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Variabilidad temporal de los ensamblajes de macroalgas en arrecifes rocosos de Bahía de Loreto

ALEJANDRA MAZARIEGOS VILLARREAL (2012)

"Las variaciones interanuales en la composición de especies de macroalgas y sus atributos (división, morfología, estrato y afinidad biogeográfica), así como la correlación de la riqueza por atributo con la temperatura y concentración de clorofila a se analizaron a partir de datos obtenidos en 15 muestreos estacionales durante cuatro años consecutivos (2005 a 2008) en seis sitios ubicados en Bahía de Loreto (n = 90). La variabilidad temporal de los atributos de las especies en los ensamblajes fue probada por medio de pruebas de independencia de χ2 y la variabilidad en la composición de especies se analizó por medio de análisis de similitud y dendrogramas de agrupamiento. Se identificaron 169 especies de macroalgas. La mayoría de las especies pertenecieron a la división Rhodophyta, tuvieron morfología filamentosa, fueron formadoras de tapetes y con afinidad templada. La frecuencia de las especies de macroalgas por atributo no presentó dependencia con los años, indicando que la estructura de los ensamblajes se mantiene a pesar de la baja similitud en la composición de especies. La riqueza de macroalgas (de 29 ± 7 especies en octubre a 40 ± 7 especies en julio), temperatura (de 19.6 ± 0.8 °C, en invierno a 29.8 ± 0.6 °C en verano) y concentración de clorofila a (de 1.6 ± 0.3 mg m-3 en invierno a 0.4 ± 0.2 mg m-3 en otoño) presentaron variaciones estacionales recurrentes entre los años. Las correlaciones entre la riqueza de especies y la temperatura y concentración de clorofila a fueron significativas mostrando que los factores ambientales tienen un papel importante en la estructura de los ensamblajes de macroalgas en esta región."

"We analyzed interannual variations in macroalgal species composition, their attributes (division, morphology, layering and biogeographic affinities), and the correlation of species richness by attribute with temperature and chlorophyll a concentrations from 15 seasonal samplings in six sites located in Bahía de Loreto (n = 90) during four consecutive years (2005 to 2008). Temporal variability in their attributes was tested by means of χ2 independency test and species composition variability was analyzed by means of similarity and cluster analysis. A total of 169 macroalgal species were identified, most of them belonged to the Rhodophyte division; they were filamentous, turf formers, and had temperate affinities. The species attribute frequency was independent of the year, which indicates that the assemblage structure is maintained despite the low similarity in species composition. Macroalgal species richness (from 29 ± 7 species in January to 40 ± 7 species in July), temperature (from 19.6 ± 0.8 ºC in winter to 29.8 ± 0.6 ºC in summer), and the chlorophyll a concentrations (from 1.6 ± 0.3 mg m-3 in winter to 0.4 ± 0.2 mg m-3 in fall) showed recurrent seasonal variations between years. The positive correlation between species richness and temperature and chlorophyll a concentration reinforced the idea that abiotic factors play a primary role in structuring the macroalgal assemblages in this region."

Book part

variación interanual, macroalgas, Bahía de Loreto, Golfo de California interannual variation, macroalgae, Bahía de Loreto, Gulf of California BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ALGOLOGÍA (FICOLOGÍA) ALGOLOGÍA (FICOLOGÍA)

Variabilidad espaciotemporal de la temperatura superficial del mar en el Golfo de California

Time and spatial variability of sea surface temperature in the Gulf of California

Luis Soto (1999)

