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USGS1992

Remote sensing studies of the geomorphology of Surtsey, 1987-1991

The volcanic island of Surtsey, formed by explosive submarine and effusive subaerial eruptions between November 1963 and June 1967, consists of a complex combination of primary and redeposited tephra and alkaline olivine basalt lava flows in a 2.5 km 2 area (Thorarinsson, 1967; Thorarinsson et al., 1964; Fridriksson, 1975). During the past 24 years, wave and wind erosion of this subaerial mid-ocean ridge (MOR) vent complex have modified Surtsey's coastal morphology, including the deposition of a 0.5 km-long northern peninsula ( ness ) composed of tephra and rounded lava fragments derived from the southern half of the island. Detailed geomorphologic and sedimentologic mapping of the various surface units now present on Surtsey has been accomplished throughout the history of the evolving island, most recently by Calles et al. (1980) and Ingolfsson (1980). On the basis of these studies, an effort to quantify the topographic characteristics of the primary geomorphic units on the island was initiated by the National Aeronautics and Space Administration (NASA) and the United States Geological Survey (USGS) in 1987. The objective has been to directly measure the microtopographic properties of the widest range of surface types possible, with special emphasis on the pristine or dynamic types. While large-scale topographic maps of Surtsey were prepared in 1968 and 1975 (Norrman, 1980; Norrman and Erlingsson, 1991; Calles et al, 1980), and geodetic leveling surveys have been carried out (Moore, 1980), there have been no recent attempts to geodetically determine the local topography of the island. Because of the rapid rates of geomorphic processes, such as erosion and deposition, on a small, geologically isolated volcanic island such as Surtsey, it is desirable to determine the meter-scale topographic character of its surface units and landforms, and later a remeasurement of the same surfaces to further quantify volumetric change, subsidence, and process rates. In addition, precise measurements of sub-meter-scale topography of pristine geologic surfaces provides necessary data for the investigation of whether various geologic processes demonstrate fractal or self-affine behavior at a range of length-scales within the interval 0.1 in to 1 km. Thus Surtsey offers a unique opportunity to apply new remote sensing techniques to the measurement of the evolving surface "roughness" characteristics of pristine geologic surfaces within an historically well-monitored environment.

Surtsey Research Progress Report↗

USGS2002

Application of GIS for assessing human vulnerability to cyclone in India

This paper presents the use of GIS to assess human vulnerability due to cyclonic storm in India. Human vulnerability is conceptualized here as the exposure to hazard by external activity (e.g. cyclone) and coping capacity of the people to reduce the risk. The assessment looks at the potential exposure to people impacted by cyclonic activity in 32 Indian states and locates the vulnerable population. The paper also explores how the coping capacity of the people is related to reduce vulnerability. Integrating a variety GIS data like path of cyclone tracks, demographic distribution, and Poverty data, this study evaluates the vulnerability of the people living in cyclonic zones in India. GIS helps as a powerful tool of measuring and characterizing the potential harm to people arising from extreme variability. Through this application location of vulnerable population could be identified in a geographic domain, where the government and concerned agencies can pay special attention.

Conference Paper↗

USGS2012

Status of groundwater quality in the Coastal Los Angeles Basin, 2006-California GAMA Priority Basin Project

