scholarly journals Ictioplancton en la zona portuaria de Limón, Costa Rica

1969 ◽  
pp. 439-442
Author(s):  
Arturo Dominici-Arosemena ◽  
Ernesto Brugnoli-Olivera ◽  
Sylvia Solano-Ulate ◽  
Helena Molina-Ureña ◽  
Ana Rosa Ramírez Coghi
Keyword(s):  
Costa Rica ◽  
Dissolved Oxygen ◽  
Shallow Water ◽  
Sampling Period ◽  
Coastal Areas ◽  
Average Depth ◽  
Common Area ◽  
Chemistry Parameter

Four sampling stations were set 200-500m off Limon Port, Costa Rica, at an average depth of 20 m. From October 1996 to May 1997 horizontal subsuperficial trawls were done for 12 minutes at a speed of about 2KmIh, with a 1 OOO¡.tm plancton neto A total of 28 samples were processed and 104 physieal-chemistry parameter measurements were taken. Average salinity was 30.1 ± 3.7 and dissolved oxygen 6.9 ± 0.6 mg 1-1 reflecting good aeration throughout the sampling périod. This suggests good mixture and a highly dynamic hydrography. Temperature showed no drastic variations (28.0 ± 1.7 OC), possibly because of the constant mixing with shallow water. The highest larval counts were for November and early January and inelude families common to reefs and estuaries (BaJistidae, Lutjanidae) and to coastal areas (Centropomidae, Gerreidae, Haemulidae, Carangidae, Engraulidae, Hemiramphidae, and representative Pleuronectiforrnes) existing in a common area.

scholarly journals Mollusks (Gastropoda and Bivalvia) of the Multiple-Use Reserve Martín García Island, Río de la Plata River: biodiversity and ecology

2012 ◽  
Vol 72 (1) ◽  
pp. 121-130 ◽  
Author(s):  
II César ◽  
SM Martín ◽  
A Rumi ◽  
M Tassara
Keyword(s):  
Dissolved Oxygen ◽  
Water Temperature ◽  
Environmental Variables ◽  
Sampling Period ◽  
Pomacea Canaliculata ◽  
Rio De La Plata ◽  
Multiple Use ◽  
Río De La Plata ◽  
Oxygen Conductivity ◽  
La Plata

The Island of Martin Garcia is located in the Upper Río de la Plata, to the south of mouth the Uruguay River. The aim of the present study was to analyse the biodiversity of the island freshwater mollusks and their relationships to environmental variables. Twelve sampling sites were selected, five were along the littoral section of the island and seven were Inland ponds. Seven major environmental variables were measured: water and air temperature, percentage of oxygen saturation, dissolved oxygen, electrical conductivity, total dissolved solids and pH. Twenty-seven mollusk species were found, Antillorbis nordestensis, Biomphalaria tenagophila tenagophila , B. t. guaibensis, B. straminea, B. peregrina, Drepanotrema kermatoides, D. cimex, D. depressissimum, Chilina fluminea, C. rushii, C. megastoma, Uncancylus concentricus, Hebetancylus moricandi, Stenophysa marmorata, Heleobia piscium, H. parchappii, Potamolithus agapetus, P. buschii, P. lapidum, Pomacea canaliculata, P. megastoma, Asolene platae, Corbicula fluminea, Eupera platensis, Pisidium sterkianum, P. taraguyense and Limnoperna fortunei. UPGMA clustering of species based on their occurrence in different ecological conditions revealed two main species groups. The Canonical Correspondence Analysis suggests that the species distribution is related to the physico-chemical condition of water. Axis two of the ordination diagram displayed the approximately 95.6% of the correlation between species and environmental variables. Dissolved oxygen, conductivity, water temperature and pH showed the highest fluctuations during the sampling period. The species richness (S) showed relationships mainly with water temperature and conductivity. The biodiversity of the gastropods and bivalves from Martín García Island amounts to up to 26 species. Among the Gastropoda, the Planorbidae family made the most sizeable contribution. The Lithogliphidae P. agapetus (26.28%) and P. buschii (9.50%) showed the highest relative frequencies of occurrence within the littoral environments, while the Planorbidae D. cimex (23.83%) and D. kermatoides (11.59%) likewise did so in the inland ponds.

Leptogorgia ignita, a new shallow-water coral species (Octocorallia: Gorgoniidae) from the tropical eastern Pacific

2008 ◽  
Vol 88 (5) ◽  
pp. 893-899 ◽  
Author(s):  
Odalisca Breedy ◽  
Hector M. Guzman
Keyword(s):  
Costa Rica ◽  
Shallow Water ◽  
Coral Community ◽  
Eastern Pacific ◽  
Tropical Eastern Pacific ◽  
Group 13 ◽  
Bright Orange ◽  
Gorgonian Species ◽  
Orange Colour ◽  
Water Coral

Leptogorgia ignita is a new gorgonian species characterized by its conspicuous bright orange colour, irregular branching pattern and combination of sclerite types in the coenenchyme, all of the same orange colour, with abundance of capstans and blunt spindles, and less abundant acute spindles. The species was found in a shallow water coral community, 4–12 m deep in Samara Bay, Pacific Costa Rica. Morphologically, L. ignita belongs to the L. rigida-group comprising eight species for the group; 13 Leptogorgia species are known for Costa Rica, and 23 for the entire eastern Pacific. The new species is described, illustrated and compared to the other valid taxa of the group.

