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Collaboration has taken root in national forest planning, providing expanded opportunities for stakeholder participation in decision-making, but are these processes considered meaningful by key stakeholders? Do the processes result in increased participation by key stakeholders? We present results of a study of stakeholder perspectives of a collaborative planning process on the Grand Mesa, Uncompahgre, and Gunnison National Forests in Western Colorado, U.S.A. The stakeholders were stratified by participation levels in order to explore a possible relationship between participation and perceptions of the collaborative process. We used a Q-methodology approach to compare and contrast perspectives across participant...
Abstract (from http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0102996): Trees are essential to urban habitats because they provide services that benefit the environment and improve human health. Unfortunately, urban trees often have more herbivorous insect pests than rural trees but the mechanisms and consequences of these infestations are not well documented. Here, we examine how temperature affects the abundance of a scale insect, Melanaspis tenebricosa (Comstock) (Hemiptera: Diaspididae), on one of the most commonly planted street trees in the eastern U.S. Next, we examine how both pest abundance and temperature are associated with water stress, growth, and condition of 26 urban street trees....
Abstract (from http://www.plosone.org/article/info:doi/10.1371/journal.pone.0059687): Cities profoundly alter biological communities, favoring some species over others, though the mechanisms that govern these changes are largely unknown. Herbivorous arthropod pests are often more abundant in urban than in rural areas, and urban outbreaks have been attributed to reduced control by predators and parasitoids and to increased susceptibility of stressed urban plants. These hypotheses, however, leave many outbreaks unexplained and fail to predict variation in pest abundance within cities. Here we show that the abundance of a common insect pest is positively related to temperature even when controlling for other habitat...
Abstract (from http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0111669): Projected climate change at a regional level is expected to shift vegetation habitat distributions over the next century. For the sub-alpine species whitebark pine (Pinus albicaulis), warming temperatures may indirectly result in loss of suitable bioclimatic habitat, reducing its distribution within its historic range. This research focuses on understanding the patterns of spatiotemporal variability for future projected P.albicaulis suitable habitat in the Greater Yellowstone Area (GYA) through a bioclimatic envelope approach. Since intermodel variability from General Circulation Models (GCMs) lead to differing predictions...
Abstract (from http://link.springer.com/article/10.1007%2Fs10584-016-1608-2): Many recent changes in tree species distributions, mortality, and growth rates have been linked to changes in climate. Managing forests in the face of climate change will require a basic understanding of which tree species will be most vulnerable to climate change and in what ways they will be vulnerable. We assessed the relative vulnerability to climate change of 11 tree species in western North America using a multivariate approach to quantify elements of sensitivity to climate change, exposure to climate change, and the capacity to adapt to climate change. Our assessment was based on a combination of expert knowledge, published studies,...
Patterns of nitrogen (N) accumulation and turnover in riparian systems in semi-arid regions are poorly understood, particularly in those ecosystems that lack substantial inputs from nitrogen fixing vegetation. We investigated sources and fluxes of N in chronosequences of riparian forests along the regulated Green River and the free-flowing Yampa River in semi-arid northwestern Colorado. Both rivers lack significant inputs from N-fixing vegetation. Total soil nitrogen increased through time along both rivers, at a rate of about 7.8 g N m(-2) year(-1) for years 10-70, and 2.7 g N m(-2)year(-1) from years 70-170. We found that the concentration of N in freshly deposited sediments could account for most of the soil...
Abstract (from http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0099604): Across the globe, species distributions are changing in response to climate change and land use change. In parts of the southeastern United States, climate change is expected to result in the poleward range expansion of black mangroves ( Avicennia germinans) at the expense of some salt marsh vegetation. The morphology of A. germinans at its northern range limit is more shrub-like than in tropical climes in part due to the aboveground structural damage and vigorous multi-stem regrowth triggered by extreme winter temperatures. In this study, we developed aboveground allometric equations for freeze-affected black mangroves which...
Abstract (from http://link.springer.com/article/10.1007%2Fs10980-015-0217-1): Context Tree species distribution and abundance are affected by forces operating across a hierarchy of ecological scales. Process and species distribution models have been developed emphasizing forces at different scales. Understanding model agreement across hierarchical scales provides perspective on prediction uncertainty and ultimately enables policy makers and managers to make better decisions. Objective Our objective was to test the hypothesis that agreement between process and species distribution models varies by hierarchical level. Due to the top-down approach of species distribution models and the bottom-up approach of process...
Global climatic change is expected to affect growth and survival of trees and will likely change the geographical distribution of many temperate and boreal tree species. Models that calculate the effects of environmental factors, as well as biotic factors, such as intra- and interspecific competition, on growth and survival of trees have been widely used to calculate the potential effects of temperature changes on tree populations. The methods to calculate thermal effects in such models are described and analyzed for the soundness and consistency of underlying assumptions. They are compared to the evidence from studies of tree physiology, growth, and biogeography. The use of thermal indices, especially temperature...
Strontium isotope sourcing has become a common and useful method for assigning sources to archaeological artifacts. In Chaco Canyon, an Ancestral Pueblo regional center in New Mexico, previous studies using these methods have suggested that significant portion of maize and wood originate in the Chuska Mountains region, 75 km to the East. In the present manuscript, these results were tested using both frequentist methods (to determine if geochemical sources can truly be differentiated) and Bayesian methods (to address uncertainty in geochemical source attribution). It was found that Chaco Canyon and the Chuska Mountain region are not easily distinguishable based on radiogenic strontium isotope values. The strontium...
Categories: Publication; Types: Citation; Tags: Agriculture, Anthropology, Archaeology, Archaeometry, Atoms, All tags...
Abstract (from http://rspb.royalsocietypublishing.org/content/282/1806/20142608): The amount of energy consumed within an average city block is an order of magnitude higher than that consumed in any other ecosystem over a similar area. This is driven by human food inputs, but the consequence of these resources for urban animal populations is poorly understood. We investigated the role of human foods in ant diets across an urbanization gradient in Manhattan using carbon and nitrogen stable isotopes. We found that some—but not all—ant species living in Manhattan's most urbanized habitats had δ13C signatures associated with processed human foods. In particular, pavement ants ( Tetramorium sp. E) had increased levels...
    map background search result map search result map Why won't they come? Stakeholder perspectives on collaborative national forest planning by participation level. Why won't they come? Stakeholder perspectives on collaborative national forest planning by participation level.