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At least 1,711 records · Page 95Linked to original sources
USGS2006

Fish health study Ashtabula River natural resource damage assessment

INTRODUCTION The Ashtabula River is located in northeast Ohio, flowing into Lake Erie at Ashtabula, Ohio. Tributaries include Fields Brook, Hubbard Run, Strong Brook, and Ashtabula Creek. The bottom sediments, bank soils and biota of Fields Brook have been severely contaminated by unregulated discharges of hazardous substances. Hazardous substances have migrated downstream from Fields Brook to the Ashtabula River and Harbor, contaminating bottom sediments, fish and wildlife. There are presently more than 1,000,000 cubic yards of contaminated sediment in the Ashtabula River and Harbor, much of which originated from Fields Brook. Contaminants include polychlorinated biphenyls (PCBs), chlorinated benzenes, chlorinated ethenes, hexachlorobutadiene, polyaromatic hydrocarbons (PAHs), other organic chemicals, heavy metals and low level radionuclides. A Preassessment Screen, using existing data, was completed for the Ashtabula River and Harbor on May 18, 2001. Among the findings was that the fish community at Ashtabula contained approximately 45 percent fewer species and 52 percent fewer individuals than the Ohio EPA designated reference area, Conneaut Creek. The Ashtabula River and Conneaut Creek are similar in many respects, with the exception of the presence of contamination at Ashtabula. The difference in the fish communities between the two sites is believed to be at least partially a result of the hazardous substance contamination at Ashtabula. In order to investigate this matter further, the Trustees elected to conduct a study of the status and health of the aquatic biological communities of the Ashtabula River and Conneaut Creek in 2002-2004. The following document contains brief method descriptions (more detail available in attached Appendix A) and a summary of the data used to evaluate the health status of brown bullheads (Ameiurus nebulosus) and largemouth bass (Micropterus salmoides) collected from the above sites.

Ohio↗
USGS2006

Vegetation classification for south Florida natural areas

Introduction A critical component of any ecological restoration program is documenting the temporal changes in the spatial extent, pattern, and proportion of plant communities within the landscape. The Comprehensive Everglades Restoration Plan (CERP - www.evergladesplan.org), authorized as part of the Water Resources and Development Act (WRDA) of 2000 (U.S. Congress, 2000), is an $8 billion hydrologic restoration project for all of south Florida. CERP includes 68 separate projects to be managed over the next 30 years by the South Florida Water Management District (SFWMD), the U. S. Army Corp of Engineers (USACE), and other State and Federal agencies. Restoration Coordination and Verification (RECOVER) is a system-wide program of the CERP, designed to organize, manage, and provide the highest quality scientific and technical support during implementation of the restoration program (RECOVER, in prep.). It is the role of RECOVER to develop and implement a system-wide Monitoring and Assessment Plan (MAP) (RECOVER, 2004) and to document how well the CERP is meeting its objectives for ecosystem restoration. One critical component of the MAP is vegetation mapping to document changes in the spatial extent, pattern, and proportion of plant communities within the Everglades landscape. A major aspect of the vegetation mapping project was determining a classification system for labeling vegetation categories utilizing a grid method. The grid method was created specifically for use in the CERP RECOVER vegetation monitoring and assessment project (Rutchey and others, in prep). The CERP RECOVER vegetation mapping project utilizes aerial photography and photointerpretation techniques (with ground truthing) to identify and label vegetation classes. A classification system that had sufficient flexibility and detail to enable the designation of vegetation classes using various remote sensing platforms and identification techniques needed to be developed. The classification system had to be hierarchical, represent distinct ecological communities, individual species, and physical characteristics such as density and height. In addition, it was desirable to have a classification system that allowed exotic species and cattail to be identified using density classes. The classification system was developed specifically for peninsular south Florida and the Florida Keys, from Lake Okeechobee in the north to Key West in the south (Figure 1). Specific areas of interest include Everglades National Park, Big Cypress National Preserve, Biscayne National Park, Florida Panther National Wildlife Refuge, Loxahatchee National Wildlife Refuge, the State of Florida Water Conservation Areas, Holeyland Wildlife Management Area, Rotenberger Wildlife Management Area, J.W. Corbett Wildlife Management Area, Pal-Mar Wildlife Management Area, the Lake Okeechobee Littoral Zones, and additional coastal wetlands of south eastern Miami-Dade County. In addition to being used for mapping of CERP affected areas, the National Park Service-South Florida/Caribbean Network is using the classification for mapping the remaining areas of Everglades National Park and Big Cypress National Preserve outside the CERP footprint, Florida Panther National Wildlife Refuge, Biscayne National Park, and Dry Tortugas National Park.