Computational study of some nonlinear shallow water equations

Open Physics ◽  
2013 ◽  
Vol 11 (4) ◽  
Author(s):  
Ali Bhrawy ◽  
Mohamed Abdelkawy
Keyword(s):  
Exact Solutions ◽  
Shallow Water ◽  
Periodic Solutions ◽  
Shallow Water Equations ◽  
Computational Study ◽  
Expansion Method ◽  
Coastal Areas ◽  
Atmospheric Modeling ◽  
Hydraulic Engineering ◽  
Nonlinear Shallow Water Equations

AbstractThe shallow water equations have wide applications in ocean, atmospheric modeling and hydraulic engineering, also they can be used to model flows in rivers and coastal areas. In this article we obtained exact solutions of three equations of shallow water by using $\frac{{G'}} {G} $-expansion method. Hyperbolic and triangular periodic solutions can be obtained from the $\frac{{G'}} {G} $-expansion method.

scholarly journals A NUMERICAL MODEL OF STORM WAVES IN SHALLOW WATER

1980 ◽  
Vol 1 (17) ◽  
pp. 45 ◽  
Author(s):  
A. Hauguel
Keyword(s):  
Numerical Model ◽  
Shallow Water ◽  
Coastal Areas ◽  
Storm Waves ◽  
Analytical Results ◽  
Linear Waves ◽  
Non Linear

For studying storm waves in coastal areas, usual waves theories are no more valid. The presented enoidal theory allows the modelling of these problems. Furthermore, thanks to its non-linear properties, it makes possible the simulation of many phenomena usually neglected. A numerical model using this theory has been developped. it has been tested against analytical results and certain properties of non-linear waves experimentaly observed. Finaly, the practical problems raised by the utilisation of this model for harbour agitation computations, have been solved.

scholarly journals Simulation of ocean waves in coastal areas using the shallow-water equation

2019 ◽  
Vol 1402 ◽  
pp. 077025 ◽  
Author(s):  
D Muliyati ◽  
D Ambarwulan ◽  
W Sinarno ◽  
D Sumardani ◽  
F Bakri ◽  
...  
Keyword(s):  
Shallow Water ◽  
Shallow Water Equation ◽  
Ocean Waves ◽  
Coastal Areas

scholarly journals Modeling Water Quality Parameters Using Landsat Multispectral Images: A Case Study of Erlong Lake, Northeast China

2021 ◽  
Vol 13 (9) ◽  
pp. 1603
Author(s):  
Bazel Al-Shaibah ◽  
Xingpeng Liu ◽  
Jiquan Zhang ◽  
Zhijun Tong ◽  
Mingxi Zhang ◽  
...  
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Shallow Water ◽  
Deep Water ◽  
Northeast China ◽  
Quality Parameters ◽  
Water Quality Parameters ◽  
Multispectral Images ◽  
Landsat Images

Erlong Lake is considered one of the largest lakes in midwest Jilin, China, and one of the drinking water resources in neighboring cities. The present study aims to explore the usage of Landsat TM5, ETM7, and OLI8 images to assess water quality (V-phenol, dissolved oxygen (DO), NH4-N, NO3-N) in Erlong Lake, Jilin province, northeast China. Thirteen multispectral images were used in this study for May, July, August, and September in 2000, 2001, 2002, and October 2020. Radiometric and atmospheric corrections were applied to all images. All in situ water quality parameters were strongly correlated to each other, except DO. The in situ measurements (V-phenol, dissolved oxygen, NH4-N, NO3-N) were statistically correlated with various spectral band combinations (blue, green, red, and NIR) derived from Landsat imagery. Regression analysis reported that there are strong relationships between the estimated and retrieved water quality from the Landsat images. Moreover, in calibrations, the highest value of the coefficient of determination (R2) was ≥0.85 with (RMSE) = 0.038; the lowest value of R2 was >0.30 with RMSE= 0.752. All generated models were validated in different statistical indices; R2 was up to 0.95 for most cases, with RMSE ranging from 1.390 to 0.050. Finally, the empirical algorithms were successfully assessed (V-phenol, dissolved oxygen, NH4-N, NO3-N) in Erlong Lake, using Landsat images with very good accuracy. Both in situ and model retrieved results showed the same trends with non-significant differences. September of 2000, 2001, and 2002 and October of 2020 were selected to assess the spatial distributions of V-phenol, DO, NH4-N, and NO3-N in the lake. V-phenol, NH4-N, and NO3-N were reported low in shallow water but high in deep water, while DO was high in shallow water but low in deep water of the lake. Domestic sewage, agricultural, and urban industrial pollution are the most common sources of pollution in the Erlong Lake.

scholarly journals Distribución espacio-temporal de la temperatura, salinidad y oxígeno disuelto alrededor del Domo Térmico de Costa Rica

