不同有机物料与部分化肥长期定位配合施用对土壤养分的调控效应

Effect of long-term fixed application of different material replacing partly chemical nitrogenous fertilizer on soil nutrition in dry land of eastern Gansu province

为了明确有机物料替代部分化肥长期定位施用对冬小麦连作农田土壤养分的调控效应。在陇东黄土旱塬进行连续11年的定位试验,比较不施肥(CK)、施用等量氮磷养分的3种有机物料(生物有机肥、秸秆还田、农家肥)与氮磷化肥配施的农田土壤养分含量变化。结果显示:2016年冬小麦收获后,相比于CK,施用有机肥明显增加了0~60 cm土层硝态氮积累量,而有机质、全量氮磷钾及其速效养分含量在0~60 cm土层范围内随土层深度增加逐渐降低,且0~20 cm土层为硝态氮、有机质、全量氮磷钾及速效氮、磷富集区。从0~20 cm土层平均养分含量来看,施用有机肥显著提高了土壤有机质、全氮、全磷、全钾、碱解氮、有效磷、速效钾含量。其中生物有机肥处理11年土壤有机质、全氮、全磷、全钾、碱解氮、有效磷、速效钾含量分别较CK提高了18.39%、11.49%、15.62%、2.76%、14.94%、143.25%、36.33%,农家肥处理分别提高了14.42%、14.94%、14.06%、2.84%、10.87%、100.7%、41.58%,秸秆还田分别提高了7.20%、10.34%、9.38%、1.46%、9.24%、54.66%、8.82%。因此,在陇东半湿润偏旱雨养农业区,采用化肥与有机肥配施,兼顾钾肥的施肥措施是最合理的施肥方式,有利于保持黑垆土养分平衡,促进农田生产力稳定可持续。

In order to clarify the effect of long-term fixed application of chemical nitrogen partly replaced by different organicnitrogen on soil nutrition in winter wheat continuous cropping, a successive 11-year field test with same winter wheat cultivarwas conducted in loessial soil areas in eastern Gansu province of the Loess Plateau. The change of soil nutrient content wascompared with no fertilizer （CK）, applied equal amount of nitrogen and phosphorus nutrient with three kinds of organic materi-al （biological organic fertilizer, straw returned and farmyard manure） or nitrogen and phosphorus fertilizer. The resultsshowed that compared with CK, the organic fertilizer significantly increased the 0 ~ 60 cm soil NO-3 -N accumulation amountafter winter wheat harvest in 2016. The amount of organic matter, total and available N, P, K content within 0 ~ 60 cm soillayer decreased gradually with the increase of soil depth, and 0 ~ 20 cm soil layer had the highest contents of nitrate nitrogen,organic matter, total and available nitrogen and phosphorus. Based on the average soil nutrient content in 0 ~ 20 cm soil layer,organic fertilizer significantly increased the soil organic matter, total nitrogen, total phosphorus, total potassium, availablenitrogen, available phosphorus and available potassium content. Compared with CK, the soil organic matter, total nitrogen,total phosphorus, total potassium, available nitrogen, available phosphorus and available potassium content increased by18, 39%, 11, 49%, 15, 62%, 2, 76%, 14, 94%, 143, 25%, 36, 33%, respectively, for manure, increased by14, 42%, 14, 94%, 14, 06%, 2, 84%, 10, 87%, 100, 7%, 41, 58%, respectively, for the biological organic fertilizer,and increased by 7, 20%, 10, 34%, 9, 38%, 1, 46%, 9, 24%, 54, 66%, 8, 82%, respectively for the straw return.Therefore, in the study area, combined application of organic fertilizer and chemical fertilizer, especially potash fertilizer canbe the most reasonable fertilization option, which can maintain the soil nutrient balance and promote the soil productivity.