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USGS2004

The Colorado Plateau: cultural, biological, and physical research

Stretching from the four corners of Arizona, New Mexico, Colorado, and Utah, the Colorado Plateau is a natural laboratory for a wide range of studies. This volume presents 23 original articles drawn from more than 100 research projects presented at the Sixth Biennial Conference of Research on the Colorado Plateau. This scientific gathering revolved around research, inventory, and monitoring of lands in the region. The book's contents cover management techniques for cultural, biological, and physical resources, representing collaborative efforts among federal, university, and private sector scientists and land managers. Chapters on cultural concerns cover benchmarks of modern southwestern anthropological knowledge, models of past human activity and impact of modern visitation at newly established national monuments, challenges in implementing the 1964 Wilderness Act, and opportunities for increased federal research on Native American lands. The section on biological resources comprises sixteen chapters, with coverage that ranges from mammalian biogeography to responses of elk at the urban-wildland interface. Additional biological studies include the effects of fire and grazing on vegetation; research on bald eagles at Grand Canyon and tracking wild turkeys using radio collars; and management of palentological resources. Two final chapters on physical resources consider a proposed rerouting of the Rio de Flag River in urban Flagstaff, Arizona, and an examination of past climate patterns over the Plateau, using stream flow records and tree ring data. In light of similarities in habitat and climate across the Colorado Plateau, techniques useful to particular management units have been found to be applicable in many locations. This volume highlights an abundance of research that will prove useful for all of those working in the region, as well as for others seeking comparative studies that integrate research into land management actions.

Utah;Colorado;Arizona;New Mexico↗

USGS2018

How hydrologic connectivity regulates water quality in river corridors

Downstream flow in rivers is repeatedly delayed by hydrologic exchange with off‐channel storage zones where biogeochemical processing occurs. We present a dimensionless metric that quantifies river connectivity as the balance between downstream flow and the exchange of water with the bed, banks, and floodplains. The degree of connectivity directly influences downstream water quality — too little connectivity limits the amount of river water exchanged and leads to biogeochemically inactive water storage, while too much connectivity limits the contact time with sediments for reactions to proceed. Using a metric of reaction significance based on river connectivity, we provide evidence that intermediate levels of connectivity, rather than the highest or lowest levels, are the most efficient in removing nitrogen from Northeastern United States’ rivers. Intermediate connectivity balances the frequency, residence time, and contact volume with reactive sediments, which can maximize the reactive processing of dissolved contaminants and the protection of downstream water quality. Our simulations suggest denitrification dominantly occurs in riverbed hyporheic zones of streams and small rivers, whereas vertical turbulent mixing in contact with sediments dominates in mid‐size to large rivers. The metrics of connectivity and reaction significance presented here can facilitate scientifically based prioritizations of river management strategies to protect the values and functions of river corridors.

Journal of the American Water Resources Associatio↗

USGS2011

The United Nations framework classification for fossil energy and mineral reserves and resources 2009

Effective resource management in a globalizing economy requires accurate assessments of fossil energy and minerals resources. The recoverable quantities must be described and categorized in a manner that is consistent with scientific and social/economic information describing the economy as well as with the information describing the projects to recover them. A number of different standards have evolved over time in response to various professional needs Under a mandate given by the United Nations Economic and Social Council, the United Nations Economic Commission for Europe (UNECE) has cooperated with Governments, regulatory agencies, industry, international organizations, and professional organizations (including Committee for Mineral Reserves International Reporting Standards (CRIRSCO), the Society of Petroleum Engineers (SPE), the American Association of Petroleum Geologists (AAPG), and the Society of Petroleum Evaluation Engineers (SPEE)), as well as with outstanding experts, to define a global classification for extractive activities (including oil, gas, heavy oil and bitumen extraction) that reflects the principal concerns of existing petroleum and mineral classifications. The United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources-2009 (UNFC-2009) aims to serve the following four principal needs: 1. The needs in international energy and mineral studies to formulate robust and long-sighted policies. 2. The needs of governments in managing their resources accordingly, allowing market prices to be transferred to the wellhead with as little loss as possible. 3. The industries' needs for information while deploying technology, management and finance to secure energy supplies and capture value efficiently within the established frameworks to serve its host countries, shareholders and stakeholders. 4. The financial community's need for information to allocate capital appropriately, providing reduced costs and improved long-sightedness through the application of lower risk-compensated discount factors. The projects are categorised with respect to economic and social viability, project feasibility and maturity and uncertainty with respect to the quantities addressed. The categorisation of projects rather than of accumulations provides coherence with other critical management information such as production, cash flows, value and demand for various input factors. This key aspect of UNFC-2009 reflects the critical relationship between the quantities that can be recovered economically and the recovery processes (projects) that must be implemented to achieve those recoveries. It facilitates the recognition of potential wastage of resources through flaring or inefficient recovery processes and therefore also the potential for improvement. Copyright 2011, Society of Petroleum Engineers.