Groundwater quality in the approximately 860-square-mile (2,227-square-kilometer) Coastal Los Angeles Basin study unit (CLAB) was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study area is located in southern California in Los Angeles and Orange Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA CLAB study was designed to provide a spatially unbiased assessment of the quality of untreated (raw) groundwater in the primary aquifer system. The assessment is based on water-quality and ancillary data collected in 2006 by the USGS from 69 wells and on water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer system was defined by the depth interval of the wells listed in the CDPH database for the CLAB study unit. The quality of groundwater in the primary aquifer system may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. This study assesses the status of the current quality of the groundwater resource by using data from samples analyzed for volatile organic compounds (VOCs), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources in the primary aquifer system of the CLAB study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal and (or) California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration greater than (>) 1.0 indicates a concentration greater than a benchmark, and a relative-concentration less than or equal to (≤) 1.0 indicates a concentration equal to or less than a benchmark. Relative-concentrations of organic and special-interest constituents [perchlorate, N -nitrosodimethylamine (NDMA), 1,2,3-trichloropropane (1,2,3-TCP), and 1,4-dioxane] were classified as "high" (relative-concentration>1.0), "moderate" (0.5 status assessment for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifer system with a relative-concentration greater than 1.0 for a particular constituent or class of constituents; percentage is based on an areal rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the percentage of the primary aquifer system with moderate and low relative-concentrations, respectively. Two statistical approaches-grid-based and spatially weighted-were used to evaluate aquifer-scale proportions for individual constituents and classes of constituents. Grid-based and spatially weighted estimates were comparable in the CLAB study unit (within 90-percent confidence intervals). Inorganic constituents with human-health benchmarks were detected at high relative-concentrations in 5.6 percent of the primary aquifer system and moderate in 26 percent. High aquifer-scale proportion of inorganic constituents primarily reflected high aquifer-scale proportions of arsenic (1.9 percent), nitrate (1.9 percent), and uranium (1.2 percent). Inorganic constituents with secondary maximum contaminant levels (SMCL) were detected at high relative-concentrations in 18 percent of the primary aquifer system and moderate in 47 percent. The constituents present at high relative-concentrations included total dissolved solids (1.9 percent), manganese (15 percent), and iron (9.4 percent). Relative-concentrations of organic constituents (one or more) were high in 3.7 percent, and moderate in 13 percent, of the primary aquifer system. The high aquifer-scale proportion of organic constituents primarily reflected high aquifer-scale proportions of solvents, including trichloroethene (TCE; 1.7 percent), perchloroethene (PCE; 1.1 percent), and carbon tetrachloride (1.0 percent). Of the 204 organic constituents analyzed, 44 constituents were detected. Eleven organic constituents had detection frequencies of greater than 10 percent: the trihalomethanes chloroform and bromodichloromethane, the solvents TCE, PCE, cis -1,2-dichloroethene, and 1,1-dichloroethene, the herbicides atrazine, simazine, prometon, and tebuthiuron, and the gasoline additive methyl tert -butyl ether (MTBE). Most detections were at low relative-concentrations. The special-interest constituent perchlorate was detected at high relative-concentrations in 0.5 percent of the primary aquifer system, and at moderate relative-concentrations in 35 percent. The special-interest constituent 1,4-dioxane was detected at high relative-concentrations, but an insufficient number of samples was analyzed to provide a representative estimate of aquifer-scale proportion.

California↗

USGS2014

Groundwater-quality data in seven GAMA study units: results from initial sampling, 2004-2005, and resampling, 2007-2008, of wells: California GAMA Program Priority Basin Project

The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The GAMA-PBP began sampling, primarily public supply wells in May 2004. By the end of February 2006, seven (of what would eventually be 35) study units had been sampled over a wide area of the State. Selected wells in these first seven study units were resampled for water quality from August 2007 to November 2008 as part of an assessment of temporal trends in water quality by the GAMA-PBP. The initial sampling was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within the seven study units. In the 7 study units, 462 wells were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study area. Wells selected this way are referred to as grid wells or status wells. Approximately 3 years after the initial sampling, 55 of these previously sampled status wells (approximately 10 percent in each study unit) were randomly selected for resampling. The seven resampled study units, the total number of status wells sampled for each study unit, and the number of these wells resampled for trends are as follows, in chronological order of sampling: San Diego Drainages (53 status wells, 7 trend wells), North San Francisco Bay (84, 10), Northern San Joaquin Basin (51, 5), Southern Sacramento Valley (67, 7), San Fernando–San Gabriel (35, 6), Monterey Bay and Salinas Valley Basins (91, 11), and Southeast San Joaquin Valley (83, 9). The groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOCs], pesticides, and pesticide degradates), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), and naturally-occurring inorganic constituents (nutrients, major and minor ions, and trace elements). Naturally-occurring isotopes (tritium, carbon-14, and stable isotopes of hydrogen and oxygen in water) also were measured to help identify processes affecting groundwater quality and the sources and ages of the sampled groundwater. Nearly 300 constituents and water-quality indicators were investigated. Quality-control samples (blanks, replicates, and samples for matrix spikes) were collected at 24 percent of the 55 status wells resampled for trends, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a noticeable source of bias in the data for the groundwater samples. Differences between replicate samples were mostly within acceptable ranges, indicating acceptably low variability in analytical results. Matrix-spike recoveries were within the acceptable range (70 to 130 percent) for 75 percent of the compounds for which matrix spikes were collected. This study did not attempt to evaluate the quality of water delivered to consumers. After withdrawal, groundwater typically is treated, disinfected, and blended with other waters to maintain acceptable water quality. The benchmarks used in this report apply to treated water that is served to the consumer, not to untreated groundwater. To provide some context for the results, however, concentrations of constituents measured in these groundwater samples were compared with benchmarks established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH). Comparisons between data collected for this study and benchmarks for drinking water are for illustrative purposes only and are not indicative of compliance or non-compliance with those benchmarks. Most constituents that were detected in groundwater samples from the trend wells were found at concentrations less than drinking-water benchmarks. Four VOCs—trichloroethene, tetrachloroethene, 1,2-dibromo-3-chloropropane, and methyl tert-butyl ether—were detected in one or more wells at concentrations greater than their health-based benchmarks, and six VOCs were detected in at least 10 percent of the samples during initial sampling or resampling of the trend wells. No pesticides were detected at concentrations near or greater than their health-based benchmarks. Three pesticide constituents—atrazine, deethylatrazine, and simazine—were detected in more than 10 percent of the trend-well samples during both sampling periods. Perchlorate, a constituent of special interest, was detected more frequently, and at greater concentrations during resampling than during initial sampling, but this may be due to a change in analytical method between the sampling periods, rather than to a change in groundwater quality. Another constituent of special interest, 1,2,3-TCP, was also detected more frequently during resampling than during initial sampling, but this pattern also may not reflect a change in groundwater quality. Samples from several of the wells where 1,2,3-TCP was detected by low-concentration-level analysis during resampling were not analyzed for 1,2,3-TCP using a low-level method during initial sampling. Most detections of nutrients and trace elements in samples from trend wells were less than health-based benchmarks during both sampling periods. Exceptions include nitrate, arsenic, boron, and vanadium, all detected at concentrations greater than their health-based benchmarks in at least one well during both sampling periods, and molybdenum, detected at concentrations greater than its health-based benchmark during resampling only. The isotopic ratios of oxygen and hydrogen in water and tritium and carbon-14 activities generally changed little between sampling periods, suggesting that the predominant sources and ages of groundwater in most trend wells were consistent between the sampling periods.

