Caracterización de la variabilidad diaria de parámetros químicos del agua en el desarrollo de procesos de larvicultura de camarón (Penaeus vannamei).

Abstract

Currently, atmospheric CO2 levels are the highest they have been in the past 800,000 years. As the concentration of this gas continues to increase, ocean acidification becomes an increasingly urgent and concerning problem. Ecuador is the leading producer of shrimp in Latin America, and this industry represents the second most important source of income after oil. The country's trajectory in aquaculture production is well-established, which has developed efficient protocols. However, the effects that ocean acidification will have on this sector in the short and long term are still unknown. This study was developed with the objective of analyzing daily fluctuations in the chemical parameters associated with ocean acidification in the cultivation of shrimp larvae (Penaeus vannamei), as a basic tool to understand the current state of management in this sector of aquaculture. We found that throughout the day, pH in zoea and mysis presents its lowest averages at 4:00 PM (7.77 and 7.78) and the highest at 8:00 AM (7.79), while in postlarvae, daily variation did not show significant differences; temperature showed significant differences in zoea and mysis, where their lowest averages were at 8:00 AM (34.36 and 34.27) and the highest at 4:00 PM (35.03 and 34.94), salinity did not show significant differences throughout the day in any of the stages, and oxygen only presented significant differences in the daily variability of mysis with its lowest averages at 8:00 PM and 12:00 AM (3.79) and its highest at 12:00 PM (4.12). Additionally, it was found that pH remained stable (7.82 ± 0.07) throughout the cultivation cycle; however, total alkalinity (AT) progressively increased from 2458.75 ± 203.43 units in pre-seeding to 3663.25 ± 123.97 units in the post-larval stage. This increase in AT would be related to the management of ion equilibrium processes that take place throughout the cultivation. Additionally, despite pCO2 levels reaching 1152.35 ± 415.38, the biocompatible forms of calcium carbonate (calcite and aragonite) remained within suitable ranges for the development of organisms.