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At least 37 records · Page 2Linked to original sources
USGS2024

Prefabricated Zero Ascend Omnispecies (ZAO) modular fish passage modules using advanced manufacturing techniques

The Zero Ascend Omnispecies (ZAO) fish passage attraction module “ZAO Attractor” is a novel system designed to facilitate upstream passage for a broad spectrum of fish species, with a particular focus on American shad and river herring (alewife and/or blueback herring). Combining the use of prefabricated, modular components with advanced manufacturing, the ZAO aims to provide a cost-effective and scalable solution for fish passage attractions across various hydropower sites. The system features a surface level entry, so fish do not need to climb. In addition, it is designed to be adjusted and repositioned to create the most effective attraction flows by managing the outflows from hydropower turbines. Budget Period 1 (BP1) focused on the design and modeling of the ZAO Attractor and demonstrated the engineering feasibility of a modular, prefabricated, hydrodynamically efficient structure with surface level entry and passage. During BP1, the hypothesis was that certain structural adaptations, such as the addition of long fins, could direct turbine outflows to create a desirable downstream flow. Simulations, however, were inconclusive, revealing the complex nature of fish preferences for hydraulic conditions. It was discovered that there were limited published studies on the direct correlation between quantified flow patterns and fish attraction, emphasizing the need for controlled studies to observe and measure these effects. In Budget Period 2 (BP2), controlled studies with live fish were prioritized to address these complexities. A partially scaled ZAO Attractor was evaluated in laboratory conditions using native river water to assess its capability to attract and guide fish. Despite challenges with flume flow conditions and the impact of flume dimensions on flow directionality and velocity, the studies provided insights into fish behavior and preferences, particularly the requirement for a consistent flow stream for migration cues. Adjustments to the fin structure demonstrated potential effectiveness in guiding fish toward the module. However, the hydraulic conditions within the flume environment did not accurately reflect typical in-river scenarios, therefore the results were inconclusive with respect to the optimal system configuration for in-river use. In the future, conducting comprehensive field studies can enhance understanding of the interactions between fish behavior and flow conditions created by the ZAO Attractor. Additionally, a design review is advised, particularly regarding the load scenarios throughout the seasons and positioning of the ZAO Attractor. These studies should continue to refine the design to achieve its intended benefits: economical and effective fish attraction and passage that can be adapted to specific site conditions while allowing for continued energy generation at sites up for re-licensure and adding hydropower generation to previously untapped resources in non-powered dams and new stream reaches. In conclusion, the ZAO fish passage attraction module presents a promising approach to fish passage at hydropower stations, with the potential to balance environmental concerns with renewable energy development. However, further field validation and optimization are necessary to ensure its effectiveness and practicality in real-world applications.

Final Technical Report↗
USGS2021

Cloud water interception in Hawai‘i: Developing capacity to characterize the spatial patterns and effects on water and ecological processes responses in Hawai‘i

Cloud-water interception (CWI) is the process by which fog or cloud water droplets are captured and accumulate on the leaves and branches of plants, some of which drips to the ground. Prior studies in Hawai'i indicate that CWI is highly variable and can contribute substantially to total precipitation. In this study, we monitored CWI and other processes at five mountain field sites on the Islands of Oʻahu, Maui, and Hawaiʻi to explore how CWI (1) varies with different climate and vegetation characteristics, (2) affects plant water use and growth, and (3) contributes to water resources. Results show that annual CWI varied from 158 to 910 mm, accounting for 3-34% of total water input at individual sites. This large variation was caused by differences in the quantity of cloud water, wind speed, and vegetation structure between sites. We developed a model to predict CWI using both climatic and forest canopy characteristics. On average, the model underestimated annual CWI by 18%, but reproduced the site differences relatively well. Plant water use decreased during periods of fog events mainly because of associated higher humidity. This new CWI model can be used to assess impacts of climate and land cover change on CWI and provide valuable information for resource management in Hawai‘i, which was not previously possible. At one field site, we explored the impacts of fog water on hydrological and ecological processes. Fog effects on native plant growth were indirect, primarily buffering effects of solar radiation. Removal of grass allowed natural regeneration of seedlings but did not alter soil moisture values. A soil data-collection program was initiated to help evaluate the role CWI has in providing moisture for plants, reducing wildfire risk within the fog zone, and contributing to groundwater recharge to aquifers that supply drinking water and groundwater discharge to streams.

