Summary: | Memoria de tesis doctoral presentada por Rigoberto Rosas Luis para optar al grado de Doctor en Ciencias del Mar por la Facultad de Geología de la Universitat de Barcelona (UB), realizada bajo la dirección de la Dra. Pilar Sánchez Zalacain del Institut de Ciències del Mar (ICM-CSIC) y del Dr. Cesar A. Salinas Zavala del Centro de Investigaciones Biológicas del Noroeste, S.C. La Paz, México [EN] The interactions, between species and environmental variables such as sea surface temperature (SST), salinity, primary production (Chlorophyll a) and variations of biomass estimates of zooplankton, were evaluated in order to know the impact that the environmental variables can produce in the squid species. I. argentinus and D. gigas squid species were used as models because of the availability of fishery and biomass data. Both species are Ommastrephids squids and they are abundant in the ocean, also they are important resources in the fishery activity. The environmental variables were tested using time series analysis, defining the trend and cycles, this analysis eliminated the set data of salinity, because no change was observed in the time series. We observed a positive trend in the SST series and changes along the series were observed. These changes were identified as seasonal (summer-winter), interannual (El Niño-La Niña) and interdecadal (cold and warm periods). El Niño and La Niña events were related with the positive and negative tendency of the chlorophyll a and zooplankton. The gradual warming of the water masses in everyone cycle of the SST and the availability of nutrients produced a decrease in the primary production that was represented during 1990-1992, 1994-1996 and at the end of 1997 to 2000. These periods correspond to the El Niño event characterized by an increase in the SST. [.] [ES] La interacción entre las especies y las variables ambientales como la temperatura superficial del mar (TSM), la salinidad, la productividad primaria (Clorofila a) y las variaciones de la biomasa del zooplancton fueron ...
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