Persistent Monitoring of Dissolved Oxygen for Investigations of Biogeochemical Cycles Across the Terrestrial-Aquatic Ecosystem Interface

Environmental sensor networks capable of taking data quickly enough to capture minute-scale fluctuations and durable enough to capture these data for entire seasons provide essential information for studying the seasonal and annual effects of environmental activity across complete ecosystems. The models informed by this data are useful for predicting both short- and long-term changes to economically important coastal ecosystems. Distributed sensors for dissolved oxygen (DO) concentration measurement in coastal marine settings are of particular interest because of the important role DO plays in catalyzing a diversity of environmentally important biogeochemical reactions. However, commercially available DO sensors are not suited for long-term or in situ measurements in marine environments. How this Problem or Situation is Being Addressed: We are developing dissolved oxygen sensors that are suitable for long-term and in-situ measurements in terrestrial, aquatic, and marine environments. What was done in Phase I: In Phase I of this work we have developed and successfully deployed the beginnings of a distributed dissolved oxygen sensing network. The deployments have included dockside locations and installation into deployable benthic flux chambers. We have also developed and used a submersible data logger. What is planned for the Phase II project: In Phase II of this project we will continue the development of our probes and scale up our production methods, with the goal of market entry within two years. We will instrument an entire iverine/estuarine/marine ecosystem and expand our deployment capabilities to deep marine applications. Commercial Applications and Other Benefits: Dissolved oxygen measurements provide critical information for many areas, including water-quality assessment, groundwater contamination modeling, industrial-process control, and the management of fisheries. Improvements in sensing technology that improve performance and reduce cost will benefit these areas directly. These technological developments will also enable the deployment of marine ecosystem-scale sensing networks that will provide information critical to the improvement of predictive ecosystem models. These ecosystem models guide our efforts to protect economically important coastal marine ecosystems.