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USGS2016

Unsteady flow in natural compound channel: Experiment and simulation

Phragmites Australis, or common reed, is an invasive plant species that has spread along channels of the Platte River (Nebraska, USA), adversely altering the biogeomorphology of the system. Of particular interest have been the impacts on riparian habitat, specifically the reduction of suitable areas for crane roosting and shorebird nesting. A program for managing and removing these and other invasive plant species has been in place to mitigate these effects. Spraying and mechanical removal of phragmites has been the established practice, but there is interest in evaluating other potential forms of maintenance, in particular the potential of uprooting seedlings using high velocity/high shear flows. For that purpose, in 2010 a high flow experiment was conducted on a return channel to the Platte River that feeds from the Thirty Mile Canal near Brady, Nebraska. As part of the experiment, a 250-meter long reach of the channel was monitored and data were collected for the set-up, testing, and evaluation of numerical models. This article presents a description of the experimental conditions, data-collection program, and application of an unsteady, depth-averaged numerical model to reproduce the event.

Nebraska↗

USGS2006

Effects of summer flow augmentation on the migratory behavior and survival of juvenile Snake River fall Chinook salmon. Annual report 2005

This report summarizes results of research activities conducted in 2004 and years previous to aid in the management and recovery of fall Chinook salmon Oncorhynchus tshawytscha in the Columbia River basin. For detailed summaries, we refer the reader to the abstracts given on the second page of each chapter. The Annual Reporting section includes information provided to fishery managers in-season and post-season, and it contains a detailed summary of life history and survival statistics on wild Snake River fall Chinook salmon juveniles for the years 1992-2004. Publication is a high priority of our staff. Publication provides our results to a wide audience, and it insures that our work meets high scientific standards. The Bibliography of Published Journal Articles section provides citations for peer-reviewed papers co-authored by personnel of project 1991-02900 that were written or published from 1998 to 2005.

Idaho, Washington↗

USGS1965

Ground water in Jordan Valley, Salt Lake County, Utah

This article was compiled largely from a technical report on ground-water conditions in the Jordan Valley which was prepared as part of a cooperative program between the Utah State Engineer and the U.S. Geological Survey to study the water resources of Utah. If you would like to read the more detailed technical discusion, see “Geology and Ground-Water Resources of the Jordan Valley, Utah” by I. Wendell Marine and Don Price. It is Water-Resources Bulletin No. 7 of the Utah Geological and Mineralogical Survey.

Utah↗

USGS1995

Endangered cui-ui of Pyramid Lake, Nevada

Cui-ui ( Chasmistes cujus ) is a large plankton-feeding fish that only occurs in Pyramid Lake, Nevada. It was put on the federal endangered list in 1967 based on declining population and absence of reproduction. A lake dweller, cui-ui is a stream spawner. Most of this century, this sucker species was unable to access the Truckee River, Pyramid Lake's only perennial tributary, to reproduce. Water diversion from the Truckee River, as a result of the nation's first Bureau of Reclamation project (Newlands Project), reduced the lake elevation and, in most years, caused an impassable delta to form at the mouth of the Truckee River. Cui-ui live more than 40 years; it is this longevity that has allowed the species to persist for as many as 19 years with virtually no recruitment (see glossary) to the adult population (Scoppettone 1988). Cui-ui is one of three remaining species of the genus Chasmistes. Of the three, its habitat is most intact, and it thus has the best opportunity for recovery (Scoppettone and Vinyard 1991). Each spring, cui-ui adults, most of which mature at 8-12 years of age, migrate to the mouth of the Truckee River at the south end of Pyramid Lake, where they aggregate, awaiting environmental cues and sufficient stream flow to enter the river (Scoppettone et al. 1986). This behavior provides an excellent opportunity to capture the adults for estimating population numbers and year-class (year hatched) structure. In this article we report changes in adult cui-ui population number and year-class structure from spring 1983 to spring 1993.

