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A key product of both Forest Inventory and Analysis (FIA) of the USDA Forest Service and the Natural Resources Inventory (NRI) of the Natural Resources Conservation Service is a scientific data base that should be defensible in court. Multiple imputation procedures (MIPs) have been proposed both for missing value estimation and prediction of non-remeasured cells in annualized forest inventories such as the Southern Annual Forest Inventory System (SAFIS). MIPs generate clean-looking data bases that are easily used but hide a serious weakness: under different assumptions made by reasonable...

One of the great and largely unmet challenges associated with ecosystem management is treating people as a rightful part of ecosystems. In many ecosystem models, despite occasional rhetoric to the contrary, there is still a tendency to treat people as autonomous individual agents outside the ecosystem, at best a source of values to be incorporated into decisions, at worst agents of catastrophic disturbances of an otherwise smoothly running system. Many scholars have made suggestions for bringing social concepts and variables into ecosystem models and assessments (Driver et al. 1996; Force...

The most prevalent approach to understanding recreation experiences in resource management has been a motivational research program that views satisfaction as an appropriate indicator of experience quality. This research explores a different approach to studying the quality of recreation experiences. Rather than viewing recreation experiences as a linear sequence of events beginning with expectations and ending with outcomes that are then cognitively compared to determine experience quality, this alternative approach views recreation as an emergent experience motivated by the not very...

Tourism, especially rural tourism, epitomizes the problematic elements of sustainability. On the one hand, as a service industry trading on the uniqueness of a place and region, tourism is seen as more environmentally benign than industrial production, manufacturing, extractive industries, and even agriculture. When traditional resource dependent industries decline (whether due to depletion of resources, emergence of more competitive alternatives, or promulgation of environmental regulations), local communities, environmental organizations, and politicians often turn to tourism as a way to...

Vegetation at the Glacier Lakes Ecosystem Experiment Site, a 600 ha research site at 3200 to 3500 m elevation in the Snowy Range of southeastern Wyoming, was categorized and described from an intensive sampling of species abundances. A total of 304 vascular plant taxa were identified through collection and herbarium documentation. Plots with tree species were separated from those without tree species for ordination and classification analyses. Detrended correspondence analysis was used to order plots along major axes of composition variation, which are inferred moisture and topographic...

This study examined the variations in the chemical parameters of soils of seven forests located along a historical deposition gradient spanning 8.5° longitude from southern Illinois to central West Virginia. Four to six mature control plots were sampled on two of the sites, and two experimentally thinned and two control plots were sampled on the remaining five sites. Most soil properties varied significantly both among experimental forests and between control and thinned plots. Soil pH, Al, PO 4 and inorganic N were correlated with longitude, whereas differences in Ca, Mg and Ca:A1 ratio...

Soils were mapped on the 22,533 ha Desert Experimental Range, Utah, to determine the kind, extent, and distribution of major soils and soil groups, the type of vegetation associated with each soil group, and the correlation between herbage production and soil groups. The results indicated that Desert Experimental Range soils are primarily Haplocalcids, Torriothents, and Torrifluvents. They occur within the Temperate Desert and Temperate Steppe climatic types. Annual herbage production averages 250 kg per ha per year. High production years yield twice the average, often with many annual...

Many forest roads are being closed as a step in watershed restoration. Ripping roads with subsoilers or rock rippers is a common practice to increase the infiltration capacity of roads prior to closure. When considering the effectiveness of ripping for reducing runoff and erosion and the potential reduction in slope stability by saturating road fills, it is important to know how ripping changes the infiltration capacity of forest roads. Hydrographs from simulated rainfall on 1-m x 1-m plots were analyzed to find the saturated hydraulic conductivity, an indicator of infiltration capacity. I...

Many ponderosa pine and mixed-conifer forests of the western, interior United States have undergone substantial structural and compositional changes since settlement of the West by Euro-Americans. Historically, these forests consisted of widely spaced, fire-tolerant trees underlain by dense grass swards. Over the last 100 years they have developed into dense stands consisting of more fire-sensitive and disease-susceptible species. These changes, sometimes referred to as a decline in 'forest health’, have been attributed primarily to two factors: active suppression of low-intensity fires...

Variation in the distribution of species richness as a result of introduced errors of omission and commission in the Gap Analysis database for Oregon was evaluated using Monte Carlo simulations. Random errors, assumed to be independent of a species' distribution, and boundary errors, assumed to be dependent on the species' distribution, were simulated using ten rodent species. Error rates of omission and commission equal to 5 and 20 percent were used in the simulations. Indications are that predictions of species richness within a Gap Analysis database can be very sensitive to both types...