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USGS2009

Velocity mapping in the Lower Congo River: A first look at the unique bathymetry and hydrodynamics of Bulu Reach

The lower Congo River is one of the deepest, most powerful, and most biologically diverse stretches of river on Earth. The river’s 270 m decent from Malebo Pool though the gorges of the Crystal Mountains to the Atlantic Ocean (498 km downstream) is riddled with rapids, cataracts, and deep pools. Much of the lower Congo is a mystery from a hydraulics perspective. However, this stretch of the river is a hotbed for biologists who are documenting evolution in action within the diverse, but isolated, fish populations. Biologists theorize that isolation of fish populations within the lower Congo is due to barriers presented by flow structure and bathymetry. To investigate this theory, scientists from the U.S. Geological Survey and American Museum of Natural History teamed up with an expedition crew from National Geographic in 2008 to map flow velocity and bathymetry within target reaches in the lower Congo River using acoustic Doppler current profilers (ADCPs) and echo sounders. Simultaneous biological and water quality sampling was also completed. This paper presents some preliminary results from this expedition, specifically with regard to the velocity structure andbathymetry. Results show that the flow in the bedrock controlled Bulu reach of the lower Congo is highly energetic. Turbulent and secondary flow structures can span the full depth of flow (up to 165 m), while coherent bank-to-bank cross-channel flow structures are absent. Regions of flow separation near the banks are isolated from one another and from the opposite bank by high shear, high velocity zones with depth-averaged flow velocities that can exceed 4 m/s.

Lower Congo River↗

USGS1994

Verification of a national water data base using a geographic information system

The National Water Data Exchange (NAWDEX) was developed to assist users of water-resource data in the identification, location, and acquisition of data. The Master Water Data Index (MWDI) of NAWDEX currently indexes the data collected by 423 organizations from nearly 500,000 sites throughout the United Stales. The utilization of new computer technologies permit the distribution of the MWDI to the public on compact disc. In addition, geographic information systems (GIS) are now available that can store and analyze these data in a spatial format. These recent innovations could increase access and add new capabilities to the MWDI. Before either of these technologies could be employed, however, a quality-assurance check of the MWDI needed to be performed. The MWDI resides on a mainframe computer in a tabular format. It was copied onto a workstation and converted to a GIS format. The GIS was used to identify errors in the MWDI and produce reports that summarized these errors. The summary reports were sent to the responsible contributing agencies along with instructions for submitting their corrections to the NAWDEX Program Office. The MWDI administrator received reports that summarized all of the errors identified. Of the 494,997 sites checked, 93,440 sites had at least one error (18.9 percent error rate).

Open-File Report↗

USGS2000

Geographic Information for Analysis of Highway Runoff-Quality Data on a National or Regional Scale in the Conterminous United States

Spatial data are important for interpretation of water-quality information on a regional or national scale. Geographic information systems (GIS) facilitate interpretation and integration of spatial data. The geographic information and data compiled for the conterminous United States during the National Highway Runoff Water-Quality Data and Methodology Synthesis project is described in this document, which also includes information on the structure, file types, and the geographic information in the data files. This 'geodata' directory contains two subdirectories, labeled 'gisdata' and 'gisimage.' The 'gisdata' directory contains ArcInfo coverages, ArcInfo export files, shapefiles (used in ArcView), Spatial Data Transfer Standard Topological Vector Profile format files, and meta files in subdirectories organized by file type. The 'gisimage' directory contains the GIS data in common image-file formats. The spatial geodata includes two rain-zone region maps and a map of national ecosystems originally published by the U.S. Environmental Protection Agency; regional estimates of mean annual streamflow, and water hardness published by the Federal Highway Administration; and mean monthly temperature, mean annual precipitation, and mean monthly snowfall modified from data published by the National Climatic Data Center and made available to the public by the Oregon Climate Service at Oregon State University. These GIS files were compiled for qualitative spatial analysis of available data on a national and(or) regional scale and therefore should be considered as qualitative representations, not precise geographic location information.

