953 research outputs found
An environmental assessment of the John Pennekamp Coral Reef State Park and the Key Largo Coral Reef Marine Sanctuary (Unpublished 1983 Report)
The Pennekamp Coral Reef State Park was established in 1960 and the Key Largo National Marine Sanctuary in 1975. Field studies, funded by NOAA, were conducted in 1980 - 1981 to
determine the state of the coral reefs and surrounding areas in relation to changing environmental conditions and resource management that had occurred over the intervening
years. Ten reef sites within the Sanctuary and seven shallow grass and hardbottom sites within the Park were chosen for qualitative and quantitative studies. At each site, three parallel transects not less than 400 m long were run perpendicular to the reef or shore, each 300 m
apart. Observations, data collecting and sampling were done by two teams of divers. Approximately 75 percent of the bottom within the 18-m isobath was covered by marine
grasses, predominantly turtle grass. The general health of the seagrasses appeared good but a few areas showed signs of stress. The inner hardbottom of the Park was studied at the two entrances to Largo Sound. Though at the time of the study the North Channel hardbottom was subjected to only moderate boat traffic, marked changes had taken place over the past years, the most obvious of which was the loss of the extensive beds of Sargassum weed, one of the most extensive beds of this alga in the Keys. Only at this site was the green alga Enteromorpha encountered. This alga, often considered a pollution indicator, may denote the effects of shore run off. The hardbottom at South Channel and the surrounding grass beds showed signs of stress. This area bears the heaviest boat traffic within the Park waters causing continuous turbidity from boat wakes with resulting siltation. The offshore hardbottom and rubble areas in
the Sanctuary appeared to be in good health and showed no visible indications of deterioration. Damage by boat groundings and anchors was negligible in the areas surveyed. The outer reefs in general appear to be healthy. Corals have a surprising resiliency to detrimental factors and, when conditions again become favorable, recover quickly from even severe damage. It is, therefore, a cause for concern that Grecian Rocks, which sits somewhat inshore of the outer reef line, has yet to recover from die-off in 1978. The slow recovery, if occurring, may be due to the lower quality of the inshore waters. The patch reefs, more adapted to inshore waters, do not show obvious stress signs, at least those surveyed in this study. It is apparent
that water quality was changing in the keys. Water clarity over much of the reef tract was observed to be much reduced from former years and undoubtedly plays an important part in the stresses seen today over the Sanctuary and Park. (PDF contains 119 pages
Octopus rapanui, new species, from Easter Island (Cephalopoda: Octopoda)
Octopus rapanui, new species, is described from Easter Island. It is distinguished from other Indo-Pacific species by a combination
of characters including the shape of the lower mandibular rostrum, long rachidian radular teeth, large secondary diverticulum of the penis and long, slender posterior salivary glands
Loligo stearnsii hemphill, 1982(mollusca, cephalopoda): Request for suppression under the plenary powers z.n.(s.)2041
The biogeography of the deep-sea octopoda
The deep-sea octopods are in both octopod suborders, the Cirrata with three families, eight genera and 29 species, and the Incirrata with three octopodid subfamilies, 11 genera and 48 species. In addition, some families in the Incirrata contain deep-sea pelagic species. Only benthic or "near benthic" species are dealt with in this paper. Among the Cirrata, only the Cirroteuthidae contain species with a multi-ocean distribution. Cirrothauma murrayi is possibly cosmopolitan, occuring from polar seas to the depths of the tropics. Cirroteuthis muelleri has an amphiboreal distribution in the North Atlantic and North Pacific. In the monotypic Stauroteuthidae, Stauroteuthis syrtensis is known only from the temperate western North Atlantic. The Opisthoteuthidae are represented by two genera. Opisthoteuthis with 10 species is the shallowest-dwelling of the cirrates, with all but three species living between 100 and 1000m. The genus is distributed throughout the oceans except in high latitudes. Grimpoteuthis, with 13 species, occurs in all oceans but no species is recorded from more than one ocean. A specimen has been trawled from 7279m.
The deep-sea Incirrata are found among three subfamilies of the Octopodidae. In the Bathypolypodinae, Bathypolypus has five species in the Atlantic, one off Japan, one in the Indian Ocean; Teretoctopus has two species in the Indian Ocean, and Benthoctopus has approximately 15 species distrubuted worldwide from the Antarctic to the Arctic, with individual species restricted to single oceans. Among the Pareledoninae, Pareledone, Vosseledeone and Velodona are found only in the southern hermisphere, and Tetracheledone only in the western North Atlantic. Pareledone is the most speciose and has a circum-Antarctic distribution; the monotypic Vosseledone is known only from Brazil; the two species of Velodona occur of East Africa. Among the Graneledoninae, Graneledone has two species in the Southern Ocean, one in the North Atlantic, one in the North pacific and one in the Panamic region. Thaumeledone and Bentheledone are confined to the Southern Ocean
Squid Resources of the Gulf of Mexico and Southeast Atlantic Coasts of the United States
Five species of commercially important squid occur in the southeastern fisheries region of the United States, which includes the northern Gulf of Mexico and the Atlantic coast south of Cape Hatteras. These are Lo/igo pealei, Doryteuthis plei, Lolliguncula brevis, IIlex illecebrosus and I. coindeti, although the last two species are usually not separated in the reported catches due to difficulty of identification. Although there is considerable overlap in the distributions, the species exhibit somewhat different seasonal patterns of distribution as well as differences in depth and temperature preferences. With the exception of Lolliguncula brevis which inhabits the shallow inshore waters, major concentrations appear to be associated with topographic features such as the Charleston Bump, which cause upwellings of nutrient-rich waters, or with the nutrient-laden water around the delta of the Mississippi River. Anecdotal information from surveys and commercial fishermen supports the existence of substantial stocks of squid in the Gulf of Mexico and along the Atlantic coast from southern Florida to Cape Hatteras
A Review of the Squid Resources of the Southeast Fisheries Region of the United States
The six species of commercially important squid in the Southeastern Fisheries Region, (Loligo pealei, Dorytheuthis plei, Lolliguncula brevis, Illex illecebrosus, I. coindeti and I. oxygonius) show separate seasonal distribution patterns and depth and temperature preferences. With the exception of Lolliguncula brevis, major concentrations are associated with topographic features which cause upwellings, such as the Charleston Bump, and resulting nutrient rich waters or nutrient laden waters around the delta of the Mississippi River. Anecdotal information from surveys and commercial fishermen support the presence of considerable stocks of squid in the Gulf of Mexico and along the Atlantic coasts of Florida and the Carolinas
Harmonized bionomenclature â a recipe for disharmony
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149734/1/tax05035.pd
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal
Standalone vertex ďŹnding in the ATLAS muon spectrometer
A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at âs = 7 TeV collected with the ATLAS detector at the LHC during 2011
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