An improved datalogger and novel probes for continuous redox measurements in wetlands.

In soils and sediments, the redox potential (Eh) is an important parameter controlling the persistence of many organic and inorganic compounds. Especially in wetlands, fluctuations in redox potential values can be very large and depth dependent. For this reason, field deployable logging systems have previously been developed, yet these systems were limited in several aspects. Here we report the development of an improved multichannel datalogger (HYPNOS) and two novel probes for continuous monitoring of Eh profiles, and briefly illustrate the potential applications. The combination of a multichannel logger with different types of probes allows characterisation of spatial and temporal variability of redox potential in relation to environmental and ecological parameters, and we expect this will greatly enhance our knowledge of the functioning of wetlands.