Skip to main content
U.S. flag

An official website of the United States government

Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16740

Marsh birds and the North American Breeding Bird Survey: judging the value of a landscape level survey for habitat specialist species with low detection rates Marsh birds and the North American Breeding Bird Survey: judging the value of a landscape level survey for habitat specialist species with low detection rates

The North American Breeding Bird Survey was started in 1966, and provides information on population change for >400 species of birds. it covers the continental United States, Canada, and Alaska, and is conducted once each year, in June, by volunteer observers. A 39.4 kIn roadside survey route is driven starting 30 min before sunrise, and a 3 min point count is conducted at each of 50...
Authors
J.R. Sauer

Responsiveness of gill Na+/K+-ATPase to cortisol is related to gill corticosteroid receptor concentrations in juvenile rainbow trout Responsiveness of gill Na+/K+-ATPase to cortisol is related to gill corticosteroid receptor concentrations in juvenile rainbow trout

A positive relationship between receptor concentration and tissue responsiveness is an often-assumed and rarely tested principle in endocrinology. In salmonids, seasonal changes in levels of plasma cortisol and gill corticosteroid receptors (CRs) during the spring indicate a potential role for this hormone in the parr–smolt transformation. It is not known whether these seasonal changes...
Authors
J. M. Shrimpton, S. D. McCormick

Biogenic silica from the BDP93 drill site and adjacent areas of the Selenga Delta, Lake Baikal, Siberia Biogenic silica from the BDP93 drill site and adjacent areas of the Selenga Delta, Lake Baikal, Siberia

Biogenic silica contents of sediments on the lower Selenga Delta and Buguldeika saddle in Lake Baikal show distinct fluctuations that reflect changes in diatom productivity, and ultimately, climate. The pattern of the upper 50 m of the section, dating from about 334 ka, is similar to that of the marine oxygen-isotope record, increasingly so as the younger sediments become progressively...
Authors
Steven M. Colman, John A. Peck, Josephine Hatton, Eugene B. Karabanov, John W. King

Formation of natural gas hydrates in marine sediments 1. Conceptual model of gas hydrate growth conditioned by host sediment properties Formation of natural gas hydrates in marine sediments 1. Conceptual model of gas hydrate growth conditioned by host sediment properties

The stability of submarine gas hydrates is largely dictated by pressure and temperature, gas composition, and pore water salinity. However, the physical properties and surface chemistry of deep marine sediments may also affect the thermodynamic state, growth kinetics, spatial distributions, and growth forms of clathrates. Our conceptual model presumes that gas hydrate behaves in a way...
Authors
M. B. Clennell, M. Hovland, J.S. Booth, P. Henry, W.J. Winters

Dynamic replacement and loss of soil carbon on eroding cropland Dynamic replacement and loss of soil carbon on eroding cropland

Links between erosion/sedimentation history and soil carbon cycling were examined in a highly erosive setting in Mississippi loess soils. We sampled soils on (relatively) undisturbed and cropped hillslopes and measured C, N, 14C, and CO2 flux to characterize carbon storage and dynamics and to parameterize Century and spreadsheet 14C models for different erosion and tillage histories. For...
Authors
J.W. Harden, J. M. Sharpe, W.J. Parton, D.S. Ojima, T. L. Fries, Thomas G. Huntington, S. M. Dabney

Characterizing backcountry camping impacts in Great Smoky Mountains National Park Characterizing backcountry camping impacts in Great Smoky Mountains National Park

This investigates resource impacts on backcounty campsites in the Great Smoky Mountains National Park, USA. Study objectives were to enhance our understanding of camping impacts and to improve campsite impact assessment procedures by means of multivariate techniques. Three-hundred and eight campsites at designated backcountry campgrounds, and 69 additional unofficial campsites were...
Authors
Y.-F. Leung, J. L. Marion

Forest area and distribution in the Mississippi alluvial valley: Implications for breeding bird conservation Forest area and distribution in the Mississippi alluvial valley: Implications for breeding bird conservation

Knowing the current forest distribution and patch size characteristics is integral to the development of geographically defined, habitat-based conservation objectives for breeding birds. Towards this end, we classified 2.6 million ha of forest cover within the Mississippi Alluvial Valley using 1992 thematic mapper satellite imagery. Although historically this area, from southern Illinois...
Authors
D.J. Twedt, C.R. Loesch
Was this page helpful?