Conference Paper↗

USGS2018

A full annual-cycle conservation strategy for Sprague’s Pipit, Chestnut-collared and McCown’s Longspurs, and Baird’s Sparrow

Sprague’s Pipit ( Anthus spragueii ), Chestnut-collared Longspur ( Calcarius ornatus ), McCown’s Longspur ( Rhynchophanes mccownii ), and Baird’s Sparrow ( Centronyx bairdii ) [hereafter, “the Species”] are North American grassland-obligate songbirds whose populations have experienced significant annual population declines and are the focus of increasing conservation concern. The purpose of this strategy is to summarize current knowledge of the Species and identify priority research, monitoring and conservation actions required to improve their population status. Grasslands are among the most threatened ecosystems in the world with historic losses of 61-70% converted to other land uses, primarily cropland agriculture. Losses continue, with current conversion in the northern Great Plains occurring several times faster than grasslands can be protected. The Partners in Flight North American Landbird Conservation Plan (PIF NALCP) estimates current global populations of 900,000, 3,000,000, 600,000, and 2,000,000 for Sprague’s Pipit, Chestnut-collared Longspur, McCown’s Longspur, and Baird’s Sparrow, respectively. Over the period of 1967-2015, these populations have declined at -3.1, -4.2, -5.9 and -2.2% annually for estimated total losses of 78, 87, 94 and 65%, respectively. Habitat associations of breeding birds, especially at the local scale, represent the majority of the existing scientific literature on the Species’ biology. Landscape-scale associations are more poorly understood, and few studies have linked habitat, at any scale, to population vital rates. Increasing effort is focused on nonbreeding season and very little is known about migration. Current knowledge identifies three primary threats: 1) loss of native grasslands, 2) degradation and fragmentation of remaining native grasslands, and 3) disturbance inconsistent with needs of the Species. Top priorities for future research include: identification of population limiting factors, links between breeding habitat and demographics, identification of migratory habitat requirements, and identification of conditions promoting winter survival. Implementation strategies must focus on the protection, restoration, and enhancement (i.e., management) of grassland communities. Most imperative is the protection of remaining native grasslands from conversion to other uses. Actions supporting grass-based agriculture on privately-owned, native grasslands are paramount. These include incentive-based tools to support livestock grazing that benefits both priority birds and healthy ranching communities, which in turn prevent the conversion of native grasslands to cropland. Where cropland conversion has already taken place, conservation partners should work to continue and improve programs such as the Conservation Reserve Program (CRP) to restore and maintain permanent native cover. This strategy adopts the PIF NALCP objective, which is to reduce the rate of the Species’ decline in the first 10 years, then stabilize and ultimately increase the 2016 population by 5-15% over the subsequent 20 years. Ongoing monitoring programs such as the Breeding Bird Survey, Integrated Monitoring of Bird Conservation Regions, and eBird are critical for informing broadscale demographic and geographic trends for the Species. However, to achieve PIF NALCP goals, there is additional need for monitoring that links habitat conservation accomplishments to population performance within a strategic habitat conservation framework.

Report↗

USGS2025

Harmonization of a water withdrawal dataset for the conterminous United States

The U.S. Geological Survey is developing nationally consistent water-use modeling approaches to replace previous methods relying on locally specific reported and estimated data. These national assessments require datasets that incorporate water withdrawal variability across the United States and over long periods. However, source data often have unclear definitions, missing or varied units, differing temporal resolutions, varied data quality, and inconsistent formats, which hinder automation and require individualized processing. The public-supply datasets described in this paper were used in machine learning models to estimate annual and monthly public-supply water use for 2000–2020 for the conterminous United States (CONUS) and in a model to estimate public-supply deliveries. Public-supply withdrawal data were acquired for the CONUS and the District of Columbia; however, 11 states had annual data for only 1 year, and 10 states had no monthly data. Annual withdrawal data were acquired for 81% of public-supply water service areas, and monthly withdrawal data were acquired for 47% for at least 1 year from 2000 to 2020. These datasets and methods provide the most comprehensive collection of reported public-supply withdrawals to date and can be used by water-use managers, the scientific community, and the broader public. The extensive data processing described herein can be applicable to datasets representing other categories of water use.

