INDICADORES ECOLÓGICOS DE LA ESTRUCTURA DE LA COMUNIDAD FITOPLANCTÓNICA EN BAHÍA CONCEPCIÓN, GOLFO DE CALIFORNIA, MÉXICO

Se presentan los cambios en la distribución espacial de la comunidad fitoplanctónica en Bahía Concepción, B.C.S. de 1991 a 1993. Se estimó la abundancia total, la variación espacio-temporal por fracciones de tamaño (nano y microfitoplancton) y se describe su estructura. Se determinaron 235 taxa, en donde las diatomeas fueron el grupo con mayor riqueza de especies (131). Los géneros más importantes fueron Chaetoceros, Rhizosolenia y Nitzschia. El segundo grupo en importancia fue el de los dinoflagelados (92 especies), representados principalmente por Protoperidinium, Ceratium y Prorocentrum; el tercer grupo fueron los silicoflagelados (9 especies), principalmente del genero Dictyocha. Las diatomeas dominaron en la temporada fría cuando la columna de agua se mantiene homogénea, en tanto que los dinoflagelados prosperaron durante la temporada cálida cuando la columna de agua estuvo estratificada. De este último grupo, 10 especies son tóxicas o potencialmente tóxicas. La abundancia fitoplanctónica total no mostró un comportamiento estacional definido, sin embargo, las variaciones interanuales mostraron un decremento de aproximadamente 25% durante 1992 y 1993, asociado con anomalías positivas de temperatura. A pesar de que las abundancias totales disminuyeron, la contribución porcentual de la fracción nanofitoplanctónica se mantuvo. Ecological indicators of the phytoplankton community structure in Bahía Concepción, Gulf of California, Mexico Seasonal changes in the spatial distribution of the phytoplankton community were determined in Bahía Concepción, B.C.S., from 1991 to 1993. The total abundance and the seasonal variations of phytoplankton size fractions (nanno and microphytoplankton) as well as its structure were determined. A total of 235 taxa were identified. Diatoms were the best represented group due to their high species richness (131). The most important genera were Chaetoceros, Rhizosolenia and Nitzschia. The second important group were dinoflagellates (92 species), represented mainly by Protoperidinium, Ceratium and Prorocentrum. The third numerically important group were the silicoflagellates (9 species). The most representative genus of this group was Dictyocha. A major presence of the diatoms was observed during the cold months with a homogeneous water-column. Major presence of dinoflagellates was recorded during the warm season when the water-column appeared stratified. Ten species of dinoflagellates were considered as toxic or potentially toxic. Total phytoplankton abundance did not show a clear seasonal pattern; nevertheless, the interannual variations exhibited an important decline of about 25 % during 1992 and 1993. These changes were related to positive anomalies of temperature. Altough phytoplankton abundance diminished, the percentage contribution of nannophytoplankton was stable.

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A MULTI-SPECIES MICROALGAE BLOOM IN BAHIA DE LA PAZ, GULF OF CALIFORNIA, MEXICO (JUNE 2008)

CICIMAR Oceánides ◽

10.37543/oceanides.v24i1.50 ◽

2009 ◽

Vol 24 (1) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

I. Gárate-Lizárraga ◽

C. J. Band-Schmidt ◽

F. Aguirre-Bahena ◽

T. Grayeb del Alamo

Keyword(s):

