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A draft decision framework for the National Park Service Interior Region 5 bison stewardship strategy

The Department of the Interior Bison Conservation Initiative calls for its bureaus to plan and implement collaborative American bison conservation and to ensure involvement by tribal, state, and local governments and the public in that conservation. Four independently managed and geographically separated National Park Service (NPS) units in Interior Region 5 (IR5) preserve bison and other components of a formerly contiguous Great Plains landscape. Management of bison in IR5 parks has historically been specific to each park, and livestock and range management science informed much of the decision making. In the past two decades, NPS has shifted away from managing bison from this livestock-based perspective towards a wildlife stewardship approach, including ensuring their long-term adaptive potential and considering them as just one part of a complex ecosystem. This shift requires a more holistic and cooperative approach to stewardship that is challenging not only because of limitations in funding and fluctuations in leadership priorities, but also because of the constraints imposed by the parks’ relatively small, fenced areas. The IR5 NPS Bison Stewardship Strategy (“Strategy”) will help the NPS to meet its responsibilities in cooperative stewardship of bison. The Strategy will serve to organize and consolidate the NPS’s legal and policy responsibilities within a framework of collectively defined values and objectives to support the careful and transparent decision-making processes that both guide and transcend park-specific planning. This report describes a preliminary decision framework for the Strategy, including the context, the fundamental objectives, and a range of alternative strategies developed and considered through two workshops and a series of conference calls with NPS personnel, stakeholders, and outside experts with an interest in IR5 NPS bison stewardship. Although not the Strategy itself, this framework serves as the Strategy’s starting point and identifies 14 fundamental objectives, falling in four major themes: Persistence of Wild and Healthy Bison 1. Maximize the long-term persistence of bison in IR5 parks 2. Maximize the long-term adaptive capacity of bison in North America 3. Maximize the wildness of the bison herds 4. Maximize humane treatment of bison, while allowing natural processes to occur Supporting Tribal Buffalo Culture 5. Improve relationships, trust, and communication with Tribes to enhance shared stewardship of bison within and beyond IR5 6. Maximize the number of live, healthy bison that can be transferred to tribal herds Persistence of Native Ecological Communities and Processes 7. Maximize structural and compositional heterogeneity of native prairie plant communities across space and time within each park 8. Maximize the abundance and diversity of animal species of special concern 9. Minimize the loss of native grassland within each park 10. Minimize the abundance of exotic plants in the park landscape 11. Maximize riparian area and wetland integrity Public Outreach 12. Maximize the number of healthy, wild bison that are visible to the public 13. Maximize the safety of visitors 14. Maximize public understanding of the past, present, and future of bison and Native Americans in the Great Plains The terms “minimize” and “maximize” in these objectives describe the desired direction for each individual objective. Finding the right balance among these objectives and any others identified in further work is one of the central challenges in developing the Strategy. To that end, this report also demonstrates and describes potential methods for evaluating how well alternative strategies would achieve each of the fundamental objectives.

Natural Resource Report↗

Landowner perceptions of three types of boating in the Saranac Lakes area of New York State׳s Adirondack Park

In order for natural resource managers to better understand conflicting landowner perspectives related to non-motorized, motorized, and personal watercraft use, this study examines the demographic and experiential characteristics, values, attitudes, and beliefs of landowners in the Saranac Lakes area of the Adirondack Park in New York State. A mixed-methods approach, composed of 20 in-depth interviews with land managers and a mail survey of 1000 landowners, was used. Three path analyses were completed, one for each type of boat use. Results indicate that resource-related values influence beliefs and attitudes related to boat use, supporting the cognitive hierarchy model of human behavior (Fulton, D. C., Manfredo, M. J., & Lipscomb, J. (1996). Wildlife value orientations: a conceptual and measurement approach. Human Dimensions of Wildlife , 1 , 24–47). In addition, length of residence in the area, past participation in non-motorized and motorized boating, age, and education were found to influence attitudes towards certain types of boating. The results of this study can be used by natural resource managers to identify management strategies that better address the values and recreational interests of landowners.

