监测和研究黑土磷素盈亏状况及有效磷演变规律,可为黑土肥力的培育、磷资源的持续利用与合理施肥提供科学依据.本文研究了常规施肥条件下18个黑土监测点土壤磷盈亏情况及其有效磷含量的变化.结果表明,常规施肥条件下,磷肥年平均用量为23.29 ～49.93 kg P·hm-2,作物吸磷量年平均为21.54 ～45.52 kg P·hm-2,年均当季土壤表观磷盈亏大小为-13.33 ～14.99 kg P·hm-2.土壤磷盈亏不同导致其有效磷的变化不同,39％的监测点有效磷含量显著升高,年增加速率为0.68 ～5.10mg·kg-1;50％的监测点有效磷呈持平状态;11％的监测点有效磷显著下降.经相关性分析,各监测点有效磷的变化量与土壤累积磷呈显著正相关关系,土壤每盈余100 kg P·hm-2,有效磷可增加5.28 mg·kg-1.磷肥施用量为36 kg P·hm-2时土壤表观磷盈亏为零.因此,在有效磷水平为15 ～50 mg·kg-1黑土上种植玉米,可将36 kg P·hm-2作为推荐磷肥用量.
Soil Phosphorus Balance and Changes of Olsen-P of Black Soil under Long-term Conventional Fertilization
Phosphorus (P) budget and changes of Olsen-P in black soil were explored to provide a scientific basis for the cultivation of soil fertility,the sustainable use of P resources and the rational application of P fertilizer.Soil P budgets and changes of soil Olsen P were studied,based on 18 monitoring sites under conventional fertilization condition.The results showed that the average of P application rate ranged from 23.29 kg P· hm-2 to 49.93 kg P· hm 2,annual crop P uptake from 21.54 kg P· hm-2 to 45.52 kg P· hm-2,and soil apparent phosphorus budgets from-13.33 kg P· hm-2 to 14.99 kg P · hm-2.The different P budgets in sites led to the conspicuous difference in the changes of soilOlsen-P:significant increase of Olsen-P in 39％ of the soils by O.68 ～ 5.10 mg·kg-1 · a,fiat state in 50％ of soils,significant decrease in 11％ of soils.There is a significant positive correlation between changes of Olsen-P and soil accumulated P,and with an average surplus of 100 kg P·hm-2,the soil Olsen-P increased by 5.28 mg,kg-1.Soil apparent phosphorus budget was zero at a rate of 36 kg P·hm-2.So 36 kg P·hm-2 could be recommended as reasonable P application rate when use maize as the main crop in black soil with the content of Olsen-P from 15 mg· kg-1 to 50 mg· kg-1.
国家科技期刊平台
NSTL
万方数据
维普
