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Habitat Suitability Index Models: Ruffed grouse

A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the ruffed grouse (Bonasa umbellus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

FWS/OBS

Habitat Suitability Index Models: Belted kingfisher

A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the belted kingfisher (Ceryle alcyon). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

FWS/OBS

Habitat Suitability Index Models: Red-winged blackbird

A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the red-winged blackbird (Agelaius phoeniceus L.). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

FWS/OBS

Climate change vulnerability assessment for the California coastal national monument—Trinidad and Point Arena-Stornetta units

Executive Summary The California Coastal National Monument protects islets, reefs, and rock outcropping habitats in six onshore units, including the Trinidad and Point Arena-Stornetta Units. The California Coastal National Monument provides crucial habitat for resident and migratory species of seabirds, marine mammals, and invertebrates, which includes several federally listed threatened and endangered species. Also, the California Coastal National Monument encompasses important tribal, cultural, and historical sites along the coastline of California. We used three approaches to assess the climate change vulnerability of the Trinidad and Point Arena-Stornetta Units: (1) a qualitative approach using peer-reviewed literature and previous work done in the Climate Change Vulnerability Assessment for the North-central California Coast and Ocean (Hutto and others, 2015), (2) interactive workshops with local stakeholders to identify specific resources, and (3) spatial analysis to estimate sea-level rise vulnerability for the rocky shoreline and key resources within the units. Information from stakeholder workshops held (in 2017) in the cities of Point Arena and Trinidad identified climate change impacts as an important management concern for the resilience, health, and ecosystem services of the California Coastal National Monument units. Impacts that were identified included sea-level rise, changes in precipitation and fog, warming oceans, and loss of species (birds, fisheries, marine mammals). Boat surveys were done for each unit to estimate the number of rocky features and the biota using the rocks. At the Trinidad Unit, 138 rocks were surveyed and 17 different wildlife species were observed, whereas at the Point Arena-Stornetta Unit, 40 rocks were surveyed and 10 different wildlife species were observed. Individual rocky features surveyed within the units were then ranked on sea-level rise exposure and vulnerability scales with 1 being the least vulnerable/exposed and 5 the most. Forty-nine and fifty-eight percent of surveyed rocks had a sea-level rise exposure ranking of 4 or 5 (high) for the Trinidad Unit and Point Arena-Stornetta Units respectively. Forty-eight percent of offshore rocks had a sea-level rise vulnerability score of 3 or greater (high) for the Trinidad Unit, and forty-three percent of rocks had a vulnerability score of 3 or greater for the Point Arena-Stornetta Unit. When examining guild use of vulnerable rocks (vulnerability score greater than 3), at the Trinidad Unit alcid species (here defined as common murres and pigeon guillemots) were observed on only 28 percent of vulnerable rocks, shorebirds on 30 percent, sea lions on 40 percent, gulls on 43 percent, seabirds on 58 percent, and mammals on 75 percent, whereas at the Point Arena-Stornetta Unit alcid species were observed on 0 percent of vulnerable rocks, gulls on 33 percent, seabirds on 57 percent, and mammals on 50 percent. Sea-level rise has the potential to submerge small low-relief offshore rocks and make them uninhabitable for birds and marine mammals but could provide more intertidal and subtidal rocky habitats. We found that nearly half of the offshore rocks at both sites are vulnerable and have the potential to realize this outcome; however, the larger and tall-relief rocks at these sites are less vulnerable to sea-level rise and are expected to continue to provide habitat for avian species.

California

New ecological knowledge and practices for society and sustainability

As attributes of the Earth's ecosystems shift in the face of human impact and sustainability of ecosystem services becomes less certain, one important tool at the disposal of the scientific community and other groups is a blueprint for understanding, evaluating, and communicating the value of ecological services. The blueprint presented here is based on (1) an examination of the ecological and societal trade-offs accompanying any given action, (2) revised methods of communication, and (3) coordination of actions at many different scales. The Mexican National Commission for the Knowledge and Use of Biodiversity (CONABIO) is a good example of a demand-driven “bridging institution” between academia, government, and civil society, and it works to collect and convert scientific information into information for policy, management, and conservation. Intergovernmental organizations like the United Nations Educational, Scientific and Cultural Organization (UNESCO) are well placed to facilitate such coordination at the international level, through their work with member states. Through collaboration with the constituencies of such organizations as the Ecological Society of America, the blueprint described below has the potential to become an important tool for assessing and managing threats to ecosystem services that are essential to life.