Nevada↗

USGS1997

Field guide to the Mesozoic accretionary complex along Turnagain Arm and Kachemak Bay, south-central Alaska

Turnagain Arm, just east of Anchorage, provides a readily accessible, world-class cross section through a Mesozoic accretionary wedge. Nearly continuous exposures along the Seward Highway, the Alaska Railroad, and the shoreline of Turnagain Arm display the two main constituent units of the Chugach terrane: the McHugh Complex and Valdez Group. In this paper we describe seven bedrock geology stops along Turnagain Arm, and two others in the Chugach Mountains just to the north (Stops 1-7 and 9), which will be visited as part of the May, 1997 field trip of the Alaska Geological Society. Outcrops along Turnagain Arm have already been described in two excellent guidebook articles (Clark, 1981; Winkler and others 1984), both of which remain as useful and valid today as when first published. Since the early 1980's, studies along Turnagain Arm have addressed radiolarian ages of chert and conodont ages of limestone in the McHugh Complex (Nelson and others, 1986, 1987); geochemistry of basalt in the McHugh Complex (Nelson and Blome, 1991); post-accretion brittle faulting (Bradley and Kusky, 1990; Kusky and others, 1997); and the age and tectonic setting of gold mineralization (Haeussler and others, 1995). Highlights of these newer findings will described both in the text below, and in the stop descriptions. Superb exposures along the southeastern shore of Kachemak Bay show several other features of the McHugh Complex that are either absent or less convincing along Turnagain Arm. While none of these outcrops can be reached via the main road network, they are still reasonably accessible - all are within an hour by motorboat from Homer, seas permitting. Here, we describe seven outcrops along the shore of Kachemak Bay that we studied between 1989 and 1993 during geologic mapping of the Seldovia 1:250,000- scale quadrangle. These outcrops (Stops 61-67) will not be part of the 1997 itinerary, but are included here tor the benefit of those who may wish to visit them later.

Alaska↗

USGS1995

Pinyon-juniper woodlands

Pinyon-juniper woodlands are one of the largest ecosystems in the Southwest and in the Middle Rio Grande Basin (Fig. 1). The woodlands have been important to the region's inhabitants since prehistoric times for a variety of natural resources and amenities. The ecosystems have not been static; their distributions, stand characteristics, and site conditions have been altered by changes in climatic patterns and human use and, often, abuse. Management of these lands since European settlement has varied from light exploitation and benign neglect, to attempts to remove the trees in favor of forage for livestock, and then to a realization that these lands contain useful resources and should be managed accordingly. Land management agencies are committed to ecosystem management. While there are several definitions of ecosystem management, the goal is to use ecological approaches to create and maintain diverse, productive, and healthy ecosystems (Kaufmann et al. 1994). Ecosystem management recognizes that people are an integral part of the system and that their needs must be considered. Ecological approaches are central to the concept, but our understanding of basic woodland ecology is incomplete, and there are different opinions and interpretations of existing information (Gottfried and Severson 1993). There are many questions concerning proper ecosystem management of the pinyon-juniper woodlands and how managers can achieve these goals (Gottfried and Severson 1993). While the broad concept of ecosystem management generally is accepted, the USDA Forest Service, other public land management agencies, American Indian tribes, and private landowners may have differing definitions of what constitutes desired conditions. Key questions about the pinyon-juniper ecosystems remain unanswered. Some concern the basic dynamics of biological and physical components of the pinyon-juniper ecosystems. Others concern the distribution of woodlands prior to European settlement and changes since the introduction of livestock and fire control. This relates to whether tree densities have been increasing or whether trees are invading grasslands and, to a lesser extent, drier ponderosa pine (Pinus ponderosa) forests. In areas where woodlands were heavily used by American Indians for fuelwood prior to European contact, the advance of pinyon and juniper could represent the slow recovery from intensive use (Samuels and Betancourt 1982). There are numerous questions regarding declines in watershed condition related to changes in pinyon-juniper tree stand densities and to the density and composition of understory vegetation. There are different opinions about proper management of woodland ecosystems. Should these lands be managed for a single resource, such as forage for livestock production, or managed for sustained production of multiple resource products and amenities? Depending on site and stand conditions, the woodlands can produce variable quantities of fuelwood, pinyon nuts, wildlife habitat, forage for livestock, and cover for watershed protection. Management must also consider increasing recreational demands, threatened and endangered species, and protection of archeological sites. Many pinyon-juniper woodland watersheds in New Mexico have unsatisfactory soil and watershed conditions (USDA Forest Service 1993); managers must develop restoration procedures that recognize the value of woodland ecosystems. The concerns, questions, and conflicts surrounding management of pinyon-juniper lands, as well as the ecological foundations of ecosystem management, require that all interested parties reevaluate attitudes toward the woodlands. Ecosystem management goals and concepts recognize diversity. Pinyonjuniper woodlands are diverse, and stand characteristics and site productivities vary. Management objectives and prescriptions must evaluate the potential of each site, and decisions must be based on sound scientific information. This information is often unavailable. Therefore, this paper describes what we do know about the characteristics, distribution, and ecology of pinyon-juniper woodlands, including the effects of natural and human factors, within the southwestern United States and particularly the Middle Rio Grande Basin. It also reviews some past and present management options in this widespread and important vegetation type. The review draws on research and management information from the Rio Grande Basin and from similar areas in the Southwest and adjacent regions. It does not attempt to review all of the relevant literature; additional sources can be found within the articles cited in the References.