California↗

USGS2006

The Amphibian Research and Monitoring Initiative (ARMI): 5-year report

The Amphibian Research and Monitoring Initiative (ARMI) is an innovative, multidisciplinary program that began in 2000 in response to a congressional directive for the Department of the Interior to address the issue of amphibian declines in the United States. ARMI’s formulation was cross-disciplinary, integrating U.S. Geological Survey scientists from Biology, Water, and Geography to develop a course of action (Corn and others, 2005a). The result has been an effective program with diverse, yet complementary, expertise. ARMI’s approach to research and monitoring is multiscale. Detailed investigations focus on a few species at selected local sites throughout the country; monitoring addresses a larger number of species over broader areas (typically, National Parks and National Wildlife Refuges); and inventories to document species occurrence are conducted more extensively across the landscape. Where monitoring is conducted, the emphasis is on an ability to draw statistically defensible conclusions about the status of amphibians. To achieve this objective, ARMI has instituted a monitoring response variable that has nationwide applicability. At research sites, ARMI focuses on studying species/environment interactions, determining causes of observed declines, and developing new techniques to sample populations and analyze data. Results from activities at all scales are provided to scientists, land managers, and policymakers, as appropriate. The ARMI program and the scientists involved contribute significantly to understanding amphibian declines at local, regional, national, and international levels. Within National Parks and National Wildlife Refuges, findings help land managers make decisions applicable to amphibian conservation. For example, the National Park Service (NPS) selected amphibians as a vital sign for several of their monitoring networks, and ARMI scientists provide information and assistance in developing monitoring methods for this NPS effort. At the national level, ARMI has had major exposure at a variety of meetings, including a dedicated symposium at the 2004 joint meetings of the Herpetologists’ League, the American Society of Ichthyologists and Herpetologists, and the Society for the Study of Amphibians and Reptiles. Several principal investigators have brought international exposure to ARMI through venues such as the World Congress of Herpetology in South Africa in 2005 (invited presentation by Dr. Gary Fellers), the Global Amphibian Summit, sponsored by the International Union for Conservation of Nature (IUCN) and Wildlife Conservation International, in Washington, D.C., 2005 (invited participation by Dr. P.S. Corn), and a special issue of the international herpetological journal Alytes focused on ARMI in 2004 (edited by Dr. C.K. Dodd, Jr.). ARMI research and monitoring efforts have addressed at least 7 of the 21 Threatened and Endangered Species listed by the U.S. Fish and Wildlife Service (California red-legged frog [Rana draytonii], Chiricahua leopard frog [R. chiricahuensis], arroyo toad [Bufo californicus], dusky gopher frog [Rana sevosa], mountain yellow-legged frog [R. muscosa], flatwoods salamander [Ambystoma cingulatum], and the golden coqui [Eleutherodactylus jasperi]), and 9 additional species of concern recognized by the IUCN. ARMI investigations have addressed time-sensitive research, such as emerging infectious diseases and effects on amphibians related to natural disasters like wildfire, hurricanes, and debris flows, and the effects of more constant, environmental change, like urban expansion, road development, and the use of pesticides. Over the last 5 years, ARMI has partnered with an extensive list of government, academic, and private entities. These partnerships have been fruitful and have assisted ARMI in developing new field protocols and analytic tools, in using and refining emerging technologies to improve accuracy and efficiency of data handling, in conducting amphibian disease, malformation, and environmental effects research, and in implementing a network of monitoring and research sites. Accomplishments from these endeavors include more than 40 publications on amphibian status and trends, nearly 100 publications on amphibian ecology and causes of declines, and over 30 methodological publications. Several databases have emerged as a result of ARMI and its partnerships; one, a digital atlas of ranges for all U.S. amphibian species, was used by the IUCN to display amphibian distribution maps in the Global Amphibian Assessment Project. Given the scope of ARMI and the panoply of projects, findings have had implications for policy. Investigations that demonstrate amphibian declines or illuminate causes of declines provide valuable information about habitat management, environmental effects, mechanisms for the spread of disease, and human/amphibian interfaces. This information has been made available to land managers, scientists, educators, Congress and other policymakers, and the public. The support afforded ARMI by Congress has been influential in the program’s development and success. The value of ARMI’s efforts will continue to increase as we are able to extend our studies spatially and temporally to answer critical questions with more confidence. We are using ARMI’s resources efficiently and continuing to develop innovative mechanisms for leveraging resources for maximum effectiveness during challenging financial times. This report is a 5-year retrospective of the structure, methodology, progress, and contributions to the broader scientific community that have resulted from this national USGS program. We evaluate ARMI’s success to date, with regard to the challenges faced by the program and the strengths that have emerged. We chart objectives for the next 5 years that build on current accomplishments, highlight areas meriting further research, and direct efforts to overcome existing weaknesses.