Frontiers in Ecology and the Environment

Hydrographic and benthic mapping—St. Croix National Scenic Riverway—Osceola landing

High-resolution topographic and bathymetric mapping can assist in the analysis of river habitat. The National Park Service has been planning to relocate a boat ramp along the St. Croix River in Minnesota, across the river from the town of Osceola, Wisconsin, to improve visitor safety, improve operations for commercial use, enhance the overall visitor experience, and eliminate deferred maintenance at the landing. This landing grants access to the St. Croix River, which is a part of the National Park Service St. Croix National Scenic Riverway. Hydrographic and topographic surveys were needed to determine where the new location should be. The objective for these surveys was to provide baseline information in order to assess the direct effects of the landing relocation on physical habitat in areas adjacent to Osceola, Wisconsin. The study area for these surveys was about 18.5 hectares and located directly off the existing landing. Although the existing boat launch is referred to as the Osceola landing, it is located on the Minnesota side of the river and is the busiest National Park Service landing on the St. Croix River (National Park Service St. Croix National Scenic Riverway, 2020). This report documents methods and results of aquatic benthic mapping in a small area of the St. Croix River. The hydroacoustic and topographic surveys were collected from October 16–17, 2019. The hydrographic surveys consisted of multibeam and sidescan sound navigation and ranging (sonars). The topographic shoreline survey consisted of light detection and ranging (lidar) captured by boat adjacent to riverbanks. Additionally, an acoustic Doppler current profiler was used to measure flow velocities. The water level was higher than normal, and therefore had faster flow during the hydroacoustic surveys. Multibeam, lidar, and sidescan surveys occurred the first day, and the velocity mapping and ground truthing was conducted the second day. Multibeam and lidar provided derivative datasets that included bathymetry and a topobathy with a spatial resolution of 1 foot. From these data, additional data could be measured including slope and terrain ruggedness. Sidescan (acoustic reflectance measures) provided imagery that was used to help with interpretation of the river bottom. Outcomes from these combined datasets were substrate and bedform maps. Much of the area was covered in sand ripples or small dunes. A small area running adjacent to the deeper valley or cut down the river consisted of harder substrates, such as cobble and gravel. Large woody debris piles were found throughout the study area. Multiple stationary moving-bed tests were completed, and no corrections were recommended for the conditions occurring during survey. Mussel presence was noted in some of the underwater videos. The physical parameters of depth, flow, bedforms, and substrate derived from the datasets provided baseline measures for a benthic habitat map. Further analysis of benthic habitat might be possible with additional biological and chemical data.

Wisconsin

A review of coastal management approaches to support the integration of ecological and human community planning for climate change

The resilience of socio-ecological systems to sea level rise, storms and flooding can be enhanced when coastal habitats are used as natural infrastructure. Grey infrastructure has long been used for coastal flood protection but can lead to unintended negative impacts. Natural infrastructure often provides similar services as well as added benefits that support short- and long-term biological, cultural, social, and economic goals. While natural infrastructure is becoming more widespread in practice, it often represents a relatively small fraction within portfolios of coastal risk-reducing strategies compared to more traditional grey infrastructure. This study provides a comprehensive review of how natural infrastructure is being used along the United States Atlantic, Gulf of Mexico, and Caribbean coasts related to four habitats – tidal marshes, beaches and barrier islands, mangroves, and biogenic reefs. We compare information on the benefits, opportunities and challenges of implementing natural, grey and hybrid infrastructure in the coastal zone. In addition, we present a suite of actions to increase information and reduce uncertainty so that coastal mangers and planners are aware of the full suite of options for restoration, conservation and planning that maximize ecosystem services over short- and long-term planning horizons.

