Download or read book Impact of Wildfire on Annual Water Yield in Large Watersheds written by Sangki Lee and published by . This book was released on 2020 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Available studies on the effects of wildfire on water yield were conducted in small size watersheds (10km2) and little is known on the scalability of those findings to large watersheds. However, the frequency and occurrence of wildfires that burn large watersheds (100km2) have been increasing in the last decades, resulting on the need to predict their impacts on watershed hydrology. The impact of wildfire on watershed annual water yield is constrained by a complex interaction among several processes, which include hydrologic, geologic, ecologic, climatic alterations. This study investigates short- and long-term responses of annual water yield changes due to wildfire in large watersheds within a paired watershed framework. We, also, propose a new theoretical approach based on the Budyko framework to predict the change in annual water yield due to wildfires, which was originally proposed to explore alterations of water and energy balance within burned watersheds. Long-term responses of annual water yield were predicted by analyzing residuals between annual water yields measured in the field and estimated with paired watershed regression models. Paired watershed analyses were applied to 34 pairs between 11 burned watersheds and 8 unburned watersheds in the Salmon River and Payette River basin (Central Idaho USA), Yellowstone National Park (Wyoming, USA), and Klamath River basin (California, USA). The Budyko framework was conducted in 8 burned watersheds for 10 wildfires, were statistically significant from paired watershed analyses. The Budyko framework was applied both at the yearly time scale (one point for each year) and as originally developed as time averaged (one point for pre and one for post-fire period). This study employed (1) a simple linear model with evaporative index (AET/P) and (2) Fu [1981]'s equation with relative evaporative index (1-Q/P). Results show that annual water yield generally increases after wildfires that burned more than 10% of drainage area with negligible and undetectable changes for smaller burned areas. Exceptions to this trend are for watersheds whose hydrological system is dominated by baseflows (with large ground water storage) and those whose wildfire mainly burned short vegetation. Annual water yield tends to return toward pre-fire condition following the Kuczera's curve, which is related with changes in water demand following regrowth or resuccession of burned trees/vegetation. Post-fire annual water yield increased with burned area, and this correlation was more evident in Mediterranean than in arid climate regions. Post-fire change in annual water yield increases proportionally with drainage area in small watersheds, but this relationship is limited in large watersheds. Results of the Budyko framework show decrease in evapotranspiration rate in most burned watersheds. Reduction in evapotranspiration results in an increase of annual water yield. On the other hand, increase in evaporative index was detected in burned watershed where trees grew quickly during the post-fire period. Climatic conditions can affect the hydrological response during post-fire. Weather condition is an important factor for estimating the annual water yield responses against wildfire. Budyko framework shows that wildfire impact is mitigated under wet weather condition or enhanced under dry weather condition. Results of paired watershed analysis and Budyko framework show a good agreement that post-fire annual water yield responses are strongly correlated with changes in evapotranspiration rate associated with tree mortality or regrowth rate.

