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1.
Rev. biol. trop ; 69(supl. 1)mar. 2021.
Article in English | LILACS-Express | LILACS | ID: biblio-1507751

ABSTRACT

Introduction: The family Benthopectinidae is composed of deep-sea sea stars distributed in eight genera and approximately 70 valid species. So far, only five species of this family have been reported for the Mexican waters of the Gulf of Mexico. Objective: To provide an updated local taxonomy of this family. Methods: A total of 566 specimens deposited in the Echinoderm National Collection, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, and the National Museum of Natural History, Smithsonian Institution, collected from 1952 to 2015, were taxonomically examined. Results: We present descriptions, photographs, and an illustrated dichotomous key for Benthopecten simplex simplex, Cheiraster (Barbadosaster) echinulatus, Cheiraster (Cheiraster) planus, Cheiraster (Christopheraster) blakei, and Cheiraster (Christopheraster) mirabilis in the region. Conclusions: The five studied species represent 6 % of the world biodiversity of the family and can now be identified with the illustrated key.


Introducción: La familia Benthopectinidae está compuesta por estrellas de mar de profundidad distribuidas en ocho géneros y 70 especies válidas aproximadamente. Hasta el momento, se han reportado cinco especies de esta familia para las aguas mexicanas del Golfo de México. Objetivo: Realizar una actualización local de la taxonomía de esta familia. Métodos: Se examinaron un total de 566 especímenes depositados en la Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México y el Museo Nacional de Historia Natural, Smithsonian Institution, recolectados de 1952 a 2015. Resultados: Presentamos descripciones, fotografías y una clave dicotómica ilustrada para Benthopecten simplex simplex, Cheiraster (Barbadosaster) echinulatus, Cheiraster (Cheiraster) planus, Cheiraster (Christopheraster) blakei, y Cheiraster (Christopheraster) mirabilis en la región. Conclusiones: Las cinco especies estudiadas representan el 6 % de la diversidad mundial de la familia y ahora pueden ser identificadas con la clave ilustrada proporcionada.

2.
Rev. biol. trop ; 61(4): 1967-1979, oct.-dic. 2013. ilus, mapas, tab
Article in English | LILACS | ID: lil-703941

ABSTRACT

The Hannibal Bank sits within the Coiba UNESCO World Heritage Site in Pacific Panama and is also a fisheries management zone. Despite the protected status of the area and the importance of the Bank for commercial fish species such as snapper and tuna, the seamount has received no detailed survey except some collection of organisms. This study mapped the major topographic features and complexity of the Hannibal Bank seamount using acoustic remote sensing. A survey area of around 125km² was defined using existing charts and side-scan sonar data were collected during July 2008. A bathymetric output was imported to ArcGIS where a digital bathymetric model and slope map were created. The Benthic Terrain Modeler BTM extension for ArcGIS was used to calculate bathymetric position index and rugosity, and used to create a map of zones representing the various seabed morphology zones. The Hannibal bank is an elongated, triangular guyot flat topped seamount, which ranges in depth from 53m to 416m, covers an area of 76km² and is 14.4km long and 7.1km wide. Hannibal bank is composed of steep slopes, more gentle slopes, top of the seamount, crests elevated ridges at the top of the pinnacles, rugose areas on crests, top of seamount and slope, gullies and pinnacles. The bank is asymmetric in nature with the Northerly side having a relatively gentle slope with gullies across the surface compared to the SouthWest side which is far steeper and more rugose. There are two pinnacles to the North and South East of the bank that range in depth from 180 to 333m. Rocky substrate makes up 22.6km² of the bank and sediment 37.8km². The bank and its steeply sided, rugose areas and pinnacles provide upright structures which can disrupt and topographically enhance currents, increasing productivity. The rugose areas of Hannibal Bank should be primary targets for further research efforts as they may contain corals and their rugosity indicates that these should be some of the highest faunal diversity areas of the bank. Hannibal Bank is likely to come increasing pressure in the future through climate change and fishing and this study has produced valuable information to assist in the future mapping and management of habitats, associated species and fisheries.