Scientific Investigations Report↗

USGS1998

C4 photosynthetic modifications in the evolutionary transition from land to water in aquatic grasses

Cladistic analysis supports the conclusion that the Orcuttieae tribe of C 4 grasses reflect evolution from a terrestrial ancestry into seasonal pools. All nine species in the tribe exhibit adaptations to the aquatic environment, evident in the structural characteristics of the juvenile foliage, which persist submerged for 1–3 months prior to metamorphosis to the terrestrial foliage. Aquatic leaves of the least derived or basal genus Neostapfia have few morphological and anatomical characteristics specialized to the aquatic environment and have retained full expression of the C 4 pathway, including Kranz anatomy. Orcuttia species have many derived characteristics and are more specialized to the aquatic environment. These latter species germinate earlier in the season and persist in the submerged stage longer than Neostapfia and evidence from the literature indicates length of submergence is positively correlated with fitness components. Aquatic leaves of Orcuttia species lack Kranz or PCR bundle sheath anatomy, yet 14 C-pulse chase studies indicate >95% malate + aspartate as the initial products of photosynthesis and these products turn over rapidly to phosphorylated sugars, indicating a tight coupling of the C 4 and C 3 cycles. Presence of the C 4 pathway is further supported by enzymological data. Contemporary dogma that Kranz anatomy is a sine qua non for operation of the C 4 pathway is contradicted by the patterns in Orcuttia ; however, it is unknown whether the pathway acts as a CO 2 concentrating mechanism in these aquatic plants.

California↗

USGS2016

Getting quantitative about consequences of cross-ecosystem resource subsidies on recipient consumers

Most studies of cross-ecosystem resource subsidies have demonstrated positive effects on recipient consumer populations, often with very large effect sizes. However, it is important to move beyond these initial addition–exclusion experiments to consider the quantitative consequences for populations across gradients in the rates and quality of resource inputs. In our introduction to this special issue, we describe at least four potential models that describe functional relationships between subsidy input rates and consumer responses, most of them asymptotic. Here we aim to advance our quantitative understanding of how subsidy inputs influence recipient consumers and their communities. In the papers following, fish were either the recipient consumers or the subsidy as carcasses of anadromous species. Advancing general, predictive models will enable us to further consider what other factors are potentially co-limiting (e.g., nutrients, other population interactions, physical habitat, etc.) and better integrate resource subsidies into consumer–resource, biophysical dynamics models.

Canadian Journal of Fisheries and Aquatic Sciences↗

USGS2010

Vegetation classification and distribution mapping report: Canyon de Chelly National Monument

