Direct measurement of soil chemical properties on-the-go using ion-selective electrodes

Application of FTIR Spectroscopy to Agricultural Soils Analysis

“…In addition to measurement accuracy, a key issue is the number of sampling points and the spatial resolution of the measurements. The development of "on-the-go" sensors is of primordial importance (Viscarra Rossel&McBratney 1998b) and considerable research efforts have been devoted to the development of fast, fully automated and geo-referenced measurement systems (Sibley et al 2009;Mouazen et al 2007;Christy 2008;Adamchuk et al 2004Adamchuk et al , 2005Sinfield et al 2010). Among the spectroscopy-based methods, the use of NIR has been investigated more actively, mostly due to the lower price and higher robustness of the equipment.…”

Selected highlights in American soil science history from the 1980s to the mid-2010s

“…fluorescence and mechanical impedance (Adamchuk et al, 2014(Adamchuk et al, , 2005(Adamchuk et al, , 2004Viscarra Rossel et al, 2011). These sensors have been used to identify and measure the concentrations of soil fertility indicators, different metals, carbon, carbonates, clay minerals, and iron oxides.…”

On-the-go soil sensors for precision agriculture

“…Preliminary laboratory evaluation of potassium and nitrate ion-selective electrodes showed that it is feasible to use both NO 3 − and K + ion-selective electrodes to determine soluble nitrate and potassium contents on naturally moist soil samples with the same level of errors (less than 0.3 log (K + ) or log (NO 3 − )) as soil pH (Adamchuk et al, 2003a). However, when comparing this error to the total field variability, potassium and nitrate measurements have much lower relative accuracy than soil pH.…”

“…Unlike previously described measurement concepts, electrochemical sensors require a significant amount of time for the sensing element to reach equilibrium with the measured soil or soil solution. In addition, tedious sample preparation is needed if the principal steps of conventional laboratory chemical Adamchuk et al (2003a) tests are replicated in a field sensing system. Sensor prototypes capable of accomplishing this task are relatively complex and still under development.…”