El Banco Hannibal se encuentra en Coiba que es Patrimonio de la Humanidad de UNESCO en el Pacífico de Panamá y es una importante zona de pesca. Este estudio evaluó las principales características topográficas y la complejidad de la montaña submarina Banco Hannibal mediante el uso de sensores remotos acústicos. A pesar del estado de protección de la zona y la importancia para las especies comerciales de peces como el pargo y el atún, la montaña submarina no ha tenido ningún estudio detallado salvo alguna colección de organismos. El área de estudio de alrededor de 125km² identificada usando cartas de navegación fue definida usando datos de sonar de barrido lateral durante julio 2008. La información batimétrica fue importada a ArcGIS donde se creó un modelo digital batimétrico DBM y mapa de pendientes. La extensión del ArcGIS Benthic Terrain Modeler BTM se utilizó para calcular el índice de posición batimétrica o BPI pendiente de cada celda relativa a las celdas vecinas y rugosidad. El banco Hannibal es un guyot alargado, triangular montaña submarina plana en parte superior, que se extiende en profundidad desde 53m hasta 416m, tiene una superficie de 76km² y es de 14.4km de largo y 7.1km de ancho. El Banco Hannibal está compuesto por pendientes pronunciadas, pendientes más suaves, parte superior de la montaña submarina, crestas altos relieves en la parte superior, zonas rugosas en las crestas, parte superior de los montes submarinos y pendiente, barrancos y crestas. El banco es asimétrico, con una pendiente relativamente suave y con surcos a través de la superficie en el lado norte en comparación con el lado suroeste que es mucho más pronunciado y más rugoso. Hay dos cumbres al norte y al sureste de la orilla, que varían en profundidad de 180 a 333m. El sustrato rocoso comprende unos 22.6km² del banco y sedimentos 37.8km². El banco y sus caras abruptas, áreas rugosas y pináculos proporcionan estructuras verticales que pueden alterar y mejorar topográficamente las corrientes. Esto se cree produce un afloramiento local que explicaría las mayores agregaciones de peces que son el objetivo de la pesca comercial y deportiva. Es probable que el Banco Hannibal tenga una presión cada vez mayor en el futuro debido al cambio climático y la pesca y este estudio ha producido información valiosa que permite la clasificación de los hábitats para el manejo de las especies asociadas y su pesca, así como la iniciación de la investigación sobre montañas submarinas de Panamá.


Subject(s)
Animals , Conservation of Natural Resources , Fisheries , Geographic Information Systems , Geography , Pacific Ocean , Panama
3.
Biota neotrop. (Online, Ed. port.) ; 13(2): 227-235, Apr-Jun/2013. tab, graf
Article in English | LILACS | ID: lil-682372

ABSTRACT

This review aims to present an updated checklist of scaphopods, based mainly on literature database. There is a total of 40 species (six families) for Brazil, including information about the distribution and bathymetric range of each taxon. We propose two synonyms with the aid of morphometry of the shell, for the genus Gadila: G. longa as junior synonym of G. elongata and G. robusta as junior synonym of G. pandionis.


Uma lista atualizada dos escafópodes da costa brasileira pertencentes a seis famílias é apresentada baseada principalmente em dados da literatura. Há um total de 40 espécies para o Brasil, incluindo informações sobre a distribuição e a faixa batimétrica de cada táxon. Nós propomos dois sinônimos com o auxílio da morfometria da concha, para o gênero Gadila: G. longa como sinônimo júnior de G. elongata e G. robusta como sinônimo júnior de G. pandionis.