"Catorce años de imágenes infrarroja de satélite (1983–1996) son usadas para examinar la variabilidad de la temperatura superficial del mar (TSM) del Golfo de California. El estudio de la TSM se enfocó a las escalas semianual, anual e interanual y al promedio. En promedio, la TSM disminuye de la boca hacia la cabeza y su variabilidad aumenta. La escala anual es la responsable de la mayor parte de la variabilidad de la TSM, la cual oscila en fase con pequeñas variaciones de norte a sur. Espacialmente se encuentra en la región norte la formación de núcleos cálidos en invierno, asociados con giros anticiclónicos y núcleos fríos en verano, asociados con giros ciclónicos. La transición de primavera muestra un giro ciclónico ubicado más sobre el lado continental y la de otoño muestra un giro anticiclónico no muy bien definido. La TSM en la región de las islas es siempre menor que el resto del golfo. La variabilidad transversal de la estructura de TSM en la región central y sur se asocia con surgencias. La estructura espacial de la amplitud semianual es tal que aumenta hacia la cabeza al igual que la escala anual. La amplitud en la cabeza es el doble que en la boca y presenta gradientes menores. En la escala interanual, los eventos de 1988–1989 y 1992–1993 se distinguen por llegar hasta la región norte. En ambos eventos, las anomalías aparecen simultáneamente en la región de la boca e islas y a medida que evolucionan se intensifican más en la región de las islas. Este comportamiento no había sido descrito anteriormente. Los eventos de 1985, 1987 y 1990 presentan una evolución “normal”, es decir, una invasión progresiva de aguas cálidas de la región sur hacia dentro del golfo."

"Fourteen years of satellite images (1983–1996) are used to examine the variability of sea surface temperature (SST) in the Gulf of California. The study focussed on the semiannual, annual and interannual scales and on the average. On average, SST decreases from the mouth to the head and its variability increases. The annual scale is responsible for most of the temporal variability, which oscillates in phase with minor north-south variations. The northern gulf shows the formation of warm anticycloniceddies during winter and cold cyclonic eddies during summer. The spring transition shows a cyclonic eddy closer to the mainland side of the gulf; the autumn transition shows a not well-defined anticyclonic eddy. The SST around the island region is always colder than the rest of the gulf. The lateral variability in the central and southern regions is associated with upwelling phenomena. The semiannual and annual amplitudes increase to the north by a factor of two with respect to the southern region. On the interannual scale, the 1988–1989 and 1992–1993 events reach all the gulf. Both events appear first in the south and island regions, and the signals are more intense at the islands than the rest of the gulf. This behavior has not been reported before. The 1985, 1987 and 1990 events show a “normal” evolution, i.e., the warm waters appear in the south and gradually progress into the gulf."

Article

Temperatura superficial, Variabilidad estacional e interanual, Golfo de California, Sea surface temperature, Seasonal and interannual variability, Gulf of California CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA FÍSICA (VE R 5603 .04)

Variabilidad del estado trófico y la biomasa del fitoplancton de Bahía Concepción, Golfo de California (1997-1999)

Variability of the trophic state and phytoplankton biomass of Bahia Concepcion, Gulf of California (1997-1999)

DAVID JAVIER LOPEZ CORTES Ismael Gárate-Lizárraga JOSE JESUS BUSTILLOS GUZMAN ROSALBA ALONSO RODRIGUEZ IBAN MURILLO MURILLO (2003)

"Con el propósito de determinar la variación de la biomasa del fitoplancton (clorofila a) y el estado trófico de Bahía

Concepción ubicada en la parte central oeste del Golfo de California, se realizó un estudio hidro-biológico durante

el período de 1997 a 1999. Se determinó la temperatura, la concentración del oxígeno disuelto y de nutrientes

inorgánicos (nitrato, nitrito, fosfato y silicato), y la biomasa fitoplanctónica (clorofila a). Las condiciones

hidrográficas muestran un período de mezcla (octubre-abril), dos de transición (abril-mayo, septiembre-octubre)

y uno de estratificación (junio-septiembre). Las temperaturas más cálidas durante el periodo de estudio fueron

observadas durante 1998 y las más frías en 1997 para todos los períodos hidrográficos. Los valores de oxígeno

disuelto muestran una zona de hipoxia durante el período estratificado (< 2.7±0.78 ml l-1), por abajo de los 20

metros de profundidad. Durante los períodos de transición se observó un incremento de la biomasa

fitoplanctónica similar al que se observa como máximos de primavera y verano de algunas lagunas costeras en

