Automatic and manual in-situ chamber measurements for open-channel respiration in streams and rivers

River corridors are widely understood to be important locations for organic matter processing and aerobic respiration, however it remains unclear where in the river corridor these processes primarily occur, how variable processing rates are in space and time, what conditions provide the primary drivers of spatial and temporal variability, and how quickly they respond to external perturbations, both natural and anthropogenic. One of the major reasons for this large knowledge gap is the lack of tools and techniques available. We propose a pair of simple tools for measuring open-channel respiration in streams and rivers. One is a manual system that collects single data points, while the other is an automated system designed to take repeated measurements over time, generating a time series of open channel respiration measurements. Both of these devices can be paired with open channel dissolved oxygen time series inverse modeling to parse ecosystem respiration into open channel and sediment-associated fractions. We present preliminary data indicating that these devices both generate useful data in at least some stream types, though the minimum open channel respiration rate detection limits are not yet well characterized.