Primer estudio de la productividad primara de Laguna Sauce Grande

La productividad primaria (PP) en los sistemas acuáticos refiere a la tasa de incorporación de carbono inorgánico, principalmente por parte del fitoplancton, primer eslabón de la trama trófica. La materia orgánica resultante queda disponible para los siguientes eslabones de la cadena (zooplancton, peces). El estudio de la PP de la laguna Sauce Grande es de interés por su uso recreativo y pesquero.Área: Ciencias Biológicas, Ambiente y Salu

Dynamics of the phytoplankton community of an Argentine Pampean wetland in relation to water environmental variables

Background. Shallow lakes are an essential component of the Argentine Pampean wetlands. The Sauce Grande shallow lake is a typical water body of the Argentine Pampean wetlands, based on its shallow characteristics and its homogeneity in terms of physical, chemical, and biological characteristics. Phytoplankton is dominant in the turbid shallow lake and is sensitive to internal fluctuations in the water body and prevailing environmental conditions that affect its abundance and distribution. Goals. We conducted a temporal and spatial analysis of the distribution and abundance of the phytoplankton community in the Sauce Grande shallow lake (province of Buenos Aires, Argentina), from April to September 2012, in order to study the influence of physicochemical variables of the water on phytoplankton. Methods. We undertook Cluster Analysis (CA), Principal Component Analyses (PCA) and Spearman correlations between the biotic and physicochemical variables recorded at two sites of the shallow lake. Results. The multivariate analysis showed that certain water physicochemical factors (conductivity, depth, pH, turbidity, and temperature) profoundly influenced the phytoplankton dynamics, giving rise to a seasonal succession of community species, with a clear dominance of Cyanobacteria. The Spearman correlation showed that Cyanobacteria relate positively and significantly to conductivity whereas Chlorophyta and Bacillariophyta relate negatively and significantly to temperature, pH, conductivity, and salinity. Chlorophyta was the group with the highest number of recorded taxa while Cyanobacteria constituted the largest group, the most abundant species being Synechocystis salina Wislouch. Conclusions. The results obtained in this study demonstrate that the phytoplankton community of the Sauce Grande shallow lake is highly susceptible to changes in water environmental conditions, in particular to water level fluctuations, and to conductivity, pH, and temperature.Background. Shallow lakes are an essential component of the Argentine Pampean wetlands. The Sauce Grande shallow lake is a typical water body of the Argentine Pampean wetlands, based on its shallow characteristics and its homogeneity in terms of physical, chemical, and biological characteristics. Phytoplankton is dominant in the turbid shallow lake and is sensitive to internal fluctuations in the water body and prevailing environmental conditions that affect its abundance and distribution. Goals. We conducted a temporal and spatial analysis of the distribution and abundance of the phytoplankton community in the Sauce Grande shallow lake (province of Buenos Aires, Argentina), from April to September 2012, in order to study the influence of physicochemical variables of the water on phytoplankton. Methods. We undertook Cluster Analysis (CA), Principal Component Analyses (PCA) and Spearman correlations between the biotic and physicochemical variables recorded at two sites of the shallow lake. Results. The multivariate analysis showed that certain water physicochemical factors (conductivity, depth, pH, turbidity, and temperature) profoundly influenced the phytoplankton dynamics, giving rise to a seasonal succession of community species, with a clear dominance of Cyanobacteria. The Spearman correlation showed that Cyanobacteria relate positively and significantly to conductivity whereas Chlorophyta and Bacillariophyta relate negatively and significantly to temperature, pH, conductivity, and salinity. Chlorophyta was the group with the highest number of recorded taxa while Cyanobacteria constituted the largest group, the most abundant species being Synechocystis salina Wislouch. Conclusions. The results obtained in this study demonstrate that the phytoplankton community of the Sauce Grande shallow lake is highly susceptible to changes in water environmental conditions, in particular to water level fluctuations, and to conductivity, pH, and temperature

Productividad, estado trófico y dinámica fitoplanctónica en la laguna Sauce Grande y su afluente homónimo (pcia. de Buenos Aires, Argentina)