Phytoplankton Biomass ◽

Gulf Of California ◽

Phytoplankton Community ◽

Red Tide ◽

Total Density ◽

La Paz ◽

Gyrodinium Instriatum ◽

High Species Richness ◽

Myrionecta Rubra ◽

Ecological Importance

Red tide patches were observed in Bahía de La Paz in June 17 and 18 of 2008. According to temperature and wind data this bloom occurred under upwelling-like conditions. Examination of the red tide samples showed the ciliate Myrionecta rubra and the naked dinoflagellates Gyrodinium instriatum and Katodinium glaucum as the main species responsible for this bloom. Total density (microalgae and ciliate) at the sampling stations was similar on both days, varying from 4607 × 103 cells L-1 to 4976 × 103 cells L-1 on the first day, and from 4172 × 103 cells L-1 to 5024 × 103 cells L-1 on the second day. Phytoplankton biomass (chlorophyll a) observed during the first day of the bloom was 1.5 mg m-3. Dinoflagellates and diatoms were the most numerically important phytoplankton groups. The phytoplankton community showed a high species richness, particularly heterotrophic dinoflagellates and ebridians. The ecological importance of the heterotrophic component of naked dinoflagellates and the ebriids for this bay is discussed. Florecimiento multiespecífico de microalgas en la Bahía de La Paz, Golfo de California, México (Junio, 2008) Durante los días 17 y 18 de junio de 2008, se observó una marea roja en la Bahía de La Paz. De acuerdo con los datos de temperatura y de vientos, este florecimiento ocurrió bajo condiciones muy similares a las de una surgencia. El examen de las muestras de marea roja revelaron que el ciliado Myrionecta rubra y los dinoflagelados desnudos Gyrodinium instriatum y Katodinium glaucum fueron las principales especies responsables de esta proliferación. La densidad total (microalgas y ciliado) fue similar en ambos días, variando de 4607 × 103 céls L-1 a 4976 × 103 céls L-1 durante el primero y entre 4172 × 103 céls L-1 y 5024 × 103 céls L-1 el segundo día, respectivamente. La biomasa fitoplanctónica (clorofila a) medida durante el primer día del florecimiento fue de 1.5 mg m3. Los dinoflagelados y las diatomeas fueron los dos grupos del fitoplancton numéricamente más importantes. Se observó una comunidad fitoplanctónica con una alta riqueza de especies, particularmente de dinoflagelados y ebriidos heterotróficos. Se discute la importancia del componente heterotrófico de los dinoflagelados desnudos y ebriidos.

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BLOOM OF Gonyaulax spinifera (DINOPHYCEAE: GONYAULACALES) IN ENSENADA DE LA PAZ LAGOON, GULF OF CALIFORNIA

CICIMAR Oceánides ◽

10.37543/oceanides.v29i1.130 ◽

2014 ◽

Vol 29 (1) ◽

pp. 11

Author(s):

I. Gárate -Lizárraga ◽

Ma. S. Muñetón -Gómez ◽

B. Pérez -Cruz ◽

J. A. Díaz -Ortíz

Keyword(s):

Species Richness ◽

Gulf Of California ◽

Phytoplankton Community ◽

Seawater Temperature ◽

Low Frequency ◽

Wind Forcing ◽

La Paz ◽

Tidal Water ◽

High Species Richness ◽

Water Accumulation

During a sampling on 24 September 2012 in the coastal lagoon, Ensenada de La Paz, a small bloom of the dinoflagellate Gonyaulax spinifera was detected. Its abundance varied from 401 to 1342 × 103 cells L–1. Cells of G. spinifera ranged from 34 to 50 μm in length and 22 to 35 μm in width (n = 30). Seawater temperature and salinity were 29 °C and 35.5, respectively. The species composition of the bloom was recorded. The phytoplankton community had high species richness, resulting from a mix of benthic and pelagic diatoms and dinoflagellates, as well as cyanobacteria that occurred with low frequency. This brief proliferation lasted around three hours and may have been caused by tidal water accumulation along the shore. Although G. spinifera is a producer of yessotoxin, no fish or invertebrates were apparently killed by this bloom, which was rapidly dispersed by tides and wind-forcing. Florecimiento de Gonyaulax spinifera (Dinophyceae: Gonyaulacales) en la laguna Ensenada de La Paz, Golfo de California Durante un muestreo el 24 de septiembre de 2012 en la laguna costera Ensenada de La Paz se detectó un pequeño florecimiento del dinoflagelado Gonyaulax spinifera. Los valores de abundancia variaron de 401 a 1342 × 103 céls L–1. Los especímenes de G. spinifera presentaron un intervalo de tallas de 34 a 50 μm de longitud y de 22 a 35μm de ancho (n = 30). La temperatura del agua fue de 20 °C y la salinidad fue de 35.5. Se determinó la composición de especies durante este florecimiento. Como resultado de la mezcla de especies bentónicas y pelágicas de diatomeas y dinoflagelados, así como de algunas cianobacterias poco frecuentes, la comunidad del fitoplancton presentó una riqueza de especies alta. Esta pequeña proliferación se observó por alrededor de 3 horas y pudo ser ocasionada por la marea acumulándola en la línea de costa. Aunque G. spinifera es una especie productora de yessotoxinas, no se observaron peces ni invertebrados muertos durante este florecimiento, el cual se dispersó rápidamente por efecto de la marea y la fuerza del viento.