Download or read book Wildland Fire Impacts on Water Yield Across the Contiguous United States written by and published by . This book was released on 2019 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wildland fires in the contiguous United States (CONUS) have increased in size and severity, but much remains unclear about the impact of fire size and burn severity on water supplies used for drinking, irrigation, industry, and hydropower. While some have investigated large-scale fire patterns, long-term effects on runoff, and the simultaneous effect of fire and climate trends on surface water yield, no studies account for all these factors and their interactions at the same time. In this report, we present critical new information for the National Cohesive Wildland Fire Management Strategy—a first-time CONUS-wide assessment of observed and potential wildland fire impacts on surface water yield. First, we analyzed data from 168 fire-affected locations, collected between 1984 and 2013, with machine learning and used climate elasticity models to correct for the local climate baseline impact. Stream gage data show that annual river flow increased most in the Lower Mississippi and Lower and Upper Colorado water resource regions, however they do not show which portion of this increase is caused by fire and which portion results from local climate trends. Our machine learning model identified local climate trends as the main driver of water yield change and determined wildland fires must affect at least 19 percent of a watershed >10 km2 to change its annual water yield. A closer look at 32 locations with fires covering at least 19 percent of a watershed >10 km2 revealed that wildfire generally enhanced annual river flow. Fires increased river flow relatively the most in the Lower Colorado, Pacific Northwest, and California regions. In the Lower Colorado and Pacific Northwest regions, flow increased despite post-fire drought conditions. In southern California, post-fire drought effects masked the flow enhancement attributed to wildfire, meaning that annual water yield declined but not as much as expected based on the decline in precipitation. Prescribed burns in the Southeastern United States did not produce a widespread effect on river flow, because the area affected was typically too small and characterized by only low burn severity. In the second stage of the assessment, we performed full-coverage simulations of the CONUS with the Water Supply Stress Index (WaSSI) hydrologic model (88,000 HUC-12-level watersheds) for the period between 2001 and 2010. This enables us to fill in the gaps of areas with scarce data and to identify regions with large potential increases in post-fire annual water yield (+10 to +50 percent): mid- to high-elevation forests in northeastern Washington, northwestern Montana, central Minnesota, southern Utah, Colorado, and South Dakota, and coastal forests in Georgia and northern Florida. A hypothetical 20-percent forest burn impact scenario for the CONUS suggests that surface yield can increase up to +10 percent in most watersheds, and even more in some watersheds depending on climate, soils, and vegetation. The insights gained from this quantitative analysis have major implications for flood mitigation and watershed restoration, and are vital to forest management policies aimed at reducing fire impact risk and improving water supply under a changing climate.

Download or read book Estimating Postfire Water Production in the Pacific Northwest written by Donald F. Potts and published by . This book was released on 1989 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two hydrologic models were adapted to estimate postfire changer in water yield in Pacific Northwest watersheds. The WRENSS version of the simulation model PROSPER is used for hydrologic regimes dominated by rainfall: it calculates water available for streamflow onthe basis of seasonal precipitation and leaf area index. The WRENSS version of the simulation model WATBAL is used for hydrologic regimes dominated by snowfall; it calculates water available for streamflow based on seasonal precipitation, energy aspect and cover density. The PROSPER and WATBAL models estimate large postfire increases in water available for streamflow only for fires that have removed more than 50 percent of the leaf area are cover density, respectively. Guidelines for selecting appropriate models, and tables and figures for calculating postfire water yield are presented. This simulation approach should be useful for estimating long-term effects of fire on water production within the framework of land management planning.

Download or read book Forests Water Guidelines written by Great Britain. Forestry Commission and published by . This book was released on 1993 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work advises owners and managers how woodlands and forests influence the freshwater ecosystem, and gives guidance on how operations should be carried out in order to protect and enhance the water environment. The guidelines apply equally to forest enterprises and the private sector.

Download or read book Hydrologic Effects of a Changing Forest Landscape written by National Research Council and published by National Academies Press. This book was released on 2008-12-19 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: Of all the outputs of forests, water may be the most important. Streamflow from forests provides two-thirds of the nation's clean water supply. Removing forest cover accelerates the rate that precipitation becomes streamflow; therefore, in some areas, cutting trees causes a temporary increase in the volume of water flowing downstream. This effect has spurred political pressure to cut trees to increase water supply, especially in western states where population is rising. However, cutting trees for water gains is not sustainable: increases in flow rate and volume are typically short-lived, and the practice can ultimately degrade water quality and increase vulnerability to flooding. Forest hydrology, the study of how water flows through forests, can help illuminate the connections between forests and water, but it must advance if it is to deal with today's complexities, including climate change, wildfires, and changing patterns of development and ownership. This book identifies actions that scientists, forest and water managers, and citizens can take to help sustain water resources from forests.