Hawaii↗
USGS2025

Evolution of permeability and strength recovery of shear fracture under hydrothermal conditions

Geothermal energy is a clean and renewable resource that depends on the ability to move water through hot rock. In many locations, the ability to move water through rock requires the presence of extensive natural or human-made systems of fractures. However, these fracture systems are influenced by a variety of complex processes that occur at the temperature and pressure conditions found in geothermal reservoirs. To make geothermal systems more efficient, it is important to understand how these fractures evolve over time in response to these processes. This study explored how fractures in rock change under high-temperature and pressure conditions, like those found in geothermal reservoirs, through laboratory experiments and numerical simulations. In general fractures, tend to close due to pressure from the surrounding rock preventing the flow of water. One set of laboratory experiments revealed that fractures in granitic rock can weaken over time at elevated temperatures. These weak fractures can then slip slowly potentially keeping the fracture open for a longer period. This study also showed that at the highest temperature examined (250 °C) large differences between the chemical composition of the rock and the fluid moving through it could improve water flow temporarily likely due to the water dissolving parts of the rock. Flow rate predicted by models shows overall good agreement with the flow rate measured in our experiments but with some long time-scale variations that may be due to mechanical wear of the fracture surface. A second set of experiments found that, over the temperature range examined, the closure of fractures was caused by brittle failure driven by high stresses at points where fracture surfaces were in contact. This result suggests that fracture closure in geothermal reservoirs could be counteracted by maintaining high pore pressures. Additionally, we also tested a new method using electrical resistance to measure fracture closure in controlled systems with high precision.

Final Technical Report↗
USGS1975

Author index to published ERTS-1 reports

This index has been compiled to assist the reader in locating and obtaining reports on the 334 scientific experiments conducted under the National Aeronautics and Space Administration (NASA) Earth Resources Technology Satellite-1 (ERTS-1) (renamed Landsat) program. Each NASA-designated experimenter was required to submit written reports on his investigation: these were designated type 1, type 2, and type 3 reports. Type 1 reports were periodic (monthly or bimonthly) progress summaries; type 2 were comprehensive scientific and technical reports; and type 3 were final report. Investigators were also encourage to present their more significant findings in professional or technical journals and proceedings of symposia.

Report↗
USGS1995

The strategy for improving water-quality monitoring in the United States; final report of the Intergovernmental Task Force on Monitoring Water Quality; technical appendices

The Intergovernmental Task Force on Monitoring Water Quality (ITFM) prepared this report in collaboration with representatives of all levels of government and the private sector. The report recommends a strategy for nationwide water-quality monitoring and technical monitoring improvements to support sound water-quality decisionmaking. The strategy is intended to achieve a better return on public and private investments in monitoring, environmental protection, and natural resources management. It is also designed to expand the base of information useful to a variety of users at multiple geographic scales. Institutional and technical changes are needed to improve water-quality monitoring and to meet the full range of monitoring requirements. Monitoring must be incorporated as a critical element of program planning, implementation, and evaluation. The strategy includes recommendations in many key elements, such as the development of goal-oriented monitoring and indicators, institutional collaboration, and methods comparability. Initial actions have been taken to implement the strategy. Several Federal agencies have jointly purchased and shared remotely sensed land-cover information needed for water assessment. Major agency data systems are using common data-element names and reference tables that will ensure easy sharing of data. A number of States have held meetings with collectors of water information to initiate statewide monitoring strategies. New monitoring guidance has been developed for Federal water-quality grants to States. Many State offices have changed monitoring programs to place emphasis on priority watersheds and to improve assessment of water quality. As the competition increases for adequate supplies of clean water, concerns about public health and the environment escalate, and more demands are placed on the water information infrastructure. To meet these demands, the collaborative approach has already produced benefits, which will continue to grow as the recommendations are implemented

Open-File Report↗
USGS2003

Hydrogeology Journal in 2002

Hydrogeology Journal appeared in six issues containing a total of 674 pages and 47 major articles, including 22 Papers and 24 Reports, as well as Technical Notes and Book Reviews. The final issue of 2002 also contained the annual volume index. Hydrogeology Journal (HJ) is an international forum for hydrogeology and related disciplines. Authors in 2002 were from about 30 countries. Articles advanced hydrogeologic science and described hydrogeologic systems in many regions worldwide. These articles focused on 22 countries: Afghanistan, Argentina, Australia, Austria, Belgium, Brazil, Canada, China, India, Israel, Japan, Jordan, Mexico, New Zealand, Nigeria, Portugal, Qatar, Switzerland, Syria, Turkey, UK, and the USA. The Guest Editors of the 2002 HJ theme issue on "Groundwater Recharge", Bridget R. Scanlon and Peter G. Cook, assembled a highly relevant and sought-after collection of papers from eminent authors on wide-ranging aspects of the subject.

