Download Free Development Of A Spatial Severity Model For The Quantification Of Wildland Fire Effects In Coniferous Forests Book in PDF and EPUB Free Download. You can read online Development Of A Spatial Severity Model For The Quantification Of Wildland Fire Effects In Coniferous Forests and write the review.

Fire is an integral change agent in the Earth system and plays key roles in nutrient cycling, plant species distribution, atmospheric composition and ecosystem service function at temporal scales ranging from years to centuries and spatial scales ranging from micro to continental. Increased fire activity (intensity, frequency, and size) in North American forested ecosystems has been observed and predicted under warmer and drier climate conditions. As forested ecosystems serve as significant carbon sinks, there is an urgent need to improve our understanding of fire intensity impacts on forest productivity and recovery post-fire. The research within this dissertation is focused on advancing our current understanding by identifying mechanistic relationships between fire intensity and post-fire tree response (e.g. mortality, physiology, growth and vulnerability) that enable spatiotemporal characterization of fire effects. This research tested the hypothesis that increasing quantities, or 'doses', of fire intensity lead to predictable responses in terms of tree mortality or physiological function. This hypothesis was first tested using nursery grown Pinus contorta and Larix occidentalis seedlings subjected to highly controlled laboratory surface fires. A dose-response relationship was demonstrated between fire radiative energy and post-fire seedling mortality and physiological function. Additionally, this relationship was shown to be detectable using spectral indices common to plant physiology research. The dose-response hypothesis was further tested at the mature tree scale by using prescribed fires in mature Pinus ponderosa forest stands. Increasing levels of peak fire radiative power were observed to lead to reduced post-fire radial growth. Permanent defense structures, axial resin ducts, were found to increase in density, size, and area per growth ring post-fire regardless of fire intensity. Finally, observations from satellite based remote sensing were used to test the dose-response hypothesis at the landscape spatial scale. Similar to observations at the tree scale, satellite measures of forest productivity decreased with increasing fire radiative power. Species composition was demonstrated to influence the magnitude of productivity loss post-fire. Ultimately, the work in this dissertation demonstrates a framework to spatially characterize individual tree and forest condition post-fire, improving our understanding of the carbon cycle and ability to sustainably manage forests.
The objective of this study was to provide managers with national-level data on current conditions of vegetation and fuels developed from ecologically based methods to address these questions: How do current vegetation and fuels differ from those that existed historically? Where on the landscape do vegetation and fuels differ from historical levels? In particular, where are high fuel accumulations? When considered at a coarse scale, which areas estimated to have high fuel accumulations represent the highest priorities for treatment?
This book is a printed edition of the Special Issue "Fire Regimes: Spatial and Temporal Variability and Their Effects on Forests" that was published in Forests
The interaction between smoke and air pollution creates a public health challenge. Fuels treatments proposed for National Forests are intended to reduce fuel accumulations and wildfire frequency and severity, as well as to protect property located in the wild land-urban interface. However, prescribed fires produce gases and aerosols that have instantaneous and long-term effects on air quality. If fuels treatment are not conducted, however, then wild land fires become more severe and frequent causing worse public health and wellfare effects. A better understanding of air pollution and smoke interactions is needed in order to protect the public health and allow for socially and ecologically acceptable use of fire as a management tool. Wildland Fires and Air Pollution offers such an understanding and examines innovative wide-scale monitoring efforts (field and remotely sensed), and development of models predicting spatial and temporal distribution of air pollution and smoke resulting from forests fires and other sources. Collaborative effort of an international team of scientists High quality of invited chapters Full colour
Over the past century in the western United States, warming has produced larger and more severe wildfires than previously recorded. General circulation models and their ensembles project continued increases in temperature and the proportion of precipitation falling as rain. Warmer and wetter conditions may change forest successional trajectories by modifying rates of vegetation establishment, competition, growth, reproduction, and mortality. Many questions remain regarding how these changes will occur across landscapes and how disturbances, such as wildfire, may interact with changes to climate and vegetation. Forest management is used to proactively modify forest structure and composition to improve fire resilience. Yet, research is needed to assess how to best utilize mechanical fuel reduction and prescribed fire at the landscape scale. Human communities also exist within these landscapes, and decisions regarding how to manage forests must carefully consider how management will affect such communities. In this work, three aspects of forest management are analyzed: (1) climate effects on forest composition and wildfire activity; (2) efficacy of fuel management strategies toward reducing wildfire spread and severity; and, (3) local resident perspectives on forest management. Using a forest landscape model, simulations of forest dynamics were used to investigate relationships among climate, wildfire, and topography with long-term changes in biomass for a fire-prone dry-conifer landscape in eastern Oregon. Under climate change, wildfire was more frequent, more expansive, and more severe, and ponderosa pine expanded its range into existing shrublands and high-elevation zones. There was a near-complete loss of native high-elevation tree species, such as Engelmann spruce and whitebark pine. Loss of these species were most strongly linked to burn frequency; this effect was greatest at high elevations and on steep slopes. Fuel reduction was effective at reducing wildfire spread and severity compared to unmanaged landscapes. Spatially optimizing mechanical removal of trees in areas at risk for high-severity wildfire was equally effective as distributing tree removal across the landscape. Tripling the annual area of prescribed burns was needed to affect landscape-level wildfire spread and severity, and distributing prescribed burns across the study area was more effective than concentrating fires in high-risk areas. I conclude that forest management can be used to reduce wildfire activity in dry-mixed conifer forests and that spatially optimizing mechanical treatments in high-risk areas can be a useful tool for reducing the cost and ecological impact associated with harvest operations. While reducing the severity and spread of wildfire may slow some long-term species shifts, high sub-alpine tree mortality occurred under all climate and fuel treatment scenarios. Thus, while forest management may prolong the existence of sub-alpine forests, shifts in temperature, precipitation, and wildfire may overtake management within this century. The use of PPGIS was useful for delineating the range of forest management preferences within the local community, for identifying areas of agreement among residents who have otherwise polarized views, and for generating modeling inputs that reflect views that may not be obtained through extant official channels for public participation. Because the local community has concerns about the use of prescribed fire, more education and outreach is needed. This may increase public acceptance of the amounts of prescribed fire needed to modify wildfire trajectories under future climate conditions.
The book presents a wide range of techniques for extracting information from satellite remote sensing images in forest fire danger assessment. It covers the main concepts involved in fire danger rating, and analyses the inputs derived from remotely sensed data for mapping fire danger at both the local and global scale. The questions addressed concern the estimation of fuel moisture content, the description of fuel structural properties, the estimation of meteorological danger indices, the analysis of human factors associated with fire ignition, and the integration of different risk factors in a geographic information system for fire danger management.
This is a print on demand edition of a hard to find publication. Land management agencies (LMA) need to understand and monitor the consequences of their fire suppression decisions. The authors developed a framework for retrospective fire behavior modeling and impact assessment to determine where ignitions would have spread had they not been suppressed, and to assess the cumulative effects that would have resulted. This guidebook is used for applying this methodology and is for those interested in quantifying the impacts of fire suppression. Land managers who use this methodology can track the cumulative effects of suppression, frame future suppression decisions and cost-benefit analyses in the context of past experiences, and communicate tradeoffs to the public, non-gov. organ., and LMA.
A mathematical fire model for predicting rate of spread and intensity that is applicable to a wide range of wildland fuels and environment is presented. Methods of incorporating mixtures of fuel sizes are introduced by weighting input parameters by surface area. The input parameters do not require a prior knowledge of the burning characteristics of the fuel.