<p> Amphibians are important bioindicators in environmental assessment. This highly diverse group of vertebrates is experiencing unprecedented declines worldwide due to a complex array of factors, including disease, habitat loss, invasive species, and environmental pollution. Heavy metals are especially problematic due to their persistence and ability to present a localized hazard even at sublethal levels. Northern Idaho has a long history of mining activity, and many watersheds have experienced heavy metal contamination. These streams contain many sensitive species, including the Rocky Mountain Tailed Frog, <i> (Ascaphus montanus)</i>. While tailed frog populations are known to be especially vulnerable to logging and road building, the effects of local mining have not been documented. In order to assess the vulnerability of this species to heavy metal contamination, tadpoles were collected from three distinct populations across the Idaho Panhandle National Forest. Two sampling sites (Gold Creek and Beauty Creek) were characterized by abandoned mines in the headwaters of the streams, while a stream absent of any local historic mining (Bumblebee Creek) served as a reference site. Whole tadpoles were pooled and treated using EPA Method 3050B and analyzed for dissolved metal concentration (ug/g) using ICP-MS. We found the average metal concentrations in tadpoles (ug/g) at mining sites were generally higher than the reference site. Cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) were significantly higher in tadpoles at Gold Creek when compared with the reference site. These results are consistent with other studies indicating metals from historic mining activity are still evident in these stream communities.</p>

Smallholders in Southeastern Paraguay are threatened by the advance of mechanized farming, environmental degradation, and limited access to credit and inputs. Agroforestry initiatives have been proposed as a way to increase smallholder livelihood security in the face of such vulnerability. Yerba mate (Ilex paraguariensis) is a tree crop native to Paraguay that may be grown in agroforestry systems. While prices paid to farmers for yerba mate have increased in recent years, spurring interest and adoption of yerba mate production among some farmers, to this date, there have been no analyses of the effects that yerba mate production may have on livelihoods. This study, which was conducted April-July 2013 in the community of Libertad del Sur in Southeastern Paraguay, addresses this lack of research on yerba mate and livelihoods. Interviews were conducted with 23 households interested in cultivating yerba mate and six key informants on current livelihood strategies in Libertad del Sur and the potential effects of yerba mate production. Yerba mate production was found to be a profitable option for reducing certain sources of vulnerability, but the ability of households to invest in it was limited by several factors including high initial costs and lack of credit.

<p>For well over two decades, land management agencies in the U.S. have experienced trends of flat if not otherwise declining budgets with which to fulfill their respective missions. Consequently, public land management agencies at various levels have sought creative strategies such as using volunteers to extend quality services without incurring added expense. An increasingly popular form of multi-day volunteer engagements, often referred to as a volunteer vacation, is nearly absent from the literature when it comes to domestic project settings as opposed to international and often exotic locales.</p> <p>A qualitative research study was conducted in the summer of 2013 on volunteers participating in weeklong trail maintenance service-trips on National Forest land in Montana and Idaho. Two non-profit organizations (The Bob Marshall Wilderness Foundation and The Selway-Bitterroot Frank Church Wilderness Foundation) allowed researchers to conduct semi-structured interviews with 26 volunteers on their motives, experiences, preferences, and other aspects related to their overall volunteerism.</p> <p>Results suggest that respondents are motivated to participate for many reasons including: an environmental ethic, a social experience, personal development, immersion in nature, and receiving a facilitated backcountry experience. Understanding these motivations can assist managers and other nonprofits with capacity building objectives such as marketing and retaining volunteers.</p> <p>Other findings indicate volunteers acknowledge a high degree of self-interest with respect to preferences for project tasks, scheduling, and desired set of experiences before committing to service. This finding supports theories in the volunteerism literature suggesting that contemporary volunteering is trending towards the reflexive and away from the collective. This has recently been denoted by a preference for volunteer engagements that are concentrated and short-term (episodic) as opposed to ongoing (traditional).</p> <p>This study concludes with a proposal to expand the voluntourism definition to include domestic volunteer vacations in addition to the normative international volunteer vacation models. Also, a recommendation is issued to reconsider the prevailing set of associations for the new styles of volunteering. This comes from finding that episodic volunteers may also demonstrate many of the attributes of traditional volunteers such as a desire to form enduring ties to the organization.</p>

No description available.

