Treesearch

Herbivory is a dominant feeding strategy among animals, yet herbivores are often protein limited. The gut microbiome is hypothesized to help maintain host protein balance by provisioning essential macromolecules, but this has never been tested in wild consumers. Using amino acid carbon (δ13C) and nitrogen (δ15N) isotope analysis, we estimated the proportional contributions of essential amino acids (AAESS) synthesized by gut microbes to five co-occurring desert rodents representing herbivorous, omnivorous and insectivorous functional groups. We found that herbivorous rodents occupying lower...

The synergistic effects of climate change, wildfires, fire suppression, and past forest management are challenging efforts to protect and recover Canada lynx (Lynx canadensis) in the North Cascades of Washington, USA. Canada lynx is a threatened species in the United States and a focal species used to gain insights into the structure and function of boreal forest ecosystems. To understand how multiple stressors are influencing lynx populations and the boreal forest in Washington, we developed a spatially explicit carrying capacity model in HexSim using local data on lynx resource selection...

In this study, we evaluated alternative methods for comparing the provision of ecosystem services among urban areas, stressing how the choice of comparison method affects the ability to compare the ecosystem service outcomes, in order to improve the management actions in urban green areas, reduce environmental inequality, and ensure satisfactory levels of human well-being. For the analysis, ten spatial indicators were quantified to assess the provision of urban ecosystem services in Barcelona, Spain, and Santiago, Chile. Two comparison methods were applied in both cities to evaluate the...

Background: Wildfires are increasing in incidence, size, and severity in the USA along with associated firefighting costs. Evaluation of firefighting containment and mop-up activities are crucial to reduce costs and to inform safe and effective wildfire response. As geospatial technologies advance, fireline effectiveness metrics have continued to be updated and improved. However, to develop standard analysis protocols and performance evaluations, there is a need to understand how widely metrics vary within and across fire events and are dependent on the different sources and accuracy of...

Phenology of diameter growth in trees has been studied for many years but generally using a limited number of sites and genotypes. In this project provenances of Douglas-fir (Pseudotsuga menziesii var. menziesii) planted across a wide range of environments were used to evaluate diameter growth and phenology to an extreme heat event and to seasonal conditions. Sampling was done in nine common gardens in western Oregon and Washington, USA that included a coastal site, a low elevation interior site, and high elevation interior site on three latitude bands. In 2021, three provenances at four...

Disturbances to forested watersheds often result in increases of nutrients and light to nearby streams. Such changes are generally expected to produce a shift to a more autotrophic aquatic ecosystem, with measurable increases in algae, and associated implications for food webs and fisheries. Although this paradigm is widely established, results from our 10-year study (2007–2016) in 12 headwater streams and four sites downstream in the Trask River Watershed (Oregon, USA), did not concur. In 2012, one watershed was thinned, three were clearcut harvested with variable buffers and three with...

With climate change and ongoing impacts from human development and resource extraction, US federal land management agencies are acutely concerned with managing for healthy aquatic ecosystems in the Southern Appalachian Mountain (SAM) Region. Here, we describe development of a spatial decision support application to assess the biological and ecological impacts of atmospheric S and N deposition on aquatic ecosystems of the region. We first summarize foundational published work to predict continuous maps of surface water acid neutralizing capacity (ANC) and soil base cation weathering (BCw)....

This is the executive summary for the report, Climate Change Vulnerability and Adaptation in the Columbia River Gorge National Scenic Area, Mount Hood National Forest, and Willamette National Forest, by Halofsky et al. (2022, PNW-GTR-1001). The vulnerability and adaptation assessment was conducted by a science-management partnership comprising of the three U.S. Department of Agriculture Forest Service units, Forest Service scientists, and other organizations. The partnership assessed the vulnerability of natural resources to climate change and developed adaptation options that minimize...

For many forest landscape ecology and ecological monitoring projects, forest structure and composition data availability at the correct scale are often limiting factors, motivating the development of map products based on remote sensing. Gradient nearest neighbor (GNN) imputation is a flexible framework for generating multivariate, annual, wall-to-wall maps of forest structure and composition for landscape, regional, and national applications. This report provides guidance on the appropriate use of forest structure and composition maps generated from satellite imagery, physical environment,...

Humans have lived from equator to poles for millennia but are now increasingly intruding into the wild spaces of other species and steadily extruding ourselves from our own wild spaces, with a profound impact on: our relationship with the natural world; survival of other species; pollution; climate change; etc. We have yet to grasp how these changes directly impact our own health. The primary focus of this paper is on the beneficial influence of proximity to the natural environment. We summarize the evidence for associations between exposure to green space and blue space and improvements...