New York↗

Tower counts

Counting towers provide an accurate, low-cost, low-maintenance, low-technology, and easily mobilized escapement estimation program compared to other methods (e.g., weirs, hydroacoustics, mark-recapture, and aerial surveys) (Thompson 1962; Siebel 1967; Cousens et al. 1982; Symons and Waldichuk 1984; Anderson 2000; Alaska Department of Fish and Game 2003). Counting tower data has been found to be consistent with that of digital video counts (Edwards 2005). Counting towers do not interfere with natural fish migration patterns, nor are fish handled or stressed; however, their use is generally limited to clear rivers that meet specific site selection criteria. The data provided by counting tower sampling allow fishery managers to determine reproductive population size, estimate total return (escapement + catch) and its uncertainty, evaluate population productivity and trends, set harvest rates, determine spawning escapement goals, and forecast future returns (Alaska Department of Fish and Game 1974-2000 and 1975-2004). The number of spawning fish is determined by subtracting subsistence, sport-caught fish, and prespawn mortality from the total estimated escapement. The methods outlined in this protocol for tower counts can be used to provide reasonable estimates ( plus or minus 6%-10%) of reproductive salmon population size and run timing in clear rivers.

Book chapter↗

'Natural background' soil water repellency in conifer forests of the north-western USA: Its prediction and relationship to wildfire occurrence

Soils under a wide range of vegetation types exhibit water repellency following the passage of a fire. This is viewed by many as one of the main causes for accelerated post-fire runoff and soil erosion and it has often been assumed that strong soil water repellency present after wildfire is fire-induced. However, high levels of repellency have also been reported under vegetation types not affected by fire, and the question arises to what degree the water repellency observed at burnt sites actually results from fire. This study aimed at determining 'natural background' water repellency in common coniferous forest types in the north-western USA. Mature or semi-mature coniferous forest sites (n = 81), which showed no evidence of recent fires and had at least some needle cast cover, were sampled across six states. After careful removal of litter and duff at each site, soil water repellency was examined in situ at the mineral soil surface using the Water Drop Penetration Time (WDPT) method for three sub-sites, followed by collecting near-surface mineral soil layer samples (0-3 cm depth). Following air-drying, samples were further analyzed for repellency using WDPT and contact angle (?? sl ) measurements. Amongst other variables examined were dominant tree type, ground vegetation, litter and duff layer depth, slope angle and aspect, elevation, geology, and soil texture, organic carbon content and pH. 'Natural background' water repellency (WDPT > 5 s) was detected in situ and on air-dry samples at 75% of all sites examined irrespective of dominant tree species (Pinus ponderosa, Pinus contorta, Picea engelmanii and Pseudotsuga menziesii). These findings demonstrate that the soil water repellency commonly observed in these forest types following burning is not necessarily the result of recent fire but can instead be a natural characteristic. The notion of a low background water repellency being typical for long-unburnt conifer forest soils of the north-western USA is therefore incorrect. It follows that, where pre-fire water repellency levels are not known or highly variable, post-fire soil water repellency conditions are an unreliable indicator in classifying soil burn severity. The terrain and soil variables examined showed, overall, no convincing relationship with the repellency levels observed (R 2 < 0.15) except that repellency was limited in soils (i) developed over meta-sedimentary lithology and (ii) with clay contents >4%. This suggests that water repellency levels cannot be predicted with confidence from common terrain or soil variables. ?? 2009 Elsevier B.V.

