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

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At least 1,243 records · Page 69Linked to original sources
USGS1976

A simplified slope-area method for estimating flood discharges in natural channels

Discharge of a stream may be computed from the slope of the water surface, the cross-sectional area, and an estimate of channel roughness. This, the slope-area method, is widely used to compute flood peak discharges from high-water marks. Reliability of a computed discharge depends largely on the roughness coefficient, which must be estimated. This paper shows that results of comparable accuracy can be obtained from area and slope alone in natural channels; a roughness coefficient is not needed because roughness and slope are related. The estimating equation and suggestions for application of the simplified method are included.

Journal of Research of the U.S. Geological Survey↗
USGS2022

Klamath natural flow study, Upper Klamath Basin groundwater flow model

The purpose of the Upper Klamath Basin Groundwater Flow Model (UKBGFM) is to simulate groundwater conditions in the Upper Klamath Basin under historical and predevelopment conditions. The UKBGFM quantifies estimates of and changes in groundwater levels, storage, pumping, drainage flow to tile drains, evapotranspiration, and flow between the Upper Klamath Basin and neighboring basins. The quantifications of base flow to streams and seepage to and from lakes and reservoirs can be used as inputs to the RiverWare Mass Balance Model (Zagona and others, 2001), a companion model being developed as part of the Klamath Natural Flow Study (KNFS).

California, Oregon↗
USGS2023

Bridging the gap between mathematical biology and undergraduate education using applicable natural resource modeling

Mathematical biology is a wide field of study with many venues that undergraduate students can access through research. However, the topics of study for these students can be overwhelming, and many topics of study yield either only trivial results or abstract outcomes that are nonintuitive and diffcult to understand. We have used natural resource modeling, and more specifically, a partnership between academic researchers and federal scientists, as a bridge between undergraduate research and mathematical biology. Our collaboration is an interdisciplinary team that combines biology, mathematics, and statistics professors with government research scientists. As a team, we have mentored students through opportunities such as a Research Experiences for Undergraduates and other projects. In this article, we provide an overview of how we develop questions for undergraduates and outline two case studies, both of which resulted in peer reviewed journal articles. Last, we describe how we also transfer the results from these undergraduate projects to resource managers so the results may be applied to real world problems.

Letters in Biomathematics↗
USGS2025

Natural capital accounting on forested lands: An application to the Colorado River basin

This paper creates a first set of forest natural capital accounts and demonstrates how these accounts can be integrated with general equilibrium models of the economy. Focusing on the Colorado River Basin, we show that deforestation has direct implications for the forest industry and indirect impacts on the economy through water treatment costs and carbon stock. 327,000 acres of forest are projected to be lost to development by 2100, representing a loss of 1.3 million tons of carbon stored in forests. The direct economic impacts associated with forest loss are estimated to be over $30 million, with $28 million of that coming directly from the value of lost carbon.

Conference Paper↗
USGS2000

Natural remediation in the Great Lakes

Overall, the existence of stricter environmental laws during the last 30 years and a reduction in the manufacturing base in the Great Lakes has resulted in improvement in conditions in harbors, rivers, and nearshore waters. Problems remain, such as the inability to dredge certain harbors and remove sediments because of lack of disposal facilities for contaminated sediments. Because of the wide extent of of contaminated sediments in the Great Lakes, much work remains to be done to document the condition of contaminated areas and the degree to which remediation of these areas is occurring from biotic and abiotic natural processes.

Book chapter↗
USGS1969

Natural history of the King Rail

The King Rail ( Rallus elegans Audubon), largest of North American rails, is indeed an elegant bird, as its Latin name implies. Its striking appearance (fig. I), secretive nature, and association with a variety of wetland habitats make it a favorite of bird students and rail hunters. The King Rail is found in most of the eastern half of North America, from the Atlantic coast to the Great Plains and from the Gulf of Mexico to southern Canada. It is most abundant in the fresh and brackish tidal marshes of the Atlantic and Gulf Coastal Plain, the domestic ricefields of Arkansas, Louisiana, and Texas, and the marshes of southern Florida. It is fairly common in parts of the Midwest Prairie and Great Lakes region. I began my studies of this interesting bird in 1950 in the Arkansas ricefields, and have continued them until 1967, both in the field and in the laboratory.

North American Fauna↗
USGS1999

Diversifying natural resources value measurements: The Trinity River study

An interdisciplinary team set out to establish the economic and social values of the Trinity River in northern California . This information was intended to support the Secretary of the Interior's decision on allocation of Trinity River flows . This team set out to measure the values of Trinity River flows , fishery resources , and rec reation amenities in several different ways . A survey was mailed to users of the Trinity River . This single instrument included economic measures ( willingness - to pay and costs incurred in visiting ) and social - psychological measures ( importance , satisfaction , and water allocation preferences ). A closely related survey measured several of these same values among west coast regional households . The results of these surveys were compiled , and the measured economic and social values were compared . We found that integrating economic and social value information pro vides a greater depth of understanding of the resource's value . In addition , this integration provides a more in - depth understanding through the quantitative and qualitative results that emerge.

Society and Natural Resources↗
USGS2009

Alternative natural gas contract and pricing structures and incentives of the LNG industry

Gas conversion to liquefied gas (LNG) and transport by LNG tankers is one option for meeting expanding gas consumption and for gas traded internationally. This paper examines the impact of the traditional gas contract provisions of indefinite pricing, market out price ceilings, and take‐or‐pay requirements on the profitability of LNG projects in the context of markets characterized by price and quantity uncertainty. Simulation experiments are used to examine and calibrate the effects of those provisions. The results provide guidance to operators, host countries and purchasers in structuring such contracts. The paper also assesses prospects of future expansion of world LNG capacity.

Natural Resources Forum↗
USGS2003

Recovery of prairie fish assemblages at the transition from channelized to nonchannelized: Implications for conservation of natural channels

Fish assemblages were systematically sampled along the transition from channelized to unchannelized reaches in seven streams in northern Missouri, USA. Streams ranged in size from 4th to 8th order and were located in the Central Dissected Till Plains including the Grand, Chariton, Salt, and Fabius watersheds. Maximum species richness was reached 3-5 km downstream from the end of channelization. A limited core group of 10 species was present at most of the sites (channelized and unchannelized locations), and a diverse group of 45 species was present at relatively few sites (rarely channelized locations). The core group consisted largely of tolerant, omnivorous species and contained no top carnivores. The 45-species diverse group included a greater proportion of intolerant, benthic invertivorous, lithophilous, and carnivorous species. The effect of channelization extended well into unchannelized reaches and should be considered by conservation planners.

Missouri↗