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Practical guide to measuring wetland carbon pools and fluxes

Wetlands cover a small portion of the world, but have disproportionate influence on global carbon (C) sequestration, carbon dioxide and methane emissions, and aquatic C fluxes. However, the underlying biogeochemical processes that affect wetland C pools and fluxes are complex and dynamic, making measurements of wetland C challenging. Over decades of research, many observational, experimental, and analytical approaches have been developed to understand and quantify pools and fluxes of wetland C. Sampling approaches range in their representation of wetland C from short to long timeframes and local to landscape spatial scales. This review summarizes common and cutting-edge methodological approaches for quantifying wetland C pools and fluxes. We first define each of the major C pools and fluxes and provide rationale for their importance to wetland C dynamics. For each approach, we clarify what component of wetland C is measured and its spatial and temporal representativeness and constraints. We describe practical considerations for each approach, such as where and when an approach is typically used, who can conduct the measurements (expertise, training requirements), and how approaches are conducted, including considerations on equipment complexity and costs. Finally, we review key covariates and ancillary measurements that enhance the interpretation of findings and facilitate model development. The protocols that we describe to measure soil, water, vegetation, and gases are also relevant for related disciplines such as ecology. Improved quality and consistency of data collection and reporting across studies will help reduce global uncertainties and develop management strategies to use wetlands as nature-based climate solutions.

Wetlands↗

A multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions

During volcanic eruptions, volcanic ash transport and dispersion models (VATDs) are used to forecast the location and movement of ash clouds over hours to days in order to define hazards to aircraft and to communities downwind. Those models use input parameters, called “eruption source parameters”, such as plume height H , mass eruption rate Ṁ , duration D , and the mass fraction m 63 of erupted debris finer than about 4ϕ or 63 μm, which can remain in the cloud for many hours or days. Observational constraints on the value of such parameters are frequently unavailable in the first minutes or hours after an eruption is detected. Moreover, observed plume height may change during an eruption, requiring rapid assignment of new parameters. This paper reports on a group effort to improve the accuracy of source parameters used by VATDs in the early hours of an eruption. We do so by first compiling a list of eruptions for which these parameters are well constrained, and then using these data to review and update previously studied parameter relationships. We find that the existing scatter in plots of H versus Ṁ yields an uncertainty within the 50% confidence interval of plus or minus a factor of four in eruption rate for a given plume height. This scatter is not clearly attributable to biases in measurement techniques or to well-recognized processes such as elutriation from pyroclastic flows. Sparse data on total grain-size distribution suggest that the mass fraction of fine debris m 63 could vary by nearly two orders of magnitude between small basaltic eruptions (∼ 0.01) and large silicic ones (> 0.5). We classify eleven eruption types; four types each for different sizes of silicic and mafic eruptions; submarine eruptions; “brief” or Vulcanian eruptions; and eruptions that generate co-ignimbrite or co-pyroclastic flow plumes. For each eruption type we assign source parameters. We then assign a characteristic eruption type to each of the world's ∼ 1500 Holocene volcanoes. These eruption types and associated parameters can be used for ash-cloud modeling in the event of an eruption, when no observational constraints on these parameters are available.

Journal of Volcanology and Geothermal Research↗

Site-characteristic and hydrologic data for selected wells and springs on Federal land in Clark County, Nevada

Site-characteristic and hydrologic data for selected wells and springs on U.S. Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service, and U.S. Forest Service land in Clark County, Nevada, were updated in the U.S. Geological Survey’s National Water Information System (NWIS) to facilitate multi-agency research. Data were researched and reviewed, sites were visited, and NWIS data were updated for 231 wells and 198 springs, including 36 wells and 67 springs that were added to NWIS and 44 duplicate sites that were deleted. The site-characteristic and hydrologic data collected, reviewed, edited, and added to NWIS include locations, well water levels, spring discharges, and water chemistry. Site-characteristic and hydrologic data can be accessed from links to the NWIS web interface; data not available through the web interface are presented in appendixes to this report.