<p> Amphibian species have experienced global declines since the 1970s and plethodontid salamanders are no exception. The green salamander, <i> Aneides aeneus,</i> is a plethodontid salamander that has experienced declines throughout its range in the Blue Ridge Escarpment. </p><p> Species distribution models are algorithms that predict occurrences of a species across a landscape and can be used to determine conservation priority areas. However, there are commonly only presence locations without corresponding absence locations available to a researcher. These presence-only datasets can present a challenge when trying to depict reliable distributions for a species of concern. Maximum Entropy (MaxEnt) is an algorithm empirically tested to model species distributions given presence-only datatsets. </p><p> I used landscape-level species distribution models including MaxEnt and logistic regression to model the occurrence of green salamanders across the Blue Ridge Escarpment of North Carolina. These models were used to assess particular features associated with <i>A. aeneus</i> presence as well used to search for new localities. </p><p> MaxEnt models outperformed logistic regressions for all methods of evaluation. MaxEnt models had fairly low omission (false negative) and commission (false positive) rates whereas my logistic regression had extremely high error rates for both. "Area Under the Receiver Operator Curve" evaluation scores were excellent (0.96) and good (0.81) for the top Maxent model and logistic regression, respectively. </p><p> <i>Aneides aeneus</i> is known to be associated with habitat that includes rock outcroppings with thin, deep crevices. My models indicated that forested areas, intermediate elevations, and shallow soils of particular types are desirable landscape features for <i>A. aeneus.</i> Soil was the most important variable in all models, accounting for almost half of the variation in MaxEnt models. Elevation accounted for most of the remaining variation. Percent canopy cover accounted for 4-6.5% of the variation in Maxent models. While these models did not specifically predict presence of outcrops, they were extremely helpful in identifying habitat with conditions supportive for <i>A. aeneus</i> if a rock outcrop was present. With the help of these models I discovered one previously unknown locality for <i> A. aeneus</i> and am confident addition locations can be found.</p>

Recent data shows that three quarters of nonresident vacationers to Montana are primarily attracted to characteristics of public lands such as national parks, mountains and forests, and open space. Thirty-five percent of Montana is public land, therefore understanding what values those visitors have for these public lands is very important and has not been analyzed in previous research. This study used panel survey methodology to identify a set of respondents who are not Montana residents but have visited the state. One component of the study used Borrie, Freimund, and Davenports National Parks Values Scale and Winters Natural Area Values Scale, as a basis for determining value statements. A mean value score for each of the 41 values statements relevant to Montanas public lands was identified. The study also identified recreation activity participation and public land visitation. A priori segmentation of user groups based on participation of these activities developed three cluster groups: non-motorized active, motorized, and passive. An analysis of variance identified value differences between the groups. Results indicate most respondents agreed with the value statements from the two scales. However, when the clustered groups were compared, there were 17 value items that showed significant differences. Using the Bonferroni post hoc test, the greatest differences were found between the non-motorized active and passive groups. With nonresident vacationers of 5.1 million visitors per year, identifying the values nonresident visitors have for Montanas public lands are important for understanding how values influence destination decision-making, how values influence recreation activity participation, and how tourism marketers can use values when developing marketing strategies.

Thesis (M.A., Landscape Architecture)--University of Arizona, 1990. / Includes bibliographical references.

Submitted to the Fletcher School of Law and Diplomacy. Thesis (Ph.D.)--Tufts University, 2002. / Adviser: William R. Moomaw. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 140-145).

Thesis (M.S.)--Wisconsin. / Includes bibliographical references (leaves 227-242).