USGS Science⌕ Search

SEARCH · USGS Science

Results for “Fact Sheet”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43Linked to original sources
USGS2001

Nutrients in streams and rivers in the lower Tennessee River basin

Nitrogen and phosphorus are essential nutrients for plant and animal growth, but excessive amounts can promote nuisance growths or “blooms” of algae and other aquatic plants in streams, lakes, and estuaries. In turn, algal blooms can impair the suitability of water for municipal supplies, recreation, fishing, and wildlife. In 1997, the U.S. Geological Survey (USGS) began an assessment of nutrients in the lower Tennessee River Basin as part of the National Water-Quality Assessment (NAWQA) Program. Initial assessments focused on nutrients because officials from Federal, State, and local resource-management and regulatory agencies identified nutrients in surface waters as an issue of concern. In 1996, State water-quality regulatory agencies listed overenrichment of nutrients as the cause of impairment in 37 stream segments and in 2 lakes within the lower Tennessee River Basin. Understanding the relation between the source and transport of nutrients within a watershed can assist resource managers and policymakers in forming sound nutrient-management decisions. This report compares nutrient inputs from nonpoint and point sources and nutrient outputs in selected basins in the lower Tennessee River Basin as summarized from the comprehensive report by Hoos and others (2000), which describes nutrient transport within the lower Tennessee River Basin.

Alabama, Georgia, Kentucky, Mississippi, Tennessee↗
USGS2002

U.S. coral reefs; imperiled national treasures

Coral reefs are home to 25% of all marine species. However, the tiny colonial animals that build these intricate limestone masses are dying at alarming rates. If this trend continues, in 20 years the living corals on many of the world's reefs will be dead and the ecosystems that depend on them severely damaged. As part of the effort to protect our Nation's extensive reefs, U.S. Geological Survey (USGS) scientists are working to better understand the processes that affect the health of these ecologically and economically important ecosystems.

Fact Sheet↗
USGS2003

Native salamanders and introduced fish: Changing the nature of mountain lakes and ponds

During the last century, many fishless mountain lakes and ponds in the Pacific Northwest were stocked with non-native fish, such as brook trout, for recreational purposes. These introduced fish replaced long-toed and northwestern salamander larvae as the top aquatic vertebrate predator by preying on salamander larvae. This predatory interaction has been shown to reduce the abundances of larval salamander populations. We conducted studies in two national parks to assess the abundances of salamander larvae in lakes with and without introduced fish. These studies suggest that the two salamander species were affected quite differently by the presence of introduced fish because of different life-history traits and different distributions of salamanders and fish within each park.

Fact Sheet↗
USGS2000

Mississippi

Explore the source record for details and available documents.

Fact Sheet↗
USGS2001

Assessment of microbiological contamination of the Jacks Fork within the Ozark National Scenic Riverways, Missouri—phase I

The Ozark National Scenic Riverways (ONSR), the Nation's first scenic riverway, was created by an Act of Congress (Public Law 88-492) on August 24, 1964, for "the purpose of conserving and interpreting unique scenic and other natural values and objects of historic interest, including preservation of parts of the Current River and the Jacks Fork River in Missouri as free-flowing streams, preservation of springs and caves, management of wildlife, and provisions for use and enjoyment of the outdoor recreation resources thereof by the people of the United States" (National Park Service, 1981). The primary natural resources protected by the park are 134 miles of the Current and Jacks Fork Rivers. About 1.5 million people visit the ONSR annually to take advantage of excellent recreational opportunities, including canoeing, johnboating, swimming, fishing, tubing, camping, hiking, caving, horseback riding, and hunting.

Fact Sheet↗
USGS2002

Assessment of Undiscovered Oil and Gas Resources of the Uinta-Piceance Province of Colorado and Utah, 2002

The U.S. Geological Survey (USGS) recently completed an assessment of the undiscovered oil and gas potential of the UintaPiceance Province of northwestern Colorado and northeastern Utah (fig. 1). The assessment of the Uinta-Piceance Province is geology based and uses the Total Petroleum System concept. The geologic elements of Total Petroleum Systems include hydrocarbon source rocks (source rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy, petrophysical properties), and hydrocarbon traps (trap formation and timing). Using this geologic framework, the USGS defined five Total Petroleum Systems and 20 Assessment Units within these Total Petroleum Systems, and quantitatively estimated the undiscovered oil and gas resources within each Assessment Unit (table 1).

Colorado, Utah↗
USGS1994

Idaho's surface-water-quality monitoring program: results from five sites sampled during water years 1990-93

In 1990, the U.S. Geological Survey (USGS), in cooperation with the Idaho Department of Health and Welfare, Division of Environmental Quality, implemented a statewide water-quality monitoring program in response to Idaho's antidegradation policy as required by the Clean Water Act. The program objective is to provide water-quality managers with a coordinated statewide network to detect trends in surface-water quality. The monitoring program includes the collection and analysis of samples from 56 sites on the Bear, Clearwater, Kootenai, Pend Oreille, Salmon, Snake, and Spokane Rivers and their tributaries (fig. 1). Samples are collected every year at 5 sites (annual sites) in drainage basins where long-term water-quality management is practiced, every other year at 19 sites (biennial sites) in basins where land and water uses change slowly, and every third year at 32 sites (triennial sites) where future development may affect water quality. Each year, 25 of the 56 sites are sampled. This report discusses results of sampling at five annual sites. During water years 1990-93 (October 1, 1989, through September 30, 1993), samples were collected six times per year at the five annual sites (fig. 1). Onsite analyses were made for discharge, specific conductance, pH, temperature, dissolved oxygen, bacteria (fecal coliform and fecal streptococci), and alkalinity. Laboratory analyses were made for major ions, nutrients, trace elements, and suspended sediment. Suspended sediment, nitrate, fecal coliform, trace elements, and specific conductance were used to characterize surface-water quality. Because concentrations of all trace elements except zinc were near detection limits, only zinc is discussed.

Idaho↗
USGS1997

GeoChange Global Change Data

GeoChange is an online data system providing access to research results and data generated by the U.S. Geological Survey's Global Change Research Program. Researchers in this program study climate history and the causes of climatic variations, as well as providing baseline data sets on contemporary atmospheric chemistry, high-resolution meteorology, and dust deposition. Research results are packaged as data sets, groups of digital files containing scientific observations, documentation, and interpretation. The data sets are arranged in a consistent manner using standard file formats so that users of a variety of computer systems can access and use them.

Fact Sheet↗