General Technical Report↗

USGS1999

Wetland restoration, flood pulsing, and disturbance dynamics

While it is generally accepted that flood pulsing and disturbance dynamics are critical to wetland viability, there is as yet no consensus among those responsible for wetland restoration about how best to plan for those phenomena or even whether it is really necessary to do so at all. In this groundbreaking book, Dr. Beth Middleton draws upon the latest research from around the world to build a strong case for making flood pulsing and disturbance dynamics integral to the wetland restoration planning process. While the initial chapters of the book are devoted to laying the conceptual foundations, most of the coverage is concerned with demonstrating the practical implications for wetland restoration and management of the latest ecological theory and research. It includes a fascinating case history section in which Dr. Middleton explores the restoration models used in five major North American, European, Australian, African, and Asian wetland projects, and analyzes their relative success from the perspective of flood pulsing and disturbance dynamics planning. Wetland Restoration also features a wealth of practical information useful to all those involved in wetland restoration and management, including: * A compendium of water level tolerances, seed germination, seedling recruitment, adult survival rates, and other key traits of wetland plant species * A bibliography of 1,200 articles and monographs covering all aspects of wetland restoration * A comprehensive directory of wetland restoration ftp sites worldwide * An extensive glossary of essential terms

Book↗

USGS2002

Response of seabirds to fluctuations in forage fish density

Following the Exxon Valdez Oil Spill (EVOS), one concern was that prevailing ecological conditions in the Gulf of Alaska (GOA) would not favor recovery of damaged seabird populations. To address this issue, we examined relationships between oceanography, forage fish and seabirds near three seabird colonies in lower Cook Inlet (LCI) in 1995-1999 (some colony work continued until 2001). Upwelling of cold, nutrient-rich GOA waters at the entrance to the shallow LCI estuary supports a high density of juvenile pollock, sand lance, and capelin; which in turn are exploited by high densities of breeding seabirds (murres, kittiwakes, puffins, etc.) on the east side of LCI. Waters on the west side of LCI are oceanographically distinct (warmer, less saline, outflowing), and much less productive for forage fish and seabirds. Patterns of seabird foraging behavior, productivity and population change reflected patterns of forage fish abundance and distribution, which in turn depended on local oceanography. Most seabird parameters varied with forage fish density in a non-linear (e.g., sigmoidal, exponential) fashion, and in some areas and years, productivity was limited by food availability. Current and projected ecological conditions favor recovery of seabirds from the EVOS at some colonies. In 14 chapters, this report summarizes data and compiles it into 247 tables, figures and appendices. Chapter 14 provides a thorough synthesis of overall project findings. Final analyses and interpretations of data will be published later in peer-reviewed journals (in addition to 61 articles already completed).

