Treesearch

Computer simulation models can be usefully applied to many different outdoor recreation situations. Model outputs can also be used for a wide variety of planning and management purposes. The intent of this chapter is to use a collection of 12 case studies to illustrate how simulation models have been used in a wide range of recreation situations and for diverse planning and management applications.

This report is volume 2 of a two-volume ecological assessment of grassland ecosystems in the Southwestern United States. Broad-scale assessments are syntheses of current scientific knowledge, including a description of uncertainties and assumptions, to provide a characterization and comprehensive description of ecological, social, and economic components within an assessment area. Volume 1 of this assessment focused on the ecology, types, conditions, and management practices of Southwestern grasslands. Volume 2 (this volume) describes wildlife and fish species, their habitat requirements,...

This fact sheet describes the sources of sediment in upland forest watersheds in the context of fuel management activities. It presents the dominant forest soil erosion processes, and the principles behind the new sediment delivery interface developed to aid in erosion analysis of fuel management projects.Other publications in this series

The BehavePlus fire modeling system is a program for personal computers that is a collection of mathematical models that describe fire and the fire environment. It is a flexible system that produces tables, graphs, and simple diagrams. It can be used for a multitude of fire management applications including projecting the behavior of an ongoing fire, planning prescribed fire, and training. BehavePlus is the successor to the BEHAVE fire behavior prediction and fuel modeling system. Primary modeling capabilities include surface fire spread and intensity, safety zone size, size of point...

Determining the economic effectiveness of wildfire suppression activities is complicated by difficulties in identifying the area that would have burned and the associated resource value changes had suppression resources not been employed. We developed a case study using break-even analysis for two large wildfires from the 2003 fire season in western Montana -- the Black Mountain and Crazy Horse Fires. We used GIS to identify the location and taxable value of private residences within perimeters expanding in a likely direction of fire spread for both fires. We identified the size of an...

Snags (standing dead trees) are important components of forests that contribute to ecological processes and provide habitat for many life forms. We monitored dynamics of snag populations on 1-ha plots in southwestern mixed-conifer (n = 53 plots) and ponderosa pine (Pinus ponderosa, n = 60 plots) forests in north-central Arizona from 1997 to 2002. Of 2,240 snags marked in 1997, at least 76% remained standing in 2002, 17% had fallen and were relocated as logs, 0.5% were cut down, and the remainder (6%) were unaccounted for. Snag density increased significantly in mixed-conifer forest but not...

As the case studies in Chapter 4 illustrate, simulation modeling can be a valuable tool for recreation planning and management. Although simulation modeling is already well developed for business applications, its adaptation to recreation management is less developed. Relatively few resources have been devoted to realizing its potential. Further progress is needed in refining the models, and their inputs and outputs. Equally important is work to assess the validity of models as well as to understand the precision of model estimates and the appropriateness of using model outputs for various...

We studied Mexican spotted owl (Strix occidentalis lucida) diets and the relative abundance and habitat associations of major prey species in a ponderosa pine (Pinus ponderosa)–Gambel oak (Quercus gambelii) forest in northcentral Arizona, USA, from 1990 to 1993. The owl’s diet was comprised of 94% mammals by biomass and consisted of primarily the deer mouse (Peromyscus maniculatus), brush mouse (P. boylii), Mexican woodrat (Neotoma mexicana), and Mexican vole (Microtus mexicanus). Spotted owl prey in our study area were smaller on average than prey in other locations, and the total biomass...

We compared patch structure, fire-scar formation, and seedling regeneration in patches of low, moderate, and high burn severity following the large (~34 000 ha) Jasper fire of 2000 that occurred in ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) forests of the Black Hills of South Dakota, USA. This fire created a patchy mosaic of effects, where 25% of the landscape burned as low, 48% as moderate, and 27% as high severity. Dead cambium on a significant portion of tree circumference in a tree with live cambium and a vigorous crown was taken as evidence of incipient fire-scar...

Fledging success is often assumed to be a reliable index of reproductive success (i.e., fitness) in the ornithological literature. We examined the validity of this assumption in a large population of Northern Goshawks (Accipiter gentilis) on the Kaibab Plateau, Arizona, at both the population and individual levels. We used mark-recapture data from 558 fledglings produced at 494 nests over a 10-yr period to assess the hypothesis that the number of fledglings returning to breed from an annual fledgling cohort is positively correlated with the size of the cohort. Natal philopatry was low and...