Download or read book The Effect of Burn Severity on Short term Boreal Vegetation Recovery in Interior Alaska written by Jared Wesley Oyler and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Remote Sensing of Burn Severity and the Interactions Between Burn Severity Topography and Vegetation in Interior Alaska written by Justin Frederick Epting and published by . This book was released on 2004 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A variety of single-band, band ratio, vegetation index, and multivariate algorithms were evaluated for mapping burn severity using Landsat TM and ETM+ imagery across four burns in interior Alaska. The Normalized Burn Ratio (NBR) outperformed all algorithms, both when tested as a single post-fire value and when tested as a differenced (prefire-postfire) value. The NBR was then used to map burn severity at a historical burn near Yukon-Charley Rivers National Preserve and a time-series of images from 1986 to 2002 was analyzed to investigate interactions between vegetation, burn severity, and topography. Strong interactions existed between vegetation and burn severity, but the only topographic variable that had a significant relationship with burn severity was elevation, presumably due to the strong control of elevation on vegetation type. The highest burn severity occurred in spruce forest, while the lowest occurred in broadleaf forest. Areas with high burn severity experienced disproportionately more shifts toward spruce woodland and shrub classes, while areas with low to moderate severity were less likely to change vegetation type. Finally, vegetation recovery, estimated using a remotely-sensed vegetation index, peaked between 8-14 years post-fire, and recovery was highest for areas with the highest burn severity"--Leaf iii.
Download or read book Interactions Among Climate Fire and Vegetation in the Alaskan Boreal Forest written by Paul Arthur Duffy and published by . This book was released on 2006 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The boreal forest covers 12 million km2 of the northern hemisphere and contains roughly 40% of the world's reactive soil carbon. The Northern high latitudes have experienced significant warming over the past century and there is a pressing need to characterize the response of the disturbance regime in the boreal forest to climatic change. The interior Alaskan boreal forest contains approximately 60 million burnable hectares and, relative to the other disturbance mechanisms that exist in Alaska, fire dominates at the landscape-scale. In order to assess the impact of forecast climate change on the structure and function of the Alaskan boreal forest, the interactions among climate, fire and vegetation need to be quantified. The results of this work demonstrate that monthly weather and teleconnection indices explain the majority of observed variability in annual area burned in Alaska from 1950-2003. Human impacts and fire-vegetation interactions likely account for a significant portion of the remaining variability. Analysis of stand age distributions indicate that anthropogenic disturbance in the early 1900's has left a distinct, yet localized impact. Additionally, we analyzed remotely sensed burn severity data to better understand interactions among fire, vegetation and topography. These results show a significant relationship between burn severity and vegetation type in flat landscapes but not in topographically complex landscapes, and collectively strengthen the argument that differential flammability of vegetation plays a significant role in fire-vegetation interactions. These results were used to calibrate a cellular automata model based on the current conceptual model of interactions among weather, fire and vegetation. The model generates spatially explicit maps of simulated stand ages at 1 km resolution across interior Alaska, and output was validated using observed stand age distributions. Analysis of simulation output suggests that significant temporal variability of both the mean and variance of the stand age distribution is an intrinsic property of the stand age distributions of the Alaskan boreal forest. As a consequence of this non-stationarity, we recommend that simulation based methods be used to analyze the impact of forecast climatic change on the structure and function of the Alaskan boreal forest"--Leaf iii.
Download or read book Permafrost Ecosystems written by Akira Osawa and published by Springer Science & Business Media. This book was released on 2010-01-04 with total page 507 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drawing from a decade-long collaboration between Japan and Russia, this important volume presents the first major synthesis of current knowledge on the ecophysiology of the coniferous forests growing on permafrost at high latitudes. It presents ecological data for a region long inaccessible to most scientists, and raises important questions about the global carbon balance as these systems are affected by the changing climate. Making up around 20% of the entire boreal forests of the northern hemisphere, these ‘permafrost forest ecosystems’ are subject to particular constraints in terms of temperature, nutrient availability, and root space, creating exceptional ecosystem characteristics not known elsewhere. This authoritative text explores their diversity, structure, dynamics and physiology. It provides a comparison of these forests in relation to boreal forests elsewhere, and concludes with an assessment of the potential responses of this unique biome to climate change. The book will be invaluable to advanced students and researchers interested in boreal vegetation, forest ecology, silviculture and forest soils, as well as to researchers into climate change and the global carbon balance.
Download or read book Ecological Effects of Forest Fires in the Interior of Alaska written by Harold John Lutz and published by . This book was released on 1956 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wildland Fire in Ecosystems written by and published by . This book was released on 2000 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alaska s Changing Boreal Forest written by F. Stuart Chapin and published by Oxford University Press. This book was released on 2006-01-12 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Boreal forest is the northern-most forest in the world, whose organisms and dynamics are shaped by low temperature and high latitude. The Alaskan Boreal forest is warming as rapidly as any place on earth, providing an opportunity to examine a biome as it adjusts to change. This book looks at this issue.