Journal of Coastal Conservation

Platte River Forum for the Future: workshop model documentation

The Platte River Forum for the Future (PRFF) is an effort by the Nebraska Natural Resources Commission (NNRC) to bring together representatives of interests and agencies concerned with management of the Platte River and, assisted by various computer technologies, to reach some degree of agreement on the “best uses” of the remaining waters of the Platte. Simulation modeling is being used in this effort as a focal point for developing a common understanding of the behavior of the Platte River system, synthesizing existing information, identifying additional needed information, and analyzing the potential consequences of various management alternatives. The NNRC initiated the project in August 1982 by convening a workshop for interested parties in Grand Island, Nebraska. This workshop was devoted to construction of a preliminary simulation model describing the Platte River system. A group of facilitators/modelers from the U.S. Fish and Wildlife Service (FWS) assisted participants in translating their understanding of the Platte River into the framework of the model. In October 1982, FWS personnel began a process of training several people from Nebraska in the use of the model. At that time, minor revisions and corrections were made in the model and various development scenarios were prepared for discussion with participants at a second workshop, which was held in early November 1982. The purpose of this report is to document the status of the PRFF simulation model as of the end of the November 1982 meeting. We emphasize that the intent is not to describe a final product. Except for minor revisions and correction of obvious errors, the model described herein is that which existed at the end of the August workshop. The model contains the foundation for a comprehensive aid to decisionmakers, but at this time it is preliminary in nature, needing refinement and verification before it can be truly useful in analyzing management alternatives. The purpose of this report is to provide a solid foundation for that important future work. The report is divided into three basic parts. The first is a brief overview of the various components of the model and how they fit together. It is intended for those who are not particularly interested in the details of model formulation. The second is a detailed discussion of the logic, assumptions, equations, and data used in constructing the model. This detailed description is also referenced to specific sections of the third part, which is a set of appendices containing listings of the computer code as it presently exists.

Nebraska

Geologic map of the Maumee quadrangle, Searcy and Marion Counties, Arkansas

This map summarizes the geology of the Maumee 7.5-minute quadrangle in northern Arkansas. The map area is in the Ozark plateaus region on the southern flank of the Ozark dome. The Springfield Plateau, composed of Mississippian cherty limestone, overlies the Salem Plateau, composed of Ordovician carbonate and clastic rocks, with areas of Silurian rocks in between. Erosion related to the Buffalo River and its tributaries, Tomahawk, Water, and Dry Creeks, has exposed a 1,200-ft-thick section of Mississippian, Silurian, and Ordovician rocks mildly deformed by faults and folds. An approximately 130-mile-long corridor along the Buffalo River forms the Buffalo National River that is administered by the National Park Service. McKnight (1935) mapped the geology of the Maumee quadrangle as part of a larger 1:125,000-scale map focused on understanding the lead and zinc deposits common in the area. Detailed new mapping for this study was compiled using a Geographic Information System (GIS) at 1:24,000 scale. Site location and elevation were obtained by using a Global Positioning Satellite (GPS) receiver in conjunction with a U.S. Geological Survey 7.5-minute topographic map and barometric altimeter. U.S. Geological Survey 10-m digital elevation model data were used to derive a hill-shade-relief map used along with digital orthophotographs to map ledge-forming units between field sites. Bedding attitudes were measured in drainage bottoms and on well-exposed ledges. Bedding measured at less than 2 degree dip is indicated as horizontal. Structure contours constructed for the base of the Boone Formation are constrained by field-determined elevations on both upper and lower formation contacts.

Scientific Investigations Map

Flood-inundation maps for the Patoka River in and near Jasper, southwestern Indiana

Digital flood-inundation maps for a 9.5-mile reach of the Patoka River in and near the city of Jasper, southwestern Indiana (Ind.), from the streamgage near County Road North 175 East, downstream to State Road 162, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science web site at https://water.usgs.gov/osw/flood_inundation/ , depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage Patoka River at Jasper, Ind. (station number 03375500). The Patoka streamgage is located at the upstream end of the 9.5-mile river reach. Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at https://waterdata.usgs.gov/ or the National Weather Service Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/ , although flood forecasts and stages for action and minor, moderate, and major flood stages are not currently (2017) available at this site (JPRI3). Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at the Patoka River at Jasper, Ind., streamgage and the documented high-water marks from the flood of April 30, 2017. The calibrated hydraulic model was then used to compute five water-surface profiles for flood stages referenced to the streamgage datum ranging from 15 feet (ft), or near bankfull, to 19 ft. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging [lidar] data having a 0.98 ft vertical accuracy and 4.9 ft horizontal resolution) to delineate the area flooded at each water level. The availability of these flood-inundation maps, along with real-time stage from the USGS streamgage at the Patoka River at Jasper, Ind., will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for postflood recovery efforts.