Journal of Hydrology↗

Choosing indicators of natural resource condition: A case study in Arches National Park, Utah, USA

Heavy visitor use in many areas of the world have necessitated development of ways to assess visitation impacts. Arches National Park recently completed a Visitor Experience and Resource Protection (VERP) plan. Integral to this plan was developing a method to identify biological indicators that would both measure visitor impacts and response to management actions. The process used in Arches for indicator selection is outlined here as a model applicable to many areas facing similar challenges. The steps were: (1) Vegetation types most used by visitors were identified. Impacted and unimpacted areas in these types were sampled, comparing vegetation and soil factors. (2) Variables found to differ significantly between compared sites were used as potential indicators. (3) Site-specific criteria for indicators were developed, and potential indicators evaluated using these criteria. (4) Chosen indicators were further researched for ecological relevancy. (5) Final indicators were chosen, field tested, and monitoring sites designated. In Arches, indicators were chosen for monitoring annually (soil crust index, soil compaction, number of used social trails and soil aggregate stability) and every five years (vegetation cover and frequency; ground cover; soil chemistry; and plant tissue chemistry).

Environmental Management↗

Potential freshening impacts on fines migration and pore-throat clogging during gas hydrate production: 2-D micromodel study with Diatomaceous UBGH2 sediments

The methane gas hydrate stored in natural sediments is considered a potential gas resource. Countries such as China, India, Japan, and Korea are interested in commercializing this resource, and offshore field pilot tests for gas production have been conducted using depressurization methods to destabilize gas hydrate and facilitate the migration of methane to the production well. However, fine-grained sediments (fines), which are present even in coarse-grained, gas hydrate-bearing sediments, can be resuspended in the production fluid, subsequently clogging pore throats in the formation and reducing the overall production efficiency. We conducted laboratory tests to evaluate the suspension and clogging potential of fines collected from the Ulleung Basin, East Sea, Korea during the 2010 Ulleung Basin Gas Hydrate Expedition 2 (UBGH2). Experimental results reveal that diatoms are prevalent in the sediment and largely control the suspension and clogging behavior. Fluid flow experiments in 2D micromodels show clogging occurs even when injecting the minimum sediment concentration (0.1wt% in the fluid) through micromodels with pore-throat widths at the high end of the anticipated range for UBGH2 gas hydrate-bearing sands (100µm). Mobile gas/fluid interfaces forming during gas hydrate dissociation accentuate clogging by concentrating and mobilizing fines. Sedimentation tests show pore-water freshening during dissociation is not anticipated to change the potential for diatoms to become entrained in the pore water flow, even for the observed gas hydrate saturations of ~80%. Muscovite and illite are also significant components of the tested sediment, however, and pore-water freshening increases their potential for resuspension and clogging. Overall, the resuspension and clogging potential of these fine sediments should increase as gas hydrate dissociation progresses in the thin, gas hydrate-bearing sands investigated in the Ulleung Basin.

Marine and Petroleum Geology↗

Application of the modified Einstein procedure for computation of total sediment load

A method that enables good estimates to be made of total sediment load has been tested with data from several western streams. The method, which uses both theoretical and empirical formulas, combines a modification of Einstein's procedure for computing bed‐material load and the usually available data from suspended‐sediment measurements. Basic data, including data from large natural and artificial turbulent flumes, and the results of computations are given.

Eos, Transactions, American Geophysical Union↗

Paleoecology and ecosystem restoration: Case studies from Chesapeake Bay and the Florida Everglades

Climate extremes that cause droughts, floods, or large temperature fluctuations can complicate ecosystem restoration efforts focused on local and regional human disturbance. Restoration targets are often based primarily on monitoring data and modeling simulations, which provide information on species' short-term response to disturbance and environmental variables. Consequently, the targets may be unsustainable under the spectrum of natural variability inherent in the system or under future climate change. Increasingly, ecologists and restoration planners recognize the value of the long temporal perspective provided by paleoecological data. Advances in paleoclimatology, including better climate proxy methods and temporal resolution, contribute to our understanding of ecosystem response to anthropogenic and climatic forcing at all time scales. We highlight paleoecological research in the Chesapeake Bay and the Florida Everglades and summarize the resulting contributions to restoration planning. Integration of paleoecological, historic, monitoring, and modeling efforts will lead to the development of sustainable, adaptive management strategies for ecosystem restoration.