Download or read book Climate induced Changes in Ecological Dynamics of the Alaskan Boreal Forest written by Dana Rachel Nossov Brown and published by . This book was released on 2016 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: A warming climate is expected to cause widespread thawing of discontinuous permafrost, and the co-occurrence of wildfire may function to exacerbate this process. Here, I examined the vulnerability of permafrost to degradation from fire disturbance as it varies across different landscapes of the Interior Alaskan boreal forest using a combination of observational, modeling, and remote sensing approaches. Across all landscapes, the severity of burning strongly influenced both post-fire vegetation and permafrost degradation. The thickness of the remaining surface organic layer was a key control on permafrost degradation because its low thermal conductivity limits ground heat flux. Thus, variation in burn severity controlled the local distribution of near-surface permafrost. Mineral soil texture and permafrost ice content interacted with climate to influence the response of permafrost to fire. Permafrost was vulnerable to deep thawing after fire in coarse-textured or rocky soils throughout the region; low ice content likely enabled this rapid thawing. After thawing, increased drainage in coarse-textured soils caused reductions in surface soil moisture, which contributed to warmer soil temperatures. By contrast, permafrost in fine-textured soils was resilient to fire disturbance in the silty uplands of the Yukon Flats ecoregion, but was highly vulnerable to thawing in the silty lowlands of the Tanana Flats. The resilience of silty upland permafrost was attributed to higher water content of the active layer and the associated high latent heat content of the ice-rich permafrost, coupled with a relatively cold continental climate and sloping topography that removes surface water. In the Tanana Flats, permafrost in silty lowlands thawed after fire despite high water and ice content of soils. This thawing was associated with significant ground surface subsidence, which resulted in water impoundment on the flat terrain, generating a positive feedback to permafrost degradation and wetland expansion. The response of permafrost to fire, and its ecological effects, thus varied spatially due to complex interactions between climate, topography, vegetation, burn severity, soil properties, and hydrology. The sensitivity of permafrost to fire disturbance has also changed over time due to variation in weather at multi-year to multi-decadal time scales. Simulations of soil thermal dynamics showed that increased air temperature, increased snow accumulation, and their interactive effects, have since the 1970s caused permafrost to become more vulnerable to talik formation and deep thawing from fire disturbance. Wildfire coupled with climate change has become an important driver of permafrost loss and ecological change in the northern boreal forest. With continued climate warming, we expect fire disturbance to accelerate permafrost thawing and reduce the likelihood of permafrost recovery. This regime shift is likely to have strong effects on a suite of ecological characteristics of the boreal forest, including surface energy balance, soil moisture, nutrient cycling, vegetation composition, and ecosystem productivity.
Download or read book Studies by the U S Geological Survey in Alaska 2001 written by John P. Galloway and published by . This book was released on 2003 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Remote Sensing of Hydrometeorological Hazards written by George P. Petropoulos and published by CRC Press. This book was released on 2017-11-02 with total page 507 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extreme weather and climate change aggravate the frequency and magnitude of disasters. Facing atypical and more severe events, existing early warning and response systems become inadequate both in scale and scope. Earth Observation (EO) provides today information at global, regional and even basin scales related to agrometeorological hazards. This book focuses on drought, flood, frost, landslides, and storms/cyclones and covers different applications of EO data used from prediction to mapping damages as well as recovery for each category. It explains the added value of EO technology in comparison with conventional techniques applied today through many case studies.
Download or read book Fire Effects Guide written by and published by . This book was released on 1994 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understanding Northern Latitude Vegetation Greening and Browning written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2019-04-18 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vegetation change has been observed across Arctic and boreal regions. Studies have often documented large-scale greening trends, but they have also identified areas of browning or shifts between greening and browning over varying spatial extents and time periods. At the same time, though, there are large portions of these ecosystems that have not exhibited measurable trends in greening or browning. These findings have fueled many questions about the drivers of vegetation dynamics, how trends are measured, and potential implications of vegetation change at local to global scales. In December 2018, the National Academies of Sciences, Engineering, and Medicine, convened a workshop to discuss opportunities to improve understanding of greening and browning trends and drivers and the implications of these vegetation changes. The discussions included a close look at many of the methodological approaches used to evaluate greening and browning, as well as exploration of newer technologies that may help advance the science. This publication summarizes the presentations and discussions from the workshop.