Open-File Report↗

USGS1991

National aerial photography program as a geographic information system resource

The National Aerial Photography Program (NAPP) is jointly funded by Federal agencies and States that choose to participate in a 50-50 cost sharing cooperative arrangement. The NAPP is designed to acquire black-and-white (B&W) or color infrared (CIR) photography at a scale of 1:40,000. The status of NAPP flying, now going into the first year of its second 5-year cycle, is reviewed to inform the user community of NAPP's coverage. The resolution, geometric quality and flight parameters are used to estimate the system's cartographic potential to produce orthophotoquads, digital elevation models, topographic maps and digital information to meet national map accuracy standards at 1:12,000 and 1:24,000-scale and serve as a geographic information system resource. Also, a technique is presented to compute the optimum scanning spot size (15 ??m) and storage required for converting the B&W or CIR photography to digital, machine-readable pixel form. The resulting digital NAPP data are suitable for a wide variety of new applications, including use in geographic information systems.

Conference Paper↗

USGS2012

Structures data collection for the national map using volunteered geographic information

The U.S. Geological Survey (USGS) has historically sponsored volunteered data collection projects to enhance its topographic paper and digital map products. This report describes one phase of an ongoing project to encourage volunteers to contribute data to The National Map using online editing tools. The USGS recruited students studying geographic information systems (GIS) at the University of Colorado Denver and the University of Denver in the spring of 2011 to add data on structures - manmade features such as schools, hospitals, and libraries - to four quadrangles covering metropolitan Denver. The USGS customized a version of the online Potlatch editor created by the OpenStreetMap project and populated it with 30 structure types drawn from the Geographic Names Information System (GNIS), a USGS database of geographic features. The students corrected the location and attributes of these points and added information on structures that were missing. There were two rounds of quality control. Student volunteers reviewed each point, and an in-house review of each point by the USGS followed. Nine-hundred and thirty-eight structure points were initially downloaded from the USGS database. Editing and quality control resulted in 1,214 structure points that were subsequently added to The National Map . A post-project analysis of the data shows that after student edit and peer review, 92 percent of the points contributed by volunteers met National Map Accuracy Standards for horizontal accuracy. Lessons from this project will be applied to later phases. These include: simplifying editing tasks and the user interfaces, stressing to volunteers the importance of adding structures that are missing, and emphasizing the importance of conforming to editorial guidelines for formatting names and addresses of structures. The next phase of the project will encompass the entire State of Colorado and will allow any citizen to contribute structures data. Volunteers will benefit from this project by engaging with their local geography and contributing to a national resource of topographic information that remains in the public domain for anyone to download.

Denver↗

USGS2013

Tidal wetlands of the Yaquina and Alsea River estuaries, Oregon: Geographic Information Systems layer development and recommendations for National Wetlands Inventory revisions

Geographic Information Systems (GIS) layers of current, and likely former, tidal wetlands in two Oregon estuaries were generated by enhancing the 2010 National Wetlands Inventory (NWI) data with expert local field knowledge, Light Detection and Ranging-derived elevations, and 2009 aerial orthophotographs. Data were generated for two purposes: First, to enhance the NWI by recommending revised Cowardin classifications for certain NWI wetlands within the study area; and second, to generate GIS data for the 1999 Yaquina and Alsea River Basins Estuarine Wetland Site Prioritization study. Two sets of GIS products were generated: (1) enhanced NWI shapefiles; and (2) shapefiles of prioritization sites. The enhanced NWI shapefiles contain recommended changes to the Cowardin classification (system, subsystem, class, and/or modifiers) for 286 NWI polygons in the Yaquina estuary (1,133 acres) and 83 NWI polygons in the Alsea estuary (322 acres). These enhanced NWI shapefiles also identify likely former tidal wetlands that are classified as upland in the current NWI (64 NWI polygons totaling 441 acres in the Yaquina estuary; 16 NWI polygons totaling 51 acres in the Alsea estuary). The former tidal wetlands were identified to assist strategic planning for tidal wetland restoration. Cowardin classifications for the former tidal wetlands were not provided, because their current hydrology is complex owing to dikes, tide gates, and drainage ditches. The scope of this project did not include the field evaluation that would be needed to determine whether the former tidal wetlands are currently wetlands, and if so, determine their correct Cowardin classification. The prioritization site shapefiles contain 49 prioritization sites totaling 2,177 acres in the Yaquina estuary, and 39 prioritization sites totaling 1,045 acres in the Alsea estuary. The prioritization sites include current and former (for example, diked) tidal wetlands, and provide landscape units appropriate for basin-scale wetland restoration and conservation action planning. Several new prioritization sites (not included in the 1999 prioritization) were identified in each estuary, consisting of NWI polygons formerly classified as nontidal wetland or upland. The GIS products of this project improve the accuracy and utility of the NWI data, and provide useful tools for estuarine resource management.