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Differences between Nearshore and Offshore Phytoplankton Communities in Lake Ontario

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f87-264 ◽

1987 ◽

Vol 44 (12) ◽

pp. 2155-2163 ◽

Cited By ~ 33

Author(s):

I. M. Gray

Keyword(s):

Chlorophyll A ◽

Phytoplankton Biomass ◽

Algal Biomass ◽

Phytoplankton Community ◽

Seasonal Pattern ◽

Principal Component ◽

Lake Ontario ◽

Dominant Group ◽

Phytoplankton Communities ◽

Eutrophic Species

Differences between nearshore and offshore phytoplankton biomass and composition were evident in Lake Ontario in 1982. Phytoplankton biomass was characterized by multiple peaks which ranged over three orders of magnitude. Perhaps as a consequence of the three times higher current velocities at the northshore station, phytoplankton biomass ranged from 0.09 to 9.00 g∙m−3 compared with 0.10 to 2.40 g∙m−3 for the midlake station. Bacillariophyceae was the dominant group at the northshore station until September when Cyanophyta contributed most to the biomass (83%). Although Bacillariophyceae was the principal component of the spring phytoplankton community at the midlake station, phytoflagellates (49%) and Chlorophyceae (25%) were responsible for summer biomass, with the Chlorophyceae expanding to 80% in the fall. The seasonal pattern of epilimnetic chlorophyll a correlated with temperature. While chlorophyll a concentrations were similar to values from 1970 and 1972, algal biomass had declined and a number of eutrophic species (Melosira binderana, Stephanodiscus tenuis, S. hantzschii var. pusilla, and S. alpinus) previously found were absent in 1982.

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Scyphomedusae and Ctenophora of the Eastern Adriatic: Historical Overview and New Data

Diversity ◽

10.3390/d13050186 ◽

2021 ◽

Vol 13 (5) ◽

pp. 186

Author(s):

Branka Pestorić ◽

Davor Lučić ◽

Natalia Bojanić ◽

Martin Vodopivec ◽

Tjaša Kogovšek ◽

...

Keyword(s):

Adriatic Sea ◽

Seasonal Pattern ◽

Geographical Location ◽

Distribution Patterns ◽

Mnemiopsis Leidyi ◽

Future Studies ◽

Phenological Data ◽

Pelagia Noctiluca ◽

Regional Trends ◽

Clear Seasonal Pattern

One of the obstacles to detecting regional trends in jellyfish populations is the lack of a defined baseline. In the Adriatic Sea, the jellyfish fauna (Scyphozoa and Ctenophora) is poorly studied compared to other taxa. Therefore, our goal was to collect and systematize all available data and provide a baseline for future studies. Here we present phenological data and relative abundances of jellyfish based on 2010–2019 scientific surveys and a “citizen science” sighting program along the eastern Adriatic. Inter-annual variability, seasonality and spatial distribution patterns of Scyphomedusae and Ctenophore species were described and compared with existing historical literature. Mass occurrences with a clear seasonal pattern and related to the geographical location were observed for meroplanktonic Scyphomedusae Aurelia solida, Rhizostoma pulmo, and to a lesser extent Chrysaora hysoscella, Cotylorhiza tuberculata and Discomedusa lobata. Holoplanktonic Pelagia noctiluca also formed large aggregations, which were seasonally less predictable and restricted to the central and southern Adriatic. Four species of Ctenophora produced blooms limited to a few areas: Bolinopsis vitrea, Leucothea multicornis, Cestum veneris and the non-native Mnemiopsis leidyi. However, differences between Adriatic subregions have become less pronounced since 2014. Our results suggest that gelatinous organisms are assuming an increasingly important role in the Adriatic ecosystem, which may alter the balance of the food web and lead to harmful and undesirable effects.