Nevada↗

The 3D Elevation Program and energy for the Nation

High-resolution light detection and ranging (lidar) data are used in energy infrastructure siting, design, permitting, construction, and monitoring to promote public safety through the reduction of risks. For example, lidar data are used to identify safe locations for energy infrastructure by analyzing terrain parameters and identifying and evaluating geologic hazards (for example, landslide and fault locations) and their potential public safety effects on the location or design of infrastructure. Increasingly, engineering companies and regulatory agencies are using lidar and other remote sensing techniques as an efficient method to collect accurate, comprehensive data while reducing risks to field personnel. The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) is collecting lidar data nationwide (interferometric synthetic aperture radar [IfSAR] data in Alaska) to support a wide range of applications, including projects related to energy infrastructure construction and safety. Renewable energy resources, resource mining, and oil and gas resources were identified by the National Enhanced Elevation Assessment as business uses requiring three-dimensional (3D) elevation data. Elevation data are critical in assessing potential sites for energy infrastructure, such as pipelines, refineries and other facilities, to mitigate risks from natural hazards. For example, the Federal Energy Regulatory Commission (FERC), an independent agency that regulates the interstate transmission of electricity, natural gas, and oil, uses enhanced elevation data to conduct National Environmental Policy Act (NEPA) compliance assessments. The acquisition of high-resolution lidar data by the USGS 3DEP initiative helps the FERC and NEPA permit applicants by providing accurate and consistent data for hazards analysis. The use of these data accelerates the application and review process and avoids the much higher costs of acquiring elevation data along proposed energy facility locations and pipeline corridors.

Fact Sheet↗

Great Basin Paleontological Bibliography

Introduction This work was conceived as a derivative product for 'The Metallogeny of the Great Basin' project of the Mineral Resources Program of the U.S. Geological Survey. In the course of preparing a fossil database for the Great Basin that could be accessed from the Internet, it was determined that a comprehensive paleontological bibliography must first be compiled, something that had not previously been done. This bibliography includes published papers and abstracts as well as unpublished theses and dissertations on fossils and stratigraphy in Nevada and adjoining portions of California and Utah. This bibliography is broken into first-order headings by geologic age, secondary headings by taxonomic group, followed by ancillary topics of interest to both paleontologists and stratigraphers; paleoecology, stratigraphy, sedimentary petrology, paleogeography, tectonics, and petroleum potential. References were derived from usage of Georef, consultation with numerous paleontologists and geologists working in the Great Basin, and literature currently on hand with the authors. As this is a Web-accessible bibliography, we hope to periodically update it with new citations or older references that we have missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the readers think should be added. As a final note, we gratefully acknowledge the helpful reviews provided by A. Elizabeth J. Crafford (Anchorage, Alaska) and William R. Page (USGS, Denver, Colorado).

Open-File Report↗

Synthesis of climate and ecological science to support grassland management priorities in the North Central Region

Grasslands in the Great Plains are of ecological, economic, and cultural importance in the United States. In response to a need to understand how climate change and variability will impact grassland ecosystems and their management in the 21st century, the U.S. Geological Survey North Central Climate Adaptation Science Center led a synthesis of peer-reviewed climate and ecology literature relevant to grassland management in the North Central Region (including Montana, Wyoming, Colorado, North Dakota, South Dakota, Nebraska, and Kansas). This synthesis was done to begin to address grassland managers’ information needs and identify research gaps. This open-file report summarizes the impacts of climate change and variability on temperature, water availability, wildfire, vegetation, wildlife, large-bodied ruminants, grazing, and land-use change and the implications for grassland management in the North Central region. This open-file report also identifies areas in which further research is needed. U.S. Geological Survey funded this project.

