|Title||Microfluidic Leaching of Soil Minerals: Release of K+ from K Feldspar|
|Publication Type||Journal Article|
|Year of Publication||2015|
|Authors||Ciceri, D, Allanore, A|
The rate of K+ leaching from soil minerals such as K-feldspar is believed to be too slow to provide agronomic benefit. Currently, theories and methods available to interpret kinetics of mineral processes in soil fail to consider its microfluidic nature. In this study, we measure the leaching rate of K+ ions from a K-feldspar-bearing rock (syenite) in a microfluidic environment, and demonstrate that at the spatial and temporal scales experienced by crop roots, K+ is available at a faster rate than that measured with conventional apparatuses. We present a device to investigate kinetics of mineral leaching at an unprecedented simultaneous resolution of space (similar to 10(1)-10(2) mu m), time (similar to 10(1)-10(2) min) and fluid volume (similar to 10(0)-10(1) mL). Results obtained from such a device challenge the notion that silicate minerals cannot be used as alternative fertilizers for tropical soils.