Estuarine Autonomous Instrumentation Platform and MERHAB
This new method of sampling was developed for the St. Johns River in northeast Florida. The Monitoring and Event Response for Harmful Algal Blooms (MERHAB) program began in 1999 and was a 3-year, comprehensive study of the lower St. Johns River estuary.
One of the problems with many sampling programs, including those for harmful algal blooms, is obtaining representative samples from the area of interest. Often, few data points are used to represent long time periods or a large geographic area. The limiting factors are usually resources (time and personnel) and logistics. Therefore, this type of "spot-sampling" misses most of the high-frequency variability in aquatic ecosystems. Many programs are now using continuously recording instrumentation in the field. These remote sensors allows specific variables to be measured at short intervals for an extended period.
We have contracted AMJ Equipment Corp of Lakeland, Florida, to design and build a platform with continuously recording instrumentation aboard. The platform is mounted on a pontoon boat deck, which permits safe and convenient maintenance and portability among sites. This autonomous platform will be deployed in the St. Johns River in northeast Florida. A datalogger controls the sampling intervals of the sensors and stores the data. A volumetric sampler can collect whole water samples for analysis in the laboratory. Various sensors are connected to a flow-through sample system that can draw water from three depths. Onboard sensors will measure several water column variables including relative fluorescence, nitrate, phosphate, water temperature, dissolved oxygen, pH, salinity, and turbidity. The platform will also have a meteorological package, light sensors (ambient and underwater), a current meter, and a tide gauge. Data can be transmitted to a home base via a GOES-satellite or cell phone.
We are excited about obtaining this type of high-frequency water quality data that will help us understand the complex interactions of water quality, harmful algal blooms, and, possibly, fish-disease events. Also, this is currently the most extensive sensor array on a remote platform in Florida. The platform is currently in the water and in the testing stage.
This project is made possible by the National Aeronautics and Space Administration (NASA) and the Florida Fish and Wildlife Conservation Commission (FWC).