Oregon↗

USGS2012

The 3D Elevation Program: summary of program direction

The 3D Elevation Program (3DEP) initiative responds to a growing need for high-quality topographic data and a wide range of other three-dimensional representations of the Nation's natural and constructed features. The National Enhanced Elevation Assessment (NEEA), which was completed in 2011, clearly documented this need within government and industry sectors. The results of the NEEA indicated that enhanced elevation data have the potential to generate $13 billion in new benefits annually. The benefits apply to food risk management, agriculture, water supply, homeland security, renewable energy, aviation safety, and other areas. The 3DEP initiative was recommended by the National Digital Elevation Program and its 12 Federal member agencies and was endorsed by the National States Geographic Information Council (NSGIC) and the National Geospatial Advisory Committee (NGAC).

Fact Sheet↗

USGS2004

The National Atlas of the United States now on the Web and in print

The National Atlas of the United States of America ® was published in 1970 as a book, with more than 400 pages and 765 maps. Since then, many people have called for a new edition, and many maps have been published as single sheets using the classic National Atlas 1:7,500,000-scale format. Work began in 1997 on a new, web-based edition of the National Atlas of the United States ® . Accessible at http://nationalatlas.gov, the new atlas features an interactive mapmaker with more than 1,000 data layers. Developed as a coordinated package of dynamic webbased map products and services, and printed and printable maps for selected themes, the National Atlas of the United States of America ® has grown beyond a book. Yet, the cartographer’s fundamental job remains the same as it was in 1970—to translate national-level geographic data into an understandable view of the nation.

ACSM Bulletin↗

USGS2009

A national look at carbon capture and storage-National carbon sequestration database and geographical information system (NatCarb)

The US Department of Energy's Regional Carbon Sequestration Partnerships (RCSPs) are responsible for generating geospatial data for the maps displayed in the Carbon Sequestration Atlas of the United States and Canada. Key geospatial data (carbon sources, potential storage sites, transportation, land use, etc.) are required for the Atlas, and for efficient implementation of carbon sequestration on a national and regional scale. The National Carbon Sequestration Database and Geographical Information System (NatCarb) is a relational database and geographic information system (GIS) that integrates carbon storage data generated and maintained by the RCSPs and various other sources. The purpose of NatCarb is to provide a national view of the carbon capture and storage potential in the U.S. and Canada. The digital spatial database allows users to estimate the amount of CO 2 emitted by sources (such as power plants, refineries and other fossil-fuel-consuming industries) in relation to geologic formations that can provide safe, secure storage sites over long periods of time. The NatCarb project is working to provide all stakeholders with improved online tools for the display and analysis of CO 2 carbon capture and storage data. NatCarb is organizing and enhancing the critical information about CO 2 sources and developing the technology needed to access, query, model, analyze, display, and distribute natural resource data related to carbon management. Data are generated, maintained and enhanced locally at the RCSP level, or at specialized data warehouses, and assembled, accessed, and analyzed in real-time through a single geoportal. NatCarb is a functional demonstration of distributed data-management systems that cross the boundaries between institutions and geographic areas. It forms the first step toward a functioning National Carbon Cyberinfrastructure (NCCI). NatCarb provides access to first-order information to evaluate the costs, economic potential and societal issues of CO 2 capture and storage, including public perception and regulatory aspects. NatCarb online access has been modified to address the broad needs of a spectrum of users. NatCarb includes not only GIS and database query tools for high-end user, but simplified display for the general public using readily available web tools such as Google Earth???and Google Maps???. Not only is NatCarb connected to all the RCSPs, but data are also pulled from public servers including the U.S. Geological Survey-EROS Data Center and from the Geography Network. Data for major CO 2 sources have been obtained from U.S. Environmental Protection Agency (EPA) databases, and data on major coal basins and coalbed methane wells were obtained from the Energy Information Administration (EIA). ?? 2009 Elsevier Ltd. All rights reserved.