Executive Summary: The classification and distribution mapping of the vegetation of Canyon de Chelly National Monument (CACH) and surrounding environment was accomplished through a multi-agency effort between 2003 and 2007. The National Park Service’s Southern Colorado Plateau Network facilitated the team that conducted the work, which comprised the U.S. Geological Survey’s Southwest Biological Science Center and Fort Collins Science Center, Navajo Natural Heritage Program, Northern Arizona University, and NatureServe. The project team described 48 plant communities for CACH—35 of which were described from quantitative classification based on field-relevé data collected in 2004. Five additional plant communities were based on field relevés collected in a previous study. The team derived four additional plant communities from field observations during the photointerpretation phase of the project, and field documented them during accuracy assessment. The National Vegetation Classification Standard served as a conceptual framework for assigning these plant communities to the alliance and association level. Ten of the 48 plant communities were designated “park specials”, that is, plant communities with insufficient data to describe them as new alliances or associations. The project team also developed a spatial vegetation map database representing CACH, with three different map-class schemas: base, group, and management map classes. The base map classes represented the finest level of spatial detail. Photointerpreters delineated initial polygons through manual interpretation of 2003/2004 1:12,000-scale true color aerial photography supplemented by occasional computer screen digitizing on a mosaic of digitized aerial photos. These polygons were labeled with base map classes during photointerpretation. Field visits verified interpretation concepts. The vegetation map database includes • ? 53 base map classes, which consist of associations and park specials classified with the quantitative analysis • ? additional associations noted during photointerpretation • ? non-vegetated land cover, such as infrastructure, land use, and geological land cover. The base map classes consist of 4,718 polygons in the project area. A field-based accuracy assessment of the base map classes showed the overall accuracy to be 50.8% The group map classes represent aggregations of the base map classes, approximating the group level of the National Vegetation Classification Standard, Version 2 (Federal Geographic Data Committee 2008). Terrestrial ecological systems, as described by NatureServe (Comer et al. 2003), were used as a first approximation of the group level. The project team identified 16 group map classes in this project. The overall accuracy of the group map classes was determined using the same accuracy assessment data as for the base map classes. The overall accuracy of the group representation of vegetation was 79.9%. In consultation with park staff, the team developed management map classes that consisted of park-defined groupings of base map classes and were intended to represent a balance between maintaining required accuracy and providing a focus on vegetation of particular interest or import to park managers. The 28 management map classes have an overall accuracy of 77.1%. While the main products of this project are the vegetation classification and the vegetation map database, a number of ancillary geographic information system and digital database products were also produced that can be used independently, or to augment the main products. These products include shapefiles of the location of field-collected data and relational databases of field-collected data.

Report↗

USGS2002

A passive microwave snow depth algorithm with a proxy for snow metamorphism

Passive microwave brightness temperatures of snowpacks depend not only on the snow depth, but also on the internal snowpack properties, particularly the grain size, which changes through the winter. Algorithms that assume a constant grain size can yield erroneous estimates of snow depth or water equivalent. For snowpacks that are subject to temperatures well below freezing, the bulk temperature gradient through the snowpack controls the metamorphosis of the snow grains. This study used National Weather Service (NWS) station measurements of snow depth and air temperature from the Northern US Great Plains to determine temporal and spatial variability of the snow depth and bulk snowpack temperature gradient. This region is well suited for this study because it consists primarily of open farmland or prairie, has little relief, is subject to very cold temperatures, and has more than 280 reporting stations. A geostatistical technique called Kriging was used to grid the randomly spaced snow depth measurements. The resulting snow depth maps were then compared with the passive microwave observations from the Special Sensor Microwave Imager (SSM/I). Two snow seasons were examined: 1988-89, a typical snow year, and 1996-97, a record year for snow that was responsible for extensive flooding in the Red River Basin. Inspection of the time series of snow depth and microwave spectral gradient (the difference between the 19 and 37 GHz bands) showed that while the snowpack was constant, the spectral gradient continued to increase. However, there was a strong correlation (0.6 < R2 < 0.9) between the spectral gradient and the cumulative bulk temperature gradient through the snowpack (TGI). Hence, TGI is an index of grain size metamorphism that has occurred within the snowpack. TGI time series from 21 representative sites across the region and the corresponding SSM/I observations were used to develop an algorithm for snow depth that requires daily air temperatures. Copyright ?? 2002 John Wiley & Sons, Ltd.

Hydrological Processes↗

USGS2024

Comparative studies on extraction of sediment interstitial waters: Discussion and comment on the current state of interstitial water studies

The implication by Murthy and Ferrell (1972)that interstitial water studies are in a confused state is criticized on the basis that the authors have not drawn on a considerable body of data, especially Soviet studies since the 1950's, and results of the Deep Sea Drilling Project. Pressure filtration systems for extracting interstitial waters are currently the methods of choice for marine studies and have achieved substantial reliability and reproducibility. Although gaps and problems remain, many aspects of interstitial composition of marine sediments have been clarified; these include the substantial constancy of composition of interstitial waters in deep sea pelagic deposits, depletion of interstitial cations owing to authigenic mineral formation in more rapidly accumulated (especially terrigenous) sediments, and special phenomena in sediments overlying salt deposits.

