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The U.S. Geological Survey (USGS) has developed climate indices, referred to as bioclimatic predictors, which highlight climate conditions best related to species physiology. A set of 20 bioclimatic predictors were developed as Geographic Information Systems (GIS) continuous raster surfaces for each year between 1895 and 2009. The Parameter-elevation Regression on Independent Slopes Model (PRISM) and down-scaled PRISM data, which included both averaged multi-year and averaged monthly climate summaries, was used to develop these multi-scale bioclimatic predictors. Bioclimatic predictors capture information about annual conditions (annual mean temperature, annual precipitation, annual range in temperature and precipitation), as well as seasonal mean climate conditions and intra-year seasonality (temperature of the coldest and warmest months, precipitation of the wettest and driest quarters). Examining climate over time is useful when quantifying the effects of climate changes on species' distributions for past, current, and forecasted scenarios. These data, which have not been readily available to scientists, can provide biologists and ecologists with relevant and multi-scaled climate data to augment research on the responses of species to changing climate conditions. The relationships established between species demographics and distributions with bioclimatic predictors can inform land managers of climatic effects on species during decisionmaking processes.
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Two U.S. Geological Survey National Hydrologic Benchmark stations--Young Womans Creek near Renovo, Pennsylvania and Esopus Creek at Shandaken, New York--were studied to (1) define, both areally and temporally, variations of stream acidity and other water quality characteristics within the basins; (2) evaluate how well the data collected at the Benchmark station represent the water quality conditions upstream; (3) define relations between streamflow acidity or pH; and (4) provide a data base to detect trends in quality of headwater streams. Samples were collected at nine sites, including the Benchmark station, in each basin for three series of measurements over a range of streamflows. Along with streamflow, samples were analyzed for water temperature, specific conductance, pH, dissolved oxygen, acidity, alkalinity, dissolved sulfate, and dissolved nitrite plus nitrate. The results of the measurements indicated little water quality variation in the Young Womans Creek basin. Therefore, the data collected at the Benchmark station can be used to reflect upstream changes in water quality. The data collected at the Esopus Creek station did not reflect upstream conditions as well as the Young Womans Creek data because the water quality varied throughout the basin. Few strong relations were found between streamflow and the water quality characteristics examined in this study. The Esopus Creek data indicated the possibility of relationships between streamflow and alkalinity, dissolved nitrite plus nitrate, and specific conductance. No relations were found between streamflow and the Young Womans Creek water quality data. (USGS)
The U.S. Geological Survey used four programs in 1990 to provide external data quality assurance for the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Results of the intersite- comparison program indicate that 80 and 74 percent of the site operators met the NADP/NTN goals for pH determination and 98 and 95 percent of the site operators met the NADP/NTN goals for specific- conductance determination during the two studies in 1990. The effects of routine sample handling, processing, and shipping determined in the blind-audit program indicated significant positive bias for calcium, magnesium, sodium, potassium, chloride, nitrate, and sulfate. Significant negative bias was determined for hydrogen ion and specific conductance. A Kruskal-Wallis test indicated that there were no significant (a=0.01) differences in analytical results from the three laboratories participating in the interlaboratory-comparison program. Results from the collocated-sampler study indicate the median relative error for potassium and ammonium concentration and deposition exceeded 15 percent at most sites while the median relative error for sulfate and nitrate at all sites was less than 6 percent for concentration and was less than 15 percent for deposition.
This survey was initiated in 1966 as a project of a subcommittee of the A.O.U.'s Committee on Research, at that time chaired by Paul H. Baldwin. The subcommittee consisted of the authors and Ralph J. Raitt. In 1968 the project was separated from the Committee on Research and the temporary Committee on Collections was established, with the present authors as its members. This paper is the final report of the committee. In the past, many studies utilizing museum materials have been handicapped by ignorance of the existence of potentially important specimens. We hoped, by means of this survey, to enable future workers to take full advantage of all available material. The objectives of the survey were to determine the locations of collections of ornithological material with research potential, particularly skins, skeletons, fluid-preserved specimens, eggs, and nests; to assess the sizes and particular geographic or systematic strengths of the various collections; to locate former private collections; to learn what collections include holotypes, and who is responsible for the collections. These basic points are generally well-known for the larger institutions that specialize in maintaining research collections, but not for many smaller collections containing valuable material. The survey was inspired by and patterned after a series made of mammal collections (see Anderson et al. 1963, J. Mammal. 44: 471-500).