Delaware, Florida, Maryland, New York, Pennsylvani↗

Groundwater-quality and quality-control data for two monitoring wells near Pavillion, Wyoming, April and May 2012

In June 2010, the U.S. Environmental Protection Agency installed two deep monitoring wells (MW01 and MW02) near Pavillion, Wyoming, to study groundwater quality. During April and May 2012, the U.S Geological Survey, in cooperation with the Wyoming Department of Environmental Quality, collected groundwater-quality data and quality-control data from monitoring well MW01 and, following well redevelopment, quality-control data for monitoring well MW02. Two groundwater-quality samples were collected from well MW01&mdash;one sample was collected after purging about 1.5 borehole volumes, and a second sample was collected after purging 3 borehole volumes. Both samples were collected and processed using methods designed to minimize atmospheric contamination or changes to water chemistry. Groundwater-quality samples were analyzed for field water-quality properties (water temperature, pH, specific conductance, dissolved oxygen, oxidation potential); inorganic constituents including naturally occurring radioactive compounds (radon, radium-226 and radium-228); organic constituents; dissolved gasses; stable isotopes of methane, water, and dissolved inorganic carbon; and environmental tracers (carbon-14, chlorofluorocarbons, sulfur hexafluoride, tritium, helium, neon, argon, krypton, xenon, and the ratio of helium-3 to helium-4). Quality-control sample results associated with well MW01 were evaluated to determine the extent to which environmental sample analytical results were affected by bias and to evaluate the variability inherent to sample collection and laboratory analyses. Field documentation, environmental data, and quality-control data for activities that occurred at the two monitoring wells during April and May 2012 are presented.

Wyoming↗

Summary of results from a trip February 6-March 5, 1966, to B'ir Idimah, Jabal Ashirah, and As Sarat Mountains, Saudi Arabia

The geologic setting of the pyrite replacement deposit at Wadi Wassat was mapped in February 1966. From this mapping it is inferred that the pyrite deposits occur along a sub-vertical, north-trending fault in andesite and other rocks at the crest line of an anticline in a roof pendant. The pendant is in a composite pluton formed by a per-alkalic magma series. Diorite and biotite granite are the most common and older members of the series. Pyroxene granite and quartz porphyry are less common younger rocks in the series. Extrusive equivalents of these plutonic rocks form dikes in the area. The pyrite is interpreted to have been deposited from hydrothermal solutions after diorite and biotite granite were consolidated and while pyroxene granite was being emplaced. Structures controlling the deposition of the pyrite are regional. Exploration at 1:2,500 scale by geologic, geochemical, and electro-magnetic methods are recommended. Diamond drilling should accompany the other exploration. Chemical analyses of 22 specimens of Precambrian marble from the Asir quadrangle shows that seven deposits have a composition within the range of compositions of natural cement rocks used for Roman cement and quick-setting cement. None of the samples is rich enough in CaO for use as a raw material for Portland cement, and most samples of the marble have too much MgO for Portland cement. Analyses of the major elements in 71 samples of lateritic material from the As Sarat mountains show that none of the laterite can be used as an ore for iron owing to too little iron and too much alumina, silica, and sulfur. One sample has the alumina-silica ratio of gibbsite or boehmite. One sample has alumina and sulfur in percentages suggesting the presence of alunite, and several other samples probably contain alunite. Because alunite is potash rich and might be used as a raw material for potash fertilizer, it is recommended that an airborne radiometric survey be made of tine As Sarat mountains to locate potassium-rich parts of the laterite.

Open-File Report↗

Methods for estimating tributary streamflow in the Chattahoochee River basin between Buford Dam and Franklin, Georgia

Simple and reliable methods for estimating hourly streamflow are needed for the calibration and verification of a Chattahoochee River basin model between Buford Dam and Franklin, Ga. The river basin model is being developed by Georgia Department of Natural Resources, Environmental Protection Division, as part of their Chattahoochee River Modeling Project. Concurrent streamflow data collected at 19 continuous-record, and 31 partial-record streamflow stations, were used in ordinary least-squares linear regression analyses to define estimating equations, and in verifying drainage-area prorations. The resulting regression or drainage-area ratio estimating equations were used to compute hourly streamflow at the partial-record stations. The coefficients of determination (r-squared values) for the regression estimating equations ranged from 0.90 to 0.99. Observed and estimated hourly and daily streamflow data were computed for May 1, 1995, through October 31, 1995. Comparisons of observed and estimated daily streamflow data for 12 continuous-record tributary stations, that had available streamflow data for all or part of the period from May 1, 1995, to October 31, 1995, indicate that the mean error of estimate for the daily streamflow was about 25 percent.