Conference Paper↗

USGS2014

Proceedings of the U.S. Geological Survey Eighth Biennial Geographic Information Science Workshop and first The National Map Users Conference, Denver, Colorado, May 10-13, 2011

The U.S. Geological Survey (USGS) is sponsoring the first The National Map Users Conference in conjunction with the eighth biennial Geographic Information Science (GIS) Workshop on May 10-13, 2011, in Lakewood, Colorado. The GIS Workshop will be held at the USGS National Training Center, located on the Denver Federal Center, Lakewood, Colorado, May 10-11. The National Map Users Conference will be held directly after the GIS Workshop at the Denver Marriott West, a convention hotel in the Lakewood, Colorado area, May 12-13. The National Map is designed to serve the Nation by providing geographic data and knowledge for government, industry, and public uses. The goal of The National Map Users Conference is to enhance communications and collaboration among the communities of users of and contributors to The National Map, including USGS, Department of the Interior, and other government GIS specialists and scientists, as well as the broader geospatial community. The USGS National Geospatial Program intends the conference to serve as a forum to engage users and more fully discover and meet their needs for the products and services of The National Map. The goal of the GIS Workshop is to promote advancement of GIS and related technologies and concepts as well as the sharing of GIS knowledge within the USGS GIS community. This collaborative opportunity for multi-disciplinary GIS and associated professionals will allow attendees to present and discuss a wide variety of geospatial-related topics. The Users Conference and Workshop collaboration will bring together scientists, managers, and data users who, through presentations, posters, seminars, workshops, and informal gatherings, will share accomplishments and progress on a variety of geospatial topics. During this joint event, attendees will have the opportunity to present or demonstrate their work; to develop their knowledge by attending hands-on workshops, seminars, and presentations given by professionals from USGS and other Federal Agencies, GIS related companies, and academia; and to network with other professionals to develop collaborative opportunities. Specific conference topics include scientific and modeling applications using The National Map, opportunities for partnerships, and advances in geospatial technologies. The first part of the week will be the GIS Workshop, offered as a pre-conference seminar. It will focus on hands-on GIS training and seminars concerning current topics of geospatial interest. The focus of the USGS GIS Workshop is to showcase specific techniques and concepts for using GIS in support of science. The presentations will be educational and not a marketing endeavor. To promote awareness of and interaction with selected USGS corporate and local science center data products, as well as promoting collaboration, a “GIS Olympics” event will be held Tuesday evening during the GIS Workshop. The second part of the week will feature interactive briefings and discussions on issues and opportunities of The National Map. The focus of the Users Conference will be on the role of The National Map in supporting science initiatives, emergency response, land and wildlife management, and other activities. All presentations at the Users Conference include use or innovations related to a The National Map data theme or application. On Wednesday evening, a poster session is being held as a combined event for all attendees and as a juncture between the events. On Thursday evening, the Henry Gannett Award will be presented. Additionally, poster awards will be presented. Several prominent speakers are featured at plenary sessions at The National Map Users Conference, including Deanna A. Archuleta, Deputy Assistant Secretary for Water and Science, Department of the Interior; Dr. Barbara P. Buttenfield, Professor of Geography at the University of Colorado in Boulder; best-selling author Frederick Reuss; and Dr. Joel Scheraga, Senior Advisor for Climate Adaptation, U.S. Environmental Protection Agency. Additionally, panel discussions have attracted participation from notable experts from government, academia, and the private sector. This Proceedings volume will serve as an activity reference for workshop attendees, as well as an archive of technical abstracts presented at the workshop. Author, co-author, and presenter names, affiliations, and contact information are listed with presentation titles with the abstracts. Some hands-on sessions are offered twice; in these instances, abstracts submitted for publication are presented in the proceedings on both days on which they are offered.

