Treesearch

Catchment studies are foundational to hydrological and biogeochemical process understanding that has informed resource management, policy development and societal well-being (Burt and McDonnell 2015; Likens 2021; Tetzlaff et al. 2017). These place-based studies with sustained monitoring have shaped understanding of fundamental ecosystem processes and consequences of environmental change on ecosystems (Campbell et al. 2022; Hewlett, Lull, and Reinhart 1969; Jones et al. 2012; Latron and Lana-Renault 2018; Lovett et al. 2007; McNamara et al. 2018). The special issue, Research and Observatory...

Climate, forest successional stage, and soil substrate age can alter herbivore communities and their effects on biogeochemical cycling, but the size and spatial variability of these effects are poorly quantified. To address this knowledge gap, we established a globally distributed network of 50 broadleaved old-growth forests across six continents, encompassing well-constrained local-scale gradients in mean annual temperature (MAT), mean annual precipitation (MAP), succession, and soil substrate age. We used this network to investigate how these variables impact insect foliar herbivory and...

Critical flow theory provides a physical foundation for inferring discharge from measurements of wavelength and channel width made from images. In rivers with hydraulically steep local slopes greater than ∼0.01, flow velocities are high and the Froude number Fr (ratio of inertial to gravitational forces) can approach 1.0 (critical flow) or greater. Under these conditions, undular hydraulic jumps (UHJ's) can form as standing wave trains at slope transitions or constrictions. The presence of UHJ's indicates that mean Fr ≈ 1, implying that the velocity and depth of the flow and the spacing of...

The Central Appalachian region contains several high-elevation endemic woodland salamanders, which are thought to be particularly vulnerable to climate change due to their restricted distributions and low vagility. In West Virginia, there is a strong management focus on protection and recovery of the federally threatened Cheat Mountain salamander Plethodon nettingi. To support this focus, there is a need for improved understanding of the occurrence–habitat relationships and spatially explicit projections of fine-scale contemporary and potential future habitat quality to inform management...

Hydrologists commonly use climate metrics to understand watershed function and streamflow response due to their widespread availability and effectiveness in hydrologic models used to predict streamflow. This is particularly true in research aimed at characterising how streamflow response varies under changing climate conditions. In semi-arid to arid environments, researchers typically hypothesise that in drier, warmer years, vegetation and streamflow are in direct competition for stored water. Conceptual models suggest that seasonal plant water use and evapotranspiration (ET) can ultimately...

Bees are essential pollinators in many natural and agricultural systems and declines of some species are well-documented. Threats to bees include habitat loss and degradation and uncertainty remains about how management practices influence bee communities. Globally, ungulates are common in many systems and though numerous studies have examined livestock effects on bees, native ungulate effects on bees are poorly studied. In the western US, two native ungulates, deer (Odocoileus spp.) and elk (Cervus canadensis), are widespread and may occupy large annual home ranges. Public land managers...

Developing conservation strategies for species vulnerable to the effects of climate change, like polar bears (Ursus maritimus), can be challenging given the uncertainty of future environmental conditions. Effective conservation planning requires identifying and ranking threats to the persistence of polar bears throughout their circumpolar range and then assessing the ability of mitigative actions to aid in meeting plan objectives. We used a Bayesian network model to (1) characterize the relative importance of multiple biotic and anthropogenic stressors on four ecoregional polar bear...

Estimating the key demographic parameters of animal populations can enhance our understanding of system dynamics and assist in developing and improving conservation decision–support models. The Rio Grande cooter Pseudemys gorzugi is a conservation reliant freshwater turtle native to lower Rio Grande River Basin (USA and Mexico), with limited knowledge regarding its natural history and population dynamics. In this study, we used seven years of capture–mark–recapture data from the northern edge of the species’ range to estimate survival probabilities, changes in abundance, and the probability...

Spruce beetle (Dendroctonus rufipennis(Kirby)) is a major cause of spruce (Picea spp.) mortality in western North America. We synthesized the literature on the chemical ecology of spruce beetle, focusing on efforts to reduce host tree losses. This literature dates back to the mid-20th century and focuses on spruce beetle populations in Alaska, U.S., western Canada, and the central and southern Rocky Mountains, U.S. Spruce beetle aggregation pheromone components include frontalin (1,5-dimethyl-6,8-dioxabicyclo[3.2.1]octane), seudenol (3-methyl-2-cyclohexen-1-ol), MCOL (1-methyl-2-cyclohexen-...

Validation studies of the Forest Vegetation Simulator (FVS), a stand projection model widely used to predict carbon outcomes of alternative forest management strategies, have found departures from observed forest growth for several FVS variants in the western USA. We evaluated the accuracy of stand-level biomass accumulation predicted by FVS across an environmental gradient represented by three > 2 million ha landscapes that overlap seven FVS variants in Oregon, USA and the extent to which commonly deployed calibrations could correct for any departures. Calibrations included: growth...