Hydrogeology Journal↗
USGS2011

Final report on the Seventh International Comparison of Absolute Gravimeters (ICAG 2005)

The Bureau International des Poids et Mesures (BIPM), Sevres, France, hosted the 7th International Comparison of Absolute Gravimeters (ICAG) and the associated Relative Gravity Campaign (RGC) from August to September 2005.;ICAG 2005 was prepared and performed as a metrological pilot study, which aimed:;(1) To determine the gravity comparison reference values;;(2) To determine the offsets of the absolute gravimeters; and;(3) As a pilot study to accumulate experience for the CIPM Key Comparisons.;This document presents a complete and extensive review of the technical protocol and data processing procedures. The 1st ICAG-RGC comparison was held at the BIPM in 1980-1981 and since then meetings have been organized every 4 years.;In this paper, we present an overview of how the meeting was organized, the conditions of BIPM gravimetric sites, technical specifications, data processing strategy and an analysis of the final results. This 7th ICAG final report supersedes all previously published reports.;Readings were obtained from participating instruments, 19 absolute gravimeters and 15 relative gravimeters. Precise levelling measurements were carried out and all measurements were performed on the BIPM micro-gravity network which was specifically designed for the comparison.

Metrologia↗
USGS2008

Interactions among livestock grazing, vegetation type, and fire behavior in the Murphy Wildland Fire Complex in Idaho and Nevada, July 2007

A series of wildland fires were ignited by lightning in sagebrush and grassland communities near the Idaho-Nevada border southwest of Twin Falls, Idaho in July 2007. The fires burned for over two weeks and encompassed more than 650,000 acres. A team of scientists, habitat specialists, and land managers was called together by Tom Dyer, Idaho BLM State Director, to examine initial information from the Murphy Wildland Fire Complex in relation to plant communities and patterns of livestock grazing. Three approaches were used to examine this topic: (1) identify potential for livestock grazing to modify fuel loads and affect fire behavior using fire models applied to various vegetation types, fuel loads, and fire conditions; (2) compare levels of fuel consumed within and among major vegetation types; and (3) examine several observed lines of difference and discontinuity in fuel consumed to determine what factors created these contrasts. The team found that much of the Murphy Wildland Fire Complex burned under extreme fuel and weather conditions that likely overshadowed livestock grazing as a factor influencing fire extent and fuel consumption in many areas where these fires burned. Differences and abrupt contrast lines in the level of fuels consumed were affected mostly by the plant communities that existed on a site before fire. A few abrupt contrasts in burn severity coincided with apparent differences in grazing patterns of livestock, observed as fence-line contrasts. Fire modeling revealed that grazing in grassland vegetation can reduce surface rate of spread and fire-line intensity to a greater extent than in shrubland types. Under extreme fire conditions (low fuel moisture, high temperatures, and gusty winds), grazing applied at moderate utilization levels has limited or negligible effects on fire behavior. However, when weather and fuel-moisture conditions are less extreme, grazing may reduce the rate of spread and intensity of fires allowing for patchy burns with low levels of fuel consumption. The team suggested that targeted grazing to accomplish fuel objectives holds promise but requires detailed planning that includes clearly defined goals for fuel modification and appropriate monitoring to assess effectiveness. It was recommended that a pilot plan be devised to strategically place grazed blocks across a landscape to create fuel-reduction bands capable of influencing fire behavior. Also suggested was the development of a general technical report that highlights information and examples of how livestock grazing influences fire extent, severity, and intensity. Finally, the team encouraged continued research and monitoring of the effects of the Murphy Wildland Fire Complex. Much more can be learned from the effects of this extensive fire complex that may offer insight for future management decisions.

