Potassium fixation capacity of some highly calcareous soils as a function of clay minerals and alternately wetting-drying

ABSTRACT

The current research was done to investigate the effect of wetting-drying cycles, time, and clay mineralogy on K fixation capacity of highly calcareous soils. In order to conduct the study, eight soil samples were collected. The samples were treated with different concentrations of K including 200 (K1), 400 (K2) and 800 mg kg⁻¹ (K3) and 8 different incubation time including 6 h (t1), 24 h (t2), 72 h (t3), one week (t4), two weeks (t5), one month (t6), two months (t7) and three months (t8). Also, a wetting-drying treatment was done (td) in order to simulate the effect of irrigation and soil drying on K fixation. The results showed that for all K levels addition, the percentage of fixed K was increased with time. The K fixation content was increased with the increase in the added K from K1 to K3, while K fixation percentage was decreased. The results also showed that there was a significant difference between soils with wetting-drying treatment (td) and soils with three-month incubation (t8) in K fixation capacity, so that the fixation of K by the soils was increased with wetting-drying cycles.

KEYWORDS:

• K fixation
• alternately wetting-drying
• K levels
• clay minerals

Acknowledgments

The authors appreciate Shiraz University for providing research facilities.

Disclosure statement

No potential conflict of interest was reported by the authors.