Indiana

Differentiating sediment sources using sediment fingerprinting techniques, in the Sprague River Basin, South-Central Oregon

Identifying sources of sediment to streams in the Sprague River Basin, in south-central Oregon, is important for restoration efforts that are focused on reducing sediment erosion and transport. Reducing sediment loads in these streams also contributes to compliance with the total maximum daily load reduction requirements for total phosphorus in this basin. In the Sprague River Basin, phosphorus occurs in surface waters in both dissolved phase and particulate phase, and particulate phosphorus is readily transported in streams on fine-grained suspended sediments, which eventually deposit in Upper Klamath Lake. The lake has seasonal blooms of cyanobacteria that require phosphorus for growth and degrade water-quality conditions, violating State water-quality standards and creating conditions that are stressful to two endangered suckers that reside in the lake. Identifying sources of sediment to the Sprague River could help inform restoration actions by determining the principal locations in the basin contributing fine sediment to the river. The U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, conducted a proof-of-concept study to determine if sediment fingerprinting can differentiate sources of bank erosion by source material, basin, river reach, and soil horizon. The sediment fingerprinting approach uses properties of streambank and streambed sediment to differentiate between multiple sediment sources by determining a composite signature, or fingerprint. The composite fingerprint is established by combining fingerprint properties from laboratory results of elemental analysis, stable isotopes, and total carbon and nitrogen. The methods for differentiating sediment samples for this study include grouping bank and bed samples by basin, river reach, and soil horizon, and using non-parametric statistics to determine which fingerprint properties could be used to differentiate the sample groups. Results indicate that fingerprint properties differentiated source material, river reach, and basin, and were more successful at differentiating samples grouped by geographic location (basin and reach) compared to source material. Source material (banks, bed, levees) were differentiated with three fingerprint properties—Antimony (Sb), copper (Cu), and manganese (Mn). The basin category (South Fork and main-stem Sprague River) differentiated the South Fork and main stem with stable nitrogen isotopes (δ 15 N), aluminum (Al), silicon (Si), and vanadium (V). Specific river reaches within the study area were differentiated with 11 different fingerprint properties. These results can be used for apportionment studies using suspended sediment samples and mixing models to determine sediment source contributions within the basin.

Oregon

Oil and gas development in southwestern Wyoming— Energy data and services for the Wyoming Landscape Conservation Initiative (WLCI)

The purpose of this report is to explore current oil and gas energy development in the area encompassing the Wyoming Landscape Conservation Initiative. The Wyoming Landscape Conservation Initiative is a long-term science-based effort to ensure southwestern Wyoming's wildlife and habitat remain viable in areas facing development pressure. Wyoming encompasses some of the highest quality wildlife habitats in the Intermountain West. At the same time, this region is an important source of natural gas. Using Geographic Information System technology, energy data pertinent to the conservation decision-making process have been assembled to show historical oil and gas exploration and production in southwestern Wyoming. In addition to historical data, estimates of undiscovered oil and gas are included from the 2002 U.S. Geological Survey National Assessment of Oil and Gas in the Southwestern Wyoming Province. This report is meant to facilitate the integration of existing data with new knowledge and technologies to analyze energy resources development and to assist in habitat conservation planning. The well and assessment data can be accessed and shared among many different clients including, but not limited to, an online web-service for scientists and resource managers engaged in the Initiative.

Wyoming

Moderate flood level scenarios—Synthetic storm-driven flood-inundation maps for coastal communities in 10 New Jersey counties

