Treesearch

A seed-feeding weevil introduced to North America (NA) as a biological control agent of the invasive toadflax Linaria dalmatica (L.) Mill., identified then as Gymnetron antirrhini “Dalmatian host race” and subsequently confirmed as established, was revealed through our study to be a separate species, i.e., Rhinusa dieckmanni (Behne) (Coleoptera: Curculionidae). This weevil species was presumed to be endemic in its native range, with a distribution restricted to Mount Rila in southwestern Bulgaria. We conducted a comprehensive study of seedfeeding weevils associated with L. dalmatica, L....

Fuel and wildfire management decisions related to fuel break construction, maintenance, and use in fire suppression suffer from limited information on fuel break success rates and drivers of effectiveness. We built a dataset of fuel break encounters with recent large wildfires in Southern California and their associated biophysical, suppression, weather, and fire behavior characteristics to develop statistical models of fuel break effectiveness with boosted regression. Our results suggest that the dominant influences on fuel break effectiveness are suppression, weather, and fire behavior....

Background: Estimating the factors affecting the probability of a wildfire reaching the wildland urban interface (WUI) can help managers make decisions to prevent WUI property loss. This study compiles data on fire progression, wind, landscape characteristics, and fireline built to estimate the probability of an active fire reaching nearby WUI blocks. We started by constructing funnel-shaped analysis zones between recorded fire perimeters and WUI blocks. We used zonal analysis to characterize landscape and fireline arrangement and then used a random forest modeling approach to quantify the...

Patterns of spatial heterogeneity in forests and other fire-prone ecosystems are increasingly recognized as critical for predicting fire behavior and subsequent fire effects. Given the difficulty in sampling continuous spatial patterns across scales, statistical approaches are common to scale from plot to landscapes. This study compared the performance of four spatial interpolation methods (SIM) for mapping fine-scale fuel loads: classification (CL), multiple linear regression (LR), ordinary kriging (OK), and regression kriging (RK). These methods represent commonly used SIMs and demonstrat...

Ecologists are increasingly relying on national forest inventories to address a wide variety of issues. The ‘FIESTA’ R package (Forest Inventory ESTimation and Analysis) is a tool that enables customized investigations using the extensive sample-based inventory data collected across all lands in the US by the US Dept of Agriculture, Forest Service, Forest Inventory and Analysis (FIA) Program. To date, the complex nature of the FIA inventory constrains many users to conduct only limited analyses through existing tools with pre-specified geographic boundaries, timeframes, and auxiliary data...

Anthropogenic climate change is warming global temperatures, with significant implications for salmonid fishes that depend on the availability of cold water during one or more life stages. Along the southern range extents of many species, and elsewhere that warm temperatures are increasingly problematic, identification and protection or restoration of habitats that may serve as climate refugia where local populations can persist is emerging as an important conservation tactic. In this perspective piece, we address the concept and utility of climate refugia - drawing a distinction with the...

Maintaining natural thermal regimes in montane stream networks is critical for many species, but as climate warms, thermal regimes will undoubtedly change. Mitigating impacts of changing thermal regimes on freshwater biodiversity requires knowledge of which elements of the thermal regime are limiting factors for aquatic biota. We used full-year stream temperature records sampled across a broad latitudinal gradient to describe the diversity of the thermal landscapes that bull trout (Salvelinus confluentus) occupy and identify potential divergences from thermal regimes where this species has...

1. Moderate severity disturbances, those that do not result in stand replacement, play an essential role in ecosystem dynamics. Despite the prevalence of moderate severity disturbances and the significant impacts they impose on forest functioning, little is known about their effects on forest canopy structure and how these effects differ over time across a range of disturbance severities and disturbance types. 2. Using longitudinal data from the National Ecological Observatory Network project, we assessed the effects of three moderate severity press disturbances (beech bark disease,...

Ecosystem “hot spots” and “hot moments”—respectively, places and times of disproportionately high biogeochemical activity—are an important and often invoked concept in ecosystem science. Despite the popularity of the concept, there is no standard approach to quantifying hot spots and hot moments, hindering progress in understanding the phenomenon. For example, lack of a standard quantitative approach hinders advances arising from synthesis across datasets and studies potentially representing different processes, ecosystem types, places, and times. We present an approach to quantifying hot...

Background: Wilderness areas are important natural laboratories for scientists and managers working to understand fire. In the last half-century, shifts in the culture and policy of land management agencies have facilitated the management practice of letting some naturally ignited fires burn, allowing fire to fulfill its ecological role and increasing the extent of fire-related research opportunities. With the goal of identifying the global scientific advances enabled by this paradigm shift in wilderness fire management, we conducted a systematic review of publications that either (1)...