Georgia↗

Hypothetical modeling of redox conditions within a complex ground-water flow field in a glacial setting

This report describes a modeling approach for studying how redox conditions evolve under the influence of a complex ground-water flow field. The distribution of redox conditions within a flow system is of interest because of the intrinsic susceptibility of an aquifer to redox-sensitive, naturally occurring contaminants - such as arsenic - as well as anthropogenic contaminants - such as chlorinated solvents. The MODFLOW-MT3D-RT3D suite of code was applied to a glacial valley-fill aquifer to demonstrate a method for testing the interaction of flow patterns, sources of reactive organic carbon, and availability of electron acceptors in controlling redox conditions. Modeling results show how three hypothetical distributions of organic carbon influence the development of redox conditions in a water-supply aquifer. The distribution of strongly reduced water depends on the balance between the rate of redox reactions and the capability of different parts of the flow system to transmit oxygenated water. The method can take account of changes in the flow system induced by pumping that result in a new distribution of reduced water.

Scientific Investigations Report↗

Estimates of evapotranspiration from the Ruby Lake National Wildlife Refuge area, Ruby Valley, northeastern Nevada, May 1999–October 2000

The Ruby Lake National Wildlife Refuge in Ruby Valley, Nevada, contains the largest area of perennial wetlands in northeastern Nevada and provides habitat to a large number of migratory and nesting waterfowl. The long-term preservation of the refuge depends on the availability of sufficient water to maintain optimal habitat conditions. In the Ruby Valley water budget, evapotranspiration (ET) from the refuge is one of the largest components of natural outflow. To help determine the amount of inflow needed to maintain wetland habitat, estimates of ET for May 1999 through October 2000 were made at major habitats throughout the refuge. The Bowen-ratio method was used to estimate daily ET at four sites: over open water, in a moderate-to-dense cover of bulrush marsh, in a moderate cover of mixed phreatophytic shrubs, and in a desert-shrub upland. The eddy-correlation method was used to estimate daily ET for periods of 2 to 12 weeks at a meadow site and at four sites in a sparse-to-moderate cover of phreatophytic shrubs. Daily ET rates ranged from less than 0.010 inch per day at all of the sites to a maximum of 0.464 inch per day at the open-water site. Average daily ET rates estimated for open water and a bulrush marsh were about four to five times greater than in areas of mixed phreatophytic shrubs, where the depth to ground water is less than 5 feet. Based on the seasonal distribution of major habitats in the refuge and on winter and summer ET rates, an estimated total of about 89,000 acre-feet of water was consumed by ET during October 1999-September 2000 (2000 water year). Of this total, about 49,800 acre-feet was consumed by ET in areas of open water and bulrush marsh.

Nevada↗

Development, calibration, and analysis of a hydrologic and water-quality model of the Delaware Inland Bays watershed

