摘要
Knowledge on potassium ion(K^+) release from soils makes K fertilizer recommendation more efficient and profitable.Kinetics of K^+release under continuous fertilization of no fertilizer(CK), urea(N), triple superphosphate(P), and urea + triple superphosphate(NP) without K fertilizer was investigated in calcareous(chloritic and kaolinitic) soils on the Miandarband Plain in Kermanshah Province of Iran.The results showed that the kinetics of K^+release included an initial reaction and a slow reaction.The phosphateand NH_4^+-induced K^+release followed the same rate process during the rapid(2–192 h) and slow release periods(192–1 090 h).There were no significant differences in the cumulative K^+released from the chloritic and kaolinitic soils among all the treatments.The cumulative K^+released was positively correlated with P adsorption capacity for the chloritic(r = 0.461, P < 0.05) and kaolinitic soils(r = 0.625, P < 0.01), and negatively correlated with K fixation potential for the chloritic(r = 0.720, P < 0.01) and kaolinitic soils(r =-0.513, P < 0.01).There was a significant(P < 0.001) interactive effect of K fixation potential × P adsorption capacity on the cumulative K^+released for both soil groups.The initial release rate(IRR) index(a·b, where a and b are the rate coefficients of the power function equation) for the chloritic soils was significantly(P < 0.05) higher under applications of P and NP than N and CK.The IRR index values among different fertilization treatments were in the order of NP = P > N = CK for the chloritic soils, and N =P > NP > CK for the kaolinitic soils.This study showed that K fixation potential and P adsorption capacities controlled K^+release from soils.This information will be helpful for precise fertilizer recommendations for the studied soils.
Knowledge on potassium ion（K~＋） release from soils makes K fertilizer recommendation more efficient and profitable.Kinetics of K~＋release under continuous fertilization of no fertilizer（CK）, urea（N）, triple superphosphate（P）, and urea ＋ triple superphosphate（NP） without K fertilizer was investigated in calcareous（chloritic and kaolinitic） soils on the Miandarband Plain in Kermanshah Province of Iran.The results showed that the kinetics of K~＋release included an initial reaction and a slow reaction.The phosphateand NH_4~＋-induced K~＋release followed the same rate process during the rapid（2–192 h） and slow release periods（192–1 090 h）.There were no significant differences in the cumulative K~＋released from the chloritic and kaolinitic soils among all the treatments.The cumulative K~＋released was positively correlated with P adsorption capacity for the chloritic（r = 0.461, P 〈 0.05） and kaolinitic soils（r = 0.625, P 〈 0.01）, and negatively correlated with K fixation potential for the chloritic（r = 0.720, P 〈 0.01） and kaolinitic soils（r =-0.513, P 〈 0.01）.There was a significant（P 〈 0.001） interactive effect of K fixation potential × P adsorption capacity on the cumulative K~＋released for both soil groups.The initial release rate（IRR） index（a·b, where a and b are the rate coefficients of the power function equation） for the chloritic soils was significantly（P 〈 0.05） higher under applications of P and NP than N and CK.The IRR index values among different fertilization treatments were in the order of NP = P 〉 N = CK for the chloritic soils, and N =P 〉 NP 〉 CK for the kaolinitic soils.This study showed that K fixation potential and P adsorption capacities controlled K~＋release from soils.This information will be helpful for precise fertilizer recommendations for the studied soils.
出处
《Pedosphere》
SCIE
CAS
CSCD
2017年第6期1105-1115,共11页
土壤圈（英文版）