latitudes similares, sin embargo la mayor biomasa se detectó en el período de estratificación, particularmente por

abajo de los 15 m. La escala de nutrientes mostró un estado de eutrofía para fosfato y silicato todo el año. El índice

trófico reveló que la oligotrofía para fosfatos, nitratos y nitritos es el estado dominante, con excepción de los

períodos de transición, que es cuando la mesotrofía se presentó. Los resultados sugieren que los incrementos

fitoplanctónicos en Bahía Concepción se deben al suministro de nutrientes de origen natural y que las condiciones

tróficas (mesotrofía o eutrofía), son determinadas por las condiciones hidrográficas del área."

"To determine the effect of the phytoplankton biomass and the trophic status in Bahía Concepción in the centralwest

part of the Gulf of California an hydro-biologic study was conducted from 1997 to 1999. Temperature,

dissolved oxygen, inorganic nutrients (nitrate, nitrite, phosphate and silicate) and phytoplankton biomass

(chlorophyll a) concentrations were measured. Hydrographic conditions shown a mixing period (October-April),

two transition periods (April-May and September-October) and a stratification period (June-September).

Warmest temperatures were observed during 1998 and coldest in 1997. Dissolved oxygen values shown an

hypoxic layer (<2.7±0.78 ml l-1), during the stratified period below 20 m depth. During the transition period two peaks of phytoplankton biomass were observed, on spring and summer, which matched with those reported for

coastal lagoons at similar latitudes, however the highest biomasses were observed in the stratification period,

particularly below 15 m depth. The scale of nutrients showed an eutrophy for phosphate and silicate all the year.

The trophic index revealed an oligotrophy state for phosphate, nitrate and nitrite had a dominant status with the

exception for the transition periods, when the mesotrophic conditions were presents. These results suggest

that phytoplankton biomass is associated with the natural inputs of nutrients and that trophic conditions

(mesotrophy or eutrophy) were determined for the hydrographic of the area. "

Article

Biomasa de fitoplancton, estado trófico, Bahía Concepción, Golfo de California. Phytoplankton biomass, trophic status, Bahía Concepción, Gulf of California. BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL

Dust Deposition on the Gulf of California Caused by Santa Ana Winds

CHRISTIAN ADRIAN ALVAREZ BAEZ JOSE NOEL CARBAJAL PEREZ Luis Felipe Pineda Martínez JOSE TUXPAN VARGAS David Enrique Flores Jiménez (2020)

"Numerical simulations revealed a profound interaction between the severe dust storm of 2007 caused by Santa Ana winds and the Gulf of California. The weather research and forecasting model coupled with a chemistry module (WRF-CHEM) and the hybrid single-particle Lagrangian integrated trajectory model (HYSPLIT) allowed for the estimation of the meteorological and dynamic aspects of the event and the dust deposition on the surface waters of the Gulf of California caused by the erosion and entrainment of dust particles from the surrounding desert regions. The dust emission rates from three chosen areas (Altar desert, Sonora coast, and a region between these two zones) and their contribution to dust deposition over the Gulf of California were analyzed. The Altar Desert had the highest dust emission rates and the highest contribution to dust deposition over the Gulf of California, i.e., it has the most critical influence with 96,879 tons of emission and 43,539 tons of dust deposition in the gulf. An increase of chlorophyll-a concentrations is observed coinciding with areas of high dust deposition in the northern and western coast of the gulf. This kind of event could have a significant positive influence over the mineralization and productivity processes in the Gulf of California, despite the soil loss in the eroded regions."