The shallow lake Sauce Grande is located in the southwest of Buenos Aires province. It is a widening of the Sauce Grande River that flows in and out of the lake. The aim of this study is to estimate for the first time the primary productivity (PP) of this lake and to contrast the physiochemical variables, phytoplankton structure and trophic status with those of its main tributary. Monthly samplings (April-September 2014) were performed in the middle basin of the river and on the coast of the lake. We recorded in situ physical and chemical parameters with a multisensor Horiba U-10. Phytoplankton samples were collected with a plankton net for the qualitative study and with plastic bottles for quantitative analysis.The greatest physicochemical differences corresponded to turbidity and conductivity with values of 581.3 NTU and 9 mS/cm for the lake and 17.7 and 1.7, for the river. The average PP in the lake was 252.1 mg C/m3.h. Cyanobacteria were the most abundant taxonomic group in both systems, although its abundance was greater in the shallow lake. The Carlson index, based on the concentration of chlorophyll a and total phosphorus, identifies the lake as eutrophic, while the river was classified as oligo-mesotrophic according to the same variables. Our results suggest that the Sauce Grande Lake is an autotrophic system with a highly productive metabolism. The remaining production becomes biomass and accumulates within the system, in the form of high levels of phytoplankton abundance, in particular a massive proliferation of Cyanobacteria

Evolución del estado trófico y estructura del fitoplancton de un lago somero de la región pampeana: laguna Sauce Grande (Pcia. de Buenos Aires, Argentina)

La laguna Sauce Grande está ubicada en el suroeste de la provincia de Buenos Aires, Argentina, con el río Sauce Grande como afluente y efluente de la misma. El objetivo de este trabajo fue evaluar el estado trófico y las características de la comunidad del fitoplancton de esta laguna. Las muestras de fitoplancton se recolectaron mensualmente y también se midieron los parámetros físico-químicos. El estado trófico del cuerpo de agua se estimó con el índice de estado trófico de Carlson (TSI) basado en la concentración de clorofila a. Bacillariophyta fue el grupo de algas más ampliamente representado en número de taxones para todo el período estudiado. A su vez, Cyanobacteria fue el grupo dominante con Synechocystis salina Wislouch como la especie dominante. La concentración de clorofila a osciló entre 64,6 y 769,4 mg/m3. La abundancia total de fitoplancton varió de 1,6 × 106 a 5,2 × 106 ind /ml y el biovolumen varió de 9,4 × 107 a 1,4 × 109 μm³/ml. La concentración de clorofila a se correlacionó significativamente con la abundancia de fitoplancton, pero no se correlacionó significativamente con el biovolume. Además, el TSI (Cl a) de Carlson osciló entre 70 y 97. En consecuencia, el lago somero Sauce Grande se clasificó como hipertrófico para el período estudiado 2012-2013, mientras que el estado del cuerpo de agua se determinó como eutrófico para el otoño de 2010.Sauce Grande shallow lake is located in the Southwest of the Buenos Aires Province, Argentina, with the river Sauce Grande as both affluent and effluent of it. The aim of this work was to evaluate the trophic state and the characteristics of the phytoplankton community of this shallow lake during an annual cycle. Phytoplankton samples were collected monthly and also physico-chemical parameters were measured. The trophic state of the water body was estimated with Carlson Trophic State Index (TSI) based on chlorophyll a concentration. Bacillariophyta was the algal group most widely represented in number of taxa for the entire studied period. In turn, Cyanobacteria was the dominant group with Synechocystis salina Wislouch as the dominant species. Chlorophyll a concentration ranged between 64.6 and 769.4 mg/m3. The total phytoplankton abundance ranged from 1.6×106 to 5.2×106 ind/ml and the biovolume varied from 9.4×107 to 1.4×109 μm³/ml. The chlorophyll a concentration was significantly correlated with phytoplankton abundance but it was not significantly correlated with biovolume. Besides, Carlson’s TSI (Cl a) ranged from 70 to 97. Accordingly, the Sauce Grande shallow lake was classified as hypertrophic for the studied 2012-2013 period, whereas the status of the water body was determined as eutrophic for the autumn of 2010

Evolución del estado trófico y estructura del fitoplancton de un lago somero de la Región Pampeana: laguna Sauce Grande (provincia de Buenos Aires, Argentina)

Sauce Grande shallow lake is located in the Southwest of the Buenos Aires Province, Argentina, with the river Sauce Grande as both affluent and effluent of it. The aim of this work was to evaluate the trophic state and the characteristics of the phytoplankton community of this shallow lake during an annual cycle. Phytoplankton samples were collected monthly and also physico-chemical parameters were measured. The trophic state of the water body was estimated with Carlson Trophic State Index (TSI) based on chlorophyll a concentration. Bacillariophyta was the algal group most widely represented in number of taxa for the entire studied period. In turn, Cyanobacteria was the dominant group with Synechocystis salina Wislouch as the dominant species. Chlorophyll a concentration ranged between 64.6 and 769.4 mg/m3. The total phytoplankton abundance ranged from 1.6×106 to 5.2×106 ind/ml and the biovolume varied from 9.4×107 to 1.4×109 μm³/ml. The chlorophyll a concentration was significantly correlated with phytoplankton abundance but it was not significantly correlated with biovolume. Besides, Carlson’s TSI (Cl a) ranged from 70 to 97. Accordingly, the Sauce Grande shallow lake was classified as hypertrophic for the studied 2012- 2013 period, whereas the status of the water body was determined as eutrophic for the autumn of 2010.Facultad de Ciencias Naturales y Muse