Colorado, Kansas, Montana, Nebraska, North Dakota,↗

A century of studying effusive eruptions in Hawaii

The Hawaiian Volcano Observatory (HVO) was established as a natural laboratory to study volcanic processes. Since the most frequent form of volcanic activity in Hawai‘i is effusive, a major contribution of the past century of research at HVO has been to describe and quantify lava flow emplacement processes. Lava flow research has taken many forms; first and foremost it has been a collection of basic observational data on active lava flows from both Mauna Loa and Kīlauea volcanoes that have occurred over the past 100 years. Both the types and quantities of observational data have changed with changing technology; thus, another important contribution of HVO to lava flow studies has been the application of new observational techniques. Also important has been a long-term effort to measure the physical properties (temperature, viscosity, crystallinity, and so on) of flowing lava. Field measurements of these properties have both motivated laboratory experiments and presaged the results of those experiments, particularly with respect to understanding the rheology of complex fluids. Finally, studies of the dynamics of lava flow emplacement have combined detailed field measurements with theoretical models to build a framework for the interpretation of lava flows in numerous other terrestrial, submarine, and planetary environments. Here, we attempt to review all these aspects of lava flow studies and place them into a coherent framework that we hope will motivate future research.

Hawaii↗

Amphibian responses to wildfire in the western united states: Emerging patterns from short-term studies

The increased frequency and severity of large wildfires in the western United States is an important ecological and management issue with direct relevance to amphibian conservation. Although the knowledge of fire effects on amphibians in the region is still limited relative to most other vertebrate species, we reviewed the current literature to determine if there are evident patterns that might be informative for conservation or management strategies. Of the seven studies that compared pre- and post-wildfire data on a variety of metrics, ranging from amphibian occupancy to body condition, two reported positive responses and five detected negative responses by at least one species. Another seven studies used a retrospective approach to compare effects of wildfire on populations: two studies reported positive effects, three reported negative effects from wildfire, and two reported no effects. All four studies that included plethodontid salamanders reported negative effects on populations or individuals; these effects were greater in forests where fire had been suppressed and in areas that burned with high severity. Species that breed in streams are also vulnerable to post-wildfire changes in habitat, especially in the Southwest. Wildfire is also important for maintaining suitable habitat for diverse amphibian communities, although those results may not be evident immediately after an area burns. We expect that wildfire will extirpate few healthy amphibian populations, but it is still unclear how populations will respond to wildfire in the context of land management (including pre- and post-fire timber harvest) and fragmentation. Wildfire may also increase the risk of decline or extirpation for small, isolated, or stressed (e.g., from drought or disease) populations. Improved understanding of how these effects vary according to changes in fire frequency and severity are critical to form more effective conservation strategies for amphibians in the western United States.

Fire Ecology↗

A manual to identify sources of fluvial sediment

Sediment is an important pollutant of concern that can degrade and alter aquatic habitat. A sediment budget is an accounting of the sources, storage, and export of sediment over a defined spatial and temporal scale. This manual focuses on field approaches to estimate a sediment budget. We also highlight the sediment fingerprinting approach to attribute sediment to different watershed sources. Determining the sources and sinks of sediment is important in developing strategies to reduce sediment loads to water bodies impaired by sediment. Therefore, this manual can be used when developing a sediment TMDL requiring identification of sediment sources. The manual takes the user through the seven necessary steps to construct a sediment budget: Decision-making for watershed scale and time period of interest Familiarization with the watershed by conducting a literature review, compiling background information and maps relevant to study questions, conducting a reconnaissance of the watershed Developing partnerships with landowners and jurisdictions Characterization of watershed geomorphic setting Development of a sediment budget design Data collection Interpretation and construction of the sediment budget Generating products (maps, reports, and presentations) to communicate findings. Sediment budget construction begins with examining the question(s) being asked and whether a sediment budget is necessary to answer these question(s). If undertaking a sediment budget analysis is a viable option, the next step is to define the spatial scale of the watershed and the time scale needed to answer the question(s). Of course, we understand that monetary constraints play a big role in any decision. Early in the sediment budget development process, we suggest getting to know your watershed by conducting a reconnaissance and meeting with local stakeholders. The reconnaissance aids in understanding the geomorphic setting of the watershed and potential sources of sediment. Identifying the potential sediment sources early in the design of the sediment budget will help later in deciding which tools are necessary to monitor erosion and/or deposition at these sources. Tools can range from rapid inventories to estimate the sediment budget or quantifying sediment erosion, deposition, and export through more rigorous field monitoring. In either approach, data are gathered and erosion and deposition calculations are determined and compared to the sediment export with a description of the error uncertainty. Findings are presented to local stakeholders and management officials. Sediment fingerprinting is a technique that apportions the sources of fine-grained sediment in a watershed using tracers or fingerprints. Due to different geologic and anthropogenic histories, the chemical and physical properties of sediment in a watershed may vary and often represent a unique signature (or fingerprint) for each source within the watershed. Fluvial sediment samples (the target sediment) are also collected and exhibit a composite of the source properties that can be apportioned through various statistical techniques. Using an unmixing-model and error analysis, the final apportioned sediment is determined.