Article

Numerical simulation Santa Ana winds Dust storm WRF-CHEM Gulf of California Dust deposition CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO CIENCIAS DE LA ATMÓSFERA CIENCIAS DE LA ATMÓSFERA

VARIABILITY OF SARDINE CATCH AS RELATED TO ENRICHMENT, CONCENTRATION, AND RETENTION PROCESSES IN THE CENTRAL GULF OF CALIFORNIA

Daniel Bernardo Lluch Cota SALVADOR EMILIO LLUCH COTA DANIEL LLUCH BELDA Manuel Otilio Nevárez Martínez ALEJANDRO FRANCISCO PARES SIERRA SERGIO HERNANDEZ VAZQUEZ (1999)

"The sardine (Sardinops sugax) fishery of the Gulf of California is among Mexico’s most important fisheries, accounting for the largest catch and providing many productive jobs. During the early 1990s, this fishery collapsed to less than 3% of the production maximum. Surprisingly, after two years of very low catch the fishery recovered quickly. We propose that these large fluctuations may be explained mainly by physical processes (enrichment, retention, and concentration) governing the sardine spawning habitat. The spawning area may be influenced by processes such as tidal mixing, Winter northwesterly winds, coastal upwelling, prevailing Surface currents, and Ekman transport, but most of its variability is believed to be wind-forced. Therefore we attempted to relate spawning extension to wind variations. By fitting an equation that expresses spawning as a probability function of a wind-derived index, we have built a spawning-probability time series based on egg and larval survey data and then tested against an independent series of landings and biomass indices (number of recruits and adults). Results show coherent relations between the spawning-probability series and the biological and fisheries data, despite large fluctuations (collapse and recovery). Our results are encouraging and may provide a solid theoretical basis for future environment- monitoring systems for the sardine fishery in the gulf."

Article

SARDINE, GULF OF CALIFORNIA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE TÉCNICAS PESQUERAS TÉCNICAS PESQUERAS

Co-ocurrencia de Chattonella marina y Gymnodinium catenatum en laBahía de LaPaz, Golfo de California (primavera2009)

Co-ocurrence of Chattonella marina and Gymnodinium catenatum inBahía de LaPaz, Gulf of California (Spring2009)

DAVID JAVIER LOPEZ CORTES CHRISTINE JOHANNA BAND SCHMIDT Ismael Gárate-Lizárraga JOSE JESUS BUSTILLOS GUZMAN FRANCISCO EDUARDO HERNANDEZ SANDOVAL ERICK JULIAN NUÑEZ VAZQUEZ (2011)

"Durante el período del 24 de marzo al 14 de mayo de 2009 en la Bahía de La Paz, se obtuvieron muestras de agua y de red para análisis de fitoplancton. Una alícuota se fijó con una solución de Lugol para la identificación y cuantificación, la de red se utilizó para la identificación in vivo. Semanalmente se midió la temperatura in situ, se determinaron nutrientes inorgánicos y clorofila a en tres estaciones. Se identificaron dos especies: Chattonella marina (Subrahmanyan) Y. Hara et Chihara y Gymnodinium catenatum Graham. Chattonella marina fue la especie más abundante con densidades de 14 × 103 a 36 × 103 cél. L-1 a nivel sub-superficial. Gymnodinium catenatum se registró con densidades de 1 × 103 a 19 × 103 cél. L-1 . La temperatura del agua fue homogénea desde la superficie hasta los 20 m de profundidad, con un intervalo de 19.5 a 22.0 °C y de 20.0 a 21.5 °C a finales de marzo y abril respectivamente. En la primera mitad de mayo se inició la estratificación, con una diferencia térmica de 5.0 °C entre la superficie y los 20 m. Los nitratos variaron de 0.5 a 11.0 µM y los ortofosfatos de 0.4 a 2.6 µM. La clorofila a en marzo presentó un valor en superficie de 7.5 mg m-3 y a 20 m de 3.5 mg m-3 , en mayo varió de 2.0 a 7.0 mg m-3 . Se concluye que la aparición de las dos especies observadas en este estudio se asocia a la disminución de los procesos de mezcla en esta bahía."

