Treesearch

Climate change projections provided by global climate models (GCM) are generally too coarse for local and regional applications. Local and regional climate change impact studies therefore use downscaled datasets. While there are studies that evaluate downscaling methodologies, there is no study comparing the downscaled datasets that are actually distributed and used in climate change impact studies, and there is no guidance for selecting a published downscaled dataset. We compare five widely used statistically downscaled climate change projection datasets that cover the conterminous USA...

Quantifying above-ground biomass changes, DAGB, is key for understanding carbon dynamics. National Forest Inventories, NFIs, aims at providing precise estimates of DAGB relying on model-assisted estimators that incorporate auxiliary information to reduce uncertainty. Poststratification estimators, PS, are commonly used for this task. Recently proposed endogenous poststratification, EPS, methods have the potential to improve the precision of PS estimates of DAGB. Using the state of Oregon, USA, as a testing area, we developed a formal comparison between three EPS methods, traditional PS...

The potential for trophic cascades triggered by recent range expansion of the Barred Owl (Strix varia) to the Pacific Northwest has caused concern among conservationists and managers. Barred Owl predation of small forest carnivores is a particular concern because these carnivores typically have low population growth rates relative to their body size owing to long interbirth intervals, which may result in sensitivity to increased mortality. The Western Spotted Skunk (Spilogale gracilis) is a common small carnivore in forests of the Pacific Northwest that may be a prey item for Barred Owls,...

1. Deep soil water utilization allows plants to cope with drought stress. However, little is known about the roles of the understorey layers in driving spatio-temporal variations of deep soil water in forests and how the patterns of deep soil water use among life-forms contribute to community assembly processes.2. We assessed the spatio-temporal patterns and determinants of deep water utilization of tree, shrub and herb layers in subtropical coniferous plantations and investigated associations between deep water use parameters and dominance and richness of understorey vegetation.3. We...

Understanding and predicting the relationship between leaf temperature (Tleaf) and air temperature (Tair) is essential for projecting responses to a warming climate, as studies suggest that many forests are near thermal thresholds for carbon uptake. Based on leaf measurements, the limited leaf homeothermy hypothesis argues that daytime Tleaf is maintained near photosynthetic temperature optima and below damaging temperature thresholds. Specifically, leaves should cool below Tair at higher temperatures (i.e., > ∼25–30°C) leading to slopes <1 in Tleaf /Tair relationships and substantial...

The Swift Terrestrial Passive Acoustic Recording Unit from The Cornell Lab of Ornithology, running firmware v. STM32 0.18.6.3, produced an initial 4-sec sound anomaly in each sound (wave file) recording, created by the power-saving features of the unit as it switches from standby to record mode. The sound anomaly had a statistically significant impact on several soundscape indices calculated from the recordings. Here, as a case study of identifying and solving this problem, I dissected the nature of the anomaly and analyzed the variable effects it has on calculated ecoacoustic soundscape...

Natural history is the study of organisms in their environments, and has an historic role as the foundation for ecological and biological sciences (e.g., Jerdon 1874). The centrality of natural history was emphasized by Elton (1927) who defined ecology as “scientific natural history.” As an accounting of the “history” of nature, natural history studies entail personal involvement; indeed, even the etymology of “history” suggests seeing, knowing, and accounting of one's inquiries and knowledge ( www.etymonline.com). In this paper, we trace the use and the scientific and social values of...

We investigated the relative importance of daily fire weather, landscape position, climate, recent forest and fuels management, and fire history to explaining patterns of remotely-sensed burn severity - as measured by the Relativized Burn Ratio - in 150 fires occurring from 2001 to 2019, which burned conifer forests of northeastern Washington State, USA. Daily fire weather, annual precipitation anomalies, and species' fire resistance traits were important predictors of wildfire burn severity. In areas burned within the past two to three decades, prior fire decreased the severity of...

When the fall rains begin, the water volume in coastal streams in the Pacific Northwest increases, allowing coho salmon (Oncorhynchus kisutch) to move upstream and spawn. The common wisdom for many years has been that this increase in stream discharge is the main trigger that signals it’s time for coho to begin their migration, build their redds (nests), and lay eggs, setting the stage for the next generation.But recent research by Rebecca Flitcroft with the USDA Forest Service Pacific Northwest Research Station shows that water volume is only half the equation. Coho salmon also need the...

Animal fear can be an important driver of ecological community structure: predators affect prey not only through predation, but also by inducing changes in behaviour and distribution—a phenomenon evocatively called the “ecology of fear.” The return of wolves to the western United States is a notable instance of such dynamics, yet plays out in a complex socioecological system where efforts to mitigate impacts on livestock rely on manipulating wolves' fear of people. Examining Washington state's efforts to affect wolf behaviour to reduce livestock predation, we argue that this approach to...