Open-File Report↗
USGS2004

Editors' message: Hydrogeology Journal in 2003

Hydrogeology Journal appeared in six issues containing a total of 710 pages and 48 major articles, including 31 Papers and 14 Reports, as well as some Technical Notes and Book Reviews. The number of submitted manuscripts continues to increase. The final issue of 2003 also contained the annual volume index. Hydrogeology Journal ( HJ ) is an international forum for hydrogeology and related disciplines and authors in 2003 were from about 28 countries. Articles advanced hydrogeologic science and described hydrogeologic systems in many regions worldwide. These articles focused on a variety of general topics and on studies of hydrogeology in 24 countries: Afghanistan, Algeria, Argentina, Australia, Bangladesh, Belgium, Canada, Chile, China, Denmark, France, India, Italy, Mexico, Netherlands, New Zealand, Nigeria, Norway, Portugal, Russia, South Africa, Switzerland, Turkey, and U.S.A. The Guest Editor of the 2003 HJ theme issue on “Hydromechanics in Geology and Geotechnics”, Ove Stephansson, assembled a valuable collection of technical reviews and research papers from eminent authors on important aspects of the subject area.

Hydrogeology Journal↗
USGS2003

Information technology challenges of biodiversity and ecosystems informatics

Computer scientists, biologists, and natural resource managers recently met to examine the prospects for advancing computer science and information technology research by focusing on the complex and often-unique challenges found in the biodiversity and ecosystem domain. The workshop and its final report reveal that the biodiversity and ecosystem sciences are fundamentally information sciences and often address problems having distinctive attributes of scale and socio-technical complexity. The paper provides an overview of the emerging field of biodiversity and ecosystem informatics and demonstrates how the demands of biodiversity and ecosystem research can advance our understanding and use of information technologies.

Information Systems↗
USGS1975

Utilization of Skylab (EREP) system for appraising changes in continental migratory bird habitat

The author has identified the following significant results. Surface water statistics using data obtained by supporting aircraft were generated. Signature extraction and refinement preliminary to wetland and associated upland vegetation recognition were accomplished, using a selected portion of the aircraft data. Final classification mapping and analysis of surface water trends will be accomplished.

Technical Report↗
USGS2016

Facilitating the inclusion of nonmarket values in Bureau of Land Management planning and project assessments—Final report

Executive Summary This report summarizes the results of a series of field-based case studies conducted by the U.S. Geological Survey (USGS) to (1) evaluate the use of nonmarket values in Bureau of Land Management (BLM) planning and project assessments, (2) update existing technical resources for measuring those values, and (3) provide guidance to field staff on the use of nonmarket values. Four BLM pilot sites participated in this effort: Canyons of the Ancients National Monument in Colorado, Red Cliffs and Beaver Dam Wash National Conservation Areas in Utah, BLM’s Taos Field Office in New Mexico, and BLM's Tuscarora Field Office in Nevada. The focus of the case studies was on practical applications of nonmarket valuation. USGS worked directly with BLM field staff at the pilot sites to demonstrate the process of considering nonmarket values in BLM decisionmaking and document the questions, challenges, and opportunities that arise when tying economic language to projects. As part of this effort, a Web-based toolkit, available at https://my.usgs.gov/benefit-transfer/ , was updated and expanded to help facilitate benefit transfers (that is, the use of existing economic data to quantify nonmarket values) and qualitative discussions of nonmarket values. A total of 53 new or overlooked nonmarket valuation studies comprising 494 nonmarket value estimates for various recreational activities and the preservation of threatened, endangered, and rare species were added to existing databases within this Benefit Transfer Toolkit. In addition, four meta-regression functions focused on hunting, wildlife viewing, fishing, and trail use recreation were developed and added to the Benefit Transfer Toolkit. Results of this effort demonstrate that there are two main roles for nonmarket valuation in BLM planning. The first is to improve the decisionmaking process by contributing to a more comprehensive comparison of economic benefits and cost when evaluating resource tradeoffs for National Environmental Policy Act analyses. The second is to use economic language and information on economic values, either qualitative or quantitative, to improve the ability to communicate the economic significance of the resources provided by BLM-managed lands. Findings also indicate that the use of existing economic data to quantify nonmarket values (that is, benefit transfer) poses unique challenges because of the scarcity of both resource data and existing valuation studies focused on resources and sites managed by BLM. This highlights the need for improvements in the collection of resource data at BLM sites, especially visitor use data, as well as an opportunity for BLM’s Socioeconomics Program to strategically identify priority areas, in terms of both resources and geographic locations, where primary valuation studies could be conducted and the results used for future benefit transfers. Finally, whereas qualitative discussions of nonmarket values do not facilitate the comparison of monetized values, they can provide a manageable next step forward in providing more comprehensive information on nonmarket values for BLM plans and project assessments.