Clays and Clay Minerals↗

USGS1964

Soil mechanics and soil physics symbols and nomenclature useful in hydrologic studies

The study of hydrology requires an interdisciplinary approach, incorporating knowledge from fields such as engineering, geology, chemistry, and agriculture. With increasing frequency, the hydrologist finds it necessary to study the literature of the soil mechanics and soil physics disciplines for assistance in the solution of hydrologic problems. Because of the inter-relation between hydrology and soil mechanics and soil physics, hydrologists also are preparing an increasing number of technical papers ·for use by these two disciplines. To permit the hydrologist to better understand specialized literature, as well as to assist him in preparing papers for these disciplines, this glossary of soil mechanics and soil physics nomenclature was prepared. It is a compilation from standards, dictionaries, and glossaries published by technical societies, and from reports by selected authorities in the fields of soil mechanics and soil physics. The variety of symbols and definitions presented for many of the terms demonstrates the difficulty that has been encountered over the years in reaching agreement on such a subject as nomenclature. Both old and new definitions and symbols are presented to assist the hydrologist in reading literature. Whenever possible the more recent symbols and nomenclature should be used by the hydrologist in writing papers for soil mechanics or soil physics audiences. When the hydrologist finds it necessary to use symbols or terms not included in the present list, he should try to select those not in conflict with the recent systems presented in this report. Symbols are listed in alphabetical order to assist readers in finding the term represented by a given symbol. Terms also are listed alphabetically, usually followed by recommended symbols and brief definitions. Where two or more symbols or definitions are listed following a term, no significance should be placed on the order of presentation. The source is indicated for each symbol, term, or definition, and the sources are listed in the cited references. It is emphasized that this report is only a compilation of nomenclature generally accepted in the soil mechanics apd soil physics disciplines. It does not necessarily represent the recommendations or usage of such nomenclature by the Geological Survey or any part of its organization.

Open-File Report↗

USGS1969

The Geologic Story of Mount Rainier

Ice-clad Mount Rainier, towering over the landscape of western Washington, ranks with Fuji-yama in Japan, Popocatepeti in Mexico, and Vesuvius in Italy among the great volcanoes of the world. At Mount Rainier, as at other inactive volcanoes, the ever-present possibility of renewed eruptions gives viewers a sense of anticipation, excitement, and apprehension not equaled by most other mountains. Even so, many of us cannot imagine the cataclysmic scale of the eruptions that were responsible for building the giant cone which now stands in silence. We accept the volcano as if it had always been there, and we appreciate only the beauty of its stark expanses of rock and ice, its flower-strewn alpine meadows, and its bordering evergreen forests. Mount Rainier owes its scenic beauty to many features. The broad cone spreads out on top of a major mountain range - the Cascades. The volcano rises about 7,000 feet above its 7,000-foot foundation, and stands in solitary splendor - the highest peak in the entire Cascade Range. Its rocky ice-mantled slopes above timberline contrast with the dense green forests and give Mount Rainier the appearance of an arctic island in a temperate sea, an island so large that you can see its full size and shape only from the air. The mountain is highly photogenic because of the contrasts it offers among bare rock, snowfields, blue sky, and the incomparable flower fields that color its lower slopes, shadows cast by the multitude of cliffs, ridges, canyons, and pinnacles change constantly from sunrise to sunset, endlessly varying the texture and mood of the mountain. The face of the mountain also varies from day to day as its broad snowfields melt during the summer. The melting of these frozen reservoirs makes Mount Rainier a natural resource in a practical as well as in an esthetic sense, for it ensures steady flows of water for hydroelectric power in the region, regardless of season. Seen from the Puget Sound country to the west, Mount Rainier has an unreal quality - its white summit, nearly 3 miles high, seems to float among the clouds. We share with the populace of the entire lowland a thrill as we watch skyward the evening's setting sun reddens the volcano's western snowfields. When you approach the mountain in its lovely setting, you may find something that appeals especially to you - the scenery, the wildlife, the glaciers, or the wildflowers. Or you may feel challenged to climb to the summit. Mount Rainier and its neighboring mountains have a special allure for a geologist because he visualizes the event - some ordinary, some truly spectacular - that made the present landscape. Such is the fascination of geology. A geologist becomes trained to see 'in his mind's eye' geologic events of thousands or even millions of years ago. And, most remarkable, he can 'see' these events by studying rocks in a cliff or roadcut, or perhaps by examining earthy material that looks like common soil beneath pastureland many miles away from the volcano. Our key to understanding the geology of Mount Rainier is that each geologic event can be reconstructed - or imagined - from the rocks formed at the time of the event. With this principle as our guide, we will review the geologic ancestry of this majestic volcano and learn what is behind its scenery.

Washington↗

USGS2010

EAARL coastal topography-western Florida, post-Hurricane Charley, 2004: seamless (bare earth and submerged.