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Phytoplankton community of a polymictic reservoir, La Plata River basin, Uruguay

Revista Brasileira de Biologia ◽

10.1590/s0034-71081999000400002 ◽

1999 ◽

Vol 59 (4) ◽

pp. 535-541 ◽

Cited By ~ 7

Author(s):

M. C. PÉREZ ◽

S. BONILLA ◽

G. MARTÍNEZ

Keyword(s):

Spatial Heterogeneity ◽

River Basin ◽

Phytoplankton Community ◽

Water Reservoir ◽

Phytoplankton Composition ◽

Phytoplankton Abundance ◽

La Plata ◽

Phytoplankton Distribution ◽

Aulacoseira Granulata

This paper deals with the analysis of phytoplankton composition and abundance from four sampling stations at the polymictic system, Rincón del Bonete water reservoir in Uruguay. Sampling data were obtained in 4 seasonal periods between February and November 1993. A hundred and twenty-four taxa were identified, where Aulacoseira granulata (Ehrenb.) Simon., A. granulata var. angustissima (Muller) Simon., A. granulata var. angustissima f. spiralis, (Muller) Simon., A. cf. ambigua, (Grun.) Simon., A. cf.. distans (Ehrenb.) Simon., Cryptomonas spp. and Synedra ulna (Nitzsch) Ehrenberg, were always present. Phytoplankton abundance fluctuated between 29 (autumn) and 2129 (summer) ind/ml. The general dominance of Aulacoseira spp. could be related to the polymictic condition of the system. In cold months phytoplankton distribution was homogeneous among sampling stations, while in warm months, spatial heterogeneity was detected, suggesting that sampling stations can behave as independent compartments.

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Effects of CO<sub>2</sub> on particle size distribution and phytoplankton abundance during a mesocosm bloom experiment (PeECE II)

Biogeosciences ◽

10.5194/bg-5-509-2008 ◽

2008 ◽

Vol 5 (2) ◽

pp. 509-521 ◽

Cited By ~ 85

Author(s):

A. Engel ◽

K. G. Schulz ◽

U. Riebesell ◽

R. Bellerby ◽

B. Delille ◽

...

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Large Scale ◽

Phytoplankton Community ◽

Co2 Enrichment ◽

Suspended Particles ◽

Phytoplankton Abundance ◽

General Importance ◽

Co2 Treatment

Abstract. The influence of seawater carbon dioxide (CO2) concentration on the size distribution of suspended particles (2–60 μm) and on phytoplankton abundance was investigated during a mesocosm experiment at the large scale facility (LFS) in Bergen, Norway, in the frame of the Pelagic Ecosystem CO2 Enrichment study (PeECE II). In nine outdoor enclosures the partial pressure of CO2 in seawater was modified by an aeration system to simulate past (~190 μatm CO2), present (~370 μatm CO2) and future (~700 μatm CO2) CO2 conditions in triplicates. Due to the initial addition of inorganic nutrients, phytoplankton blooms developed in all mesocosms and were monitored over a period of 19 days. Seawater samples were collected daily for analysing the abundance of suspended particles and phytoplankton with the Coulter Counter and with Flow Cytometry, respectively. During the bloom period, the abundance of small particles (<4 μm) significantly increased at past, and decreased at future CO2 levels. At that time, a direct relationship between the total-surface-to-total-volume ratio of suspended particles and DIC concentration was determined for all mesocosms. Significant changes with respect to the CO2 treatment were also observed in the phytoplankton community structure. While some populations such as diatoms seemed to be insensitive to the CO2 treatment, others like Micromonas spp. increased with CO2, or showed maximum abundance at present day CO2 (i.e. Emiliania huxleyi). The strongest response to CO2 was observed in the abundance of small autotrophic nano-plankton that strongly increased during the bloom in the past CO2 mesocosms. Together, changes in particle size distribution and phytoplankton community indicate a complex interplay between the ability of the cells to physiologically respond to changes in CO2 and size selection. Size of cells is of general importance for a variety of processes in marine systems such as diffusion-limited uptake of substrates, resource allocation, predator-prey interaction, and gravitational settling. The observed changes in particle size distribution are therefore discussed with respect to biogeochemical cycling and ecosystem functioning.