conterminous United States↗

USGS2013

Unique challenges facing Southwestern tribes: Chapter 17

Executive Summary When considering climate change, risks to Native American lands, people, and cultures are noteworthy. Impacts on Native lands and communities are anticipated to be both early and severe due to their location in marginal environments. Because Native American societies are socially, culturally, and politically unique, conventional climate change adaptation planning and related policies could result in unintended consequences or conflicts with Native American governments, or could prove to be inadequate if tribal consultation is not considered. Therefore, it is important to understand the distinct historical, legal, and economic contexts of the vulnerability and adaptive capacity of Southwestern Native American communities. The key messages presented in this chapter are: • Vulnerability of Southwestern tribes is higher than that for most groups because it is closely linked to endangered cultural practices, history, water rights, and socio-economic and political marginalization, characteristics that most Indigenous people share. (high confidence) • Very little data are available that quantify the changes that are occurring or that establish baseline conditions for many tribal communities. Additional data are crucial for understanding impacts on tribal lands for resource monitoring and scientific studies. (high confidence) • The scant data available indicate that at least some tribes may already be experiencing climate change impacts. (medium confidence) • Tribes are taking action to address climate change by instituting climate-change mitigation initiatives, including utility-scale, alternative-energy projects, and energy-conservation projects. Tribes are also evaluating their existing capacity to engage in effective adaptation planning, even though financial and social capital is limited.

Book chapter↗

USGS2019

Black Carp in North America: A description of range, habitats, time of year, and methods of reported captures

Black Carp Mylopharyngodon piceus are considered invasive in North America. Since the first wild capture in 2003, collection records have increased, yet information summarizing successful collection methods is lacking. Reported capture methods throughout the Black Carp's native and introduced ranges vary providing minimal aid for determining control and monitoring methods. Here, we describe the current species range and the spatial and temporal variation among captures. The size of fish can affect capture; thus, we report captured fish and gear dimensions and recommend appropriate scientific collection methods. We focus on collection data from 302 Black Carp ranging from 410 to 1,607 mm total length received from 2011 to February 2019. The reported range of Black Carp has expanded in the Cumberland, Illinois, Mississippi, Missouri, Ohio, and Tennessee rivers. Captures most frequently occurred in channel (41%), side‐channel (24%), and backwater (22%) habitat types, with increased records in May, June, and July. Most records were commercial captures, of which hoop net (51%) and gill net (26%) were most common. Results suggest that standard scientific methods for sampling fish in large rivers and standing water by hoop net and gill net may be used to monitor Black Carp, but a robust study design needs to be applied to determine gear selectivity and to determine if catch rates are density dependent or incidental.

North American Journal of Fisheries Management↗

USGS2011

Mount St. Helens: A 30-year legacy of volcanism

The spectacular eruption of Mount St. Helens on 18 May 1980 electrified scientists and the public. Photodocumentation of the colossal landslide, directed blast, and ensuing eruption column—which reached as high as 25 kilometers in altitude and lasted for nearly 9 hours—made news worldwide. Reconnaissance of the devastation spurred efforts to understand the power and awe of those moments (Figure 1). The eruption remains a seminal historical event—studying it and its aftermath revolutionized the way scientists approach the field of volcanology. Not only was the eruption spectacular, but also it occurred in daytime, at an accessible volcano, in a country with the resources to transform disaster into scientific opportunity, amid a transformation in digital technology. Lives lost and the impact of the eruption on people and infrastructure downstream and downwind made it imperative for scientists to investigate events and work with communities to lessen losses from future eruptions.

Washington↗

USGS2011

Team investigates activity at Mt. Semeru, Java, volcano

In February 1994 a large eruption continued a pattern of activity that Mt. Semeru volcano—the highest mountain in Java, Indonesia—has exhibited since 1967. Mt. Semeru lies south of the Tengger Caldera, which encloses the volcano Mt. Bromo. Together, they form one of the largest volcanic complexes in the province of East Java. Although Mt. Semeru is one of the most continuously active volcanos in Indonesia, it has been the subject of few scientific investigations. Observations of the volcano's activity are made from a distance and compiled in monthly and annual reports by the Volcanological Survey of Indonesia (VSI), but the most recent detailed map of the summit region was published in 1938 in the Atlas of the Dutch Colonies.

