Treesearch

Wildfire suppression combines multiple objectives and dynamic fire behavior to form a complex problem for decision makers. This paper presents a mixed integer program designed to explore integrating spatial fire behavior and suppression placement decisions into a mathematical programming framework. Fire behavior and suppression placement decisions are modeled using nodes associated with cell centers from raster landscapes. The nodes at which suppression is located are determined by control variables. Response variables include fire spread paths, arrival times, and fireline intensities for...

Initial attack dispatch rules can help shorten fire suppression response times by providing easy-to-follow recommendations based on fire weather, discovery time, location, and other factors that may influence fire behavior and the appropriate response. A new procedure is combined with a stochastic programming model and tested in this study for designing initial attack dispatch rules integrated with development of seasonal suppression resource deployment decisions to support initial attack. Historical fires are spatially simulated according to historical weather and actual fire locations to...

Social interactions are widely recognized as a potential influence on risk-related behaviors. We present a mediation model in which social interactions (classified as formal/informal and generic-fire-specific) are associated with beliefs about wildfire risk and mitigation options, which in turn shape wildfire mitigation behaviors. We test this model using survey data from fire-prone areas of Colorado. In several cases, our results are consistent with the mediation hypotheses for mitigation actions specifically targeting vegetative fuel reduction. Perceived wildfire probability partially...

Modeling the behavior of crown fires is challenging due to the complex set of coupled processes that drive the characteristics of a spreading wildfire and the large range of spatial and temporal scales over which these processes occur. Detailed physics-based modeling approaches such as FIRETEC and the Wildland Urban Interface Fire Dynamics Simulator (WFDS) simulate fire behavior using computational fluid dynamics based methods to numerically solve the three-dimensional, time dependent, model equations that govern, to some approximation, the component physical processes and their interaction...

Research across a variety of risk domains finds that the risk perceptions of professionals and the public differ. Such risk perception gaps occur if professionals and the public understand individual risk factors differently or if they aggregate risk factors into overall risk differently. The nature of such divergences, whether based on objective inaccuracies or on differing perspectives, is important to understand. However, evidence of risk perception gaps typically pertains to general, overall risk levels; evidence of and details about mismatches between the specific level of risk faced...

The ability of landscapes to impede species’ movement or gene flow may be quantified by resistance models. Few studies have assessed the performance of resistance models parameterized by expert opinion. In addition, resistance models differ in terms of spatial and thematic resolution as well as their focus on the ecology of a particular species or more generally on the degree of human modification of the landscape (i.e. landscape integrity). The effect of these design decisions on model accuracy is poorly understood.

The impacts of climate extremes on terrestrial ecosystems are poorly understood but important for predicting carbon cycle feedbacks to climate change. Coupled climate-carbon cycle models typically assume that vegetation recovery from extreme drought is immediate and complete, which conflicts with the understanding of basic plant physiology. We examined the recovery of stem growth in trees after severe drought at 1338 forest sites across the globe, comprising 49,339 site-years, and compared the results with simulated recovery in climate-vegetation models.We found pervasive and substantial...

The new micro-dolichopodid genus Haromyia gen. nov. and the type species H. iviei sp. nov. are described from the island of Dominica in the Lesser Antilles. Males and females of Haromyia are distinguished by the large setae on a bulging clypeus, minute size, and wing veins that are nearly straight and evenly diverging from wing base. Haromyia does not fit readily into any contemporary dolichopodid subfamily, although it superficially resembles the Enliniinae and Achalcinae. Haromyia should be regarded as incertae sedis until the dolichopodid subfamilies can be refined, particularly to...

The purpose of this application, under Article 81.1 of the Code, is to conserve the genus-group names Liancalus Loew, 1857 and Scellus Loew, 1857 (Diptera, DOLICHOPODIDAE), widely distributed and well-established genera of dolichopodid flies whose names have been used consistently for more than one-and-ahalf centuries. They are threatened by a change in the type species of Anoplomerus Rondani, 1856, made in a largely-overlooked unpaginated corrigendum on the last page of Rondani (1856). Liancalus Loew, 1857 is a replacement name for the homonym Anoplomerus and automatically takes its type...

We have three goals. (1) To develop a suite of functionally relevant climate variables for modelling vegetation distribution on arid and semi-arid landscapes of the Great Basin, USA. (2) To compare the predictive power of vegetation distribution models based on mechanistically proximate factors (water deficit variables) and factors that are more mechanistically removed from a plant’s use of water (precipitation). (3) To quantify the climate gradients that control shrub distributions in a cold desert environment.