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Phytoplankton abundance, dominance and coexistence in an eutrophic reservoir in the state of Pernambuco, Northeast Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652011000400018 ◽

2011 ◽

Vol 83 (4) ◽

pp. 1313-1326 ◽

Cited By ~ 9

Author(s):

Giulliari A. S. T. Lira ◽

Elcida L. Araújo ◽

Maria Do Carmo Bittencourt-Oliveira ◽

Ariadne N. Moura

Keyword(s):

Rainy Season ◽

Phytoplankton Community ◽

Dry Season ◽

Cylindrospermopsis Raciborskii ◽

Phytoplankton Abundance ◽

Vertical Variation ◽

Total Phytoplankton ◽

Physical And Chemical Variables ◽

Different Depths ◽

Physical And Chemical

The present study reports the phytoplankton abundance, dominance and co-existence relationships in the eutrophic Carpina reservoir, Pernambuco, Brazil. Sampling was carried out at six different depths bimonthly at a single reservoir spanning two climatic periods: dry season (January, September, and November 2006) and rainy season (March, May, and July 2006). Density, abundance, dominance, specific diversity and equitability of the community were determined, along with chlorophyll a, and physical and chemical variables of the environment. Eight species were considered abundant, and their densities corresponded to more than 90% of the total phytoplankton community quantified. Cyanobacteria represented more than 80% of this density. Cylindrospermopsis raciborskii was the only dominant taxon in the dry season, and was co-dominant in the rainy season. C. raciborskii, Planktothrix agardhii and Geitlerinema amphibium had the greatest densities and lowest vertical variation coefficients. The statistical analysis indicated relationships with vertical and seasonal variations in the phytoplankton community and the following variables: total dissolved solids, water temperature, electrical conductivity and pH. The changes in the environmental variables were discrete and regulated by the establishment of precipitation however, they were able to promote vertical and seasonal instability in the structure of the phytoplankton community.

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Distribución espacial y temporal del fitoplancton en el golfo de Cariaco, estado Sucre, Venezuela, febrero 2014 – enero 2015

Bulletin of Marine and Coastal Research ◽

10.25268/bimc.invemar.2018.47.2.747 ◽

2018 ◽

Vol 47 (2) ◽

Cited By ~ 1

Author(s):

Asdrúbal Calvo-Trujillo ◽

Karla Rincones-Reyes ◽

José Rafael Díaz-Ramos ◽

Brightdoom Márquez-García ◽

Sonia Subero-Pino ◽

...

Keyword(s):