Florida↗
USGS2006

Concentrations of elements in sediments and selective fractions of sediments, and in natural waters in contact with sediments from Lake Roosevelt, Washington, September 2004

Twenty-eight composite and replicate sediment samples from 8 Lake Roosevelt sites were collected and analyzed for 10 alkali and alkaline earth elements, 2 non-metals, 20 metals, and 4 lanthanide and actinide elements. All elements were detected in all sediment samples except for silver (95 percent of the elements detected for 1,008 analyses), which was detected only in 4 samples. Sequential selective extraction procedures were performed on single composite samples from the eight sites. The percentage of detections for the 31 elements analyzed ranged from 76 percent for the first extraction fraction using a weak extractant to 93 percent for the four-acid dissolution of the sediments remaining after the third sequential selective extraction. Water samples in various degrees of contact with the sediment were analyzed for 10 alkali and alkaline earth elements, 5 non-metals, 25 metals, and 16 lanthanide and actinide elements. The filtered water samples included 10 samples from the reservoir water column at 8 sites, 32 samples of porewater, 55 samples from reservoir water overlying sediments in 8 cores from the site incubated in a field laboratory, and 24 water samples that were filtered after being tumbled with sediments from 8 sites. Overall, the concentrations of only 37 percent of the 6,776 analyses of the 121 water samples were greater than the reporting limit. Selenium, bismuth, chromium, niobium, silver, and zirconium were not detected in any water samples. The percentage of concentrations for the water samples that were above the reporting limit ranged from 14 percent for the lanthanide and actinide elements to 77 percent for the alkali and alkaline earth elements. Concentrations were greater than reporting limits in only 23 percent of the analyses of reservoir water and 29 percent of the analyses of reservoir water overlying incubation cores. In contrast, 47 and 48 percent of the concentrations of porewater and water samples tumbled with sediments, respectively, were greater than the reporting limit.

Washington↗
USGS2007

A Roundtable on a National Framework for Natural Hazard Risk Reduction and Management: Developing a Research AgendaSummary Report

Introduction This report summarizes discussion at the Roundtable on a National Framework for Risk Reduction and Management held on November 15, 2006, at the Cosmos Club in Washington, D.C. The Roundtable was cosponsored by the U.S. Geological Survey (USGS), the Association of American Geographers (AAG), and The Wharton School, University of Pennsylvania. Comments made by speakers not affiliated with the USGS do not necessarily reflect the positions of the USGS.

Open-File Report↗
USGS2007

Assessment of groundwater input and water quality changes impacting natural vegetation in the Loxahatchee River and floodplain ecosystem, Florida