Evolución del estado trófico y estructura del fitoplancton de un lago somero de la Región Pampeana: laguna Sauce Grande (provincia de Buenos Aires, Argentina)

Sauce Grande shallow lake is located in the Southwest of the Buenos Aires Province, Argentina, with the river Sauce Grande as both affluent and effluent of it. The aim of this work was to evaluate the trophic state and the characteristics of the phytoplankton community of this shallow lake during an annual cycle. Phytoplankton samples were collected monthly and also physico-chemical parameters were measured. The trophic state of the water body was estimated with Carlson Trophic State Index (TSI) based on chlorophyll a concentration. Bacillariophyta was the algal group most widely represented in number of taxa for the entire studied period. In turn, Cyanobacteria was the dominant group with Synechocystis salina Wislouch as the dominant species. Chlorophyll a concentration ranged between 64.6 and 769.4 mg/m3. The total phytoplankton abundance ranged from 1.6×106 to 5.2×106 ind/ml and the biovolume varied from 9.4×107 to 1.4×109 μm³/ml. The chlorophyll a concentration was significantly correlated with phytoplankton abundance but it was not significantly correlated with biovolume. Besides, Carlson’s TSI (Cl a) ranged from 70 to 97. Accordingly, the Sauce Grande shallow lake was classified as hypertrophic for the studied 2012- 2013 period, whereas the status of the water body was determined as eutrophic for the autumn of 2010.Facultad de Ciencias Naturales y Muse

Productividad, estado trófico y dinámica fitoplanctónica en la laguna Sauce Grande y su afluente homónimo (pcia. de Buenos Aires, Argentina)

The shallow lake Sauce Grande is located in the southwest of Buenos Aires province. It is a widening of the Sauce Grande River that flows in and out of the lake. The aim of this study is to estimate for the first time the primary productivity (PP) of this lake and to contrast the physiochemical variables, phytoplankton structure and trophic status with those of its main tributary. Monthly samplings (April-September 2014) were performed in the middle basin of the river and on the coast of the lake. We recorded in situ physical and chemical parameters with a multisensor Horiba U-10. Phytoplankton samples were collected with a plankton net for the qualitative study and with plastic bottles for quantitative analysis.The greatest physicochemical differences corresponded to turbidity and conductivity with values of 581.3 NTU and 9 mS/cm for the lake and 17.7 and 1.7, for the river. The average PP in the lake was 252.1 mg C/m3.h. Cyanobacteria were the most abundant taxonomic group in both systems, although its abundance was greater in the shallow lake. The Carlson index, based on the concentration of chlorophyll a and total phosphorus, identifies the lake as eutrophic, while the river was classified as oligo-mesotrophic according to the same variables. Our results suggest that the Sauce Grande Lake is an autotrophic system with a highly productive metabolism. The remaining production becomes biomass and accumulates within the system, in the form of high levels of phytoplankton abundance, in particular a massive proliferation of Cyanobacteria.Facultad de Ciencias Naturales y Muse

Productividad, estado trófico y dinámica fitoplanctónica en la laguna Sauce Grande y su afluente homónimo (pcia. de Buenos Aires, Argentina)

The shallow lake Sauce Grande is located in the southwest of Buenos Aires province. It is a widening of the Sauce Grande River that flows in and out of the lake. The aim of this study is to estimate for the first time the primary productivity (PP) of this lake and to contrast the physiochemical variables, phytoplankton structure and trophic status with those of its main tributary. Monthly samplings (April-September 2014) were performed in the middle basin of the river and on the coast of the lake. We recorded in situ physical and chemical parameters with a multisensor Horiba U-10. Phytoplankton samples were collected with a plankton net for the qualitative study and with plastic bottles for quantitative analysis.The greatest physicochemical differences corresponded to turbidity and conductivity with values of 581.3 NTU and 9 mS/cm for the lake and 17.7 and 1.7, for the river. The average PP in the lake was 252.1 mg C/m3.h. Cyanobacteria were the most abundant taxonomic group in both systems, although its abundance was greater in the shallow lake. The Carlson index, based on the concentration of chlorophyll a and total phosphorus, identifies the lake as eutrophic, while the river was classified as oligo-mesotrophic according to the same variables. Our results suggest that the Sauce Grande Lake is an autotrophic system with a highly productive metabolism. The remaining production becomes biomass and accumulates within the system, in the form of high levels of phytoplankton abundance, in particular a massive proliferation of Cyanobacteria.Facultad de Ciencias Naturales y Muse