Report↗

USGS2019

Time-domain electromagnetic soundings for the delineation of saline groundwater in the Genesee River Valley, Western New York, 2016-2017

The U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, is investigating the distribution of saline groundwater in the Genesee River Valley near the former Retsof salt mine (fig. 1). As part of this study, paired time-domain electromagnetic (TEM) soundings and horizontal-to-vertical spectral ratio (HVSR) seismic soundings were made at 39 locations during the fall of 2016 to determine the presence of saline groundwater and depth to the bedrock surface, respectively. All measurement sites were west of Geneseo, New York, on the Genesee River valley floor north and south of the sinkhole area that developed as a result of the roof collapse and flooding of the Retsof mine in 1994 (fig. 1). An integrated analysis of the TEM and HVSR soundings with borehole logs, coupled with groundwater-sample data from previous investigations, allowed the delineation of zones of high electrical conductivity associated with saline water in the lower part of the valley fill and underlying bedrock to depths greater than 1,000 feet (ft). This article describes the TEM sounding method and its application in the ongoing investigation, presents results of the TEM analysis at two of the sounding sites, and identifies proposed sites for additional TEM/HVSR sounding data collection during the fall of 2017. Supporting data for this study are available in a separate data release (Johnson and others, 2017).

New York↗

USGS2019

Encylopedia of Caves

For many people, a visit to a cave is a wondrous event directing our minds to ponder the mysteries presented by these unique places and inspiring questions: How old is the cave? What was the role of water in forming the cave and where did the water come from? How is the cave connected to the surface environment? These are intriguing questions to ask, and karst scientists use isotope geochemistry to help solve these mysteries. Isotopes are atoms of the same chemical element that have the same number of protons but vary in their number of neutrons. As a result of their atomic mass difference, isotopes of a single element may exhibit slightly different chemical behavior. Radioisotopes are unstable and the nucleus of a parent isotope will spontaneously break apart (decay), releasing energy and changing into another element (daughter product) by loss or gain of protons, neutrons, or electrons. Stable isotopes, as implied by the name, are stable and do not spontaneously decay. These two types of isotopes are used widely by scientists to understand ancient and modern karst systems. Generally, radioisotopes are used for absolute dating karst water, cave sediments, cave formations (speleothems), and other material preserved in caves (such as bones). Stable isotopes can provide information about relative ages of cave water and speleothems. An absolute age provides a numeric date—such as 100,000 years old—whereas a relative age provides information that something is older or younger than something else—such as cave art is younger than a speleothem found in the same cave. Stable isotopes are used to study ancient karst systems because isotopic signals of past climate (paleoclimate) and environmental conditions (paleoenvironment) are preserved in speleothems and sediments. Stable isotopes are also used to understand modern systems, primarily through studies that distinguish sources of karst water, cave air, or contaminants, mixing of those sources, and biologic or chemical reactions that process compounds, such as breakdown of contaminants or organic matter. The variation in mass among isotopes is small, and isotope abundances are measured as a ratio of a common isotope to its less common isotopic counterparts (stable isotopes) or the abundance of a parent compared to daughter isotope (radioisotopes). As an example, hydrogen (H) has three naturally occurring isotopes. Most H comprises one proton (1H), but the rarer stable isotope (called deuterium) comprises one proton and one neutron (2H), and the radioisotope (called tritium) comprises one proton and two neutrons (3H). Because scientists use the minute differences in isotopes to test hypotheses, a scientist must understand the accuracy, precision, and error of the available methods, the assumptions about the chemical conditions of interest, and the limitations of the isotopic method being used. Many isotopic studies employ multiple isotopic tracers to better leverage the strengths and offset the limitations of using a single isotope. This article focuses on isotopes used to study the geology and hydrology of caves, but much additional isotopic work has been used to characterize the biology of caves.

Book chapter↗

USGS2019

Citing aquatic monitoring data sets: Best practice recommendations for authoritative data citation

