Chemical sensors allow the determination of the chemical composition of their environment. The sensor translates the concentration of a chemical species (also termed analyte) into a quantifiable physical signal. Chemical Sensors allow the production of spatially and temporally high resolution datasets over a wide variety of regions. They are typically based in situ, and are highly mobile, and cost efficient compared to manual environmental sampling and lab based analysis. The knowledge of chemical concentrations within the water column (both freshwater and saltwater), can be used to help understand the processes occurring. For example, within the “Hydrological Extremes” event chain, the hypothesised consequences of the extreme rainfall is increased nutrient input from fertile top soils stimulating eutrophication events. In situ sensors allow the characterisation of the nutrient run-off in such regions and more detailed evaluation of river and lake “health”.
Ideally, sensors are highly flexible and able to work equally well in both freshwater and salt water environments. This supports the highly modular nature of MOSES, and allows the scientists to have access to near real-time data. However, in situ sensors are relative new and development time is required to bring the sensors to an acceptable technology ready level for both fresh and salt water. Therefore, as well as purchasing and working with commercial sensors for specific environments, the MOSES project will also work to develop sensors to quantify hard-to-measure analytes, such as trace elements and nutrients, through lab-on-a-chip sensors. These sensors miniaturise typical lab procedures into instruments that are deployable on different platforms to be used in the MOSES project such as Gliders, Moorings, and Landers.