Project Description These remotely sensed, geographically referenced elevation measurements of lidar-derived seamless (bare-earth and submerged) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Coastal and Marine Geology Program (CMGP), St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of a portion of the western Florida coastline beachface, acquired post-Hurricane Charley on August 17 and 18, 2004. The datasets are made available for use as a management tool to research scientists and natural-resource managers. An innovative airborne lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multispectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for sub-meter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom-built processing system developed in a NASA-USGS collaboration. ALPS supports the exploration and processing of lidar data in an interactive or batch mode. Modules for presurvey flight-line definition, flight-path plotting, lidar raster and waveform investigation, and digital camera image playback have been developed. Processing algorithms have been developed to extract the range to the first and last significant return within each waveform. ALPS is used routinely to create maps that represent submerged or sub-aerial topography. Specialized filtering algorithms have been implemented to determine the 'bare earth' under vegetation. For more information about similar projects, please visit the Decision Support for Coastal Science and Management website. Selected References Brock, J.C., Wright, C.W., Sallenger, A.H., Krabill, W.B., and Swift, R.N., 2002, Basis and methods of NASA airborne topographic mapper Lidar surveys for coastal studies: Journal of Coastal Research, v. 18, no. 1, p. 1-13. Crane, Michael, Clayton, Tonya, Raabe, Ellen, Stoker, Jason, Handley, Larry, Bawden, Gerald, Morgan, Karen, and Queija, Vivian, 2004, Report of the U.S. Geological Survey Lidar workshop sponsored by the Land Remote Sensing Program and held in St. Petersburg, FL, November 2002: U.S. Geological Survey Open-File Report 2004-1456, 72 p. Nayegandhi, Amar, Brock, J.C., and Wright, C.W., 2009, Small-footprint, waveform-resolving Lidar estimation of submerged and sub-canopy topography in coastal environments: International Journal of Remote Sensing, v. 30, no. 4, p. 861-878. Sallenger, A.H., Wright, C.W., and Lillycrop, Jeff, 2005, Coastal impacts of the 2004 hurricanes measured with airborne Lidar; initial results: Shore and Beach, v. 73, nos. 2-3, p. 10-14. Resources Included Readme.txt File

Data Series↗

USGS2011

An introduction to adaptive management for threatened and endangered species

Management of threatened and endangered species would seem to be a perfect context for adaptive management. Many of the decisions are recurrent and plagued by uncertainty, exactly the conditions that warrant an adaptive approach. But although the potential of adaptive management in these settings has been extolled, there are limited applications in practice. The impediments to practical implementation are manifold and include semantic confusion, institutional inertia, misperceptions about the suitability and utility, and a lack of guiding examples. In this special section of the Journal of Fish and Wildlife Management , we hope to reinvigorate the appropriate application of adaptive management for threatened and endangered species by framing such management in a decision-analytical context, clarifying misperceptions, classifying the types of decisions that might be amenable to an adaptive approach, and providing three fully developed case studies. In this overview paper, I define terms, review the past application of adaptive management, challenge perceived hurdles, and set the stage for the case studies which follow.

Journal of Fish and Wildlife Management↗

USGS2007

Demersal fishes associated with Lophelia pertusa coral and hard-substrate biotopes on the continental slope, northern Gulf of Mexico

The demersal fish fauna of Lophelia pertusa (Linnaeus, 1758) coral reefs and associated hard-bottom biotopes was investigated at two depth horizons in the northern Gulf of Mexico using a manned submersible and remote sampling. The Viosca Knoll fauna consisted of at least 53 demersal fish species, 37 of which were documented by submersible video. On the 325 m horizon, dominant taxa determined from frame-by-frame video analysis included Stromateidae, Serranidae, Trachichthyidae, Congridae, Scorpaenidae, and Gadiformes. On the 500 m horizon, large mobile visual macrocarnivores of families Stromateidae and Serranidae dropped out, while a zeiform microcarnivore assumed importance on reef "Thicket" biotope, and the open-slope taxa Macrouridae and Squalidae gained in importance. The most consistent faunal groups at both depths included sit-and-wait and hover-and-wait strategists (Scorpaenidae, Congridae, Trachichthyidae), along with generalized mesocarnivores (Gadiformes). The specialized microcarnivore, Grammicolepis brachiusculus Poey, 1873, appears to be highly associated with Lophelia reefs. The coral "Thicket" biotope was extensively developed on the 500 m site, but fish abundance was low with only 95 fish per hectare. In contrast to Lophelia reefs from the eastern the North Atlantic, the coral "Rubble" biotope was essentially absent. This study represents the first quantitative analysis of fishes associated with Lophelia reefs in the Gulf of Mexico, and generally in the western North Atlantic.