Excessive nutrients and sediment are among the most significant environmental stressors in the Delaware Inland Bays (Rehoboth, Indian River, and Little Assawoman Bays). Sources of nutrients, sediment, and other contaminants within the Inland Bays watershed include point-source discharges from industries and wastewater-treatment plants, runoff and infiltration to ground water from agricultural fields and poultry operations, effluent from on-site wastewater disposal systems, and atmospheric deposition. To determine the most effective restoration methods for the Inland Bays, it is necessary to understand the relative distribution and contribution of each of the possible sources of nutrients, sediment, and other contaminants. A cooperative study involving the Delaware Department of Natural Resources and Environmental Control, the Delaware Geological Survey, and the U.S. Geological Survey was initiated in 2000 to develop a hydrologic and water-quality model of the Delaware Inland Bays watershed that can be used as a water-resources planning and management tool. The model code Hydrological Simulation Program - FORTRAN (HSPF) was used. The 719-square-kilometer watershed was divided into 45 model segments, and the model was calibrated using streamflow and water-quality data for January 1999 through April 2000 from six U.S. Geological Survey stream-gaging stations within the watershed. Calibration for some parameters was accomplished using PEST, a model-independent parameter estimator. Model parameters were adjusted systematically so that the discrepancies between the simulated values and the corresponding observations were minimized. Modeling results indicate that soil and aquifer permeability, ditching, dominant land-use class, and land-use practices affect the amount of runoff, the mechanism or flow path (surface flow, interflow, or base flow), and the loads of sediment and nutrients. In general, the edge-of-stream total suspended solids yields in the Inland Bays watershed are low in comparison to yields reported for the Eastern Shore from the Chesapeake Bay watershed model. The flatness of the terrain and the low annual surface runoff are important factors in determining the amount of detached sediment from the land that is delivered to streams. The highest total suspended solids yields were found in the southern part of the watershed, associated with high total streamflow and a high surface runoff component, and related to soil and aquifer permeability and land use. Nutrient yields from watershed model segments in the southern part of the Inland Bays watershed were the highest of all calibrated segments, due to high runoff and the substantial amount of available organic fertilizer (animal waste), which results in over-application of organic fertilizer to crops. Time series of simulated hourly total nitrogen concentrations and observed instantaneous values indicate a seasonal pattern, with the lowest values occurring during the summer and the highest during the winter months. Total phosphorus and total suspended solids concentrations are somewhat less seasonal. During storm events, total nitrogen concentrations tend to be diluted and total phosphorus concentrations tend to rise sharply. Nitrogen is transported mainly in the aqueous phase and primarily through ground water, whereas phosphorus is strongly associated with sediment, which washes off during precipitation events.

Water-Resources Investigations Report↗

Users guide for distributed routing rainfall-runoff model

A computer program of a watershed model for routing urban flood discharges through a branched system of pipes or natural channels using rainfall as input has been developed and documented. The model combines soil-moisture-accounting and rainfall-excess components developed by Dawdy and others (1972) with the kinematic-wave routing method presented by Leclerc and Schaake (1973). (Woodard-USGS)