4.
Rev. biol. trop ; 60(supl.3): 43-51, nov. 2012. ilus, mapas, tab
Article in Spanish | LILACS, SaludCR | ID: lil-672082

ABSTRACT

The UNESCO GEBCO-08 bathymetric data was used to study the marine provinces around Isla del Coco. Seamounts with depths of less than 1000m from the sea surface were analyzed. Seamounts southward, south- eastward and westward of the island, were identified at depths of 300m from the sea surface, and with heights up to 2700m from the marine bottom. The ecological interconnection of these mountains with Isla del Coco has to be effective, as it could also be within the biological corridor of Eastern Tropical Pacific. A better resolution study around Isla del Coco was done to identify details of the insular platform. A seamount to 14.8km northeast of the island was found, with measured depths of 30-40m, and so far, not reported. This feature explains the presence of fishermen around this site, which is known by them as a place with high productivity. Although more studies are needed, the limits and environmental policies should be modified so as to adequately protect these seamounts, which probably have an important ecological connection with Isla del Coco. Citation: Lizano, O.G. 2012. Rasgos morfológicos alrededor de la Isla del Coco y de sus montes submarinos vecinos, Pacífico de Costa Rica.


Se utilizaron los datos batimétricos GEBCO-08 de la UNESCO para estudiar las provincias marinas alrededor de la Isla del Coco. Se analizaron las montañas submarinas que tuvieran menos de 1000m de profundidad en esta cordillera. Montes submarinos localizados al sur, sureste y oeste de la isla, fueron identificados con profundidades de 300m desde la superficie del mar, y con alturas de hasta 2700m desde el fondo marino. La interconexión ecológica con la Isla del Coco de estos montes debe ser efectiva, como lo serán también dentro del corredor biológico del Pacifico Tropical Este. Se realizó un estudio particular de mayor resolución alrededor de la Isla del Coco para identificar los alcances de la plataforma de la isla. Se encontró un monte submarino a 14.8km al noreste de la isla, con profundidades medidas de 30-40m, que no había sido reportado. Con este rasgo submarino se explica la presencia de pescadores alrededor del este sitio, un sitio conocido en el ambiente de los pescadores, pero que aún no se había asociado a algún fenómeno oceánico en particular. Aunque más estudio es necesario, de comprobarse la conectividad biológica entre los montes submarinos y la Isla del Coco, los límites y las políticas ambientales deberán ser modificados, de manera que se proteja adecuadamente este sistema ecológico.


Subject(s)
Map , Geomorphology , Geographic Mapping , Costa Rica
5.
Acta sci., Biol. sci ; 33(3): 281-287, July-Sept. 2011. ilus, tab
Article in English | LILACS | ID: biblio-874993

ABSTRACT

O presente estudo avaliou a precisão de dois protocolos usados para a confecção de uma carta batimétrica para a Lagoa Central (Lagoa Santa, Estado de Minas Gerais, Brasil). Numa segunda etapa, o estudo estimou todos os parâmetros morfométricos primários e secundários desse ambiente. Finalmente, o estudo avaliou a importância dessas informações na qualidade de água e na ecologia geral do sistema. Os protocolos foram baseados no uso de dois sistemas distintos, usados para o levantamento batimétrico: uma ecossonda Biosonics DT-X (Biosoncs Inc.) e um Ecobatímetro SonarLite (Ohmnex Ltda), ambos acoplados a um D-GPS (Differential Global Positioning System) para a obtenção das coordenadas geográficas de cada profundidade medida. A Lagoa Central de Lagoa Santa é um pequeno lago natural, raso (Zmax < 7,5 m), com profundidade relativa baixa (Zr = 0,5%) e formato côncavo. Essas características a tornam menos propensa à formação de estratificação térmica estável e, portanto, menos sensível à formação de gradientes químicos verticais na coluna de água. Essa configuração pode ser vista como um dos fatores principais que impedem o agravamento do processo de eutrofização verificado nesse sistema.


