Treesearch

In April 2010, a multidisciplinary group of researchers and policy-makers met to discuss the state-of-the-science regarding the potential of roadside vegetation to mitigate near-road air quality impacts. Concerns over population exposures to traffic-generated pollutants near roads have grown with an increasing number of health studies reporting links between proximity to roads and adverse health effects. A recent EM article described how roadway design, including the presence of roadside vegetation, may be a means of mitigating air pollutant concentrations near roads. As a first step in...

The extent to which pretransplant colonization of seedlings with the arbuscular mycorrhizal fungus (AMF) Glomus aggregatum Schenck and Smith emend. Koske could enhance the post-transplant growth of two cultivars of Leucaena leucocephala (Lam.) de Wit (cv. K-8 and cv. K-636) in Al- and Mn-rich acid soils was evaluated in a greenhouse. Arbuscular mycorrhizal colonization measured at the end of the experiment was significantly stimulated by inoculation in both cultivars at all pH levels tested, although colonization was most stimulated if cv. K-8 was grown in the Al-rich soil at the lowest...

Managing wildfire events to achieve multiple management objectives involves a high degree of decision complexity and uncertainty, increasing the likelihood that decisions will be informed by experience-based heuristics triggered by available cues at the time of the decision. The research reported here tests the prevalence of three risk-based biases among 206 individuals in the USDA Forest Service with authority to choose how to manage a wildfire event (i.e., line officers and incident command personnel). The results indicate that the subjects exhibited loss aversion, choosing the safe...

Imposing user fees in Nature-Based Tourism (NBT) contexts has been a controversial issue. Based on the notions of justice and fairness, this study extended previous work examining the relationship between attitudes toward user fees and spending support. In a proposed structural model of price fairness, fee spending support, and willingness to pay (WTP), this paper identified the antecedents of WTP user fees, and empirically examined to what extent the data fit the model. Furthermore, the moderating role of place attachment in the model was investigated by using multiple-group structural...

We explored the effects of large magnitude flow fluctuations in rivers with dams, commonly referred to as pulsed flows, on tadpoles of the lotic-breeding Foothill Yellow-legged Frog, Rana boylii. We quantified the velocity conditions in habitats occupied by tadpoles and then conducted experiments to assess the tolerance to values at the upper limit of, and outside, the natural range. In laboratory flumes and field enclosures we mimicked the velocities observed during pulsed flows. In all experimental venues, the behavioral response of tadpoles was to seek refuge in the channel substrate...

Genetic data are increasingly being used in conservation planning for declining species. We sampled both the ecological and distributional limits of the foothill yellow-legged frog, Rana boylii to characterize mitochondrial DNA (mtDNA) variation in this declining, riverine amphibian. We evaluated 1525 base pairs (bp) of cytochrome b and ND2 fragments for 77 individuals from 34 localities using phylogenetic and population genetic analyses. We constructed gene trees using maximum likelihood and Bayesian inference, and quantified genetic variance (using AMOVA and partial Mantel tests) within...

This qualitative study explored conceptualizations of environmentalism and community, as well as the connections of ethnicity to these concepts in a small but diverse sample. Semistructured interviews were conducted with eight participants and included a conceptual content cognitive mapping procedure. The resulting maps were examined for themes and ideas about the key concepts and the connections between them. Participants' ideas about environmentalism reflected beliefs about social responsibility and environmental protection. Participants viewed community in a number of ways but generally...

Terrestrial carnivores typically have large home ranges and exist at low population densities, thus presenting challenges to wildlife researchers. We employed multiple, noninvasive survey methods—scat detection dogs, remote cameras, and hair snares—to collect detection–nondetection data for elusive American black bears (Ursus americanus), fishers (Martes pennanti), and bobcats (Lynx rufus) throughout the rugged Vermont landscape. We analyzed these data using occupancy modeling that explicitly incorporated detectability as well as habitat and landscape variables. For black bears, percentage...

An isolated population of the fisher (Martes pennanti) in the southern Sierra Nevada, California, is threatened by small size and habitat alteration from wildfires, fuels management, and other factors. We assessed the population’s status and conservation options for its habitat using a spatially explicit population model coupled with a fisher probability of occurrence model. The fisher occurrence model was selected from a family of generalized additive models (GAM) generated using numerous environmental variables and fisher detection–nondetection data collected at 228 survey arrays sampled...

The majority of genomic research in conifers has been conducted in the Pinus subgenus Pinus mostly due to the high economic importance of the species within this taxon. Genetic maps have been constructed for several of these pines and comparative mapping analyses have consistently revealed notable synteny. In contrast, little genomic research has been conducted on the Pinus subgenus Strobus, even though these pines have strong ecological relevance. We report a consensus genetic linkage map for sugar pine (Pinus lambertiana Dougl.) constructed with 399 single nucleotide polymorphisms...