The Loxahatchee River and Estuary are small, shallow, water bodies located in southeastern Florida. Historically, the Northwest Branch (Fork) of the Loxahatchee River was primarily a freshwater system. In 1947, the river inlet at Jupiter was dredged for navigation and has remained permanently open since that time. Drainage patterns within the basin have also been altered significantly due to land development, road construction (e.g., Florida Turnpike), and construction of the C-18 and other canals. These anthropogenic activities along with sea level rise have resulted in significant adverse impacts on the ecosystem over the last several decades, including increased saltwater encroachment and undesired vegetation changes in the floodplain. The problem of saltwater intrusion and vegetation degradation in the Loxahatchee River may be partly induced by diminished freshwater input, from both surface water and ground water into the River system. The overall objective of this project was to assess the seasonal surface water and groundwater interaction and the influence of the biogeochemical characteristics of shallow groundwater and porewater on vegetation health in the Loxahatchee floodplain. The hypothesis tested are: (1) groundwater influx constitutes a significant component of the overall flow of water into the Loxahatchee River; (2) salinity and other chemical constituents in shallow groundwater and porewater of the river floodplain may affect the distribution and health of the floodplain vegetation.

Florida↗
USGS2011

Water and rock geochemistry, geologic cross sections, geochemical modeling, and groundwater flow modeling for identifying the source of groundwater to Montezuma Well, a natural spring in central Arizona

The National Park Service (NPS) seeks additional information to better understand the source(s) of groundwater and associated groundwater flow paths to Montezuma Well in Montezuma Castle National Monument, central Arizona. The source of water to Montezuma Well, a flowing sinkhole in a desert setting, is poorly understood. Water emerges from the middle limestone facies of the lacustrine Verde Formation, but the precise origin of the water and its travel path are largely unknown. Some have proposed artesian flow to Montezuma Well through the Supai Formation, which is exposed along the eastern margin of the Verde Valley and underlies the Verde Formation. The groundwater recharge zone likely lies above the floor of the Verde Valley somewhere to the north or east of Montezuma Well, where precipitation is more abundant. Additional data from groundwater, surface water, and bedrock geology are required for Montezuma Well and the surrounding region to test the current conceptual ideas, to provide new details on the groundwater flow in the area, and to assist in future management decisions. The results of this research will provide information for long-term water resource management and the protection of water rights.

Arizona↗
USGS2011

Impact of mine and natural sources of mercury on water, sediment, and biota in Harley Gulch adjacent to the Abbott-Turkey Run mine, Lake County, California

