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- This paper discusses the importance of cultural and institutional differences in rights of access to nature for sustainable tourism management. Drawing on the insights from the papers contained in this issue of the Journal of Sustainable Tourism, this introduction highlights two overarching themes. The first is the ambiguous/problematic role of science in establishing sustainable capacities for tourism's settings. Not only does this science rely on problematic assumptions of stable ecosystems, the idea of a science of sustainability presumes cultural and institutional capacities to...AuthorsDaniel R. WilliamsKeywordsSourceJournal of Sustainable Tourism. 9(5): 361-371.Year2001
- Almost any type of sample has some utility when estimating population quantities. The focus in this paper is to indicate what type or combination of types of sampling can be used in various situations ranging from a sample designed to establish cause-effect or legal challenge to one involving a simple subjective judgment. Several of these methods have little or no utility in the scientific area but even in the best of circumstances, particularly complex ones, both probabilistic and non-probabilistic procedures have to be used because of lack of knowledge and cost. We illustrate this with a...AuthorsH. T. Schreuder, T. G. Gregoire, J. P. WeyerKeywordsSourceEnvironmental Monitoring and Assessment. 66: 281-291.Year2001
- A number of different estimators can be used when forest inventory plots cover two or more distinctly different condition classes. In this article the properties of two approximate Horvitz- Thompson (HT) estimators, a ratio of means (RM), and a mean of ratios (MR) estimator are explored in the framework of double sampling for stratification. Relevant theoretical properties are given, and a simulation study is used to compare the properties of these estimators. It is concluded that the variance of the RM estimator is smaller than that of the approximate HT for the populations studied, but...AuthorsMichael S. WilliamsSourceForest Science. 47(4): 563-576Year2001
- For 2 populations of Nebraska sedge (Carex nebrascensis Dewey [Cyperaceae]), removal of the perigynium, the saclike structure around mature achenes, either with forceps or sandpaper, provided sufficient scarification to significantly increase total germination about 50% compared with that of nonscarified achenes. We also found that a combination of scarification and 32 d of cold, moist stratification resulted in 25% higher total germination than stratification alone. Stratification of scarified achenes with sphagnum peat moss resulted in 17% more germination than when scarified achenes...AuthorsJ. Chris Hoag, R. Kasten Dumroese, Michael E. SellersKeywordsSourceNative Plants Journal. 2(1): 63-66.Year2001
- Inventory data are often used to estimate the area of the land base that is classified as a specific condition class. Examples include areas classified as old-growth forest, private ownership, or suitable habitat for a given species. Many inventory programs rely on classification algorithms of varying complexity to determine condition class. These algorithms can be simple decision trees applied in the field or computer calculations applied on a field data recorder or after the data are collected. The advantages to using these algorithms are consistent classification of the condition class,...AuthorsMichael S. Williams, Hans T. Schreuder, Ray L. CzaplewskiSourceCanadian Journal of Forest Research. 31: 556-560.Year2001
- Spotted Knapweed (Centaurea maculosa) seeds were found in the pellets of Great Horned Owls (Bubo virginianus). That apparently resulted from owls preying upon Deer Mice (Peromyscus maniculatus) which had incidentally consumed knapweed seeds while foraging for the larvae of biological control agents within knapweed seedheads. Successful germination of 1% of the seeds shows that knapweed seeds recovered from owl pellets can be viable after being ingested by both species and suggest that Great Horned Owls can act as indirect dispersers of Spotted Knapweed seeds.AuthorsDean E. Pearson, Yvette K. OrtegaKeywordsSourceCanadian Field-Naturalist. 115(2): 354.Year2001
- Our objective was to document the effect of fire-history sampling on the mortality of mature ponderosa pine trees in Oregon. We examined 138 trees from which fire-scarred partial cross sections had been removed five to six years earlier, and 386 similarly sized, unsampled neighbor trees, from 78 plots distributed over about 5,000 ha. Mortality was low for both groups. Although mortality was significantly higher for the sectioned trees than their neighbors (8% versus I%), removing a partial section did not appear to increase a tree's susceptibility to death from factors such as wind or...AuthorsEmily K. Heyerdahl, Steven J. McKayKeywordsSourceTree-Ring Research. 57(2): 131-139.Year2001
- Loadings of downed woody fuels in pine-oak forests of the Madrean Province are heavier on sites in southeastern Arizona with low fire frequencies and lower on sites in northeastern Sonora, Mexico, with high fire frequencies. Low fire frequencies in southeastern Arizona are attributed largely to past land uses and the fire suppression policies of land management agencies in the United States. Ecologists and land managers interested in reintroducing fire into these forests to reduce fuel loadings and meet other land management objectives could use information about fuel buildups in their...AuthorsFrancisco J. Escobedo, Peter F. Ffolliott, Gerald J. Gottfried, Florentino GarzaKeywordsSourceResearch Note RMRS-RN-10. Fort Collins, CO: USDA-Forest Service, Rocky Mountain Research Station. 6 p.Year2001
- Agriculture and development have dramatically reduced the range of native bunchgrass habitats in the Northern Rocky Mountains, and the invasion of exotic plants threatens to greatly alter the remaining pristine prairie. Small mammals play many important roles in ecosystem functions, but little is known about small mammal community composition and structure in native bunchgrass habitats of the Northern Rocky Mountains. We live trapped small mammals along transects to study community composition, relative abundance, and habitat relationships in three native bunchgrass sites (Bandy Ranch,...AuthorsDean E. Pearson, Yvette K. Ortega, Kevin S. McKelvey, Leonard F. RuggieroSourceNorthwest Science. 75: 107-117.Year2001
- This paper examines the role of traditional religious beliefs and traditional leaders in conserving remnant patches of a unique type of dry forest in the Zambezi Valley of northern Zimbabwe. We examined aerial photographs spanning more than three decades, interviewed and surveyed local residents, and met with communities to learn about the environmental history of the forests and the factors that have affected land use in the area. Our results show that forest loss is dramatically less in forests that are now considered sacred, or were in the past connected to sacred forests. This supports...AuthorsBruce A Byers, Robert N. Cunliffe, Andrew T. HudakKeywordsSourceHuman Ecology. 29(2): 187-218.Year2001