Identifying rainfall effects in an arid Gulf of California coastal lagoon

• Published in: Journal of environmental management Vol. 75; no. 2; pp. 183 - 187
• Main Authors: Mendoza-Salgado, Renato A., Lechuga-Devéze, Carlos H., Ortega-Rubio, Alfredo
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.04.2005; Elsevier; Academic Press Ltd
• Subjects: Acid rain; Animal, plant and microbial ecology; Applied ecology; Arid coastal lagoon; Arid zones; Biological and medical sciences; California; Coastal areas; coasts; Conservation, protection and management of environment and wildlife; Desert Climate; Disturbing pulse; Environmental management; Environmental Monitoring; Evaluation; Fundamental and applied biological sciences. Psychology; General aspects; Gulf of California; hydrochemistry; hydrologic models; Measurement; nitrogen; Nitrogen - analysis; phosphorus; Phosphorus - analysis; Precipitation; Rain; Rainfall; Rainfall measurement; salinity; Seasons; Sodium Chloride - analysis; U.S.A; Water - chemistry; water balance; Water quality; wetlands; Mexico; California; Gulf of California; Pacific Ocean; North Pacific; ISE, Mexico, Baja California Sur, Ensenada de la Paz; Mexico, Baja California Sur, Ensenada de la Paz; Mexico, California Gulf; ISE, Mexico, California Gulf; Gulf of California; Rainfall; Disturbing pulse; Arid coastal lagoon; Brackish water environment; Environmental management; Coastal lagoon
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2004.10.008

At Ensenada de La Paz, a coastal lagoon on the western side of the Gulf of California, nutrient and salinity data before and after rain events were evaluated using a mass balance model to estimate the exchange of conservative and non-conservative variables with the adjacent sea. Surface salinity, nitrogen (N–NO 3, N–NO 2), and phosphorus (PO 4) were used in the model to obtain the hydraulic balance, water residence time, and nitrogen and phosphorus fluxes. Results showed that residual volume was mainly influenced by evaporation. Rainfall and runoff increased the mixed volume and reduced water residence time. Pre-rainfall hydraulic balance conditions were reestablished about 10 days after a rainstorm. Rainwater inputs also modified the quality of the coastal lagoon: the pre-rainfall scenario showed that more nitrogen is consumed than produced, and there is a phosphorus sufficiency. A rain disturbance induces a nitrogen and phosphorus increase. Eleven days after a rainstorm, nitrogen and phosphorus levels did not return to the pre-rainfall scenario. Rain disturbances in arid zone coastal lagoons modify their water quality and exchange with the adjacent ocean; some management strategies are suggested.