Java, Mount Semeru↗

USGS1987

Faces from the past: Frederic Morton Chamberlain (1867-1921), pioneer fishery biologist of the American West

The life of Frederic Morton Chamberlain (1867–1921) was marked by his many contributions to fishery science. As an assistant with the old U.S. Bureau of Fisheries, he pioneered life history studies of salmon in California and Alaska, and assisted in the collection of hundreds of thousands of natural history specimens from the Pacific Ocean as resident naturalist on the U.S.S. Albatross . He was innovative in the use of field photography in fishery work, and the design and construction of capture nets and collecting gear. His detailed reports were important in documenting the conditions of the native ichthyofauna in Alaska, Arizona, and California at the turn of the century and have been heavily relied upon by subsequent investigators. His ability to design and conduct scientifically justifiable studies to solve fishery problems while under many kinds of hardships is a testament to his background and dedication to the field. He represents the prototype of the modern fishery biologist.

Fisheries↗

USGS2011

Effort explores 130 Million years of Antarctic paleoenvironment

Antarctic climate history has been dominated by events and turning points with causes that are poorly understood. To fill the gaps in our knowledges new effort is underway in the international geologic community to acquire and coordinate the circum‐Antarctic geologic data needed to derive and model paleoenvironments of the past 130 m.y. The effort, which focuses principally on using shallow (<100 m) stratigraphic drilling and coring to acquire the geologic data, is being led by the Antarctic Offshore Stratigraphy Project (ANTOSTRAT), a group that works under the aegis of the Scientific Committee on Antarctic Research (SCAR). About 40 scientists from 12 countries met this past summer in Wellington, New Zealand, at an ANTOSTRAT meeting to discuss strategies for implementing the desired paleoenvironmental field and modeling studies. The meeting was held in conjunction with the 8th International Symposium on Antarctic Earth Sciences.

Eos, Transactions, American Geophysical Union↗

USGS1957

Limnological surveys of the Great Lakes--early and recent

Early explorations on the Great Lakes were concerned largely with things easily collected or observed—common organisms, water levels, surface temperatures … Even when more scientific studies were undertaken, they were at first scattered and small-scale. Effective surveys became possible only through inter-agency cooperation which permits a pooling of facilities, staff, and equipment. Expansion of limnological research on the Great Lakes has been rapid in later years and the outlook for the future is good.

Transactions of the American Fisheries Society↗

USGS2006

Earthquake hazards: A national threat

Earthquakes are one of the most costly natural hazards faced by the Nation, posing a significant risk to 75 million Americans in 39 States. The risks that earthquakes pose to society, including death, injury, and economic loss, can be greatly reduced by (1) better planning, construction, and mitigation practices before earthquakes happen, and (2) providing critical and timely information to improve response after they occur. As part of the multi-agency National Earthquake Hazards Reduction Program, the U.S. Geological Survey (USGS) has the lead Federal responsibility to provide notification of earthquakes in order to enhance public safety and to reduce losses through effective forecasts based on the best possible scientific information.

Fact Sheet↗

USGS2020

Hydrogeologic units, contour maps, and cross sections of the Boone and Roubidoux aquifers, northeastern Oklahoma, 2020

The Boone and Roubidoux aquifers (or their equivalents) are the main sources of fresh groundwater in northeastern Oklahoma. Projected total water demand of both surface water and groundwater in northeastern Oklahoma is expected to increase approximately 56 percent from 2010 to 2060. This report provides an overview of the hydrogeology of northeastern Oklahoma, with an emphasis on the hydrogeologic units composing and surrounding the Boone and Roubidoux aquifers (the Western Interior Plains confining unit, the Boone aquifer, the Ozark confining unit, and the Roubidoux aquifer). This report also provides the hydrogeologic framework for an ongoing (as of 2020) hydrologic investigation to aid the Oklahoma Water Resources Board in determining the maximum annual yields of the Boone and Roubidoux aquifers. As a first step of this ongoing hydrologic investigation, the U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board and U.S. Army Corps of Engineers, developed hydrogeologic-unit maps, contour maps for the bases of the four hydrogeologic units, and generalized cross sections to further characterize the hydrogeologic framework of the Boone and Roubidoux aquifers. The contour maps illustrate the altitudes of the bases of each hydrogeologic unit. The altitude of the base of the Western Interior Plains confining unit ranged from 1,316 to −6,437 feet (ft) relative to North American Vertical Datum of 1988. The altitude of the base of the Boone aquifer ranged from 1,327 to −6,681 ft. The altitude of the base of the Ozark confining unit ranged from 1,275 to −6,720 ft. The altitude of the base of the Roubidoux aquifer ranged from 403 to −9,488 ft.

