Spatial and temporal assessment of water quality in the lagoon systems of Sinaloa, Mexico, of international importance (Ramsar )

Abstract

Lagoon systems are recognized for their environmental importance and for providing ecosystem services to all species. Some have wetland ecosystems recognized as Ramsar sites. The state of Sinaloa, in northwestern Mexico, has nine such sites of international importance. Given the state's hydrology and the intensity of primary activities in the watersheds, this research focuses on evaluating the spatial and temporal distribution of water quality in the most representative lagoon-wetland systems in Sinaloa. To this end, the certified CONAGUA database was used, with at least four sampling points in each lagoon system and records from 2012 to 2022. The database was processed using Google Colab, which was also used to generate spacial graphs and perform Pearson's correlation analysis. The results indicated that water exchanges with the Pacific Ocean allow high levels of dissolved oxygen and, therefore, oxidation of both carbonaceous and nitrogenous organic matter. However, for phosphorus, a 0.7 correlation with turbidity was found, which is associated with sediment resuspension and high siltation rates. It was also evident that salinity fluctuations are remarkably constant over time, which may indicate that they are due to hydrodynamic rather than anthropogenic effects. It is recommended that this study be expanded to include variables from other environmental matrices to determine whether pollutants from river basins have accumulated at river mouths before interacting with Pacific Ocean currents.