Evaluating benthic flux measurements from a gradient flux system

Multiple methods exist to measure the benthic flux of dissolved oxygen (DO), but many are limited by short deployments and provide only a snapshot processes occurring at sediment–water interface. The gradient (GF) method measures near bed gradients DO estimates eddy diffusivity from existing turbulence closure solve for flux. This study compares measurements seagrass, reef, sand environment with two other methods, covariance chambers, highlight strengths, weaknesses, uncertainty being made. results show three major areas primary importance when using GF method: (1) sufficient is critical use this sensor precision variability; (2) it important similar comparing across sites or time, as showed good agreement were often biased larger smaller based on method; (3) in complex bottom types, length scale placement sensors can lead large sources error. Careful consideration these potential errors needed method, properly addressed, high may prove useful tool measuring long-term fluxes chemical constituents interest that incompatible methods.