Report↗

Captive propagation, introduction, and translocation programs for wildlife vertebrates

Captive propagation, introduction, and translocation (relocation) programs for many animals have been undertaken by federal, state, and private agencies for more than 20 years. These programs help aid the recovery of endangered and threatened species, reestablish lost species, augment declining populations, increase recreational opportunities, reduce nuisance species, and introduce non-native species. Davidson and Nettles (1992) discuss translocation as a component of successful early restorations of game species including wild turkey ( Meleagris gallopavo ) and white-tailed deer ( Odocoileus virginianus ), and recovery of endangered species such as the peregrine falcon (Falco peregrinus). Despite some successes, the total number of translocations that occur yearly is unknown, as is the success and effects of these programs, because there is rarely appreciable monitoring after release (Griffith et al. 1989; Gogan 1990). This report focuses on trends in the use of translocation programs and disease transmission following translocation of wildlife vertebrates other than fish. In the absence of a national data base on wildlife translocations, a search for publications with information on translocations was performed by using Wildlife Review and the U.S. Fish and Wildlife Reference Service CD-ROM data bases for the 20-year period, 1971-91. In addition, personnel from multiple federal, state, and private agencies that conduct propagation and translocation programs were contacted for supplemental information and literature. Increasing numbers of books (Neilsen and Brown 1988), journals (Ullrey 1993), and meetings (Junge 1992; Wolff and Seal 1992) discuss wildlife translocations and many contain information on the effects of translocations on animals and their environment.

Book chapter↗

Aqueous geochemical data from the analysis of stream-water samples collected in June and August 2008—Taylor Mountains 1:250,000- and Dillingham D-4 1:63,360-scale quadrangles, Alaska

We report on the chemical analysis of water samples collected from the Taylor Mountains 1:250,000- and Dillingham D-4 1:63,360-scale quadrangles, Alaska. Reported parameters include pH, conductivity, water temperature, major cation and anion concentrations, and trace-element concentrations. We collected the samples as part of a multiyear U.S. Geological Survey project entitled "Geologic and Mineral Deposit Data for Alaskan Economic Development." Data presented here are from samples collected in June and August 2008. Minimal interpretation accompanies this data release. This is the fourth release of aqueous geochemical data from this project; data from samples collected in 2004, 2005, and 2006 were published previously. The data in this report augment but do not duplicate or supersede the previous data releases. Site selection was based on a regional sampling strategy that focused on first- and second-order drainages. Water sample sites were selected on the basis of landscape parameters that included physiography, wetland extent, lithological changes, and a cursory field review of mineralogy from pan concentrates. Stream water in the study area is dominated by bicarbonate (HCO 3 - ), although in a few samples more than 50 percent of the anionic charge can be attributed to sulfate (SO 4 2- ). The major-cation chemistry of these samples ranges from Ca 2+ -Mg 2+ dominated to a mix of Ca 2+ -Mg 2+ -Na + +K 2+ . In most cases, analysis of duplicate samples showed good agreement for the major cation and major anions with the exception of the duplicate samples at site 08TA565. At site 08TA565, Ca, Mg, Cl, and CaCO 3 exceeded 25 percent and the concentrations of trace elements As, Fe and Mn also exceeded 25 percent in this duplicate pair. Chloride concentration varied by more than 25 percent in 5 of the 11 duplicated samples. Trace-element concentrations in these samples generally were at or near the detection limit for the method used and, except for Co at site 08TA565, generally good agreement was determined between duplicate samples for elements with detectable concentrations. Major-ion concentrations were below detection limits in all field blanks, and the trace-element concentrations also were generally below detection limits; however, Co, Mn, Na, Zn, Cl, and Hg were detected in one or more field blank samples.