"During the period of 24 March to 14 May 2009, water and net samples were obtained for phytoplankton analyses; one aliquot was fixed in Lugol´s solution for species quantification and identification. Net samples were used for the identification of live phytoplankton species. Additionally, temperature in situ, chlorophyll a and inorganic nutrients were measured weekly in three stations. Two species were identified: Chattonella marina (Subrahmanyan) Y. Hara et Chihara and Gymnodinium catenatum Graham. Chattonella marina was the most abundant species with a density at subsurface level of 14 × 103 to 36 × 103 cell L-1 . Gymnodinium catenatum had densities were of 1 × 103 to 19 × 103 cell L-1 . Water column temperature was quasi homogeneous from surface to 20 m in depth, with an interval of 19.5 to 22.0 °C and 20.0 to 21.5 °C from March to April respectively. In the middle of May stratification of the water column initiated with a slight temperature difference of 5.0 °C recorded from surface to 20 m in depth. Nitrates varied from 0.5 to 11.0 µM and orthophosphates from 0.4 to 2.6 µM. Chlorophyll a showed a value at surface level of 7.5 mg m-3 and 3.5 mg m-3 at 20 m in March; in May chlorophyll a values ranged between 2.0 to 7.0 mg m-3 . We conclude that the presence of these two species during this study period was associated to the relaxation of the mixing processes in the zone."

Article

Chatonella marina, Gymnodinium catenatum, Bahía de La Paz, Golfo de California, fitoplancton marino Chatonella marina, Gymnodinium catenatum, Bahía of La Paz, Gulf of California, marine phytoplankton. BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ALGOLOGÍA (FICOLOGÍA)

The occurrence of yellowfin tuna (Thunnus albacares) at Espiritu Santo Seamount in the Gulf of California

ARTURO FABIAN EDUARDO MUHLIA MELO (2003)

"Pelagic fishes are not evenly dispersed in the oceans, but aggregate at distinct locations in this vast and open environment. Nomadic species such as mackerels, tunas, and sharks form assemblages at seamounts (Klimley and Butler, 1988; Fontenau, 1991). Fisherman have recognized this behavior and have placed moorings with surface buoys in deep waters to provide artificial landmarks, around which fish concentrate and are more easily captured. These fish aggregating devices (termed FADs) are common in the tropical oceans (see review, Holland, 1996). In a sense, it may only be the larger size that separates a seamount from a man-made FAD. Fish may aggregate at seamounts for very different reasons. The opportunity to feed is greater because biomass at all trophic levels, from primary producer to apex consumer, is greater than in the open ocean (Boehlert and Genin, 1987). The disturbance of flow by the seamount creates eddies downstream that retain nutrients critical to the growth of phytoplankton, and this enrichment supports a greater abundance of consumers from zooplankton to apex predators. The dipole nature of seamount magnetic fields and the outward radiating valleys and ridges of magnetic minimums and maximums might provide landmarks in oceanic landscape that fish use as a reference to guide migration (see discussion of magnetic “topotaxis” in Klimley, 1993). Yellowfin (Thunnus albacares) and bigeye (Thunnus obesus) tunas do not reside long at the Cross Seamount near Hawaii, an observation inconsistent with the theory that tunas feed on prey that remain aggregated at the site; rather their rapid passage suggests that the site is a landmark used to guide migrations (Holland et al., 1999). Adult yellowfin tuna also stay briefl y (<5 min) at FADs off Kaena Point, Oahu (Klimley and Holloway, 1999)...”

Article

yellowfin tuna, Gulf of California CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE LOCALIZACIÓN DE PECES

Adiciones a la ictiofauna de Bahía de la Paz, Baja California Sur, México.

Eduardo Francisco Balart Páez JOSE LUIS CASTRO AGUIRRE DAVID AURIOLES GAMBOA Francisco J García Rodríguez (1996)

"Se adicionan 132 nuevos registros de peces para la Bahía La Paz, y con ello se amplía a 522 el número total de especies nominales conocidas. Estos registros se basan en muestreos con redes (chinchorro y red de arrastre), observaciones sistemáticas en campos pesqueros, e identificación de oto/itas provenientes de copros de lobo marino, Zalophus californianus. La ictiofauna nerítica de Bahía de La Paz está compuesta mayoritariamente por elementos Panámicos; sin embargo, la presencia de elementos de afinidad norteña confirman a esta área como de transición. "

"One hundred thirty two new fish records are added to Bahía La Paz, making a total o! 522 nominal species reported up to day. These records are based on net sampling jgill net far enclosing and trawl net), observation of local fisheries activities, and from the identification of otoliths (sagitta) collected from sea lion's scats, Za/ophus californianus. The shore fishes of Bahía La Paz is mainly conformad by Panamic elements, but the occurrence of northern elements confirm this area as transitional one."