Open-File Report↗
USGS2014

Palila restoration research, 1996−2012

The Palila Restoration Project was initiated in 1996 by the U.S. Geological Survey to assist government agencies mitigate the effects of realigning Saddle Road (Highway 200) through Palila Critical Habitat (U.S. Fish and Wildlife Service 1998, Federal Highway Administration 1999). Ecological research on the palila (Loxioides bailleui), an endangered Hawaiian forest bird, carried out by the U.S. Geological Survey (formerly organized as the Research Division of U.S. Fish and Wildlife Service) since 1987 and research conducted by the Palila Restoration Project provided the scientific bases for developing a recovery strategy (U.S. Fish and Wildlife Service 2006) and its adaptive implementation. The main objectives of the Palila Restoration Project were to develop techniques for reintroducing the palila to a portion of its former range, investigate the biological threats to the palila and its habitat, and synthesize the existing body of ecological knowledge concerning the palila. Five broad study themes formed the research framework: 1. Population reintroduction and restoration 2. Demography and breeding ecology 3. Habitat use and food ecology 4. Vegetation ecology 5. Predator ecology and management An element that was not included in the research program of the project was the ecology and management of introduced ungulates, which has historically constituted the single greatest threat to Palila Critical Habitat (Banko et al. 2009). The absence of ungulate studies should not be interpreted to mean that we believe ungulates no longer damage palila habitat. Other research has already established that removing alien browsers and grazers from Mauna Kea is essential for the recovery of the subalpine forest on which palila now depend (Scowcroft and Giffin 1983; Scowcroft and Sakai 1983; Scowcroft and Conrad 1988, 1992; Hess et al. 1999). Moreover, the Federal District Court of Hawai‘i has ordered the state of Hawai‘i to remove browsing ungulates from Palila Critical Habitat (Banko et al. 2009, Hess and Banko 2011). This final report summarizes results of Palila Restoration Project research from December 1996 to December 2012. Even though some results contained in this report have been published in scientific journals and other technical reports (Appendix I), they are included here to provide a comprehensive chronicle of all project activities.

Hawaii↗
USGS2015

Palila Restoration Research, 1996−2012. Summary and management implications

The Palila Restoration Project was initiated in 1996 by the U.S. Geological Survey to assist government agencies mitigate the effects of realigning Saddle Road (Highway 200) through Palila Critical Habitat (U.S. Fish and Wildlife Service 1998, Federal Highway Administration 1999). Ecological research on the palila (Loxioides bailleui), an endangered Hawaiian forest bird, carried out by the U.S. Geological Survey (formerly organized as the Research Division of U.S. Fish and Wildlife Service) since 1987 and research conducted by the Palila Restoration Project provided the scientific bases for developing a recovery strategy (U.S. Fish and Wildlife Service 2006) and its adaptive implementation. The main objectives of the Palila Restoration Project were to develop techniques for reintroducing the palila to a portion of its former range, investigate the biological threats to the palila and its habitat, and synthesize the existing body of ecological knowledge concerning the palila. Five broad study themes formed the research framework: 1. Population reintroduction and restoration 2. Demography and breeding ecology 3. Habitat use and food ecology 4. Vegetation ecology 5. Predator ecology and management An element that was not included in the research program of the project was the ecology and management of introduced ungulates, which has historically constituted the single greatest threat to Palila Critical Habitat (Banko et al. 2009). The absence of ungulate studies should not be interpreted to mean that we believe ungulates no longer damage palila habitat. Other research has already established that removing alien browsers and grazers from Mauna Kea is essential for the recovery of the subalpine forest on which palila now depend (Scowcroft and Giffin 1983; Scowcroft and Sakai 1983; Scowcroft and Conrad 1988, 1992; Hess et al. 1999). Moreover, the Federal District Court of Hawai‘i has ordered the State of Hawai‘i to remove browsing ungulates from Palila Critical Habitat (Banko et al. 2009, Hess and Banko 2011). This final report summarizes results of Palila Restoration Project research from December 1996 to December 2012. Even though some results contained in this report have been published in scientific journals and other technical reports (Appendix I), they are included here to provide a comprehensive chronicle of all project activities.