Alaska↗

Wetland modeling and information needs at Stillwater National Wildlife Refuge

The marshes in and around Stillwater National Wildlife Refuge (the Refuge) are extremely dynamic; expanding and contracting in size both seasonally, due to runoff and subsequent evapotranspiration, and over longer periods, due to climatic variation. The dynamic nature of these marshes results in a diversity of wetland habitats, which support a variety of migratory birds. To maintain this wetland diversity and control the loss of migratory bird habitat in the Lahontan Valley, the Refuge was established and currently manages a complex of marsh units. However, changes in the hydrology, and changes that will occur as a result of the Fallon Paiute-Shoshone and Truckee-Carson-Pyramid Lake Water Rights Settlement Act (Public Law 101-618, 104 Stat. 3389), greatly affect the Refuge's wetland management capability. In light of these changes, and the legal requirements associated with environmental impact assessments, the Refuge convened a workshop to discuss several aspects of wetland management in the Lahontan Valley. The workshop, described in this report, had three primary objectives: 1. discuss the types and relative proportions of primary wetland habitats that should be provided as described in the settlement act; 2. discuss wetland management models that might be developed to help manage these marshes under hydrologic regimes likely in the future; and 3. discuss future information and monitoring needs, including proposals for valley-wide biodiversity surveys, which would be helpful when considering withdrawn Bureau of Reclamation (BR) lands for possible incorporation into the Refuge. Several presentations at the beginning of the workshop provided a common basis for discussing these objectives. Refuge staff provided background on the history and past management. The Nature Conservatory discussed their role in the settlement act, proposals for valley-wide biodiversity surveys, and results of a literature review for Stillwater Marsh and the Lahontan Valley (Nachlinger 1993). Kay Fowler provided an historical context of changes in vegetation and waterbird use of the marshes based on her ethnography of the local Paiute Indians (Fowler 1993). Finally, Bob Elston discussed a model that predicts archaeological sites based on environmental variables (Raven and Elston 1989). The workshop was organized by staff from the Refuge and facilitated by the authors of this report. Participants included Ron Anglin, Bill Henry, Anne Janik, Cliff Creger, Fred Paveglio, and Mary Jo Elpers of the U.S. Fish and Wildlife Service (the Service); Jeff Baumgartner, Jan Nachlinger, Hope Humphries, and Graham Chisholm of The Nature Conservancy; David Yardas of the Environmental Defense Fund; David Robertson of Robertson Software, Inc.; Norm Saake, Terry Retterer, and Larry Neel of the Nevada Department of Wildlife; Lew Oring and Kay Fowler of the University of Nevada; and Robert Elston of Intermountain Research.