The use of data generated from long term monitoring efforts necessitates accurate authoritative source citations of those data to ensure credit for data collected, and accountability for the data quality to enable repeated retrieval of a given data set. Data sets used in published reports and articles are increasingly being considered objects that are required to be published and cited. Aggregating data into open access databases is becoming common and is the focus of the Coordinated Assessment for Salmon and Steelhead project (CA; https://www.pnamp.org/project/coordinated-assessments-for-salmon-and-steelhead; http://www.streamnet.org/data/coordinated-assessments/ ) and National Marine Fisheries Service, National Oceanic and Atmospheric Administration Salmon Population Summary (SPS; https://www.webapps.nwfsc.noaa.gov/apex/f?p=261:home:0 ) among others. Guidelines are needed for citing these long-term dynamic data sets that have many contributors. We explore best practices and provide recommendations for including robust metadata attributes within data sets to enable data publication and citation using the CA and SPS data repositories as case studies. F rom reviewing the current citations possible from the CA and the SPS we recommend at minimum that natural resource monitoring databases contain: metadata to identify organizations that generated the data; contact persons for each organization that contributes data to an aggregated data set; and that metadata be incorporated into databases to enable auto-generated citations that recognize all contributing organizations with time-stamped versions of the data delivered. Beyond those minimums, additional best practice recommendations include this suite of metadata elements that identify a given data set upon citation or publication: author(s); publication date; description of data; file format(s) of data - e.g. tiles, shapefile sets, images, text files; dates data were collected; locations where data were collected; producers/contributors to the data set version cited; date data set was downloaded; original data repository from which the data were obtained; version identifier to note significant change to a data set; and a persistent identifier that can be used to locate that version of the data.

Report↗

USGS2004

Mitigation of earthquake damage

The article describes the use of a geologic map to help mitigate earthquake damage along the Denali Fault where the Trans-Alaska Pipeline crosses. Geologic mapping of bedrock and unconsolidated deposits reveals a history of horizontal right-lateral slip and local vertical separations at the fault. It was determined that the eastern 220 mile of the Denali and Totschunda fault system was the most likely segment to generate an 8+ magnitude earthquake.

Alaska↗

USGS1990

Prevalence and characteristics of plastic ingested by Hawaiian seabirds

The prevalence of plastic in 18 species of seabirds at seven study sites in the Hawaiian Islands and Johnston Atoll was studied during 1986 and 1987. Stomach samples were collected by induced emesis from 1,803 live birds of 15 species and during necropsy of 277 dead birds of 5 species. The prevalence of ingested plastic varied greatly among species; age, year of collection, and location of the study site had less pronounced but significant effects. Ingested plastic was absent or uncommon in terns and noddies. Plastic was not found at all in samples from gray-backed terns, Sterna lunata , or white terns, Gygis alba . The prevalence was low in sooty terns, Sterna fuscata (0 to 8%), and brown, Anous stolidus , and black noddies, A. minutus (0 to 3%). Plastic was much more prevalent (67 to 100%) in chicks of black-footed, Diomedea nigripes , and Laysan albatrosses, D. immutabilis . In the 11 other species prevalence ranged from 0 to 44% depending on the age, year of collection, and location. The mean volume of plastic in samples collected at necropsy from Laysan albatross chicks was higher in 1986 (46 cc) than in 1987 (5 cc). Prevalence was generally higher in seabirds which fed at the surface. Fragments of manufactured articles were the most common type of plastic found. Other plastics included pellets, Styrofoam, bottle caps, bags, and sponges. The largest individual item (200 cc) and the greatest diversity of plastic items were found in albatross chicks.

Hawaii↗

USGS2021

Mesozoic magmatism in Montana

From crystalline batholiths with footprints larger than 4,500 km 2 to beds of micron-sized ash particles, a record of Mesozoic magmatism is found throughout Montana. Mesozoic igneous rocks are an important natural resource in the state because of their association with precious metal ores and industrial mineral deposits. Mesozoic magmatism in Montana is a tale of volcanic arc eruptions, pluton emplacement, crustal magma differentiation, melting, and assimilation. Explosive caldera-forming eruptions, magmatic hydrothermal and metamorphic mineralization, tectonic uplift, fluvial erosion, and redeposition of igneous rocks and mineral resources are all chronicled by Mesozoic igneous rocks. This article offers a summary of the types, locations, extents, and ages of Mesozoic igneous rocks in Montana. Then follows a discussion of the generation and emplacement of magmas and intrusive rocks, their geometries, and the style and timing of magmatism. The chapter ends with a summary of what remains unknown and offers suggestions for future research.