Scientific Investigations Report↗

USGS2019

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

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

Natural Resource Report↗

USGS2015

U.S. Geological Survey National Water Census: Colorado River Basin Geographic Focus Area Study

Introduction The U.S. Geological Survey’s (USGS) concept of a national census (or accounting) of water resources has evolved over the last several decades as the Nation has experienced increasing concern over water availability for multiple competing uses. The implementation of a USGS National Water Census was described in the USGS 2007 science strategy document that identified the highest priority science topics for the decade 2007–17. In 2009, the SECURE Water Act (Public Law 111–11, subtitle F) authorized the USGS to create a Water Availability and Use Assessment Program for the Nation, and in 2012, the Department of the Interior WaterSMART initiative provided funding to begin implementation of the USGS National Water Census (NWC). Generally, the USGS NWC approaches water-availability assessment in terms of a “water budget.” The water-budget approach seeks to better quantify the inflows and outflows of water, as well as the change in storage volume, both nationally and at a regional scale and, by doing so, provides critical information to managers and stakeholders responsible for making water-availability decisions. The NWC has two primary components: Topical Studies and Geographic Focus Area Studies. Topical Studies do research on methods that can provide nationwide estimates of particular water-budget components at the subwatershed scale. Some examples of NWC Topical Studies include estimation of streamflow at ungaged locations; periodic quantification of evapotranspiration; and water use related to development of unconventional oil and gas. These efforts are planned to include additional topics in the future. Geographic Focus Area Studies (FASs) assess water availability and use within a defined geographic area, typically a surface-water drainage basin, to increase the understanding of factors affecting water availability in the region. In the FASs, local stakeholder input helps the USGS identify what components of the water budget are in most need of additional understanding or quantification. Focus Area Studies are planned as 3-year efforts and, typically, three FASs are ongoing in different parts of the country at any given time. The Colorado River Basin (CRB) and the Delaware and Apalachicola-Chattahoochee-Flint (ACF) River Basins were selected by the Department of the Interior for the first round of FASs because of the perceived water shortages in the basins and potential conflicts over water supply and allocations. After gathering input from numerous stakeholders in the CRB, the USGS determined that surface-water resources in the basin were already being closely monitored and that the most important scientific contribution could be made by helping to improve estimates of four water-budget components: evapotranspiration losses, snowpack hydrodynamics, water-use information, and the relative importance of groundwater discharge in supporting streamflow across the basin. The purpose of this fact sheet is to provide a brief summary of the CRB FAS results as the study nears completion. Although some project results are still in the later stages of review and publication, this fact sheet provides an overall description of the work completed and cites the publications in which additional information can be found.

Arizona, California, Colorado, Nevada, New Mexico,↗

USGS1997

Water-quality assessment of the Las Vegas Valley area and the Carson and Truckee River basins, Nevada and California: Nutrients, pesticides, and suspended sediment, October 1969-April 1990