Report↗

Basic ground-water hydrology

Ground water is one of the Nation's most valuable natural resources. It is the source of about 40 percent of the water used for all purposes exclusive of hydropower generation and electric powerplant cooling. Surprisingly, for a resource that is so widely used and so important to the health and to the economy of the country, the occurrence of ground water is not only poorly understood but is also, in fact, the subject of many widespread misconceptions. Common misconceptions include the belief that ground water occurs in underground rivers resembling surface streams whose presence can be detected by certain individuals. These misconceptions and others have hampered the development and conservation of ground water and have adversely affected the protection of its quality. In order for the Nation to receive maximum benefit from its ground-water resource, it is essential that everyone, from the rural homeowner to managers of industrial and municipal water supplies to heads of Federal and State water-regulatory agencies, become more knowledgeable about the occurrence, development, and protection of ground water. This report has been prepared to help meet the needs of these groups, as well as the needs of hydrologists, well drillers, and others engaged in the study and development of ground-water supplies. It consists of 45 sections on the basic elements of ground-water hydrology, arranged in order from the most basic aspects of the subject through a discussion of the methods used to determine the yield of aquifers to a discussion of common problems encountered in the operation of ground-water supplies. Each section consists of a brief text and one or more drawings or maps that illustrate the main points covered in the text. Because the text is, in effect, an expanded discussion of the illustrations, most of the illustrations are not captioned. However, where more than one drawing is included in a section, each drawing is assigned a number, given in parentheses, and these numbers are inserted at places in the text where the reader should refer to the drawing. In accordance with U.S. Geological Survey policy to encourage the use of metric units, these units are used in most sections. In the sections dealing with the analysis of aquifer (pumping) test data, equations are given in both consistent units and in the inconsistent inch-pound units still in relatively common use among ground-water hydrologists and well drillers. As an aid to those who are not familiar with metric units and with the conversion of ground-water hydraulic units from inch-pound units to metric units, conversion tables are given on the inside back cover. Definitions of ground-water terms are given where the terms are first introduced. Because some of these terms will be new to many readers, abbreviated definitions are also given on the inside front cover for convenient reference by those who wish to review the definitions from time to time as they read the text. Finally, for those who need to review some of the simple mathematical operations that are used in ground-water hydrology, a section on numbers, equations, and conversions is included at the end of the text.

Water Supply Paper↗

Accelerating advances in continental domain hydrologic modeling

In the past, hydrologic modeling of surface water resources has mainly focused on simulating the hydrologic cycle at local to regional catchment modeling domains. There now exists a level of maturity among the catchment, global water security, and land surface modeling communities such that these communities are converging toward continental domain hydrologic models. This commentary, written from a catchment hydrology community perspective, provides a review of progress in each community toward this achievement, identifies common challenges the communities face, and details immediate and specific areas in which these communities can mutually benefit one another from the convergence of their research perspectives. Those include: (1) creating new incentives and infrastructure to report and share model inputs, outputs, and parameters in data services and open access, machine-independent formats for model replication or reanalysis; (2) ensuring that hydrologic models have: sufficient complexity to represent the dominant physical processes and adequate representation of anthropogenic impacts on the terrestrial water cycle, a process-based approach to model parameter estimation, and appropriate parameterizations to represent large-scale fluxes and scaling behavior; (3) maintaining a balance between model complexity and data availability as well as uncertainties; and (4) quantifying and communicating significant advancements toward these modeling goals.

Water Resources Research↗

Selected contributions to ground-water hydrology by C.V. Theis, and a review of his life and work

