California, mexico

We describe water quality in two hypersaline negative estuaries in the Northern Gulf of California, along the coast of Sonora, Mexico, over a two-year period. In the Northern Gulf, non-mangrove salt marshes known as esteros (negative estuaries) cover 134, 623 ha. Esteros are characterized by an extreme tidal range, higher salinity at their head than at their mouth due to high evaporation, limited freshwater input and a mixed semi-diurnal tidal regime. Between 2005 and 2007, we sampled surface temperature, dissolved oxygen, salinity, pH, depth, chlorophyll, nutrients (NH+4, NO3 ̄, NO2 ̄, and PO4), and total suspended solids across one wetland, Estero Morúa. We also led a participatory monitoring effort, where oyster farmers took daily measurements of surface temperature, salinity, pH, and dissolved oxygen in both Estero Morúa (31°17 ́09” N; 113° 26 ́19” W) and Estero Almejas (31°10 ́15” N; 113°03 ́53” W). These sites allow comparisons between distinct habitats and levels of oceanic influence. Estero Morúa is a high energy lagoon with a narrow mouth and a prominent permanent channel restricted by spits, while Almejas is an open bay with a large intertidal mudflat. Among the main findings are 1) Surface temperatures follow a seasonal pattern, with highest temperatures in June to September and lowest from December to February. 2) Low rainfall and runoff together with high seawater input and evaporative loss results in high salinities. 3) High dissolved oxygen concentrations and low nutrient levels are indicative of the recharge rate between the wetlands and the sea, and are characteristic of oligotrophic systems. It is likely that The exclusive license for this PDF is limited to personal printing only. No part of this digital document may be reproduced, stored in a retrieval system or transmitted commercially in any form or by any means. The publisher has taken reasonable care in the preparation of this digital document, but makes no expressed or implied warranty of any kind and assumes no responsibility for any errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of information contained herein. This digital document is sold with the clear understanding that the publisher is not engaged in rendering legal, medical or any other professional services. Hem Nalini Morzaria-Luna, Abigail Iris-Maldonado and Paloma Valdivia-Jiménez. 202 residence time and tidal dynamics are the main factors dictating the physicochemical dynamics of these systems.