• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1992.05a
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• pp.9-10
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• 1992

• Korean Journal of Remote Sensing
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• v.27 no.3
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• pp.235-258
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• 2011

The purpose of this study is to investigate climatological variations from the temporal and spatial surface particulate organic carbon (POC) estimates based on SeaWiFS spectral radiance, and to determine the physical mechanisms that affect the distribution of pac in the Gulf of Mexico. 7-year monthly mean values of surface pac concentration (Sept. 1997 - Dec. 2004) were estimated from Maximum Normalized Difference Carbon Index (MNDCI) algorithm using SeaWiFS data. Synchronous 7-year monthly mean values of remote sensing data (sea surface temperature (SST), sea surface wind (SSW), sea surface height anomaly (SSHA), precipitation rate (PR)) and recorded river discharge data were used to determine physical forcing factors. The spatial pattern of POC was related to one or more factors such as river runoff, wind-derived current, and stratification of the water column, the energetic Loop Current/Eddies, and buoyancy forcing. The observed seasonal change in the POC plume's response to wind speed in the western delta region resulted from seasonal changes in the upper ocean stratification. During late spring and summer, the low-density river water is heated rapidly at the surface by incoming solar radiation. This lowers the density of the fresh-water plume and increases the near-surface stratification of the water column. In the absence of significant wind forcing, the plume undergoes buoyant spreading and the sediment is maintained at the surface by the shallow pycnocline. However, when the wind speed increases substantially, wind-wave action increases vertical motion, reducing stratification, and the sediment were mixed downward rather than spreading laterally. Maximum particle concentrations over the outer shelf and the upper slope during lower runoff seasons were related to the Loop Current/eddies and buoyancy forcing. Inter-annual differences of POC concentration were related to ENSO cycles. During the El Nino events (1997-1998 and 2002-2004), the higher pac concentrations existed and were related to high runoffs in the eastern Gulf of Mexico, but the opposite conditions in the western Gulf of Mexico. During La Nina conditions (1999-2001), low Poe concentration was related to normal or low river discharge, and low PM/nutrient waters in the eastern Gulf of Mexico, but the opposite conditions in the western Gulf of Mexico.

• ALGAE
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• v.20 no.1
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• pp.31-36
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• 2005

Scinaia latifrons Howe occurs in rhodolith beds between 9 to 27 m depths at San Lorenzo channel, Gulf of California, Mexico. As very little was known about the morphometrics of this normally temperate species in a subtropical area, we investigated the phenological changes from December 1998 to December 1999. The gametophytic phase of the species was present from late February to late May, which represented a shorter time period to other known species in the genus. Our results suggested that two gametophytic cohorts develop over winter and early spring based on the size class structure of the frond height. Thalli became reproductively mature at a small size (1-2 cm in height) and all the plants were monoecious. Scinaia latifrons at the study location underwent allometric growth, indicated by the lack of correlation between size, width of the plants, or branching patterns.

• The Korean Journal of Petroleum Geology
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• v.4 no.1_2 s.5
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• pp.1-11
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• 1996

Multichannel deep seismic reflection data in the Main Pass area of the northern Gulf of Mexico are interpreted in this study for the stratigraphy and the depositional history. Structural analysis of deep seismic reflection data provides new information on the locations of paleo-shelf margins and the basement. The basement occurs at about $7.5{\cal}km$ depth at the northern end of seismic line LSU-1 in the Mississippi shelf. The Jurassic and early Cretaceous shelf margins occupy approximately the same position, whereas the Oligocene shelf margin occurs about 28 km farther landward. Ten major seismic stratigraphic sequences are identified for the Mesozoic and Cenozoic sed-imentary section. Correlation of sequence boundaries defined in this study with those in other areas of the circum-Gulf region indicates that majo. regional unconformities formed at the mid-Miocene (10.5 Ma), mid-Oligocene (30 Ma), mid-Cretaceous (97 Ma), and top-Jurassic (131 Ma). Three distinct periods a.e recognized in the depositional history of the Main Pass area of the northern Gulf of Mexico: (1) shallow ma.me deposition du.ins the period from the opening of the Gulf to the mid-Cretaceous, (2) deep marine deposition in the Cretaceous to the mid-Oligocene, and (3) shallow marine deposition prevailed since the mid-Oligocene to present. A comparison of depositional rates between the Main Pass area and the Destin Dome area indicates that the northern Gulf of Mexico continental margin was initiated as a terrigenous sediment wedge province in the late Cretaceous.