The goal of this study was to verify the utility and accuracy of two tools to obtain a bathymetric chart for Lagoa Central (Lagoa Santa, State of Minas Gerais, Brazil) and also to assess the morphometric parameters of the lake and their implications in the ecology of this system. The tested tools were the Biosonics DT-X (Biosonics Inc.) echosounder and the SonarLite (Ohmnex Ltda) bathymeter, both coupled to a Differential Global Positioning System (DGPS) to obtain the geographic coordinates associated with the depth in each point. Lagoa Central is a small, shallow (Z max < 7.5 m), with low relative depth values (Zr = 0.5%) and concave. This makes the water body less prone to thermal stratification and more susceptible to eutrophication. Both investigated equipments demonstrated to be suitable for the survey, user-friendly, low-cost and with sub-metric accuracy.


Subject(s)
Water Quality , Biosensing Techniques , Systems Biology , Ecology
6.
Acta biol. colomb ; 15(3): 131-144, dic. 2010.
Article in Spanish | LILACS | ID: lil-635035

ABSTRACT

En el lago Guatavita se estudiaron sus características morfométricas con el objeto de analizar las implicaciones de la morfología sobre su funcionamiento y discutir algunas hipótesis que existen sobre el origen del lago. El lago presenta una cubeta con una forma cónica, bajo desarrollo del perímetro, profundidad máxima de 30 m y profundidad relativa de 7,9%. La curva hipsográfica indica que el lago presenta un aumento constante del área de la sección con respecto a la profundidad. La forma del lago promueve una estratificación térmica que se mantiene durante ocho meses del año, un hipolimnio hipóxico y un fuerte gradiente en la conductividad y en la concentración de amonio. Estos resultados indican un papel muy importante de la profundidad sobre las características físicas y químicas del lago que a su vez determinan la dinámica de las comunidades biológicas y una baja productividad fitoplanctónica.


Morphometric characteristics of the Lake Guatavita were investigated in order to disclose possible connections with its ecological functioning and discuss some hypotheses that exist about the origin of this lake. The lake has a basin with a conical shape, low perimeter development, maximum depth of 30 m and relative depth of 7.9%. The hypsographic curve reveals a constant increase of the sectional area with depth. The lake shape promotes a permanent thermal stratification during eight months of the year with a hypoxic hypolimnion and a strong vertical gradient in the conductivity and ammonium concentration. These results indicate an important role of depth on the physical and chemical lake characteristics which in turn explain the dynamics of biological communities and are responsible for a relatively low phytoplankton primary productivity.

7.
Acta sci., Biol. sci ; 32(1): 49-54, jan.-mar.2010. ilus, map, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1460631

ABSTRACT

Carioca Lake is located within the limits of the Rio Doce State Park, in the eastern part of the state of Minas Gerais. This park, one of the largest natural reserves of the Atlantic Rain Forest in Brazil, is a hotspot of tropical biodiversity. The purpose of this study was to update existing information on the bathymetry and morphometric features of the lake, using differential GPS (DGPS) technology for data collection, coupled to a digital echo sounder. The bathymetry was based on the acquisition of 1106 points, where the depths as well as the geographic coordinates were obtained. The new study allowed the refinement of existing primary and secondary morphometric data for this lake.


A lagoa Carioca está localizada nos limites do Parque Estadual do Rio Doce (PERD), na região leste do Estado de Minas Gerais. Este parque, uma das maiores reservas naturais da Mata Atlântica no Brasil, é um hotspot da biodiversidade. Este trabalho tem por objetivo elaborar um novo mapeamento batimétrico e descrever as características morfométricas deste ambiente utilizando a tecnologia do GPS diferencial (DGPS) para coleta dos dados de localização geográfica em conjunto com uma ecossonda digital, equipamento para coleta das informações de profundidade. O levantamento batimétrico da lagoa Carioca foi baseado num total de 1106 pontos com profundidade e localização conhecidas, obtidas com precisão submétrica. O novo estudo permitiu o refinamento dos dados morfométricos primários e secundários existentes para este lago.