Download or read book Role of Fire in Determining Annual Water Yield in Mountain Watersheds written by Phillip E. Farnes and published by . This book was released on 2000 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Regional Streamflow Response to Wildfire in California Watersheds written by and published by . This book was released on 2014 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: As every watershed and every wildfire event is unique, streamflow response to wildfire is only representative of the specific watershed and conditions that produced the response. Most post-fire streamflow change experiments involve single watersheds, which limits extrapolation of the results beyond the particular watershed examined. A comprehensive understanding of post-fire streamflow response is needed at a regional scale to improve water resources planning and ecosystem management in California. For this dissertation, the regional effect of wildfire was examined for two different components of the streamflow hydrograph; annual streamflow yield and baseflow recession rates. Annual streamflow is a key variable for streamflow management, but high variability in post-fire annual streamflow response at the watershed scale has limited predictions of post-fire annual streamflow response at the regional scale. Baseflow recession rates are an important tool for predicting low flows, yet little is known about how baseflow recession rates respond to wildfire at either watershed or regional scales. A mixed model was introduced to regionalize post-fire streamflow change. Mixed modeling is a statistical approach used to synthesize data containing a hierarchical structure, such as streamflow data pooled from multiple watersheds experiments. A parsimonious storage-discharge model was used to provide insight into the hydrologic processes controlling baseflow recession rates. Annual streamflow significantly increased following wildfire in California at a regional scale. This response was greatest in watersheds with higher percentages of watershed area burnt and during moderately wet years. The first-order control on baseflow recession rates in California was found to be inter-seasonal changes in antecedent storage, not wildfire. Baseflow recession rates were observed to decrease by up to an order of magnitude as antecedent storage levels increased, indicating a shift in the source of recession flows from small, quickly-recharged aquifers at the beginning of the wet season to large, seasonal aquifers as the wet season progressed. Following wildfire, baseflow recession rates significantly decreased at a regional scale, suggesting that the dominant hydrologic processes affected by fire were related to post-fire reductions in above-ground vegetation (e.g. decreased interception, decreased soil evapotranspiration, decreased groundwater evapotranspiration).

Download or read book Effects of Fire on Water written by Arthur R. Tiedemann and published by . This book was released on 1979 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book PHYSICAL HYDROLOGY written by S. LAWRENCE DINGMAN. and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Watershed Hydrology written by Vijay P. Singh and published by Allied Publishers. This book was released on 2003 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cumulative Watershed Effects of Fuel Management in the Western United States written by U.s. Department of Agriculture and published by Createspace Independent Pub. This book was released on 2012-10-19 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fire suppression in the last century has resulted in forests with excessive amounts of biomass, leading to more severe wildfires, covering greater areas, requiring more resources for suppression and mitigation, and causing increased onsite and offsite damage to forests and watersheds. Forest managers are now attempting to reduce this accumulated biomass by thinning, prescribed fire, and other management activities. These activities will impact watershed health, particularly as larger areas are treated and treatment activities become more widespread in space and in time. Management needs, laws, social pressures, and legal findings have underscored a need to synthesize what we know about the cumulative watershed effects of fuel management activities. To meet this need, a workshop was held in Provo, Utah, on April, 2005, with 45 scientists and watershed managers from throughout the United States. At that meeting, it was decided that two syntheses on the cumulative watershed effects of fuel management would be developed, one for the eastern United States, and one for the western United States. For the western synthesis, 14 chapters were defined covering fire and forests, machinery, erosion processes, water yield and quality, soil and riparian impacts, aquatic and landscape effects, and predictive tools and procedures. We believe these chapters provide an overview of our current understanding of the cumulative watershed effects of fuel management in the western United States. This document is the result of a major interdisciplinary effort to synthesize our understanding of the cumulative watershed effects of fuel management. This document is the product of more than 20 authors and 40 reviewers including scientists from four Forest Service Research Stations and numerous universities. Chapter topics include overviews of the effects of fuel management on both terrestrial and aquatic watershed processes.

Download or read book Wildland Fire in Ecosystems written by and published by . This book was released on 2005 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soil Water Repellency written by C.J. Ritsema and published by Elsevier. This book was released on 2012-12-02 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has become clear that soil water repellency is much more wide-spread than formerly thought. Water repellency has been reported in most continents of the world for varying land uses and climatic conditions. Soil water repellency often leads to severe runoff and erosion, rapid leaching of surface-applied agrichemicals, and losses of water and nutrient availability for crops. At present, no optimum management strategies exist for water repellent soils, focusing on minimizing environmental risks while maintaining crop production. The book starts with a historical overview of water repellency research, followed by seven thematic sections covering 26 research chapters. The first section discusses the origin, the second the assessment, and the third the occurrence and hydrological implications of soil water repellency. The fourth section is devoted to the effect of fire on water repellency, section five deals with the physics and modeling of flow and transport in water repellent soils, section six presents amelioration techniques and farming strategies to combat soil water repellency, and section seven concludes the book with an extensive bibliography on soil water repellency.