2016 ◽  
Vol 64 (1) ◽  
pp. 135
Author(s):  
Omar G. Lizano
Keyword(s):  
Costa Rica ◽  
Dissolved Oxygen ◽  
Water Column ◽  
Tropical Pacific ◽  
Eastern Tropical Pacific ◽  
The North ◽  
Tropical Oceans ◽  
Organic Matter Oxidation ◽  
Minimum Zone ◽  
High Concentrations

<p>The Costa Rica Thermal Dome (CRTD) is an oceanographic phenomenon in the Eastern Tropical Pacific (ETP). This is a region of very high biological productivity, resulting in high concentrations of phytoplankton, sea birds, and large pelagics, such as tunas, dolphins and whales. Few publications have looks at the station variability of the water column of the CRTD. Here, horizontal and vertical distribution of some oceanic parameters was analyzed to show the dynamics of ETP, its influence on the CRTD, climatic variations and relationships that justify their distributions. Climatological monthly mean data of Ocean Data View (ODV) from 1900 to 2009 were used to compile profiles of the water column’s temperature, salinity and dissolved oxygen, and their spatial distributions around the Costa Rica Thermal Dome (CRTD). Monthly variations of these parameters depend on the intensity and extent of ocean-meteorological phenomena in the Eastern Tropical Pacific (ETP), which are related to the north-south migration of Intertropical Convergence Zone (ITCZ). The monthly climatic variation of these variables is analyzed down to 200 m depth. Increased climate variability is found in the water column at stations north and east of the CRTD. The two stations north of the CRTD, closer to the coast, are the ones most affected by the wind in front of the Gulf of Papagayo and where the greatest monthly upwelling variation occurs in this region. The distribution and concentration of dissolved oxygen depends on the ocean-atmospheric dynamics. Oxygen is consumed by respiration and organic matter oxidation around CRTD. Moreover, this is one of the regions of the tropical oceans where an Oxygen Minimum Zone (OMZ) exist, which is related also to poor water circulation or lack ocean ventilation. Sources of dissolved oxygen are linked with sub-surface currents coming from the west and from the south of the geographic equator.</p><div> </div>

scholarly journals Abundancia, tamaño y estructura poblacional del tiburón punta blanca de arrecife, Triaenodon obesus (Carcharhiniformes: Carcharhinidae), en Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica

2017 ◽  
pp. 339-346
Author(s):  
Ilena Zanella ◽  
Andrés López-Garro ◽  
Geiner Golfín-Duarte ◽  
Joel C. Sáenz
Keyword(s):  
Population Structure ◽  
Costa Rica ◽  
Coral Reefs ◽  
Shallow Water ◽  
Relative Abundance ◽  
National Park ◽  
Average Length ◽  
Sphyrna Lewini ◽  
Baseline Information ◽  
Triaenodon Obesus

Abundance, size and population structure of whitetip reef sharks, Triaenodon obesus (Carcharhiniformes: Carcharhinidae), in Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica. Approximately 12 species of shark inhabit at Coco Island National Park (PNIC); some are migratory, such as the hammerhead shark (Sphyrna lewini) and whale shark (Rincodon typus), and others are resident, like the whitetip shark (Triaenodon obesus). The whitetip shark is a species related to coral reefs, it inhabits coastal environments and is nocturnal and, it is very common in tropical waters, but there are few studies worldwide. In fact, only short researches have been done about their behavior at PNIC. Therefore, this study aimed to give data about the abundance, size and population structure of the whitetip shark at Chatham Bay in Coco Island National Park, providing baseline information for monitoring its population which is also very vulnerable to climate change. In order to accomplish this aim, a mark-recapture method was used, as well as underwater visual counts to determine their relative abundance and visual recaptures at Chatham Bay. The most effective hours for tagging were between 18:00 and 22:00 (sunset), when the whitetip sharks were more active probably related to foraging behavior. In addition, the depth was a relevant factor for tagging, sharks were caught in shallow water (10.9±1.9m). This species prefers to feed in shallow water and this behavior is probably related to the distribution and occurrence of rock and coral reefs in Chatham Bay. Based on the results, whitetip shark do not have a defined spatial ontogenic segregation, since in the same sites both juveniles and adults were found. The study confirmed that whitetip shark use specific residence sites: during the tagging trips, different individuals were recaptured; and during the underwater counts, at least 32.76% of tagged sharks were observed. The average length of the tagged sharks was 101.8±12.1cm (130.0cm maximum and 71.0cm minimum). The relative abundance of the whitetip shark in Chatham Bay observed was estimated on 49.5±10.4 sharks/hour. Furthermore, using the recapture data obtained during the night tagging expeditions, a population of 408 (IC = 181-1050) sharks was estimated. Citation: Zanella, I., A. López-Garro, G. Golfín-Duarte & J.C. Sáenz. 2012. Biología del tiburón punta blanca de arrecife, Triaenodon obesus (Carcharhiniformes: Carcharhinidae), en Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica. Rev. Biol. Trop. 60 (Suppl. 3): 339-346. Epub 2012 Dec 01.

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