Variación diurna del fitoplacton y los factores abióticos en un estanque camaronícola salobre en el sur de Sinaloa, México

Abstract

Short-term changes in the phytoplankton and the abiotic factors were studied during one 24 h period (30-31 Januray, 1992) collecting samples each two hours at the waters input and one 7.3 ha pond a commercial semi-intensive shrimp farm near Mazatlán Harbor, Sinaloa, México. The observed variations of phytoplankton were in concordance with the dominant taxonomoic group (cyanophytes), while that the dinoflagellates showed a similar variation that the described for zooplankton by several authors. Diatoms, although to be the group less abundant was also more diverse and do not showed a defined pattern. The mean abundance was two times more elevated in the pond than the estero in relation to cyanophites, and 35 times more in dinoflagellates. The diurnal fluctuations of pH, temperature, dissoved oxygen and chlorophyll a exhibited a defined pattern, contrary to the behavior of nutrients, wich the chemical dominant form of nitrogen was the ammonia and the levels of dissolved inorganic phosphate were always below of 0.25 uM.