Water-Resources Investigations Report↗

Evaluation of methods for estimating ground-water withdrawals in western Kansas

During 1978, methods of estimating ground-water withdrawals in western Kansas were examined and evaluated, using both existing data from the files of the U.S. Geological Survey and newly collected data. Values for annual ground-water withdrawals reported to the Division of Water Resources, Kansas State Board of Agriculture, by water users probably contain substantial errors because most individual users do not possess the means to measure or accurately estimate the discharge rates of their wells. Such reported values are estimated to average 10 to 15 percent higher than the actual discharge rate. Values obtained from discharge-totaling meters are reasonably accurate, but few wells are equipped with these meters, and the cost of equipping all wells with meters may be prohibitive. Measured rates of power consumption can give good estimates of total withdrawal from wells where the power consumption is measured. However, power-consumption values cannot be extrapolated reliably from one well to another. Three techniques are regarded as promising for estimating areal ground-water withdrawals from readily collected data: Examination of a small sample of withdrawal values from metered wells indicates that the statistical approach used by Luckey (1972) may be applied to western Kansas to estimate total withdrawal with acceptable accuracy in a large area from a statistical sample of measured values. Measured values of irrigation application at a small number of selected wells might be used to compute total withdrawal for irrigation by crop type and precipitation zone. Evaluation of reported values of irrigation-water application for selected crops in zones of generally similar precipitation showed that, although the reported values are judged to be erroneously high, the reported values were consistent with each other and with average precipitation. Power-consumption coefficients may be used to calculate an average coefficient for an area. The method described by Luckey (1972) was used to calculate the number of power-consumption coefficients that would have to be determined to estimate the mean power consumption of wells pumped by electric or natural-gas engines. The results indicate that as few as 100 values would produce results accurate to within 10 percent of the true average at the 95-percent confidence level. Thus, power coefficients for a particular type of irrigation system in any given area can be used even though values of power coefficients have little transfer value from well to well. Efforts by the Instrument Development Laboratofy of the U.S. Geological Survey to design improved instruments for measuring ground-water withdrawals have produced two promising results: An electronic running-time meter (Running-time Sentry) that was tested during 1978 in western Kansas and Florida appears to give accurate values of total pumping time. Large-scale testing of this prototype running-time meter is planned for 1979. A low-cost discharge-totaling meter (REELTOT), based on the concept of sensing the velocity head in a pipe with differential-pressure transducers permanently installed in the pipe, is nearly complete. Early prototypes of this instrument may be tested in western Kansas during 1979. For the remainder of this study, the three techniques for estimating areal ground-water withdrawals described above will be tested on a larger scale in Groundwater Management District No. 1, an area of about 1,800 square miles in west-central Kansas. About 150 randomly selected wells will be equipped with Running-time Sentry units and monitored for total withdrawal, instantaneous discharge, and power consumption. A few wells will be equipped with prototype discharge-totaling meters. The performance of the Sentry units and discharge-totaling meters will be evaluated. Areal estimates of withdrawal from measured withdrawal values, from average power-consumption coefficients, and from irrigation application by crop will be calculated and compared with each other and with reported values of withdrawal.

Kansas↗

The LANDFIRE Refresh strategy: updating the national dataset

The LANDFIRE Program provides comprehensive vegetation and fuel datasets for the entire United States. As with many large-scale ecological datasets, vegetation and landscape conditions must be updated periodically to account for disturbances, growth, and natural succession. The LANDFIRE Refresh effort was the first attempt to consistently update these products nationwide. It incorporated a combination of specific systematic improvements to the original LANDFIRE National data, remote sensing based disturbance detection methods, field collected disturbance information, vegetation growth and succession modeling, and vegetation transition processes. This resulted in the creation of two complete datasets for all 50 states: LANDFIRE Refresh 2001, which includes the systematic improvements, and LANDFIRE Refresh 2008, which includes the disturbance and succession updates to the vegetation and fuel data. The new datasets are comparable for studying landscape changes in vegetation type and structure over a decadal period, and provide the most recent characterization of fuel conditions across the country. The applicability of the new layers is discussed and the effects of using the new fuel datasets are demonstrated through a fire behavior modeling exercise using the 2011 Wallow Fire in eastern Arizona as an example.

Fire Ecology↗

Adaptive fine-tuning for transferring a U-net hydrography extraction model using K-means

The United States Geological Survey (USGS) coordinates the collection of hydrographic features derived from remotely sensed interferometric synthetic aperture radar (IfSAR) elevation and intensity data in Alaska. Hydrographic features are cartographic representations of surface water features such as stream, rivers, lakes, ponds, canals, etc. Collection and validation procedures involve complex automated and manual techniques that furnish snapshots of hydrographic vector data that exist during the IfSAR surveys. The dynamic nature of fluvial conditions warrants monitoring and updating hydrographic data, but extraction procedures for updates can be cost prohibitive. This paper overviews progress on automated workflows to extract hydrography from IfSAR data using deep learning methods trained and tested with USGS collected hydrography data. This research tests transfer learning methods on a well-performing U-net model trained on a 4600-square kilometer (sq km) base model area in northcentral Alaska. The base model is transferred and fine-tuned to regions in the target domain covering roughly 127,000 sq km. The target domain is subdivided into areas with similar hydrogeomorphic conditions using principal components and k-means clustering, and the base model is adaptively fine-tuned to each hydrogeomorphic class by selecting training watersheds from each cluster within the target domain. Results are compared with transfer learning that is fine-tuned with a random sample of watersheds in the target domain.

Conference Paper↗