Phytoplankton Community ◽

Transition Period ◽

Chlorophyll Concentration ◽

Temporal Distribution ◽

Nonparametric Analysis ◽

Multivariate Methods ◽

Phytoplankton Abundance ◽

Relaxation Period ◽

Coastal Phytoplankton ◽

First Time

Coastal phytoplankton is affected by natural and anthropic processes. To analyze the influence of some of these processes, the spatial and temporal distribution of phytoplankton in the Gulf of Cariaco, Sucre state, was evaluated. Samples (0-10 m) were collected with Niskinbottles (5 L) in seven stations between February 2014 and January 2015. Transparency (m), salinity (UPS), temperature (° C), chlorophyll concentration a (mg m-3), and phytoplankton abundance (org mL-1) were measured. A nonparametric analysis of variance and multivariate methods (PCA, CCA, and nMDS) were used to analyze the results. The 0 - 10 m stratum was homogeneous with respect to all variables except temperature which ranged from 20.1 to 29.1 °C (March and October, respectively). Temporally, the variables were heterogeneous. Biomass fluctuated between undetectable (ND) and 17.5 mg m-3 (December and March). While microalgal abundance oscillated between 0.24 and 1.85 x 103 org mL-1 (April andFebruary). The community was dominated by diatoms, nanoflagellates, and coccolithophorids. The first two groups were associated with turbulent, nutrient-rich waters. The nMDS separated the community into the three periods previously described for the region. Likewise, the CCA detected that wind speed and temperature were the most influential variables on the phytoplankton community during upwelling and relaxation period, respectively. In the transition period, none of the variables studied affected the community. This is the first time that coccolithophores are reported as part of the dominant flora in the Gulf of Cariaco. This change suggests modifications in the oceanographic conditions of the study area.

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ESTIMACIÓN DE LA PRODUCTIVIDAD PRIMARIA EN DOS BAJOS DE LA PARTE SUR DEL GOLFO DE CALIFORNIA, MÉXICO

CICIMAR Oceánides ◽

10.37543/oceanides.v23i1-2.43 ◽

2008 ◽

Vol 23 (1-2) ◽

pp. 39

Author(s):

G. Verdugo-Díaz ◽

R. Cervantes Duarte ◽

M. O. Albáñez-Lucero

Keyword(s):

Surface Temperature ◽

Water Column ◽

Primary Productivity ◽

Gulf Of California ◽

Inorganic Nutrients ◽

Water Transparency ◽

Vertical Profiles ◽

Subsurface Maximum ◽

Natural Fluorescence ◽

Productivity Estimation

Primary productivity estimation in two seamounts in the southern Gulf of California, México Vertical profiles of temperature and natural fluorescence from 100 m deep were made during February 2005. Water transparency was measured using Secchi’s disc, as well samples of superficial water and at maximum of fluorescence deep were collected to analyze inorganic nutrients. In “El Bajo Espiritu Santo” temperature (20 °C at surface) diminished gradually with depth, without significant stratification.Primary productivity shows superficial values close to 6 mg C m-3 h-1, recahing undetectable values at 20 m of depth. In “El Bajo Gorda” surface temperature reached 22 °C and the water column shows a thermocline between 35 m and 45 m of depth. The profiles of primary productivity presented a subsurface maximum (approximately 2 mg C m-3 h-1) associated with the thermocline.

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Seasonal changes of steroid concentrations in seminal plasma of a European wild boar

Acta Endocrinologica ◽

10.1530/acta.0.1070425 ◽

1984 ◽

Vol 107 (3) ◽

pp. 425-427 ◽

Cited By ~ 15

Author(s):

D. Schopper ◽

J. Gaus ◽

R. Claus ◽

H. Bader

Keyword(s):

Wild Boar ◽

Seminal Plasma ◽

Seasonal Pattern ◽

Plasma Concentrations ◽

Boar Taint ◽

Steroid Production ◽

European Wild Boar ◽

Clear Seasonal Pattern ◽

Boar Semen ◽

Low Levels

Abstract. The influence of season on testicular steroid production as a parameter of testicular function has been studied in a wild boar. Semen was collected once weekly while it served the dummy. In seminal plasma concentrations of the following steroids were determined by radioimmunoassay: unconjugated testosterone, conjugated testosterone, unconjugated total oestrogens, conjugated total oestrogens and 5α-androst-16-en-3-one ('boar-taint steroid'). All steroids showed a clear seasonal pattern with highest concentrations in autumn and early winter and low levels from January to July. Maxima during the rutting season were 10–25 times greater than average values out of season. During a 2-month-period (mid-July until mid-September) libido was abolished and the wild boar refused to mount the dummy. These results indicate that the seasonal variation in testicular steroid production by the wild boar, regulated by photoperiod, are similar to those of the domestic boar.

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