Productividad, estado trófico y dinámica fitoplanctónica en la laguna Sauce Grande y su afluente homónimo (pcia. de Buenos Aires, Argentina)

The shallow lake Sauce Grande is located in the southwest of Buenos Aires province. It is a widening of the Sauce Grande River that flows in and out of the lake. The aim of this study is to estimate for the first time the primary productivity (PP) of this lake and to contrast the physiochemical variables, phytoplankton structure and trophic status with those of its main tributary. Monthly samplings (April-September 2014) were performed in the middle basin of the river and on the coast of the lake. We recorded in situ physical and chemical parameters with a multisensor Horiba U-10. Phytoplankton samples were collected with a plankton net for the qualitative study and with plastic bottles for quantitative analysis.The greatest physicochemical differences corresponded to turbidity and conductivity with values of 581.3 NTU and 9 mS/cm for the lake and 17.7 and 1.7, for the river. The average PP in the lake was 252.1 mg C/m3.h. Cyanobacteria were the most abundant taxonomic group in both systems, although its abundance was greater in the shallow lake. The Carlson index, based on the concentration of chlorophyll a and total phosphorus, identifies the lake as eutrophic, while the river was classified as oligo-mesotrophic according to the same variables. Our results suggest that the Sauce Grande Lake is an autotrophic system with a highly productive metabolism. The remaining production becomes biomass and accumulates within the system, in the form of high levels of phytoplankton abundance, in particular a massive proliferation of Cyanobacteria.The shallow lake Sauce Grande is located in the southwest of Buenos Aires province. It is a widening of the Sauce Grande River that flows in and out of the lake. The aim of this study is to estimate for the first time the primary productivity (PP) of this lake and to contrast the physiochemical variables, phytoplankton structure and trophic status with those of its main tributary. Monthly samplings (April-September 2014) were performed in the middle basin of the river and on the coast of the lake. We recorded in situ physical and chemical parameters with a multisensor Horiba U-10. Phytoplankton samples were collected with a plankton net for the qualitative study and with plastic bottles for quantitative analysis.The greatest physicochemical differences corresponded to turbidity and conductivity with values of 581.3 NTU and 9 mS/cm for the lake and 17.7 and 1.7, for the river. The average PP in the lake was 252.1 mg C/m3 .h. Cyanobacteria were the most abundant taxonomic group in both systems, although its abundance was greater in the shallow lake. The Carlson index, based on the concentration of chlorophyll a and total phosphorus, identifies the lake as eutrophic, while the river was classified as oligo-mesotrophic according to the same variables. Our results suggest that the Sauce Grande Lake is an autotrophic system with a highly productive metabolism. The remaining production becomes biomass and accumulates within the system, in the form of high levels of phytoplankton abundance, in particular a massive proliferation of Cyanobacteria

Caracterización del fitoplancton y estado trófico de la laguna Sauce Grande (provincia de Buenos Aires, Argentina) en el otoño de 2010

The composition and abundance of the phytoplankton in the Sauce Grande Shallow Lake were studied during the autumn of 2010. Three sampling sites were established: In the output Sauce Grande River (E1), at the entrance of the Sauce Grande River in the water body (E2) and in the deepest sector of the water body (E3). Sixty taxa were identified, belonged to Chlorophyta (50%), Heterokontophyta (27%), Cyanobacteria (20%) and Dinophyta/Euglenophyta (3%). Phytoplankton abundance ranged between 84500 and 340600 ind/ml. No differences were observed in total phytoplankton abundances among sampling stations, but significant differences among sampling dates were found. Planctonema lauterbornii Schmidle (Chlorophyta) was the dominant species with abundances up to 70600 ind/ml. Several salinity indicators (as Chaetoceros muelleri, Cyclotella aff. meneghiniana and Protoperidinium achromaticum) and eutrophication indicators (as Microcystis aeruginosa and Pediastrum boryanum) were registered. Besides, representatives of Cyanobacteria putative toxic-bloom producers (as species of Anabaena, Anabaenopsis, Aphanocapsa and Microcystis) were identified. This shallow lake is classified as eutrophic according to Carlson TSI based on chlorophyll a. The high phytoplankton abundance and the low Secchi disk readings allow defining the Sauce Grande Shallow Lake as “turbid” and phytoplankton dominated.Instituto de Limnología "Raúl A. Ringuelet