Download or read book Fire Effects on Soils and Restoration Strategies written by A Cerda and published by CRC Press. This book was released on 2009-01-05 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book has been published a decade after Fires Effects on Ecosystems by DeBano, Neary, and Folliott (1998), and builds on their foundation to update knowledge on natural post-fire processes and describe the use and effectiveness of various restoration strategies that may be applied when human intervention is warranted. The chapters in this book,
Download or read book Wildfire Burn Susceptibility to Non native Plant Invasions in Black Spruce Forests of Interior Alaska written by Katie Lin Villano and published by . This book was released on 2008 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: "As the climate changes, Alaska's boreal forest faces the simultaneous threats of rising invasive plant abundances and increasing area burned by wildfire. Highly flammable and widespread black spruce forest represents a boreal habitat that may be increasingly susceptible to non-native plant invasion. In other biomes, non-native plant invasions are generally greatest in high severity burns that are only a few years old. The relationship between fire and non-native plant invasion has not been investigated in the northern boreal forest. To assess the invasibility of burned black spruce forests, I used burned field sites that spanned a gradient of burn severities, moisture levels, and burn ages. I conducted both field surveys and a greenhouse experiment using soil taken from burn sites. Contrary to generalizations from other biomes, I found soils from low severity burns and burns between 10 and 20 years old support greater invasive plant growth in black spruce forests than do high severity and more recent burns. In addition, regional differences between burn complexes outweighed burn severity and site moisture in determining the invasibility of burned black spruce sites. Finally, rebounding native vegetation appears to offer burned areas a level of resistance to invasive plant establishment"--Leaf iii.
Download or read book The Effects of Fire Severity and Site Moisture on Species Composition and Functional Properties of Black Spruce Forests in Interior Alaska written by Emily Louise Bernhardt and published by . This book was released on 2008 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In interior Alaska black spruce forest succession and vegetation properties are tightly linked to fire disturbance, partly due to the functional properties of species. Climatically induced changes in the fire regime could negatively affect some functional groups and potentially lower the functional diversity of stands through changes in fire severity and site moisture. In addition, there is little information regarding the relationship between pre- and post-fire community composition in black spruce communities of interior Alaska. To contribute to our knowledge regarding post-fire plant community dynamics, I investigated how post-fire community properties in relation to fire severity and site moisture: 1) species composition, in which pre- and post- fire community composition was compared to determine changes in species richness and functional diversity and 2) the functional traits of species. Pre- fire species composition in black spruce forests was dominated by late successional understory species and was most similar in species composition to low severity burned sites (regardless of stand age). Site moisture did not appear to affect the change in species composition post-fire in the first two years following fire. Functional groups that showed significant changes post-fire were bryophytes, lichen and evergreen shrubs. When each species was deconstructed into a set of functional traits, I observed that these traits were tightly linked to fire severity. These results have large implications under projected climate scenarios that predict increasing fire extent and severity in the boreal forest because high severity fire changes the species composition and associated functional traits of black spruce post-fire communities in interior Alaska"--Leaf iii.
Download or read book Ecology of Wildfire Residuals in Boreal Forests written by Ajith Perera and published by John Wiley & Sons. This book was released on 2014-07-21 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Large and intense wildfires are integral to the globally important boreal forest biome. While much is known about boreal wildfires, the focus on forest remnants that either escape or survive these intense fires is a recent phenomenon: academics now study ecological processes of wildfire residuals, forest policymakers use their patterns to design harvest strategies, forest managers consider their economic value, and conservationists recognize their intrinsic ecological importance. Ecology of Wildfire Residuals in Boreal Forests is the first book to explore ecological patterns and processes of what does not burn within boreal wildfires. Following a brief introduction to the boreal forest biome, it discusses the processes that form wildfire residuals; how they are studied, with various approaches and methods; the types, extent, and ecological functions of wildfire residuals; and their role in forest management applications, all in the context of ecological scale. This book is a reference for researchers and graduate students studying boreal forest ecology, as well as for policymakers and forest managers. It adopts a non-reductionist perspective that will be of interest to scientists from conservation science, forest ecology, forest management, and timber production. Brings together fire behaviour, ecological scale, vegetation ecology, and conservation biology to provide a cross disciplinary, multi-scale, and an integrative discussion of forest fire residuals Captures the state of knowledge with a meta-analysis of research trends during the past few decades, with a comprehensive review of the literature, a compilation of key references, and a list of key topics relevant to the study of boreal wildfire residuals Identifies the major gaps and uncertainties in the present body of knowledge, including a critique of study techniques and reporting practices to date, and proposes a set of terms and definitions and a list of research questions and priorities Includes the authors’ observations and research experience from boreal Canada, and information extracted from interactions with North American and European ecologists, forest managers, and conservationists
Download or read book U S Geological Survey Professional Paper written by and published by . This book was released on 1984 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
