T6713 sensitivity to CO2 – Discussion

While the sensor provides over estimations of soil CO2 it can detect sharp differences when varying amounts of NaHCO3 are added. The sensor showed higher CO2 peaks in the lab in comparison to the field. This suggests that the sensor is sensitive to abiotic factors, such as wind speed. With additional time, investigations into correlations between abiotic factors and CO2 accumulation would have been conducted. While the lowest concentration of NaHCO3 added was 1g, it is possible that the sensor could detect differences in CO2 accumulation at even lower concentrations. Further studies would have investigated this to develop a finer sensitivity scale for the T6713 CO2 sensor.

In contrast to the field 3g and 5g NaHCO3 treatments, 1g shows a steady increase over time with only a minute drop in CO2 concentrations while the sensor records a decline in CO2 concentrations over time for the other treatments. Under normal conditions, CO2 levels are approximately 550ppm, according to the sensor. The peak for the 1g treatment is roughly 640ppm which isn’t significantly different from normal conditions therefore any drop in CO2 isn’t as extreme as the 3g or 5g treatments.

Lab measurements however show far greater peaks due to less disturbances from the external environment. While the 1g treatment shows a normal distribution of CO2 over time, 3g and 5g treatments peak early and drop immediately after. This may be due to the chemical reaction between the acid and NaHCO3 peaking rapidly, producing a lot of CO2 all at once and then dropping significantly as the reaction slows down and CO2 begins to saturate over time.