Executive Summary Stable-isotope data indicate that there are three sources of water that effect the composition and Hg concentration of waters in Harley Gulch: (1) meteoric water that dominates water chemistry during the wet season; (2) thermal water effluent from the Turkey Run mine that effects the chemistry at sample site HG1; and (3) cold connate groundwater that dominates water chemistry during the dry season as it upwells and reaches the surface. The results from sampling executed for this study suggest four distinct areas in Harley Gulch: (1) the contaminated West Fork of Harley Gulch, consisting of the stream immediately downstream from the mine area and the wetlands upstream from Harley Gulch canyon (sample sites HG1-HG2, (2) the East Fork of Harley Gulch, where no mining has occurred (sample site HG3), (3) sample sites HG4-HG7, where a seasonal influx of saline groundwater alters stream chemistry, and (4) sample sites HG7-HG10, downstream in Harley Gulch towards the confluence with Cache Creek. West Fork: Mine Area and Wetlands The concentration of Hg in both storm sediment and active channel sediment was highest at sample site HG1, immediately downstream from the mine. The highest concentrations of total Hg (Hg T ) in water also occurred at site HG1, and they decreased systematically downstream from the mine. The high concentration of HgT at site HG1 reflects input of thermal-water effluent from the Turkey Run mine which comprises most of the flow at this site during the dry season. During the May 2011 low-flow sampling, Hg T concentration was very high at site HG1, but the maximum in HgT concentration occurred at sample site HG1.5 in the middle of the wetland area. The high concentration of Hg T and isotopic chemistry at this site indicates that a significant input of connate groundwater into the creek at this location contributes to the high Hg concentration in water. At site HG1, just downstream from the thermal water input from the Turkey Run mine, water sampled in June 2010 was almost entirely composed of thermal-water effluent. During the storm sampling in March 2011, which resulted in the highest flows of the winter, thermal effluent was virtually undetectable at site HG1, and the water was all meteoric. During the May 2011 sampling event, the input of connate groundwater in the middle of the wetland area at site HG1.5 was dominant. Discharge from the adit and runoff from the mine contributes to the high Hg concentration at site HG1 under both high and low-flow conditions. East Fork: Background Hg levels in waters collected from the East Fork of Harley Gulch, where no mining has occurred, were as high as 32.8 parts per trillion (pptr). These levels of Hg in water are significantly higher than regional background Hg concentrations, which range from 4-7 pptr. These anomalous Hg concentrations are partially explained by the abundance of Hg-enriched groundwater in Harley Gulch. Sites HG4-HG7 Downstream from the wetland, the aqueous concentration of HgT decreased, but remained above background levels as another input of connate groundwater occurs in the creek segment between sample sites HG4 and HG7. The input of connate groundwater in this segment of the creek is reflected in the increase in dissolved constituents characteristic of the connate groundwater, such as sulfate (SO4), chloride (Cl) and magnesium (Mg). Stable-isotope data for heavy isotopes d18O and d2D also confirm two areas of input of connate groundwater into Harley Gulch: the creek segment in the West Fork near sample site HG1.5 and the segment between sample sites HG4 and HG7. Downstream from the second area of input of connate groundwater, both HgF and Hg T concentrations decrease similarly, but the percentage of Hg in the filtered fraction increases. The decreases in HgT and HgF between sample sites HG5 and HG7 suggests that this second source of connate groundwater to Harley Gulch is distinct from the Hg-enriched source that enters the middle of the wetlands at sample site HG1.5. During low-flow conditions in June 2010, input of connate groundwater increased from sample site HG4 and reached a maximum near sample site HG7, where it dominated creek water chemistry. Waters collected from sample site HG7 during the June 2010 sampling event were the heaviest isotopically and contained high concentrations of Cl and SO4, constituents that are characteristically high in the connate groundwater. Both above and below sample site HG7, the amount of connate groundwater in the creek water decreased. Sites HG8-HG10 Sediment with high Hg concentration is present throughout the West Fork of Harley Gulch below the mine and in the upper part of the Harley Gulch main stem to just above sample site HG10. At the sample site furthest downstream, HG10, Hg concentration is at background levels, as are cobalt (Co), nickel (Ni), and tungsten (W), indicating that the sediment is not significantly contaminated with Hg from the mine.

California↗
USGS2015

Proceedings of the 9th U.S.-Japan natural resources panel for earthquake research

Introduction The UJNR Panel on Earthquake Research promotes advanced study toward a more fundamental understanding of the earthquake process and hazard estimation. The Ninth Joint meeting was extremely beneficial in furthering cooperation and deepening understanding of problems common to both the U.S. and Japan. The meeting included productive exchanges of information on approaches to systematic observation and modeling of earthquake processes. Regarding the earthquake and tsunami of March 2011 off the Pacific coast of Tohoku, the Panel recognizes that further efforts are necessary to achieve our common goal of reducing earthquake risk through close collaboration and focused discussions at the 10th UJNR meeting. We look forward to continued cooperation on issues involving the densification of observation networks and the open exchange of data among scientific communities. We recognize the importance of making information publicly available in a timely manner. We also recognize the importance of information exchange on research policy and strategies, including the frameworks of research organizations. Areas of Cooperation –Specific areas of earthquake research where cooperative research between the U.S. and Japan may lead to significant advancement include, but are not limited to: –Probabilistic earthquake and tsunami hazard estimation, including extraordinarily large earthquakes, both in our respective countries and worldwide, incorporating knowledge of current and past behavior, and physics based computational models; –Real-time information from seismic, geodetic and strain measurements, including borehole strainmeters and seafloor observations using offshore cabled networks; –Technologies for measuring crustal deformation; –Early warning technologies for earthquakes and tsunamis; Studies of recurrence of large and extraordinary large earthquakes using paleoseismic, paleotsunami, geodetic and seismic methods; –Laboratory, theoretical and in situ studies of fault-zone processes; –Studies of episodic tremor and slow slip events using seismic, geodetic, and borehole strain measurements, and simulation techniques; –Systematic studies of earthquake predictability through rigorously evaluated scientific prediction experiments and robust databases; –Studies of near-source ground motions, geological effects and the response of engineered structures. The Panel strongly urges that the appropriate agencies in the U.S. and Japan that are represented on this panel work together with the academic sector to support and coordinate scientific work in these areas of cooperation. The Panel recognizes the importance of promoting the exchange of scientific personnel, exchange of data, and fundamental studies to advance progress in earthquake research. The U.S. and Japan should promote these exchanges throughout the world. The Panel endorses continuation of these activities.

