外源磷及腐植酸施用方式对灰漠土有效磷含量的影响

Effect of Outer-source Phosphorus Usage and Application Ways on the Contents of Available Phosphorus in Gray Desert Soil

通过室内培养方法,研究外源磷不同用量及腐植酸施用方式对灰漠土有效磷含量的影响。结果表明:随外源磷用量增加,土壤有效磷含量先增大后减小,土壤固磷率先增后减再增大,有效磷含量在土壤中有一个极大值平衡点;腐植酸及外源磷施用方式对土壤有效磷含量影响较大,单施腐植酸或单施外源磷均可增加土壤有效磷含量,且效果显著;腐植酸与外源磷的合理搭配施用,使土壤有效磷含量大于单施外源磷和单施腐植酸的方式;在腐植酸与外源磷施用过程中,先施外源磷再施腐植酸,土壤有效磷含量增加速度最快、土壤有效磷含量最高,差异达到显著水平。

The effect of outer-source phosphorus usage and the application ways of humic acid on the content of available phosphorus in gray desert soil were studied in a laboratory.The results show that the content of soil available phosphorus was increased at first and then decreased with the increase of outer-source phosphorus usage,and the soil phosphorus fixation rate was increased at first,and then decreased,but increased again with the increase of outer-source phosphorus usage.There was a maximum balance point of available phosphorus in soil.The effect of application ways of outer-source phosphorus and humic acid on soil available phosphorus content was significant.Soil available phosphorus content could be significantly increased by applying humic acid or outer-source phosphorus.The effect of rational application of combining humic acid and outer-source phosphorus on soil available phosphorus content was more significant than that by applying outer-source phosphorus or humic acid only.Soil available phosphorus content could be increased most effectively by applying outer-source phosphorus at first and then humic acid.