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Publications

Explore WARC's science publications.

Filter Total Items: 3361

Aircraft MSS data registration and vegetation classification of wetland change detection

Portions of the Savannah River floodplain swamp were evaluated for vegetation change using high resolution (5a??6 m) aircraft multispectral scanner (MSS) data. Image distortion from aircraft movement prevented precise image-to-image registration in some areas. However, when small scenes were used (200-250 ha), a first-order linear transformation provided registration accuracies of less than or equ
Authors
E.J. Christensen, J.R. Jensen, Elijah W. Ramsey, H.E. Mackey

Habitat islands and the equilibrium theory of island biogeography: testing some predictions

Species-area data from a study of marsh birds are used to test five predictions generated by the equilibrium theory of island biogeography. Three predictions are supported: we found a significant species-area relationship, a non-zero level of turnover, and a variance-mean ratio of 0.5. One prediction is rejected: the extinction rates were not greater on small islands. The results of one test are e
Authors
M. Brown, J.J. Dinsmore

Environmental impacts and regulatory policy. Implications of spray disposal of dredged material in Louisiana wetlands

The capabilities of a new wetland dredging technology were assessed along with associated newly developed state and federal regulatory policies to determine if policy expectations realistically match the technological achievement. Current regulatory practices require amelioration of spoil bank impacts upon abandonment of an oil/gas well, but this may not occur for many years or decades, if at all.
Authors
Donald R. Cahoon, J.H. Cowan

Fuelwood production and use in rural Swaziland: a case-study of two communities

Information of fuelwood consumption and the local production of wood was collected in two small rural communities in Swaziland. Fuelwood consumption was estimated to be 0.77 t persona??1 yeara??1 in one community (Sigombeni), and 0.63 t persona??1 in the other (Bhekinkhosi). Bhekinkhosi was found to be experiencing a significant fuelwood production/consumption deficit and it expected that Sigomben
Authors
J. A. Allen, D.P. Pimentel, J.P. Lasoie

The role of stand history in assessing forest impacts

Air pollution, harvesting practices, and natural disturbances can affect the growth of trees and forest development. To make predictions about anthropogenic impacts on forests, we need to understand how these factors affect tree growth. In this study the effect of disturbance history on tree growth and stand structure was examined by using a computer model of forest development. The model was run
Authors
V.H. Dale, T.W. Doyle

Habitat Suitability Index Models: Black-shouldered kite

A review and synthesis of existing information were used to develop a model for evaluating black-shouldered kite habitat quality. The model is scaled to produce an index between 0 (unsuitable habitat) to 1.0 (optimal habitat). Habitat suitability index models are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for model
Authors
Craig A. Faanes, Rebecca J. Howard

Habitat Suitability Index Models: American alligator

A review and synthesis of existing information were used to develop a model for evaluating American alligator habitat quality. The model is applicable in marshes along the northern Gulf of Mexico. It is scaled to produce an index between 0 (unsuitable habitat) and 1.0 (optimal habitat). Habitat suitability index models are designed for use with the Habitat Evaluation Procedures previously develope
Authors
John D. Newsom, Ted Joanen, Rebecca J. Howard

An oil spill and hazardous waste vulnerability modeling approach (Coastal Louisiana)

No abstract available.
Authors
Floyd O. Stayner, James B. Johnston, James D. Scurry

Measuring the success of wetlands mitigation

No abstract available.
Authors
Millicent L. Quammen

Larval settlement into marine soft-sediment systems: Interactions with the meiofauna

The distribution and abundance of organisms exhibiting complex life cycles, like marine invertebrates, reflect ecological processes operating at all stages in the life history. Few studies have yet considered the mortality patterns of larvae and juveniles. To test whether the permanent meiofauna play a role in macrofaunal larval site-selection, and/or if permanent meiofaunal predators or competito
Authors
Mary C. Watzin