This publication highlights two previously unpublished papers by C.V. Theis; each is augmented with a discussion that explains why he wrote the paper, attempts to discern why he did not publish the paper, and amplifies the information with reference material not included by Theis. 'A Primer on Anisotropy' was written in the early 1970's to provide practicing hydrogeologists of the day with a method of analyzing ground-water problems involving anisotropic hydraulic-conductivity distribution without using tensor mathematics. The equations were developed for horizontal flow through dipping beds with differing conductivities parallel and perpendicular to the bedding and for flow through dipping beds having three different hydraulic conductivities, one perpendicular to the bedding and two others parallel to the bedding, at an angle to the strike of the beds. Although most colleagues who reviewed the primer in the early 1970's encouraged its publication enthusiastically, at least one suggested the addition of some examples in which the method would be demonstrated. Handwritten notes from Theis' files indicate that he may have worked on some examples and possibly other additions to the paper. The comments by Charles A. Appel include some examples of the primer's use and augment the presentation with references to relevant published papers, both those available to Theis but not cited by him, and subsequent publications. 'Aquifers, Ground-Water Bodies, and Hydrophers' was written in the early 1980's as an attempt to clarify the semantic and conceptual confusion in the use of the term aquifer, applied by some investigators to the saturated part of a permeable formation and by others to the entire permeable formation. The physical distinction between the aquifer and the ground-water body is emphasized, and the term hydropher is proposed to describe the saturated part of a permeable formation. Theis' interest in and familiarity with the French literature on ground water was the basis for a discussion of the French usage, which eschews the term aquifer. The analysis and critique of Theis' palzler explains the 1835 paper from which aquifer was reportedly derived, and provides further justification for the term hydropher. Theis' more important contributions to ground-water hydrology were outgrowths of his solutions to small local water problems based on field investigations. The biographical sketch, drawing extensively from a partial autobiography that Theis had dictated, reveals both the reasons for and the intellectual processes that led to his development of the nonequilibrium concept of ground-water hydraulics. The sketch also describes the background of the man, reviews his career, and portrays the admiration and respect he elicited from his colleagues and associates. The magnitude of Theis' contribution to the science of ground-water hydrology, to the appraisal of the water resources of New Mexico, and to the early research on ground disposal of radioactive wastes is evident from the bibliography of his writings, which includes 168 reports, many of them unpublished. The evolution of his thinking about the role of geologic inhomogeneities in mass transport, conceptualized but not quantified, was the major contribution of the latter part of his career.

Water Supply Paper↗

Water-quality and algal conditions in the North Umpqua River Basin, Oregon, 1992-95, and implications for resource management

This report describes the results of a synoptic water-quality and algal investigation during July 1995 at 36 stream sites in a 1,350 square-mile area of the North Umpqua River Basin, Oregon. The study area includes a headwaters hydroelectric project area, a Wild and Scenic reach in the main stem immediately downstream, and the watersheds of several major tributaries. Additional data from previous investigations are reviewed, and impacts on water quality in the Wild and Scenic reach from resource management, including forestry and reservoir operations, are inferred where sufficient data exist. Water-quality standards were occasionally exceeded for dissolved oxygen and pH, and daily maximum stream temperatures in the Wild and Scenic reach were higher than both the 1996 standard for the State of Oregon and the optimal temperature ranges for many anadromous fish. Dissolved oxygen in the basin was controlled more by stream temperature and reaeration than by primary production. Arsenic concentrations in the river during low flow (1 µg/L [microgram per liter]) indicate a potential cancer risk of between 1:5,000 and 1:20,000 for people using the river as a source of drinking water and fish for consumption. Streambed-sediment concentrations of arsenic, chromium, copper, manganese, and nickel were approximately double the sediment-quality criteria values adopted by New York State and by the Ontario Ministry of the Environment. High concentrations of phosphorus in bed sediments indicated that much of the phosphorus observed in the water column throughout the basin (medians: 32, 9, and 50 µg/L in the main stem, tributaries, and hydroelectric project areas, respectively) could have been geologically derived. Inorganic and organic nitrogen concentrations in water were mostly below minimum reporting limits (5 and 200 µg/L, respectively), indicating severe nitrogen limitation at most locations. Benthic algal biomass, biovolume, and chlorophyll a concentrations were highest at the sites directly below impoundments and at one headwater tributary (medians: 46 grams per square meter, 821 million cubic micrometers per square centimeter, and 126 milligrams per square meter, respectively), and were also somewhat elevated downstream in the Wild and Scenic reach compared with those in similar streams in the Pacific Northwest. Classification of the algal taxa indicated that, among all sites sampled, alkaliphilic taxa, nitrogen fixing taxa, and eutrophic taxa were the most abundant on the basis of biovolume and density. Cold-water taxa, facultative nitrogen heterotrophs, and oligotrophic taxa constituted the remainder of the taxa. Multivariate analyses indicated that algal communities at the hydroelectric-project-affected sites were distinct from communities at sites on the main stem and Steamboat Creek. At many locations, the river’s algal community might be compensating for the low nitrogen concentrations by fixation of atmospheric nitrogen or through heterotrophic assimilation of organic nitrogen. Water quality in the Wild and Scenic reach is dominated by water released from the hydroelectric project area during summer. Effects of the hydroelectric project include seasonal control of streamflow, water temperature, and phosphorus concentrations, and the possible release of low but ecologically important concentrations of organic nitrogen. A review of available data and literature suggests that the reservoirs can increase the interception of sediments and large organic debris, and promote their conversion into fine-grained particulate and dissolved organic matter for downstream transport. These effects could be compounded by the effects of forestry in the basin, including alteration of hydrologic cycles, changes in sediment and nutrient runoff, reductions of the transport of large woody debris, and degradation of habitat quality. It is hypothesized that, in the North Umpqua River, these processes have induced a fundamental shift in the river’s food web, from a detritus-based system to a system with a 2 higher emphasis on algal production. Confirmation of these changes and their effects on higher trophic levels are needed to properly manage the aquatic resources for all designated beneficial uses in the basin.

