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Explore WARC's science publications.

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Evaluation of eelgrass beds mapping using a high-resolution airborne multispectral scanner 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...
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 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...
Authors
D.C. Laughlin, J.B. Grace

Assessment of gamete quality for the eastern oyster (Crassostrea virginica) by use of fluorescent dyes Assessment of gamete quality for the eastern oyster (Crassostrea virginica) by use of fluorescent dyes

Evaluation of sperm motility is the single most widely used parameter to determine semen quality in mammals and aquatic species. While a good indicator for fresh sperm viability, post-thaw motility is not always effective at predicting fertilizing ability. Techniques using fluorescent dyes can assess functionality of mammalian sperm, but have not been widely applied in aquatic organisms...
Authors
C. G. Paniagua-Chavez, J. Jenkins, M. Segovia, T.R. Tiersch

Genetic structure of natural and restored shoalgrass Halodule wrightii populations in the NW Gulf of Mexico Genetic structure of natural and restored shoalgrass Halodule wrightii populations in the NW Gulf of Mexico

The decline of seagrass communities worldwide has sparked an urgent need for effective restoration strategies, which require a working knowledge of population genetic structure. Halodule wrighti is a common seagrass of the Caribbean region that is being restored to areas of the Gulf of Mexico, yet little is known of its population genetics. This study provides an assessment of individual...
Authors
S.E. Travis, P. Sheridan

Deep-water antipatharians: Proxies of environmental change Deep-water antipatharians: Proxies of environmental change

Deep-water (307-697 m) antipatharian (black coral) specimens were collected from the southeastern continental slope of the United States and the north-central Gulf of Mexico. The sclerochronology of the specimens indicates that skeletal growth takes place by formation of concentric coeval layers. We used 210Pb to estimate radial growth rate of two specimens, and to establish that they...
Authors
B. Williams, Michael J. Risk, Steve W. Ross, K. J. Sulak

A landscape perspective of the stream corridor invasion and habitat characteristics of an exotic (Dioscorea oppositifolia) in a pristine watershed in Illinois A landscape perspective of the stream corridor invasion and habitat characteristics of an exotic (Dioscorea oppositifolia) in a pristine watershed in Illinois

The spatial distribution of exotics across riparian landscapes is not uniform, and research elaborating the environmental constraints and dispersal behavior that underlie these patterns of distribution is warranted. This study examined the spatial distribution, growth patterns, and habitat constraints of populations of the invasive Dioscorea oppositifolia in a forested stream corridor of...
Authors
J.R. Thomas, B. Middleton, D.J. Gibson

Regional processes in mangrove ecosystems: Spatial scaling relationships, biomass, and turnover rates following catastrophic disturbance Regional processes in mangrove ecosystems: Spatial scaling relationships, biomass, and turnover rates following catastrophic disturbance

Physiological processes and local-scale structural dynamics of mangroves are relatively well studied. Regional-scale processes, however, are not as well understood. Here we provide long-term data on trends in structure and forest turnover at a large scale, following hurricane damage in mangrove ecosystems of South Florida, U.S.A. Twelve mangrove vegetation plots were monitored at...
Authors
G.A. Ward, T. J. Smith, K.R.T. Whelan, T.W. Doyle

Canopy reflectance related to marsh dieback onset and progression in Coastal Louisiana Canopy reflectance related to marsh dieback onset and progression in Coastal Louisiana

In this study, we extended previous work linking leaf spectral changes, dieback onset, and progression of Spartina alterniflora marshes to changes in site-specific canopy reflectance spectra. First, we obtained canopy reflectance spectra (approximately 20 m ground resolution) from the marsh sites occupied during the leaf spectral analyses and from additional sites exhibiting visual signs...
Authors
Elijah W. Ramsey, A. Rangoonwala

Clonal variation in response to salinity and flooding stress in four marsh macrophytes of the northern gulf of Mexico, USA Clonal variation in response to salinity and flooding stress in four marsh macrophytes of the northern gulf of Mexico, USA

Intraspecific variation in stress tolerance can be an important factor influencing plant population structure in coastal wetland habitats. We studied clones of four species of emergent marsh macrophytes native to the northern coast of the Gulf of Mexico in Louisiana, USA, to examine variation in response to salinity and flooding stress under controlled greenhouse conditions. Clones of...
Authors
R.J. Howard, P.S. Rafferty

Influence of propagule flotation longevity and light availability on establishment of introduced mangrove species in Hawai'i Influence of propagule flotation longevity and light availability on establishment of introduced mangrove species in Hawai'i

Although no mangrove species are native to the Hawaiian Archipelago, both Rbizopbora mangle and Bruguiera sexangula were introduced and have become naturalized. Rbizopbora mangle has spread to almost every major Hawaiian island, but B. sexangula has established only on O'ahu, where it was intentionally introduced. To examine the possibility that differences in propagule characteristics...
Authors
J. A. Allen, K. W. Krauss

Water-clover ferns, Marsilea, in the Southeastern United States Water-clover ferns, Marsilea, in the Southeastern United States

A surge in the collection of exotic Marsilea, M. mutica, M. minuta and M. hirsuta in the southeastern United States has prompted the need for updated identification aids. This study provides an annotated key to all water-clover ferns occurring in the region. It describes and illustrates recently documented exotic species and a previously misidentified western introduction. It details the
Authors
Colette C. Jacono, David M. Johnson

Assessment of reproductive effects in largemouth bass (Micropterus salmoides) exposed to bleached/unbleached kraft mill effluents Assessment of reproductive effects in largemouth bass (Micropterus salmoides) exposed to bleached/unbleached kraft mill effluents

This study evaluated the potential effects of different concentrations of bleached/unbleached kraft mill effluent (B/UKME) on several reproductive endpoints in adult largemouth bass (Micropterus salmoides). The kraft mill studied produces a 50/50 mix of bleached/unbleached market pulp with an estimated release of 36 million gal of effluent/day. Bleaching sequences were C90d10EopHDp and...
Authors
M. S. Sepulveda, D. S. Ruessler, N. D. Denslow, S. E. Holm, T. R. Schoeb, T. S. Gross
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