Oklahoma↗

USGS1984

Estimating the effect of hunting on annual survival rates of adult mallards

Management programs for waterfowl populations include rationale for, and establishment of, hunting regulations. These programs rest partially on the results of scientific studies on the effect of harvest rates on annual survival rates. The evidence of this relationship has changed markedly since the mid-1970's, and it is not widely believed that a largely compensatory relationship exists between hunting mortality and other forms of mortality for the mallard ( Anas platyrhynchos ). This paper employs a general probabilistic model formulated to include a parameter (b) representing a continuum between complete compensation (b=0) and total additivity (b=1). Maximum likelihood estimates of this parameter were computer for 47 data sets of adult mallards banded throughout North American before hunting commenced. We found additional evidence of a highly compensatory mortality process for adult male mallards, while the evidence for adults female mallards remains inconclusive. Effective harvest, land acquisition, and land management programs depend upon additional information on the chronology and mechanisms underlying a compensatory mortality process.

Journal of Wildlife Management↗

USGS2017

Centennial-scale reductions in nitrogen availability in temperate forests of the United States

Forests cover 30% of the terrestrial Earth surface and are a major component of the global carbon (C) cycle. Humans have doubled the amount of global reactive nitrogen (N), increasing deposition of N onto forests worldwide. However, other global changes—especially climate change and elevated atmospheric carbon dioxide concentrations—are increasing demand for N, the element limiting primary productivity in temperate forests, which could be reducing N availability. To determine the long-term, integrated effects of global changes on forest N cycling, we measured stable N isotopes in wood, a proxy for N supply relative to demand, on large spatial and temporal scales across the continental U.S.A. Here, we show that forest N availability has generally declined across much of the U.S. since at least 1850 C.E. with cool, wet forests demonstrating the greatest declines. Across sites, recent trajectories of N availability were independent of recent atmospheric N deposition rates, implying a minor role for modern N deposition on the trajectory of N status of North American forests. Our results demonstrate that current trends of global changes are likely to be consistent with forest oligotrophication into the foreseeable future, further constraining forest C fixation and potentially storage.

Scientific Reports↗

USGS2025

American alligators (Alligator mississippiensis) as wetland ecosystem carbon stock regulators

Blue carbon refers to organic carbon sequestered by oceanic and coastal ecosystems. This stock has gained global attention as a high organic carbon repository relative to other ecosystems. Within blue carbon ecosystems, tidally influenced wetlands alone store a disproportionately higher amount of organic carbon than other blue carbon systems. North America harbors 42% of tidally influenced global wetland area, which has been identified as a critical carbon stock in the context of climate change mitigation. However, quantified associations between vertebrate biota and carbon sequestration within ecosystems are in their infancy and have been incidental, given that microbial trophic levels are thought to drive nutrient dynamics. Here, we assess the relationship between American alligator ( Alligator mississippiensis ) demography and tidally influenced wetland soil carbon stock among habitats at continental, biogeographically-relevant, and local scales. We used soil core profile data from the Smithsonian’s Coastal Carbon Network and filtered for continuous core profiles in tidally influenced wetland areas along the Gulf and Atlantic Coasts of the United States. Results indicate that American alligator presence is positively correlated with soil carbon stock across habitats within their native distribution. Further, American alligator demographic variables are positively correlated with soil carbon stock at local scales. These conclusions are concordant with previous findings that apex predators, through trophic cascade theory, play a key role in regulating soil carbon stock and that alligators are functional apex predators in carbon dynamics and a key commercialized natural resource.

Connecticut, Delaware, Florida, Georgia, Louisiana↗

USGS2011

Scientific drilling into the San Andreas Fault Zone

This year, the world has faced energetic and destructive earthquakes almost every month. In January, an M = 7.0 event rocked Haiti, killing an estimated 230,000 people. In February, an M = 8.8 earthquake and tsunami claimed over 500 lives and caused billions of dollars of damage in Chile. Fatal earthquakes also occurred in Turkey in March and in China and Mexico in April.

California↗