Microfluidic Leaching of Soil Minerals: Release of K+ from K Feldspar.
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 (~101-102 μm), time (~101-102 min) and fluid volume (~100-101 mL). Results obtained from such a device challenge the notion that silicate minerals cannot be used as alternative fertilizers for tropical soils.
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America.
Davide
D
Ciceri
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America.
Antoine
A
Allanore
D000383:Agriculture / Q000379:methods*; D000538:Aluminum Silicates; D005308:Fertilizers; D044085:Microfluidics; D018517:Plant Roots; D017680:Potassium Compounds; D012987:Soil
D000538:Aluminum Silicates; D005308:Fertilizers; D017680:Potassium Compounds; D012987:Soil; C016447:feldspar