Subject(s)
Biodiversity , Brazil
8.
Ciênc. rural ; 39(9): 2482-2487, dez. 2009. tab, ilus
Article in Portuguese | LILACS | ID: lil-534742

ABSTRACT

No Estado do Rio Grande do Sul, a utilização crescente de sistemas de irrigação vem tornando cada vez mais importante a reservação de água através de barragens. Neste caso, é essencial a determinação do volume de água disponível nessas estruturas para o adequado planejamento dos sistemas irrigados e outorga para o uso da água. Atualmente, a determinação do volume é pouco frequente porque o método direto (batimetria) caracteriza-se por ser oneroso, além de exigir mão-de-obra especializada e tempo disponível. Diante do exposto, este trabalho teve por objetivo avaliar um modelo matemático para a determinação do volume de água armazenado em reservatórios de irrigação. O modelo matemático escolhido foi representado pela fórmula de Schoklisch, em que o volume de água de um reservatório é dado pelo produto da área e profundidade máxima em nível normal e o parâmetro de Schoklisch (η). Foi feita a análise do parâmetro η a partir dos dados fornecidos por 210 reservatórios com finalidade de irrigação, localizados na região da Campanha do Estado do Rio Grande do Sul. Através dos resultados, pode-se observar que o valor do coeficiente de Schoklisch (η) variou entre 0,47 e 0,53, apresentando um valor médio de 0,50 e desvio padrão de 0,05, considerando-se os municípios em conjunto. Observou-se, ainda, que todos os locais estudados enquadraram-se na classe de desempenho ótimo. Os coeficientes de determinação encontrados para as regiões de estudo foram superiores a 0,99. A relação entre o volume estimado e o volume observado em reservatórios demonstra o alto grau de correlação entre os valores testados e permite a recomendação do uso do modelo de Schoklisch para a determinação do volume de água armazenado em reservatórios de irrigação nas localidades em estudo.


In the Rio Grande do Sul state, the irrigation systems for growing use contributes to make the water reserves through barrages more important. In this case, it is essential to determine the volume of water available in these structures for the appropriate projection of the irrigated systems and concessions for water usage.Currently, the determination of the volume is not much frequent because the direct method (bathymetry) is characterizes as onerous and besides demands specialized workforce and available time. Thus, this research had the objective to evaluate a mathematical model to determine the volume of water stored in irrigation reservoirs The mathematical model chose was represented by Schoklisch formula, where the volume of water of a reservoir is given by the product of the area and the maximum depth in normal level and the Schoklisch parameter (η). The analysis of the parameter η was based on the data provided by 210 reservoirs destined to irrigation, located in the Campanha of Rio Grande do Sul state. Through the results it is possible to notice that the Schoklisch (η) coefficient value varied between 0.47 and 0.53, presenting a average value of 0.50 and standard deviation of 0.05 considering the localities altogether. It was also observed, that all localities studied fitted in the class of optimum performance. The coefficients of determination found for the studied regions were superior to 0.99. The relation between the expected volume and the observed volume in reservoirs demonstrates the high degree of correlation between the tested values and allows the recommendation of the Schoklisch model for the determination of the volume of water stored in irrigation reservoirs in the localities studied.

9.
Rev. biol. trop ; 57(supl.1): 19-29, nov. 2009. graf, mapas, tab
Article in Spanish | LILACS, SaludCR | ID: lil-637922