Article

Registros de peces marinos, Bahía de La Paz, Golfo de California, otolitos, Zalophus californianus. Marine fish records, Bahía de la Paz, Gulf of California, otoliths, Zalophus californianus. CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE PISCICULTURA PISCICULTURA

Variation in yellowfin tuna (Thunnus albacares) catches related to El Niño-Southern Oscillation events at the entrance to the Gulf of California

ARTURO FABIAN EDUARDO MUHLIA MELO ERNESTO TORRES OROZCO ARMANDO TRASVIÑA CASTRO SOFIA ORTEGA GARCIA (2006)

"Fishery catch data on yellowfin tuna (Thunnus albacares) were examined to study the effects of El Niño events between 1990 and 1999 for an area in the northeastern tropical Pacific (18−24°N, 112−104°W). The data were extracted from a database of logbook records from the Mexican tuna purse-seine fleet. Latitudinal distribution of the catches increased from south to north for the 10-year period. Highest catches and effort were concentrated between 22°N and 23°N. This area accumulated 48% of the total catch over the 10¬year period. It was strongly correlated with El Niño-Southern Oscillation (ENSO) events. At least two periods of exceptionally high catches occurred following El Niño events in 1991 and 1997. Peaks of catches were triggered by the arrival of positive anomalies of sea surface temperature (SST) to the area. A delay of two to four months was observed between the occurrence of maximum SST anomalies at the equator and peaks of catch. Prior to these two events, negative SST anomalies were the dominant feature in the study area and catch was extremely low. This trend of negative SST anomalies with low catches followed by positive SST anomalies and high catches may be attributed to northward yellowfin tuna migration patterns driven by El Niño forcing, a result that contrasts with the known behavior of decreasing relative abundance of these tuna after El Niño events in the eastern Pacific. However, this decrease in relative abundance may be the result of a local or subregional effect."

Article

yellowfin tuna, Gulf of California CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO CIENCIAS DE LA ATMÓSFERA METEOROLOGÍA MARINA

POPULATION DYNAMICS OF THE BIGEYE CROAKER MICROPOGONIAS MEGALOPS IN THE NORTHERN GULF OF CALIFORNIA

Edgar Arnoldo Arzola Sotelo CARLOS HIRAM RABAGO QUIROZ Jesús Guadalupe Padilla Serrato JUANA LOPEZ MARTINEZ ENRIQUE MORALES BOJORQUEZ (2018)

"Knowledge of biomass and demographic aspects is important in fish stock assessments. These aspects were analyzed on Micropogonias megalops in the Gulf of California, Mexico, using biological data from catches in 2010–12. Individual growth was estimated following a multi-model approach. Logistic models were used for first maturity and fishing selectivity, and natural mortality by means of empirical equations and biomass by the Pennington estimation. The results showed that the von Bertalanffy model best described growth for combined data (wi = 72.86 %), females (wi = 67.82 %) and males (wi = 69.42 %), but they showed sexual dimorphism on the species. First maturity was at 357.8 mm, fishing selectivity 323.35 and 366.35 mm for industrial and artisanal fleet, respectively, and average natural mortality of 0.51. Mean biomass was 14 412.9 tons contrasting the officially reported catch that represented only 8.7% of estimated biomass, showing evidence that M. megalops is still an underexploited resource."

Article

MICROPOGONIAS MEGALOPS, GULF OF CALIFORNIA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE DINÁMICA DE LAS POBLACIONES DINÁMICA DE LAS POBLACIONES