The U.S. Geological Survey National Water-Quality Assessment Program (NAWQA) is designed to provide long-term, consistent information on water quality that can be used to describe local, regional, and national conditions. The full-scale NAWQA Program, initiated in 1991, includes both study-unit and national synthesis activities. Study-unit investigations provide scientific data and interpretations that will be integrated by national synthesis studies to assess the quality of the Nation's water resources. The Nevada Basin and Range (NVBR) study unit is one of 60 proposed NAWQA study units in the United States. These riverbasin-scale areas were selected to represent large proportions of the Nation's water use and population served by public supplies, and the Nation's geographic diversity. The NVBR study unit includes the Las Vegas Valley area, approximately 1,640 mi in southern Nevada, and the Carson River Basin (3,970 mi 2 ) and Truckee River Basin (3,230 mi 2 ) in northwestern Nevada and northeastern California. The areas are typical of Basin and Range physiography. Snowfall in high mountains provides streamflow and ground-water recharge in adjacent basins. Unconsolidated basin-fill deposits commonly exceed 1,000 ft in thickness and are principal aquifers in the study unit. The study-unit climate varies from humid continental in the Sierra Nevada where the Carson and Truckee Rivers originate (annual precipitation exceeds 30 in.) to desert in terminal parts of the basins, including the Carson Desert and lower altitudes in Las Vegas Valley, where annual precipitation is less than 5 in. In 1990, Nevada had the greatest population growth rate and the fourth greatest percentage of population residing in urban areas in the Nation. More than 90 percent of Nevada's population (about 1,090,000 in 1990) resided in the study unit; the Las Vegas Valley area (about 710,000) was the most populous area. In 1990, water use in the study unit was about 1,117,000 acre-ft. Water use in the Las Vegas Valley area was about 317,000 acre-ft; 91 percent was for public supplies. Las Vegas Valley was 79 percent range land, but the 5 percent urban land use has significantly affected water resources. Water use in the Carson River Basin was 538,000 acre-ft in 1990. About 95 percent of the water was used for irrigation, although only 5 percent of the land was used for irrigated agriculture. Water use in the Truckee River Basin was 262,000 acre-ft in 1990. Public supply used about 36 percent of the water, although only 3 percent of the land was urban. Nutrients, pesticides, and suspended sediments are important water-quality issues in the study unit. Urban runoff and treated sewage effluent contribute these constituents to Las Vegas Wash and the Truckee River. Urban and agricultural activities in the Carson and Truckee River Basins are also sources of these constituents.

California, Nevada↗

USGS2003

Native weeds and exotic plants: Relationships to disturbance in mixed-grass prairie

Disturbance frequently is implicated in the spread of invasive exotic plants. Disturbances may be broadly categorized as endogenous (e.g., digging by fossorial animals) or exogenous (e.g., construction and maintenance of roads and trails), just as weedy species may be native or exotic in origin. The objective of this study was to characterize and compare exotic and native weedy plant occurrence in and near three classes of disturbance -digging by prairie dogs (an endogenous disturbance to which native plants have had the opportunity to adapt), paved or gravel roads (an exogenous disturbance without natural precedent), and constructed trails (an exogenous disturbance with a natural precedent in trails created by movement of large mammals) - in three geographically separate national park units. I used plant survey data from the North and South Units of Theodore Roosevelt National Park and Wind Cave National Park in the northern mixed-grass prairie of western North and South Dakota, USA, to characterize the distribution of weedy native and exotic plants with respect to the three disturbance classes as well as areas adjacent to them. There were differences both in the susceptibility of the disturbance classes to invasion and in the distributions of native weeds and exotic species among the disturbance classes. Both exotic and native weedy species richness were greatest in prairie dog towns and community composition there differed most from undisturbed areas. Exotic species were more likely to thrive near roadways, where native weedy species were infrequently encountered. Exotic species were more likely to have spread beyond the disturbed areas into native prairie than were weedy native species. The response of individual exotic plant species to the three types of disturbance was less consistent than that of native weedy species across the three park units.

Plant Ecology↗

USGS2014

Report of Committee on Runoff, 1942–43

The Committee on Runoff was not formally constituted until February 6, 1943, when the members of the Section, as listed above, were asked to serve. At the suggestion of President CHURCH the Committee has been so selected that there is Nation‐wide geographic distribution from West to East with the majority of the Committee composed of younger men. If the 33 papers prepared for discussion at the regular sessions of the Section of Hydrology at the annual meeting of 1943 can be used as a measure, war instead of curtailing the activities of the Section has acted as an impetus. Also in the field of hydrology as a whole, war activities have apparently not resulted in a decrease of activities. There has been, however, a gradual decrease of activities in the field of research and an increase of activities in the field of applied hydrology. The enormous expansion of our industrial machine and the great concentration of armies and industrial workers into restricted areas; the demands for water, for power, for food and for municipal use; and operations underlying many of our war efforts, secret and otherwise—all these have created problems requiring the full‐time effort of hydrologists, both in private and governmental service. It is with some degree of satisfaction that each one of us can feel that either as a result of our past research or in our present positions we have been or are doing our bit to win the war.

