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Explore WARC's science publications.

Filter Total Items: 3543

Plant toxicity, adaptive herbivory, and plant community dynamics Plant toxicity, adaptive herbivory, and plant community dynamics

We model effects of interspecific plant competition, herbivory, and a plant's toxic defenses against herbivores on vegetation dynamics. The model predicts that, when a generalist herbivore feeds in the absence of plant toxins, adaptive foraging generally increases the probability of coexistence of plant species populations, because the herbivore switches more of its effort to whichever...
Authors
Z. Feng, R. Liu, D.L. DeAngelis, Lee C. Bryant, K. Kielland, Chapin F. Stuart, R.K. Swihart

In situ video observations of two manefishes (perciformes: Caristiidae) in the mesopelagic zone of the northern Gulf of Mexico In situ video observations of two manefishes (perciformes: Caristiidae) in the mesopelagic zone of the northern Gulf of Mexico

This paper describes direct video observations of two manefishes, likely Paracaristius sp., from the mesopelagic waters of the north-central Gulf of Mexico. One fish was observed with a remotely operated vehicle at a depth of 829 m by an industrial ROV as part of the SERPENT Project. The second was observed at 496 m from a manned submersible. Little is known about the behavior of...
Authors
M.C. Benfield, John H. Caruso, K. J. Sulak

Production of bovine cloned embryos with donor cells frozen at a slow cooling rate in a conventional freezer (20 C) Production of bovine cloned embryos with donor cells frozen at a slow cooling rate in a conventional freezer (20 C)

Usually, fibroblasts are frozen in dimethyl sulphoxide (DMSO, 10% v/v) at a cooling rate of 1 °C/min in a low-temperature (−80 °C) freezer (LTF) before storage in liquid nitrogen (LN2); however, a LTF is not always available. The purpose of the present study was to evaluate apoptosis and viability of bovine fibroblasts frozen in a LTF or conventional freezer (CF; −20 °C) and their...
Authors
L. Chacon, M.C. Gomez, J.A. Jenkins, S.P. Leibo, G. Wirtu, B.L. Dresser, C.E. Pope

Effects of an invasive plant on a desert sand dune landscape Effects of an invasive plant on a desert sand dune landscape

Given the abundance of non-native species invading wildland habitats, managers need to employ informed triage to focus control efforts on weeds with the greatest potential for negative impacts. Our objective here was to determine the level of threat Sahara mustard, Brassica tournefortii, represents to meeting regional goals for protecting biodiversity. Sahara mustard has spread...
Authors
C.W. Barrows, E.B. Allen, M.L. Brooks, M.F. Allen

Occupancy estimation and the closure assumption Occupancy estimation and the closure assumption

1. Recent advances in occupancy estimation that adjust for imperfect detection have provided substantial improvements over traditional approaches and are receiving considerable use in applied ecology. To estimate and adjust for detectability, occupancy modelling requires multiple surveys at a site and requires the assumption of 'closure' between surveys, i.e. no changes in occupancy...
Authors
Christopher T. Rota, Robert J. Fletcher, Robert M. Dorazio, Matthew G. Betts

Landscape analysis and pattern of hurricane impact and circulation on mangrove forests of the Everglades Landscape analysis and pattern of hurricane impact and circulation on mangrove forests of the Everglades

The Everglades ecosystem contains the largest contiguous tract of mangrove forest outside the tropics that were also coincidentally intersected by a major Category 5 hurricane. Airborne videography was flown to capture the landscape pattern and process of forest damage in relation to storm trajectory and circulation. Two aerial video transects, representing different topographic...
Authors
Thomas W. Doyle, Ken W. Krauss, Christopher J. Wells

Integrated analysis of PALSAR/Radarsat-1 InSAR and ENVISAT altimeter data for mapping of absolute water level changes in Louisiana wetlands Integrated analysis of PALSAR/Radarsat-1 InSAR and ENVISAT altimeter data for mapping of absolute water level changes in Louisiana wetlands