ABSTRACT

Batimetry, salinity, temperature, and dissolved oxigen water of the Marino Ballena National Park, Pacific, Costa Rica. Between September 2003 and April 2005, the bathymetry and the behavior of the temperature, salinity, dissolved oxygen and oxygen percent saturation were studied at Marino Ballena National Park (MBNP). The park has an average depth of 14.9±9.1m, and maximal depth of 37.3 m. The internal section of the bay is shallow, not reaching more than 20m, while the external section posses a more pronounced slope, reaching easily 37 m. Mean values of superficial salinity were: 29.1±4.3‰, temperature 29.7±1.3ºC, dissolved oxygen 6.7±1.3 mg/l, and oxygen percent saturation 115.6±22.1%. Significant differences were only detected between the internal and external stations for salinity and temperature according to depth, during the rainy season. The lower values of salinity and temperature were observed on the rainy season, and the highest on the dry season, with a continuous of dissolved oxygen and saturation. The similarity between the stations and the fact that significant differences were only for salinity and temperature according to depth, suggests that the waters of the park behave in similar manner over time and that the area is very dynamic and homogenous, with currents strong enough to mix the water column on the park. The park is located in a very productive area, resulting in a high value of oxygen percent saturation (120%). This suggests that there are good conditions for the development of phytoplankton, zooplankton and other groups. Rev. Biol. Trop. 57 (Suppl. 1): 19-29. Epub 2009 November 30.


Se realizó un estudio sobre la batimetría del PNMB y del comportamiento de la temperatura, salinidad, oxígeno disuelto y porcentaje de saturación de oxígeno entre setiembre 2003 y abril 2005. El parque posee una profundidad promedio de 14.97± 9.11m y una profundidad máxima detectada de 37.33m. La sección interna de la bahía es poco profunda, no alcanzando más de 20m de profundidad, mientras que en la parte externa la pendiente es más pronunciada, alcanzando rápidamente los 37 m. A lo largo del estudio, los valores promedio superficiales de salinidad fueron de 29.1±4.3‰, de temperatura 29.7±1.3ºC, de concentración de oxígeno disuelto 6.7±1.3mg/l, y del porcentaje de saturación de oxígeno 115.6±22.1%. Entre las estaciones interna y externa solo se observaron diferencias significativas en cuanto a la salinidad y la temperatura por profundidad, como producto de la época lluviosa. Los valores más bajos de salinidad y temperatura se observaron para la época lluviosa y los más altos en la época seca, mientras que los valores de oxígeno disuelto y porcentaje de saturación de oxígeno presentaron un incremento continuo a través del tiempo. La similitud entre las estaciones y el hecho de haber encontrado diferencias significativas solamente entre la salinidad y la temperatura en cuanto a la profundidad, hacen pensar que a lo largo del tiempo las aguas del parque se comportan de manera muy similar y que es una zona muy dinámica y homogénea con corrientes lo suficientemente fuertes para mezclar la columna de agua del parque. El PNMB es una zona muy productiva debido a los altos valores de saturación de oxígeno observados a lo largo del tiempo (120%). Esto hace pensar que existen condiciones apropiadas para el desarrollo del fitoplancton, zooplancton y otros grupos tróficos.


Subject(s)
Mass Spectrometry , Marine Fauna , Marine Flora , Dissolved Oxygen , Salinity , Temperature , Costa Rica
10.
Rev. biol. trop ; 49(Supl.2): 163-170, dic. 2001. graf, tab, mapas
Article in Spanish | LILACS | ID: lil-502398

ABSTRACT

The bathymetry of Coco's Island (UNESCO Natural and Cultural World Patrimony), located approximately 500 km from the Pacific coast of Costa Rica, is not well known. It has a high marine biodiversity and also represents a meeting site for many species traveling throughout the Pacific Ocean. The insular shelf is irregular in extension and also in bathymetric features. The northeast limit is defined by the 109.8-128.1 m contours (60-70 fathoms) while the 183 m contour (100 fathoms) practically defines the rest of the island, from which the depth gradient is steep. The maximum extension is to the northeast with a longitude of 13 km. In this context the present limits of the marine park (5 km), are insufficient to protect the whole insular shelf. Current regulation should be modified to prevent fishing activities less than 15 km from the Island.


Subject(s)
Animals , Biodiversity , Conservation of Natural Resources , Costa Rica , Geography , Pacific Islands
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