The U.S. Geological Survey (USGS), in cooperation with the New Jersey Department of Environmental Protection (NJDEP) and the New Jersey Office of Emergency Management (NJOEM), created digital flood-inundation maps for approximately 1,430 square miles of the New Jersey coast and tidewaters through 10 coastal counties stretching from Cumberland County through Bergen County, New Jersey. The maps depict extent and depth estimates of coastal flooding corresponding to selected tidal elevations recorded by 25 real-time USGS tide gages located within the study area. The flood-inundation maps can be accessed through the USGS Interagency Flood Risk Management (InFRM) Flood Decision Support Toolbox (FDST). Previously published modeled data were utilized from the coupled ADvanced CIRCulation Model (ADCIRC) and Simulating Waves Nearshore (SWAN) model. Simulated tropical storm events were selected based on parameters including landfall location or closest approach location, maximum wind speed, central pressure, and radii of winds. Two storm events were selected per tide gage providing two “scenarios” and accompanying inundation-map libraries for each gage. Flood-inundation maps reflect between 9 to 30 stages (elevations) at each tide gage that correspond to areal extents and depths for ADCIRC-SWAN storm time steps extracted from modeled hydrographs at the gage locations. Water-surface elevations from ADCIRC-SWAN node points extending through each tide gage station extent were used to interpolate a water surface. Combining these surfaces with a geographic information system (GIS) topobathymetric digital elevation model (TBDEM) delineated the area flooded by coastal waters at each tide gage elevation. The availability of these maps to visualize potential inundation for selected water levels along with real-time water level data available online from USGS tide gages, coastal impact statements, and forecasted tide elevations from the National Weather Service (NWS) will provide emergency management personnel and residents with a link between numeric and text warning information and images of estimated inundation extents in their community. User selected display of inundation allows early response activities to NWS forecasted water level elevations or mitigation planning by selecting targeted water levels and planning critical pre-flood activities such as building elevations, early traffic pattern changes because of neighborhood building inundation levels, improved understanding about when major road access is affected, as well as for post-flood recovery efforts. A subsequent analysis of several community metrics including total structures, structure density, percent of buildings inundated, and roads and bridges affected by flooding was used to evaluate moderate flooding impacts among the mapped station extents. Initial comparisons are presented to show the variability of these characteristics within each mapped station extent then extended to evaluate impacts from moderate flooding on these same areas. The analysis used simulated inundation layers at the moderate flood stage to investigate the magnitude of inundation on building structures and major roads among the mapped station extents. Experimental equations were developed to begin testing if a mathematical equation could help identify communities that were disproportionately impacted at moderate flood stage. The community analysis of impacts to moderate flooding based on these inundation scenario maps should provide community leaders and local and state planning officials with tools to better visualize and understand how flooding begins to disrupt and damage building structures and major roads as a surrogate for direct increased risk to human life and property.

New Jersey

A coastal and marine digital library at USGS

The Marine Realms Information Bank (MRIB) is a distributed geolibrary [NRC, 1999] from the U.S. Geological Survey (USGS) and the Woods Hole Oceanographic Institution (WHOI), whose purpose is to classify, integrate, and facilitate access to Earth systems science information about ocean, lake, and coastal environments. Core MRIB services are: (1) the search and display of information holdings by place and subject, and (2) linking of information assets that exist in remote physical locations. The design of the MRIB features a classification system to integrate information from remotely maintained sources. This centralized catalogue organizes information using 12 criteria: locations, geologic time, physiographic features, biota, disciplines, research methods, hot topics, project names, agency names, authors, content type, and file type. For many of these fields, MRIB has developed classification hierarchies.

Eos, Transactions, American Geophysical Union

Results of the Level-1 Water-Quality Inventory at the Pinnacles National Monument, June 2006

To help define baseline water quality of key water resources at Pinnacles National Monument, California, the U.S. Geological Survey collected and analyzed ground water from seven springs sampled during June 2006. During the dry season, seeps and springs are the primary source of water for wildlife in the monument and provide habitat for plants, amphibians, and aquatic life. Water samples were analyzed for dissolved concentrations of major ions, trace elements, nutrients, stable isotopes of hydrogen and oxygen, and tritium. In most cases, the concentrations of measured water-quality constituents in spring samples were lower than California threshold standards for drinking water and Federal threshold standards for drinking water and aquatic life. The concentrations of dissolved arsenic in three springs were above the Federal Maximum Contaminant Level for drinking water (10 g/L). Water-quality information for samples collected from the springs will provide a reference point for comparison of samples collected from future monitoring networks and hydrologic studies in the Pinnacles National Monument, and will help National Park Service managers assess relations between water chemistry, geology, and land use.

Data Series

Flood-inundation maps for the DuPage River from Plainfield to Shorewood, Illinois, 2013

Digital flood-inundation maps for a 15.5-mi reach of the DuPage River from Plainfield to Shorewood, Illinois, were created by the U.S. Geological Survey (USGS) in cooperation with the Will County Stormwater Management Planning Committee. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent of flooding corresponding to selected water levels (gage heights or stages) at the USGS streamgage at DuPage River at Shorewood, Illinois (sta. no. 05540500). Current conditions at the USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?05540500. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages. The NWS-forecasted peak-stage information, also shown on the DuPage River at Shorewood inundation Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was then used to determine nine water-surface profiles for flood stages at 1-ft intervals referenced to the streamgage datum and ranging from NWS Action stage of 6 ft to the historic crest of 14.0 ft. The simulated water-surface profiles were then combined with a Digital Elevation Model (DEM) (derived from Light Detection And Ranging (LiDAR) data) by using a Geographic Information System (GIS) in order to delineate the area flooded at each water level. These maps, along with information on the Internet regarding current gage height from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for postflood recovery efforts.

