We have developed a sensing system that utilizes a low-cost computer (Raspberry Pi) and its imaging camera as an optical sensing core for the continuous detection of NO₂ in the air (PiSENS-A).

Field-deployable sensors play an important role in precision agriculture and are used to enable key stakeholders (farmers, agronomists, policy makers, etc.) to make informed decisions about resource management and improve crop yields. Sensor developers must consider technological, economic, and human aspects jointly in order to design a successful sensor. The objective of this review is to describe some of the key strands of each aspect and highlight the need to develop a degree of understanding of all of these aspects in order to create technologies that will be easily and readily adopted. Rather than analyzing each area in depth, we limit our discussion to a few major aspects and try to indicate interdependency and showcase their impact on one another. We hope that this approach will instigate thoughts and ideas and stimulate the co-creation of fit-for-purpose sensors.

Under the predicted climate change scenarios, heavy precipitation could result in prolonged flooding (PF) and flooding-drying (FD) of soils in agriculture. The influence of PF and FD on soil greenhouse gas fluxes and nitrogen (N) dynamics of arable and grassland soils, which are the dominant land use types in UK soil, is still unclear. Two months of soil incubation experiments were conducted to find out the impact of PF and FD on soil nitrogen dynamics and greenhouse gas fluxes from arable and grassland soil. The result showed the developed ion selective electrodes (ISE) sensor was working to measure NH4+ in the first 5 days of real-life application under both grassland and arable soil. There were less N2O-N emissions in grassland and arable soil when soil moisture was higher than 100% water-holding capacity (WHC). Arable soil had more N2O-N emissions when soil moisture was higher than 100% WHC compared to grassland soil due to a low pH. Grassland soil had more N2O-N emissions when soil moisture was lower than 100% WHC compare to arable soil due to a high carbon and nitrogen source. When soil moisture was greater than 100% WHC, the available NO3--N in the soil controlled N2O-N emissions of grassland more effectively. The N2O-N emissions of grassland soil were more controlled by soil stable NH4+-N and NO3--N when soil moisture was lower than 100% WHC. The emissions of N2O-N and CO2-C were increased with the time of FD. FD significantly increased N2O-N, CO2-C, and CH4-C emissions in grassland soil compared to arable soil by 0.93, 2.15, and 37.29 times, respectively. Converting arable land use to grassland could increase the greenhouse gas (GHG) emissions under climate change (heavy rain). Further research needs to be done to find out how to reduce the GHG emissions under climate change after transfer arable to grassland.