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Climate change and fire suppression have altered fire regimes globally, leading to larger, more frequent, and more severe wildfires. Responses of coldwater stream biota to single wildfires are well studied, but measured responses to consecutive wildfires in warmwater systems that often include mixed assemblages of native and nonnative taxa are lacking. We quantified changes in physical habitat, resource availability, and biomass of cold- and warmwater oligochaetes, insects, crayfish, fishes, and tadpoles following consecutive megafires (covering >100 km²) in the upper Gila River, New Mexico, USA. We were particularly interested in comparing responses of native and nonnative fishes that might have evolved under different disturbance regimes. Changes in habitat and resource availability were related to cumulative fire effects, fire size, and postfire precipitation. The 2nd of 2 consecutive wildfires in the basin was larger and, coupled with moderate postfire discharge, resulted in increased siltation and decreased algal biomass. Several insect taxa responded to these fires with reduced biomass, whereas oligochaete biomass was unaffected. Biomass of 6 of 7 native fish species decreased after the fires, and decreases were associated with site proximity to fire. Nonnative fish decreases after fire were most pronounced for coldwater salmonids, and warmwater nonnative fishes exhibited limited responses. All crayfish and tadpoles collected were nonnative and were unresponsive to fire disturbance. More pronounced responses of native insects and fishes to fires indicate that increasing fire size and frequency threatens the persistence of native fauna and suggests that management activities promoting ecosystem resilience might help ameliorate wildfire effects. [ABSTRACT FROM AUTHOR]

Recent major wildfires may result from a combination of climate change and fuel buildup due to fire exclusion policies of the last century. Are such fires unique to the forests and climate of the 21st century or are they similar to historic fires? Historic fires are recorded primarily by eye witness accounts which seldom contain information needed to examine them with modern fire management tools. The September 1, 1894 fire near Hinckley, Minnesota has well documented accounts from many survivors that allow position of the flame front to be established for a number of times throughout the fire. These accounts allowed us to calibrate a FARSITE model to represent the progression of that fire. FARSITE is a modern fire spread rate simulation model. It requires spatial layers of elevation, slope, aspect, timber type, derived layers of fuel type, canopy cover, stand height, canopy base height, canopy bulk density, duff and coarse woody debris. In this paper we will discuss how we were able to combine present GIS data, historical map data, and present ecosystem properties to provide data needed for these layers. GIS output of FARSITE spread predictions were used to match flame front position to eyewitness accounts and model parameters (primarily, wind speed and direction and fuel model spread rate adjustments) were altered to produce a flame front location and time that matched eyewitness location and timing. [ABSTRACT FROM AUTHOR]

Aim To quantify bird responses to a large unplanned fire, taking into consideration landscape-level fire severity and extent, pre-fire site detection frequency and environmental gradients. Location South-eastern Australia. Methods A major wildfire in 2009 coincided with a long-term study of birds and provided a rare opportunity to quantify bird responses to wildfire. Using hierarchical Bayesian analysis, we modelled bird species richness and the detection frequency of individual species in response to a suite of explanatory variables, including (1) landscape-level fire severity and extent (2) pre-fire detection frequency, (3) site-level vegetation density and (4) environmental variables (e.g. elevation and topography). Results Landscape-level fire severity had strong effects on bird species richness and the detection frequency of the majority of bird species. These effects varied markedly between species; most responded negatively to amount of severely burned forest in the landscape, one negatively to the amount of moderately burned forest and one responded negatively to the total area of burned forest. Only one species - the Flame Robin - responded positively to the amount of burned forest. Relationships with landscape-scale fire extent changed over time for one species - the Brown Thornbill - with initially depressed rates of detection recovering after just 2 years. The majority of species were significantly more likely to be detected in burned areas if they have been recorded there prior to the fire. Main conclusions Birds responded strongly to the severity and spatial extent of fire. They also exhibited strong site fidelity even after severe wildfire which causes profound changes in vegetation cover - a response likely influenced by environmental features such as elevation and topography. [ABSTRACT FROM AUTHOR]

Abstract: LANDFIRE is the working name given to the Landscape Fire and Resource Management Planning Tools Project (http://www.landfire.gov). The project was initiated in response to mega-fires and the need for managers to have consistent, wall-to-wall (i.e., all wildlands regardless of agency/ownership), geospatial data, on vegetation, fuels, and terrain to support use of fire behavior and effects prediction systems in guiding policy and management decisions. Base layers were created in a 5-year program of research and development ending in 2009, with processes in place to periodically update fuel and vegetation layers in response to anthropogenic and natural disturbances. LANDFIRE has been institutionalized as the primary data source for modeling activities aimed at meeting the goals of the United States’ National Cohesive Wildland Fire Management Strategy, and the data are available on-line to any user for conducting landscape analyses. Data access and use are high and expected to grow with the increasing scope and complexity of wildland fire management, thus requiring continued LANDFIRE improvements and updates. [Copyright &y& Elsevier]

Abstract: Central Yunnan, China was once dominated by evergreen broad-leaved forests. After a long period of destructive exploitation including agriculture development, overlogging for timber and cutting for fuelwood, these forests are being allowed to reestablish themselves. A large area is now dominated by the conifer Pinus yunnanensis forest which has naturally regenerated and represents an early intermediate stage in the reestablishment of the evergreen broad-leaved forest. In 2006, a mega-fire burned approximately 18.49km2 of this forest. The Pinus is growing back. To examine the process of regeneration dynamics and recovery of the Pinus community after the mega-fire, we investigated plant communities in burned and unburned areas, including a P. yunnanensis shrubland regenerated after the fire, a P. yunnanensis forest without fire occurrence, a P. yunnanensis and Lithocarpus mairei mixed forest, and a Castanopsis orthacantha and Lithocarpus dealbatus evergreen broad-leaved forest, as well as a plantation of P. yunnanensis. Abundant seedlings and saplings of P. yunnanensis and some light-demanding deciduous and evergreen broad-leaved tree species were found in the Pinus shrubland five years after the fire. The frequency distribution by height-classes after the fire was of an inverse-J type, representing very good regeneration. We used space-for-time substitution to obtain an understanding of the directions and pathways of the succession. The approximate successional trend in the area was from the Pinus shrubland to the Pinus forest, then to the mixed coniferous and evergreen broad-leaved Pinus–Lithocarpus forest, then to the evergreen broad-leaved Castanopsis–Lithocarpus forest. In the early successional stage, the floristic richness and species diversity of the Pinus shrubland had lower values as compared to those in the middle and late successional stages, but much higher than those of the Pinus plantation. Our results indicate that the natural recovery of P. yunnanensis after the fire was more efficient than that of a man-made forest of the same species. Nature’s process outpaced human intervention. [Copyright &y& Elsevier]