Mechanism of Potassium Release from Different Silicate Minerals by Releasing K Bacteria in Northwest Arid Land, China
SHANG Hai-li;BI Yin-li;PENG Su-ping;XIE Wen-wu;State Key Laboratory of Coal Resource and Safety Mining, China University of Mining & Technology (Beijing);Institute of Mines Engineering, Inner Mongolia University of Science and Technology;
To explore potential fertility of soil and utilized coefficient of soil water, it is researched that potassium release from soil minerals by releasing K bacteria with different inoculation amounts and water contents in static culture. Releasing K bacteria is inoculated in illite and feldspar substrates, which are the main soil minerals in northwest arid land. The changes of mineral morphology, structure and composition are tested by Fourier Transform Infrared Spectroscopy(FTIR), Transmission Electron Microscopy(TEM) and Energy Disperse Spectroscopy(EDS). Results show that silicate bacteria C6 X has significant effect on potassium release from feldspar and illite, which is effected by water and inoculation amount. The appropriate inoculation conditions are 15% of inoculation amount, 70% of moisture content for feldspar and 20% inoculation amount, 70% of moisture content for illite. Feldspar is dissolved by releasing K bacteria, potassium content, and Si/Al are both low. It is showed that the releasing K bacteria can not only release potassium from feldspar, but also dissolve Si which is used for their own growth. Interlayer charge of illite is reduced by releasing K bacteria; divalent cations are released from alumina octahedral; interlayer charge is lower, which cause the release of K + ions and adsorbed water. FTIR of illite shows that the release of K is associated with the release of interlayer water. Therefore, the further study on Si and Fe element migration from soil clay minerals by releasing K bacteria, and interaction between interlayer K element and water molecules has important ecological significance.