Interferometric Synthetic Aperture Radar (InSAR) has been used to detect relative water level changes in wetlands. We developed an innovative method to integrate InSAR and satellite radar altimetry for measuring absolute or geocentric water level changes and applied the methodology to remote areas of swamp forest in coastal Louisiana. Coherence analysis of InSAR pairs suggested that the...
Authors
J.-W. Kim, Z. Lu, H. Lee, C. K. Shum, C.M. Swarzenski, T.W. Doyle, S.-H. Baek

Coral disease following massive bleaching in 2005 causes 60% decline in coral cover on reefs in the US Virgin Islands Coral disease following massive bleaching in 2005 causes 60% decline in coral cover on reefs in the US Virgin Islands

In the northeast Caribbean, doldrum-like conditions combined with elevated water temperatures in the summer/fall 2005 created the most severe coral bleaching event ever documented within this region. Video monitoring of 100 randomly chosen, permanent transects at five study sites in the US Virgin Islands revealed over 90% of the scleractinian coral cover showed signs of thermal stress by...
Authors
J. Miller, E. Muller, C. Rogers, R. Waara, A. Atkinson, K.R.T. Whelan, M. Patterson, B. Witcher

Site condition, structure, and growth of baldcypress along tidal/non-tidal salinity gradients Site condition, structure, and growth of baldcypress along tidal/non-tidal salinity gradients

This report documents changes in forest structure and growth potential of dominant trees in salt-impacted tidal and non-tidal baldcypress wetlands of the southeastern United States. We inventoried basal area and tree height, and monitored incremental growth (in basal area) of codominant baldcypress (Taxodium distichum) trees monthly, for over four years, to examine the inter...
Authors
K. W. Krauss, J.A. Duberstein, T.W. Doyle, W.H. Conner, Richard H. Day, L.W. Inabinette, J.L. Whitbeck

Hurricane Wilma's impact on overall soil elevation and zones within the soil profile in a mangrove forest Hurricane Wilma's impact on overall soil elevation and zones within the soil profile in a mangrove forest

Soil elevation affects tidal inundation period, inundation frequency, and overall hydroperiod, all of which are important ecological factors affecting species recruitment, composition, and survival in wetlands. Hurricanes can dramatically affect a site's soil elevation. We assessed the impact of Hurricane Wilma (2005) on soil elevation at a mangrove forest location along the Shark River...
Authors
K.R.T. Whelan, T. J. Smith, G.H. Anderson, M.L. Ouellette

Untangling the biological contributions to soil stability in semiarid shrublands Untangling the biological contributions to soil stability in semiarid shrublands

Communities of plants, biological soil crusts (BSCs), and arbuscular mycorrhizal (AM) fungi are known to influence soil stability individually, but their relative contributions, interactions, and combined effects are not well understood, particularly in arid and semiarid ecosystems. In a landscape-scale field study we quantified plant, BSC, and AM fungal communities at 216 locations...
Authors
V. Bala Chaudhary, Matthew A. Bowker, Thomas E. O’Dell, James B. Grace, Andrea E. Redman, Matthias C. Rillig, Nancy C. Johnson

Age, growth, mortality, and reproduction of Roughtongue bass, Pronotogrammus martinicensis 9Serranidae), in the northeastern Gulf of Mexico Age, growth, mortality, and reproduction of Roughtongue bass, Pronotogrammus martinicensis 9Serranidae), in the northeastern Gulf of Mexico

The inaccessibility of outer continental shelf reefs has made it difficult to investigate the biology of Pronotogrammus martinicensis, a small sea bass known to be numerous and widely distributed in such habitat. This study takes advantage of a series of cruises in the northeastern Gulf of Mexico that collected 1,485 individuals. Fish were collected over or in the vicinity of reef...
Authors
Richard S. McBride, Kenneth J. Sulak, Paul E. Thurman, Adam K. Richardson
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