• 한국해양학회지
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• v.3 no.1
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• pp.8-15
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• 1968

An interesting bacterium (#271) was isolated from the abyssal plain of the Sigsbee Deep of the Gulf of Mexico. The organism exhibits marked polymorphism (baciloid, coryneform and myceloid morphologies) in response to certain cultural conditions. the organism has been observed undergoing reproduction by transverse fission, fragmentation and arthrospore production. The presence of arthrospores indicates the bacterium is a member of the genus Arthrobacter; however, computed affinity coefficients do not confirm this genus. Until further studies have been completed on this isolate the authors are reluctant to place it in a generic group.

• ALGAE
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• v.18 no.1
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• pp.59-63
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• 2003

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.27-27
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• 2001

• The Journal of Fisheries Business Administration
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• v.36 no.2 s.68
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• pp.121-134
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• 2005

In order to evaluate the effectiveness of management measures and to provide policy suggestions for the allocation of total allowable catch between recreational and commercial sectors, the economic value of red grouper recreational fishery in the United States Gulf of Mexico was estimated using a Travel Cost Method(TCM), Due to the characteristic of count data, a Poisson model(PM) and a Negative binomial model(NBM) were used in the TCM. Results of models showed that the NBM was statistically more suitable than the PM since the overdispersion problem occurred in the PM. Results also indicated all signs of the estimated parameters were as expected and were significant, except for a Boat parameter in both models. Based on the results of NBM, the total economic value of the recreational red grouper fishery was estimated to be $\$698.6$ and the value per trip was $\$179.5$. In addition, the total changes in expected consumer surplus due to changes in catch rates was $ \$42.3$.

• Ocean and Polar Research
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• v.25 no.4
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• pp.483-491
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• 2003

Since the red grouper was declared overfished, the Gulf of Mexico Fishery Management Council must prepare a rebuilding plan considering the following alternative management policies: a Total Allowable Catch (TAC), 5-month season closure, 1800-pound trip limit, and a 50-fathom longline boundary. This study was aimed at evaluating the effects of proposed policies for rebuilding the red grouper stock in a 10-year period by developing a bioeconomic model. Under the assumption that the recreation sector was held to its share of TAC (24% of the total quota), the target stock biomass goal was attained in all policies. The NPV was the largest in the 5-month season closure policy if the output price did not fall. There were distributional effects on the different components of the fleets in the 1800-pound trip limit and the 50-fathom longline boundary policy.

• ALGAE
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• v.33 no.3
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• pp.231-241
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• 2018

Genetic continuity of Digenea simplex outside the Atlantic waters remains less studied, despite its long exposure to oriental folk medicine and wide distribution in tropical waters. Mitochondrial COI-5P and plastid rbcL sequences and morphology were investigated for plants from Mexico and additional specimens from Japan. Two new species, Digenea mexicana and Digenea rafaelii, are described for plants that would previously have been recognized as D. simplex in Mexico. D. mexicana grows to 10.5 cm tall and has cylindrical axes, irregular or di-, trichotomous branches, simple to branched determinate branchlets with eight pericentral cells, and tetrasporangia on inflated upper parts of determinate branchlets. It occurs intertidally in Quintana Roo, Yucatan Peninsula. D. rafaelii grows to 5 cm tall and has cylindrical axes, irregular or di-, trichotomous branches, and simple determinate branchlets with ten pericentral cells. It occurs intertidally in the Gulf of California. Both COI-5P and rbcL sequences revealed the genetic discontinuity between D. mexicana and D. rafaelii.