Illinois

An analytical method for predicting postwildfire peak discharges

An analytical method presented here that predicts postwildfire peak discharge was developed from analysis of paired rainfall and runoff measurements collected from selected burned basins. Data were collected from 19 mountainous basins burned by eight wildfires in different hydroclimatic regimes in the western United States (California, Colorado, Nevada, New Mexico, and South Dakota). Most of the data were collected for the year of the wildfire and for 3 to 4 years after the wildfire. These data provide some estimate of the changes with time of postwildfire peak discharges, which are known to be transient but have received little documentation. The only required inputs for the analytical method are the burned area and a quantitative measure of soil burn severity (change in the normalized burn ratio), which is derived from Landsat reflectance data and is available from either the U.S. Department of Agriculture Forest Service or the U.S. Geological Survey. The method predicts the postwildfire peak discharge per unit burned area for the year of a wildfire, the first year after a wildfire, and the second year after a wildfire. It can be used at three levels of information depending on the data available to the user; each subsequent level requires either more data or more processing of the data. Level 1 requires only the burned area. Level 2 requires the burned area and the basin average value of the change in the normalized burn ratio. Level 3 requires the burned area and the calculation of the hydraulic functional connectivity, which is a variable that incorporates the sequence of soil burn severity along hillslope flow paths within the burned basin. Measurements indicate that the unit peak discharge response increases abruptly when the 30-minute maximum rainfall intensity is greater than about 5 millimeters per hour (0.2 inches per hour). This threshold may relate to a change in runoff generation from saturated-excess to infiltration-excess overland flow. The threshold value was about 7.6 millimeters per hour for the year of the wildfire and the first year after the wildfire, and it was about 11.1 millimeters per hour for the second year after the wildfire.

California;Colorado;Nevada;New Mexico;South Dakota

Quality-assurance results for routine water analyses in U.S. Geological Survey laboratories, water year 1998

The U.S. Geological Survey operates a quality-assurance program based on the analyses of reference samples for two laboratories: the National Water Quality Laboratory and the Quality of Water Service Unit. Reference samples that contain selected inorganic, nutrient, and low-level constituents are prepared and submitted to the laboratory as disguised routine samples. The program goal is to estimate precision and bias for as many analytical methods offered by the participating laboratories as possible. Blind reference samples typically are submitted at a rate of 2 to 5 percent of the annual environmental-sample load for each constituent. The samples are distributed to the laboratories throughout the year. The reference samples are subject to the identical laboratory handling, processing, and analytical procedures as those applied to environmental samples and, therefore, have been used as an independent source to verify bias and precision of laboratory analytical methods and ambient water-quality measurements. The results are stored permanently in the National Water Information System and the Blind Sample Project's data base. During water year 1998, 95 analytical procedures were evaluated at the National Water Quality Laboratory and 63 analytical procedures were evaluated at the Quality of Water Service Unit. An overall evaluation of the inorganic and low-level constituent data for water year 1998 indicated 77 of 78 analytical procedures at the National Water Quality Laboratory met the criteria for precision. Silver (dissolved, inductively coupled plasma-mass spectrometry) was determined to be imprecise. Five of 78 analytical procedures showed bias throughout the range of reference samples: chromium (dissolved, inductively coupled plasma-atomic emission spectrometry), dissolved solids (dissolved, gravimetric), lithium (dissolved, inductively coupled plasma-atomic emission spectrometry), silver (dissolved, inductively coupled plasma-mass spectrometry), and zinc (dissolved, inductively coupled plasma-mass spectrometry). At the National Water Quality Laboratory during water year 1998, lack of precision was indicated for 2 of 17 nutrient procedures: ammonia as nitrogen (dissolved, colorimetric) and orthophosphate as phosphorus (dissolved, colorimetric). Bias was indicated throughout the reference sample range for ammonia as nitrogen (dissolved, colorimetric, low level) and nitrate plus nitrite as nitrogen (dissolved, colorimetric, low level). All analytical procedures tested at the Quality of Water Service Unit during water year 1998 met the criteria for precision. One of the 63 analytical procedures indicated a bias throughout the range of reference samples: aluminum (whole-water recoverable, inductively coupled plasma-atomic emission spectrometry, trace).

Water-Resources Investigations Report