The US Geological Survey (USGS) is preparing new seismic national maps for release in April 1996. The new maps plot probabilistic ground motions for return times of about 500, 1000, and 2500 years. Deterministic (scenario) ground-motion maps are being prepared for selected faults in the western US. Due to the diversity of tectonic settings in the US, mapping methodologies for different regions had to be modified. A four-model approach is used to eliminate the need for drawing seismic source zones to determine seismic activity levels. A logic tree approach is used to incorporate alternative models of seismic hazard and alternative relations of seismic attenuation.
The US Geological Survey, US Department of Agriculture, and US Environmental Protection Agency are conducting research and regional assessments in support of policy alternatives intended to protect water resources from agricultural chemical contamination. The mid-continent was selected because of the intense row crop agriculture and associated herbicide application in this region. An application of a geographic information system is demonstrated for analyzing and comparing the distribution of estimated atrazine use to the detection rate of atrazine in groundwater. Understanding the relations between atrazine use and detection in groundwater is important in policy deliberations to protect water resources. Relational analyses between measures of chemical use and detection rate by natural resource units may provide insight into critical factors controlling the processes that result in groundwater contamination from agricultural chemicals.
The rapid growth in the use of Geographic Information Systems (GIS) has highlighted the need for regional and national scale digital geologic maps that have standardized information about geologic age and lithology. Such maps can be conveniently used to generate derivative maps for manifold special purposes such as mineral-resource assessment, metallogenic studies, tectonic studies, and environmental research. Although two digital geologic maps (Schruben and others, 1994; Reed and Bush, 2004) of the United States currently exist, their scales (1:2,500,000 and 1:5,000,000) are too general for many regional applications. Most states have digital geologic maps at scales of about 1:500,000, but the databases are not comparably structured and, thus, it is difficult to use the digital database for more than one state at a time. This report describes the result for a seven state region of an effort by the U.S. Geological Survey to produce a series of integrated and standardized state geologic map databases that cover the entire United States. In 1997, the United States Geological Survey's Mineral Resources Program initiated the National Surveys and Analysis (NSA) Project to develop national digital databases. One primary activity of this project was to compile a national digital geologic map database, utilizing state geologic maps, to support studies in the range of 1:250,000- to 1:1,000,000-scale. To accomplish this, state databases were prepared using a common standard for the database structure, fields, attribution, and data dictionaries. For Alaska and Hawaii new state maps are being prepared and the preliminary work for Alaska is being released as a series of 1:250,000 scale quadrangle reports. This document provides background information and documentation for the integrated geologic map databases of this report. This report is one of a series of such reports releasing preliminary standardized geologic map databases for the United States. The data products of the project consist of two main parts, the spatial databases and a set of supplemental tables relating to geologic map units. The datasets serve as a data resource to generate a variety of stratigraphic, age, and lithologic maps. This documentation is divided into four main sections: (1) description of the set of data files provided in this report, (2) specifications of the spatial databases, (3) specifications of the supplemental tables, and (4) an appendix containing the data dictionaries used to populate some fields of the spatial database and supplemental tables.
Water resources data in this volume for the 1981 water year consists of records of stage discharge, and water quality of streams and wells; stage, contents, and water quality in lakes and reservoirs; and water levels in wells. This report contains discharge records for 162 gaging stations; stage and contents for 12 lakes and reservoirs; water quality for 63 stations and 27 wells; water levels for 78 observation wells. Also included are 1 low-flow partial-record station and 32 water quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.
Volume 2 of water resources data for the 1980 water year for California consists of records of stage, discharge, and water quality of streams and wells; stage, contents, and water quality in lakes and reservoirs; and water levels in wells. This report contains discharge records for 159 gaging stations; stage and contents for 19 lakes and reservoirs; water quality for 116 stations and 32 wells; water levels for 85 observation wells. Also included are 4 crest-stage partial-record stations and 3 low-flow partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.