Hawaii↗
USGS2013

Science-based management of public lands in southern Nevada

Landmark legislation provides guiding principles for land management planning in southern Nevada and the rest of the United States. Such legislation includes, but is not limited to, the Forest Service Organic Administration Act of 1897 (16 U.S>C. 473-478, 479-482 and 551), National Park Service Organic Act of 1916 (U.S.C. Title 16, Secs. 1-4). Wilderness Act 1964 (P.L.88-577), National Environmental Policy Act of 1969 (P.L. 91-190), Endangered Species Act of 1973 (P.L. 91-205), National Forest Management Act of of 1976 (P.L. 94-588), and Federal Land Policy and Management Act of 1976 (P.L. 94-579). The acts establishing congressionally designated areas within southern Nevada, such as Lake Mead National Recreation Area, Spring Mountains National Restoration Area, and Desert National Wildlife Refuge, also contain guidelines for the management of these lands. These documents variously require preservation of natural and cultural resource and wilderness character, protection of species, and prevention of undesirable environmental effects from land management actions. These requirements must be met while allowing for multiple "uses" of certain public lands (e.g. recreation, ranching, resources extraction, renewable energy development, etc.) to the degree that they do no threaten preservation, protection, and prevention goals,. many considerations some into play in the development and implementation for land management plans and actions. The planning process requires a balancing act that sometimes pit one need or priority against another. When priorities can trump other needs can prioritized and receive disproportionate consideration. Overall, the management of public lands is a very complicated and sometime contentious process. Science provides an objective way to help weigh quantifiable information and draw conclusions about the effects of past and potential future land management policies, decisions, and actions. When effectively integrated into adaptive management, science-based information can reduce uncertainties, increase knowledge, and improve decision making. However, the specific science information needed for effective management is often lacking or difficult to access or interpret. Science is typically reported in scientific journals as discrete units describing individual studies with other scientists as the primary audience. Translations of these studies an synthesis or multiple studies into formats that can be readily used in land management planning efforts are often lacking. Identifying and articulating the highest priority science and research needs is one of the primary purposes of the Southern Nevada Agency Partnership (SNAP; http://www.SNAP.gov) Science and Research Team (chapter 1; Turner and others 2009). The SNAP Science and Research Strategy (Strategy) calls for a synthesis report to be written every 5 years summarizing the state of knowledge, information gaps and management implications of scientific information as it relates to the SNAP Strategy goals (Turner and others 2009). This General Technical Report serves as the first SNAP Science and Research Synthesis Report (Synthesis Report) commissioned by the Science and Research Team. The Synthesis Report is mostly based on information form the peer-reviewed scientific literature, and is itself peer reviewed and constitutes a new contribution to the scientific literature. This final chapter addresses Sub-goal 2.3, which is to manage current and future authorized southern Nevada land uses in a manner that balances public need and ecosystem sustainability, and Sub-goal 2.5, which is to promote an effective conservation education and interpretation program to improve the quality of resources and enhance public use and enjoyment of southern Nevada public lands. It summarizes information form the previous chapters on what scientific information is known currently and what remains largely unknown, and it discusses how science can be used to make future management decisions that balances public needs and ecosystem sustainability.

Nevada↗
USGS2023

Panel review of Ground Motion Characterization Model in 2023 NSHM

The 2023 National Seismic Hazard Model (NSHM; Petersen et al., 2023) has two major components – a seismic source characterization (SSC) model and a ground motion characterization (GMC) model. The US Geological Survey (USGS) established separate panels to review and provide input on these two models. Both panels are advisory, meaning that they provide input on technical issues for consideration by the USGS NSHM team, but they do not have decision making authority. Here, we report on the activities and recommendations of the Ground Motion Characterization Panel, made up of the authors of this review. Final modeling decisions are presented in separate USGS documents, including Petersen et al., (2023) and Moschetti et al., (2023). Where modeling decisions depart from our recommendations, the rationale is explained in those publications.

Report↗