Montana↗

USGS2019

The US Geological Survey’s Earth Mapping Resources Initiative (Earth MRI)—Providing framework geologic, geophysical, and elevation data to the nation’s critical mineral-bearing regions

New detailed mapping of the geologic resources of the Nation has the potential to significantly close the gap in the essential data needed to fuel a modern era of economic development and technological innovation, while at the same time dramatically enhancing our understanding of the fundamental way geology impacts everyday life, from the domestic critical mineral resources that are necessary for modern technology and the economy, to domestic energy and water resources, geologic hazards, agriculture, and other pressing needs. The U.S. Geological Survey established the Earth Resources Mapping Initiative (Earth MRI) to address the shortfall in geologic, geophysical, and elevation data with sufficient detail to support evaluation of regions in the United States that have potential to host critical mineral resources. The new effort is a collaboration with the Association of American State Geologists, who are providing new detailed geologic maps and making available online archived data and information related to critical mineral resources. The geophysical and lidar surveys are being contracted through industry specialists to assure that high-quality data are available to the public. This article provides an overview of the Earth MRI effort with discussions on the initial geophysical surveys funded for areas that have known potential for rare earth element resources. Subsequent projects are being designed to address areas that may host other critical mineral resources.

Fast Times↗

USGS2021

Genetics as a tool for conservation and management of West Indian manatee populations in Brazil

A study conducted by the National Center for Research and Conservation of Aquatic Mammals (CMA), United States Geological Survey Wetland and Aquatic Research Center, and partner researchers found that the marine Antillean manatee ( Trichechus manatus manatus ) has low genetic diversity in regions where there are territorial interfaces with the Amazonian manatee ( Trichechus inunguis ). The study was published as an article in the journal, Frontiers in Marine Science.

Sirenews↗

USGS2021

Identifying the ecological and management implications of mangrove migration in the northern Gulf of Mexico

Climate change is transforming ecosystems and affecting ecosystem goods and services. Along the Gulf of Mexico and Atlantic coasts of the southeastern United States, the frequency and intensity of extreme freeze events greatly influences whether coastal wetlands are dominated by freeze-sensitive woody plants (mangrove forests) or freeze-tolerant grass-like plants (salt marshes). In response to warming winters, mangroves have been expanding and displacing salt marshes at varying degrees of severity in parts of north Florida, Louisiana, and Texas. As winter warming accelerates, mangrove range expansion is expected to increasingly modify wetland ecosystem structure and function. Because there are differences in the ecological and societal benefits that salt marshes and mangroves provide, coastal environmental managers are challenged to anticipate effects of mangrove expansion on critical wetland ecosystem services, including those related to carbon sequestration, wildlife habitat, storm protection, erosion reduction, water purification, fisheries support, and recreation. This project produced information that is relevant to scientists and coastal resource managers working within the transition zone between mangrove forests and salt marshes. The two primary products are: (1) an investigation that leverages data and information from a community-curated data network called the Mangrove Migration Network to refine temperature thresholds for mangrove range expansion in a warming climate; and (2) a review article that examines current understanding of the effects of mangrove range expansion and displacement of salt marshes on wetland ecosystem services, including those related to carbon sequestration, wildlife habitat, storm protection, erosion reduction, water purification, fisheries support, and recreation.

Alabama, Florida, Louisiana, Mississippi, Texas↗

USGS1912

Report of the Hawaiian Volcano Observatory of the Massachusetts Institute of Technology and the Hawaiian Volcano Research Association

The First Report of the Hawaiian Volcano Observatory is a collection of nine papers. The first provides details of the founding of the Observatory and the second reviews Kīlauea volcanic activity between 1909 and 1911. The next two papers detail the work of the Observatory by Frank Perret and E.S. Shepherd, who both arrived at Kīlauea in the summer of 1911. The third paper focuses on Perret's observations of the eruption within Halema'uma'u, a crater within Kīlauea summit caldera, and includes six weekly articles he wrote for local newspapers. The fourth paper is an account of the first successful attempt to measure the temperature of lava in Halema'uma'u. The next three papers are summaries of Halema'uma'u activity spanning the time after Frank Perret left in the Fall of 1911 to April 3, 1912. The last two papers are brief reports on Mauna Loa.

Report of the Hawaiian Volcano Observatory↗