Open-File Report↗
USGS2016

LANDFIRE 2010—Updates to the national dataset to support improved fire and natural resource management

The Landscape Fire and Resource Management Planning Tools (LANDFIRE) 2010 data release provides updated and enhanced vegetation, fuel, and fire regime layers consistently across the United States. The data represent landscape conditions from approximately 2010 and are the latest release in a series of planned updates to maintain currency of LANDFIRE data products. Enhancements to the data products included refinement of urban areas by incorporating the National Land Cover Database 2006 land cover product, refinement of agricultural lands by integrating the National Agriculture Statistics Service 2011 cropland data layer, and improved wetlands delineations using the National Land Cover Database 2006 land cover and the U.S. Fish and Wildlife Service National Wetlands Inventory data. Disturbance layers were generated for years 2008 through 2010 using remotely sensed imagery, polygons representing disturbance events submitted by local organizations, and fire mapping program data such as the Monitoring Trends in Burn Severity perimeters produced by the U.S. Geological Survey and the U.S. Forest Service. Existing vegetation data were updated to account for transitions in disturbed areas and to account for vegetation growth and succession in undisturbed areas. Surface and canopy fuel data were computed from the updated vegetation type, cover, and height and occasionally from potential vegetation. Historical fire frequency and succession classes were also updated. Revised topographic layers were created based on updated elevation data from the National Elevation Dataset. The LANDFIRE program also released a new Web site offering updated content, enhanced usability, and more efficient navigation.

Open-File Report↗
USGS2017

Proceedings of the 11th United States-Japan natural resources panel for earthquake research, Napa Valley, California, November 16–18, 2016

The UJNR Panel on Earthquake Research promotes advanced research toward a more fundamental understanding of the earthquake process and hazard estimation. The Eleventh Joint meeting was extremely beneficial in furthering cooperation and deepening understanding of problems common to both Japan and the United States. The meeting included productive exchanges of information on approaches to systematic observation and modeling of earthquake processes. Regarding the earthquake and tsunami of March 2011 off the Pacific coast of Tohoku and the 2016 Kumamoto earthquake sequence, the Panel recognizes that further efforts are necessary to achieve our common goal of reducing earthquake risk through close collaboration and focused discussions at the 12th UJNR meeting.

Open-File Report↗
USGS2020

Supporting natural resource-management decisions — The role of economics at the U.S. Department of the Interior (DOI) — 2018 DOI Economics Training Workshop

The second U.S. Department of the Interior (DOI) Economics Training Workshop (hereafter “Workshop”) was held during September 25–27, 2018, in Washington, D.C., to identify, highlight, and better understand needs and opportunities for economic analysis to support DOI’s mission. Building on the first workshop in 2017, the second Workshop, jointly convened by the DOI Office of Policy Analysis and the U.S. Geological Survey (USGS) Science and Decisions Center, provided an opportunity for DOI economists to share expertise and experiences and to build collaboration and communication channels across DOI. In addition, the second Workshop provided training sessions on a variety of relevant economic and modeling topics. More than 40 DOI economists gathered at the Workshop to share their work, discuss shared challenges, and identify approaches to advance the use and contribution of economics at the DOI.

Open-File Report↗