https://digitalcommons.calpoly.edu/nres_rpt/14
Date of Award
9-2021
Degree Name
MS in Environmental Sciences and Management
Department
Natural Resources Management
College
College of Agriculture, Food, and Environmental Sciences
Advisor
Christopher Surfleet
Advisor Department
Natural Resources Management
Advisor College
College of Agriculture, Food, and Environmental Sciences
Abstract
Estuaries are coastal confluences with innumerable ecosystem services. With the continuous change in land use including the increasing number of people moving to live in coastal areas and on-going agricultural operations, these coastal systems are being adversely impacted. Climate change is also negatively affecting estuaries. Subsequently, this research study assessed the water quality, monthly, at three different locations of three bar-built estuaries in the Central Coast of California. Water quality was evaluated by the change in chlorophyll-a, nitrogen, phosphorus, pH, temperature, dissolved oxygen, and specific conductivity over the course of 19 months. The eutrophication potential and the role of open and closed estuary conditions and impact on water quality of these three bar-built estuaries were also evaluated. The change in parameter trends illustrated that the estuaries have varied dissolved oxygen conditions, including having or approaching hypoxic conditions in some parts of the year, and that on various occasions water temperature surpasses the threshold for sensitive fish. Over half of the total grab samples results for chlorophyll-a and orthophosphate as phosphorus indicated that all three estuaries have moderate and high eutrophication potential. Open and closed estuary conditions seemed to affect dissolved oxygen concentrations and pH. The lowest dissolved oxygen concentrations and the highest pH values were measured when the estuaries were closed.