Oregon↗

User's manual for computer program BASEPLOT

The checking and reviewing of daily records of streamflow within the U.S. Geological Survey is traditionally accomplished by hand-plotting and mentally collating tables of data. The process is time consuming, difficult to standardize, and subject to errors in computation, data entry, and logic. In addition, the presentation of flow data on the internet requires more timely and accurate computation of daily flow records. BASEPLOT was developed for checking and review of primary streamflow records within the U.S. Geological Survey. Use of BASEPLOT enables users to (1) provide efficiencies during the record checking and review process, (2) improve quality control, (3) achieve uniformity of checking and review techniques of simple stage-discharge relations, and (4) provide a tool for teaching streamflow computation techniques. The BASEPLOT program produces tables of quality control checks and produces plots of rating curves and discharge measurements; variable shift (V-shift) diagrams; and V-shifts converted to stage-discharge plots, using data stored in the U.S. Geological Survey Automatic Data Processing System database. In addition, the program plots unit-value hydrographs that show unit-value stages, shifts, and datum corrections; input shifts, datum corrections, and effective dates; discharge measurements; effective dates for rating tables; and numeric quality control checks. Checklist/tutorial forms are provided for reviewers to ensure completeness of review and standardize the review process. The program was written for the U.S. Geological Survey SUN computer using the Statistical Analysis System (SAS) software produced by SAS Institute, Incorporated.

Open-File Report↗

Estimation of ground motion parameters

Strong motion data from western North America for earthquakes of magnitude greater than 5 are examined to provide the basis for estimating peak acceleration, velocity, displacement, and duration as a function of distance for three magnitude classes. Data from the San Fernando earthquake are examined to assess the effects of associated structures and of geologic site conditions on peak recorded motions. Small but statistically significant differences are observed in peak values of horizontal acceleration, velocity, and displacement recorded on soil at the base of small structures compared with values recorded at the base of large structures. Values of peak horizontal acceleration recorded at soil sites in the San Fernando earthquake are not significantly different from the values recorded at rock sites, but values of peak horizontal velocity and displacement are significantly greater at soil sites than at rock sites. Three recently published relationships for predicting peak horizontal acceleration are compared and discussed. Considerations are reviewed relevant to ground motion predictions at close distances where there are insufficient recorded data points.

Open-File Report↗