Eos, Transactions, American Geophysical Union↗

USGS1991

Visual geography

Maps are, among other things, a way of making geography visual. They are world views, ways of thinking, and ways of communicating. They depict our world and guide us through it. Visual Geography probes the essence of maps and mapmaking. It follows the story of cartography through the millennia, across the globe, and beyond the solar system. It includes some of the world's most beautiful and enduring maps, some of its most historic - a map in Columbus' hand, the map that was carried to the Moon, the first map to show America - and it examines the urge to map, to measure our world, and to record it graphically.

General Information Product↗

USGS2001

The National Petroleum Reserve-Alaska (NPRA) data archive

The area currently known as the National Petroleum ReserveAlaska was originally designated in 1923 as Naval Petroleum Reserve No. 4 (NPR4). It was one of four U.S. regions thought to contain significant amounts of oil that were to be reserved for national crises. Geographic and geologic knowledge of the NPR4 was only superficial in 1923. Earlier exploration, however, had shown that the region contained the ingredients necessary for oil accumulations to exist: source rocks, reservoir rocks, and geologic structures that could trap petroleum. Oil seeps on the coast and the size of the area (some 37,000 square miles, about the size of Indiana) reinforced the notion that significant quantities of petroleum were present.

Fact Sheet↗

USGS2009

Evaluation of hazardous faults in the intermountain west region: Summary and recommendations of a workshop

The U.S. Geological Survey’s (USGS) Earthquake Hazards Program (EHP) has the responsibility to provide nationwide information and knowledge about earthquakes and earthquake hazards as a step to mitigating earthquake-related losses. As part of this mission, USGS geologists and geophysicists continue to study faults and structures that have the potential to generate large and damaging earthquakes. In addition, the EHP, through its External Grants Program (hereinafter called Program), supports similar studies by scientists employed by state agencies, academic institutions, and independent employers. For the purposes of earthquake hazard investigations, the Nation is geographically subdivided into tectonic regions. One such region is the Intermountain West (IMW), which here is broadly defined as starting at the eastern margin of the Rocky Mountains in New Mexico, Colorado, Wyoming, and Montana and extending westward to the east side of the Sierra Nevada mountains in eastern California and into the Basin and Range-High Plateaus of eastern Oregon and Washington. The IMW contains thousands of faults that have moved in Cenozoic time, hundreds of which have evidence of Quaternary movement, and thus are considered to be potential seismic sources. Ideally, each Quaternary fault should be studied in detail to evaluate its rate of activity in order to model the hazard it poses. The study of a single fault requires a major commitment of time and resources, and given the large number of IMW faults that ideally should be studied, it is impractical to expect that all IMW Quaternary faults can be fully evaluated in detail. A more realistic approach is to prioritize a list of IMW structures that potentially pose a significant hazard and to focus future studies on those structures. Accordingly, in June 2008, a two-day workshop was convened at the USGS offices in Golden, Colorado, to seek information from representatives of selected State Geological Surveys in the IMW and with knowledgeable regional experts to identify the important structures for future studies. Such a priority list allows Program managers to guide the limited resources toward studies of features that are deemed to potentially pose the most serious hazards in the IMW. It also provides the scientific community with a list of structures to investigate because they are deemed to pose a substantial hazard to population centers or critical structures. The IMW encompasses all or large parts of 12 states, including Arizona, New Mexico, extreme west Texas, Colorado, Utah, Nevada, eastern California, eastern Oregon, eastern Washington, Idaho, western Wyoming, and western Montana. In Utah, and more recently in Nevada, geoscientists have taken steps to evaluate geologic data related to well-studied faults and to develop a statewide priority list of hazardous structures. In contrast to Utah and Nevada, the other IMW states contain substantially fewer Quaternary faults, so there have not been any previous efforts to develop similar priority lists. This workshop was organized to address this matter and create a more balanced perspective of priorities throughout the entire IMW region. Because working groups and workshops had already been convened to specifically deal with Quaternary fault priorities in Utah and Nevada, this workshop specifically emphasized structures outside of these two states.

Arizona, California, Colorado, Idaho, Montana, Nev↗