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Filter Total Items: 3377

USGS reports latest land-water changes for southeastern Louisiana

The USGS National Wetlands Research Center is reporting that a total of 118 square miles of land has been transformed to new water areas in a 9,742 square mile area from the Chandeleur Islands to the Atchafalaya River. This area encompasses the basins of Breton Sound, Mississippi River, Pearl River, Pontchartrain, Barataria, Terrebonne and the western quarter of the Atchafalaya basin.
Authors
John A. Barras, James B. Johnston

Bioindicators from Mosquitofish (Gambusia affinis) Sampled from the Imperial Valley in Southern California

The Sonny Bono Salton Sea National Wildlife Refuge (SSNWR) is located 64 km north of the Mexican border at the southern end of the Salton Sea in California's Imperial Valley. Freshwater ponds and managed habitats at the SSNWR, Calipatria, Calif. are supplied with Colorado River water that carries compounds from upstream sources. Components include municipal and industrial discharges, agricultural
Authors
Jill A. Jenkins, Rassa O. Draugelis-Dale

The Interface Between Theory and Data in Structural Equation Models

Structural equation modeling (SEM) holds the promise of providing natural scientists the capacity to evaluate complex multivariate hypotheses about ecological systems. Building on its predecessors, path analysis and factor analysis, SEM allows for the incorporation of both observed and unobserved (latent) variables into theoretically based probabilistic models. In this paper we discuss the interfa
Authors
James B. Grace, Kenneth A. Bollen

Back to the basics: Lake Tahoe, California /Nevada: Geography and mathematics

Back to the Basics: Lake Tahoe, California/Nevada* continues the Wetland Education Through Maps and Aerial Photography (WETMAAP) Program of exercises on teaching foundational map reading and spatial differentiation skills. It is the third published exercise from the Back to the Basics series developed by the WETMAAP Program. The current exercise modified is from the Lake Tahoe Back to the Basics w
Authors
Lawrence R. Handley, Catherine M. Lockwood, Nathan Handley

Possible effects of the 2004 and 2005 hurricanes on manatee survival rates and movement

Abstract not supplied at this time
Authors
C.A. Langtimm, M. D. Krohn, J. P. Reid, B.M. Stith, C.A. Beck

Relative vulnerability of female turtles to road mortality

Abstract not supplied at this time
Authors
D.A. Steen, M. Aresco, S.G. Beilke, B. Compton, C. K. Dodd, H. Forrester, J.W. Gibbons, J. Greene-McLeod, G. Johnson, T. Langen, M.J. Oldham, D.N. Oxier, R. Sammure, F. Schueler, Jonathan Sleeman, L. L. Smith, J. Tucker, J.P. Gibbs

Possible effects of the 2004 and 2005 hurricanes on manatee survival rates and movement

Abstract not supplied at this time
Authors
C.A. Langtimm, M. D. Krohn, J. P. Reid, B.M. Stith, C.A. Beck

Vanishing before our eyes

No abstract available
Authors
Wylie C. Barrow, William R. Fontenot, Madeline H. Barrow, Richard A. DeMay, David Muth

Evaluation of eelgrass beds mapping using a high-resolution airborne multispectral scanner

Eelgrass (Zostera marina) can provide vital ecological functions in stabilizing sediments, influencing current dynamics, and contributing significant amounts of biomass to numerous food webs in coastal ecosystems. Mapping eelgrass beds is important for coastal water and nearshore estuarine monitoring, management, and planning. This study demonstrated the possible use of high spatial (approximately
Authors
H. Su, D. Karna, E. Fraim, M. Fitzgerald, J. S. Myers, R. Dominguez, B. Coffland, Lawrence R. Handley, T. Mace

A multivariate model of plant species richness in forested systems: Old-growth montane forests with a long history of fire

Recently, efforts to develop multivariate models of plant species richness have been extended to include systems where trees play important roles as overstory elements mediating the influences of environment and disturbance on understory richness. We used structural equation modeling to examine the relationship of understory vascular plant species richness to understory abundance, forest structure
Authors
D.C. Laughlin, J.B. Grace