, growth, and removals for timberland.

Riparian systems are a small but important resource in the southwestern USA and northern Mexico because of the diverse, dynamic, and complex biophysical habitats they provide. Wildfires have always produced the most significant impacts on riparian hydrology, geomorphology, and biology. Prescribed fires have not been used to any great extent in the Madrean Province for vegetation management in riparian systems. The unique geophysical characteristics of the Madrean Archipelago make it especially responsive to climatic events. Water yield, peakflow, and sediment yields after wildfires can be...

Fires can produce a wide range of changes in nutrient cycles of forest, shrub, and grassland ecosystems depending on fire severity, fire frequency, vegetation, and climate. These changes can be beneficial when fires increase the availability of plant nutrients, and deleterious when they volatilize, entrain ash in smoke columns, increase runoff of mineralized nutrients, or accelerate leaching from soil systems. This paper examines the effect of fires on nutrient cycling and flux pathways with special emphasis on Madrean-type ecosystems. Most of the best information on fire impacts on these...

Intense wildfires effectively remove vegetation, degrade watershed condition, and result in altered stream hydrographs and increased sediment input to streams. Case histories from five headwater streams in Arizona and New Mexico show effects of wildfire on aquatic habitats, fishes, and their food supply may be marked and long-lasting. Recent (1989-90) wildfires effectively extirpated two populations of brook trout (Salvelinus fontinalis), one of rainbow trout (Oncorhynchus mykiss) and the type locality population of the endangered Gila trout, (O. gilae). Aquatic macroinvertebrates densities...

This second conference on the Madrean Archipelago/Sky Island ecosystem brought together scientists, managers, and resource specialists from government, universities, and private organizations in the United States and Mexico to explore the effects of fire on Madrean Province ecosystem, and how fire can be incorporated in an ecosystem approach to both research and management.

The hypothesis that Neotropical migrant birds may be undergoing widespread declines due to land use activities on the breeding grounds has been examined primarily by synthesizing results from local studies. Growing concern for the cumulative influence of land use activities on ecological systems has heightened the need for large-scale studies to complement what has been observed at local scales. We investigated possible landscape effects on Neotropical migrant bird populations for the eastern United States by linking two large-scale inventories designed to monitor breeding-bird abundances...

The white-tailed deer is one of the most studied animals in North America, yet much of the available information has been derived in ecosystems different from the Black Hills. The Black Hills are unique in that the dominant species, ponderosa pine, has excellent regenerative abilities. This attribute, combined with timber management practices and fire suppression efforts in the last century, has allowed pine to expand at the expense of other plant communities. A critical first step in maintaining viable white-tailed deer populations in the Black Hills is identifying key winter ranges....