土壤改良剂对酸性水稻土pH值、交换性钙镁及有效磷的影响

The effects of acid soil modifiers on soil pH, exchangeable calcium and exchangeable magnesium,and available phosphorus in acid paddy soils

选取酸性水稻土进行土壤培养试验和水稻盆栽试验,分别施用生石灰(Q)、白云石粉(DP)、钙镁磷肥(CMP)以及土壤改良剂1号(M1)、2号(M2)、3号(M3)和4号(M4),分析其土壤pH值、交换性钙、交换性镁、有效磷含量的变化,探讨土壤改良剂对酸性水稻土理化性质的影响。结果表明,与不施改良剂(CK)比较,使用改良剂均显著提高了土壤pH(P<0.05);Q、DP和M2处理交换性钙含量增加显著(P<0.05),DP、M2、M3和M4处理交换性镁含量增加显著(P<0.05);M1、M3和M4处理显著降低了有效磷含量(P<0.05)。盆栽试验与土培试验相比较,施相同改良剂的土壤pH、交换性钙、镁、有效磷的变化幅度差异大,交换性钙含量除M3处理降低4.9%外,其余处理均升高,升高最多的有20.9%;交换性镁含量除DP处理升高14.9%外,其余均下降,M2处理降低最多,为9.2%;所有处理有效磷含量均升高,增加最多是M2处理,达114.6%。研究阐明了土壤改良剂在短期内能够影响土壤pH值、交换性钙、镁、有效磷含量的变化,但土培和盆栽两种方式造成的效果有差异。

Soil incubation experiment and rice-growing pot experiment were conducted to investigate the changes of soil pH, exchangeable calcium and magnesium, and available phosphorus in the treatments of the non-amendment （CK） and the amendments of quicklime （Q）, dolomite powder （DP）, calcium magnesium phosphate （CMP） and four soil modifiers of No.1 （M1）, No.2 （M2）, No.3 （M3） and No.4 （M4） in acid paddy soils. The results of the incubation experiment showed that all treatments increased soil pH compared with CK （P〈0.05）; Q, DP and M2 increased the soil exchangeable calcium significantly （P 〈0.05）; DP, M2, M3 and M4 improved the soil exchangeable magnesium significantly （P 〈0.05）; and M1, M3 and M4 reduced the soil available phosphorus significantly （P〈0.05）. To compare with incubation experiment, the results of the pot experiment showed that the soil modifiers improved soil pH, exchangeable calcium and magnesium, and available phosphorus better than in the incubation experiment. Except for the M3 treatment with the soil exchangeable calcium decreasing by 4.9%, all other amendment treatments increased the soil exchangeable calcium, and the most increased by 20.9%. In addition to DP increased by 14.9%, the others＇ exchange magnesium contents were all decreased, to reduce the most was the M2 treatment by 9.2%. All treatments＇ available phosphorus contents were increased, the most increased by 114.6% and was M2 treatment. Our collective experimental data suggested that the soil modifiers can affect soil pH, exchangeable calcium and magnesium, and available phosphorus of the acid paddy soils for the short term and they performed differently in the incubation and pot experiments.