Gulf of Mexico↗

USGS2006

Special issue: The changing shapes of active volcanoes: Recent results and advances in volcano geodesy

The 18 papers herein report on new geodetic data that offer valuable insights into eruptive activity and magma transport; they present new models and modeling strategies that have the potential to greatly increase understanding of magmatic, hydrothermal, and volcano-tectonic processes; and they describe innovative techniques for collecting geodetic measurements from remote, poorly accessible, or hazardous volcanoes. To provide a proper context for these studies, we offer a short review of the evolution of volcano geodesy, as well as a case study that highlights recent advances in the field by comparing the geodetic response to recent eruptive episodes at Mount St. Helens. Finally, we point out a few areas that continue to challenge the volcano geodesy community, some of which are addressed by the papers that follow and which undoubtedly will be the focus of future research for years to come.

Journal of Volcanology and Geothermal Research↗

USGS1999

Contribution of research to management and recovery of the roseate tern: review of a twelve-year project

The Northwest Atlantic population of the Roseate Tern (Sterna dougallii) is largely confined to a small breeding area along the northeast coast of the USA between 40? and 42?N. This population was listed as endangered in the USA in 1987 because it was dangerously concentrated into a few breeding sites (85% on two islands in the 1980s). The nesting population in the area from Long Island, New York to Cape Cod, Massachusetts has been studied intensively since 1987, in conjunction with a program of management of the breeding colonies. This paper summarizes the results of the research program and discusses the extent to which it has contributed to effective management. The regional population now numbers about 4,000 breeding pairs and has been increasing slowly since 1987, except between 1991 and 1992 when it declined by about 17%. This decline was probably caused by Hurricane `Bob' in August 1991. Roseate Terns have specialized foraging habits and are concentrated into a small number of foraging areas near the nesting colonies. The historically important breeding sites were taken over by large gulls between 1930 and 1972. Many of the terns moved to less suitable sites near the mainland, where they are subject to predation by mainland-based predators. Despite this, Roseate Terns breed with high success at many sites. The sex-ratio is skewed towards females; about 12% of nests are attended by female-female pairs. The annual adult survival rate (0.83) is unusually low for a seabird. Most mortality occurs away from the breeding grounds, but the winter quarters remained unknown until one roost site was found in Brazil in 1995-1997. A major management goal has been to restore former colony-sites by eliminating nesting gulls, but the success of some of these projects has been questionable because they may have attracted birds to sites with higher levels of predation. Although the research has yielded important information about the biology and demography of the species, it has taken longer than expected to obtain and analyze data from multiple sites on this long-lived species. Most work has been carried out at breeding sites: critical studies on feeding ecology and winter ecology have been hampered by insufficient funding and the paucity of self-motivated biologists. Hence, the program has not yet provided all the keys to restoring the population.

Waterbirds↗

USGS2008

Richness and diversity of helminth communities in tropical freshwater fishes: Empirical evidence

Aim: Published information on the richness and diversity of helminth parasite communities in tropical freshwater fishes is reviewed in response to expectations of species-rich parasite communities in tropical regions. Location: Areas covered include the tropics and some subtropical areas. In addition, the north temperate area of the nearctic zone is included for comparison. Methods: Data from 159 communities in 118 species of tropical freshwater fish, summarized from 46 published studies, were used for this review. Parasite community descriptors used in the analyses included component community richness and calculated mean species richness. Data from 130 communities in 47 species of nearctic north temperate freshwater fish were summarized from 31 studies and used for comparison. Results: The component helminth communities of many tropical freshwater fish are species-poor, and considerable proportions of fish from certain parts of the tropics, e.g. West African drainages, are uninfected or lightly infected. Mean helminth species richness was low and equaled or exceeded 2.0 in only 22 of 114 communities. No single group of helminths was identified as a dominant component of the fauna and species composition was variable among and within broader geographical areas. The richest enteric helminth assemblages were found in mochokid and clariid catfish with a mixed carnivorous diet, whereas algal feeders, herbivores and detritivores generally had species-poor gut helminth communities. Comparisons indicated that certain areas in the north temperate region had higher helminth species richness in fishes than areas in the tropics. Main conclusions: Expectations of high species richness in helminth communities of tropical freshwater fishes are not fulfilled by the data. Direct comparisons of infracommunities and component communities in host species across widely separated phylogenetic and geographical lines are inappropriate. Examination of latitudinal differences in richness of monophyletic parasite groups or of compound communities may uncover patterns different from those found in this study. Richness of helminth communities may be ultimately determined not by the number of host species present but by the degree of divergence of host lineages and by their diversification modes. A phylogenetic framework for hosts and parasites will reveal if increased host species richness within host clades, when host speciation is accompanied by habitat or diet specialization, or both, leads to lower helminth diversity in host species by fragmentation of a core helminth fauna characteristic or specific of the larger host clade. This pattern may be analysed in the context of cospeciation and acquisition from other unrelated hosts (host-sharing or host-switching).

Journal of Biogeography↗