Download or read book Cumulative Watershed Effects of Fuel Management in the Western United States written by William J. Elliot and published by . This book was released on 2010 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Forest Hydrology written by Devendra Amatya and published by CABI. This book was released on 2016-09-14 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forests cover approximately 26% of the world's land surface area and represent a distinct biotic community. They interact with water and soil in a variety of ways, providing canopy surfaces which trap precipitation and allow evaporation back into the atmosphere, thus regulating how much water reaches the forest floor as through fall, as well as pull water from the soil for transpiration. The discipline "forest hydrology" has been developed throughout the 20th century. During that time human intervention in natural landscapes has increased, and land use and management practices have intensified. The book will be useful for graduate students, professionals, land managers, practitioners, and researchers with a good understanding of the basic principles of hydrology and hydrologic processes.

Download or read book Wildfire Effects on Net Precipitation Streamflow Regime and Rainfall runoff Events in Northern Rocky Mountain Watersheds written by Christopher Hart Stanley Williams and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent decades, severe wildfire in western North America has increased in frequency as a result of a warming climate and historical fire suppression, impacting an increasing amount of forested area. Reduced forest canopy interception and storage combined with soil water repellency and altered soil structure after wildfire can lead to greater runoff responses than in unburned forests. This has led to a proliferation of post-wildfire hydrological studies, mostly at the plot and hillslope scales, and mainly located in heavily impacted regions of the USA (e.g. Colorado, New Mexico, California). However, the more northern Rocky Mountain regions have also been subjected to warming and increased risk of wildfire. The eastern slopes of the Canadian Rocky Mountains provide a disproportionate amount of vital surface water supplies to the Prairie Provinces largely owing to high overwinter snow accumulation. Much less is known about post-wildfire hydrology and runoff response in these more northern, snow-dominated mountain regions. This study examined impacts from the 2003 Lost Creek wildfire on net precipitation, flow regimes, and storm rainfall-runoff events in Rocky Mountain watersheds in the Crowsnest Pass, Alberta, Canada. Net precipitation was studied in subalpine forest stands while flow regimes and storms were studied at the watershed scale. Four subalpine forest stands (two burned and two unburned reference) were used to measure rainfall interception and snow accumulation (SWE); net precipitation was derived from these measurements for the study period (2005-2014). Mean net precipitation was 274 mm (51%) greater in burned than in unburned reference forest stands. Greater mean snow accumulation (SWE) and net rainfall, respectively, constituted 152 and 122 mm of this total. Studies focused on post-wildfire flow regimes at varying time intervals (annual, monthly, weekly) were conducted during the 2nd to 11th years (2005-2014) after the wildfire. Streamflow and precipitation were measured in three burned and two unburned reference watersheds in a replicated post-hoc study design to enable comparisons. Flow regime studies highlighted greater magnitude and earlier timing of snowmelt runoff in wildfire-affected watersheds - April and May water yields were 100-200% and 40-50% higher, respectively, and half-flow dates arrived approximately 7-10 days earlier in burned compared to reference watersheds. The effects of wildfire on storm runoff during the snow-free season (late June to late September) was more ambiguous but flow responses in burned watersheds were proportionally greater, in general, than those in reference watersheds. However, post-wildfire storm runoff was surprisingly muted compared to that from other wildfire-affected regions and multiple regression analysis suggested fire accounted for

Download or read book Bulletin 163 written by Amy W. Lewis and published by . This book was released on 2018-07 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A paired basin study in the Upper Santa Fe River watershed following forest restoration has successfully measured water budget components in a treated and an untreated (control) basin. The paired basin study was established to investigate questions that have arisen with regards to changes in water yield from forest treatments. Precipitation, stream flow, soil moisture, and chloride concentrations in precipitation and stream flow were measured to quantify the water budget components. The results from nine years of data collection and analysis show a high degree of confidence with respect to measuring the water budget components based on the mass balance of water and chloride.