Potassium Release in an Aeric Haplaquept as Influenced by Long-Term Rice-Rice Cropping with Different Rates of Fertilizers and Manuring

作者：Srivastava Sanjay^*; Rupa T Raghavareddy; Swarup Anand

来源：Communications in Soil Science and Plant Analysis, 2013, 44(22): 3281-3292.

DOI：10.1080/00103624.2013.840839

• Calcium chloride
• citric acid
• coarse texture
• kaolinite
• potassium dynamics

Different fractions of potassium (K) and the kinetics of K release as influenced by 21 cycles of rice-rice cropping with different rates of fertilizers and manuring were investigated on an Aeric Haplaquept (kaolinitic Inceptisol) soil profile from Bhubaneswar, India. The neutral 1 N ammonium acetate-extractable K in the surface soil layer (0-15 cm) increased from its initial value of 11.2 mg K kg(-1) to 14.8, 14.2, and 17.5 mg K kg(-1) soil in different treatments. However, the nonexchangeable K content in the surface soil layer dropped considerably to a level of 4.8-20.0 mg K kg(-1) soil. Cumulative nonexchangeable K release after 121 h of extraction with 0.01 M calcium chloride (CaCl2) was <14 mg K kg(-1). The first-order kinetic model best described the nonexchangeable K release. The decrease in pH and increase in iron (Fe) content indicated the possibilities of K supply to plants through the dissolution of soil minerals.

• 出版日期2013-12-16