• ISSN 1008-505X
  • CN 11-3996/S

不同覆盖方式对马铃薯−小麦轮作土壤养分表观平衡的影响

Effects of mulching methods on soil nutrient apparent balance under wheat-potato rotation system in the rain-fed area

    摘要
  • 摘要:
    目的 通过研究陇中旱地不同覆盖方式下土壤养分表观平衡状况及其与土壤养分之间的关系，探索适于陇中地区的覆盖模式，为减少化肥投入、提高农民收入和农业可持续发展提供依据。
    方法 2022—2023年在甘肃省农业科学院定西试验站开展田间试验，采用单因素随机区组设计，种植制度为马铃薯−小麦轮作。设无覆盖对照(CK)、地膜覆盖(PM)、秸秆碎秆覆盖还田(SR)、秸秆带状覆盖还田(SM) 4个处理，采集两年成熟期马铃薯和小麦的植株和土壤样品进行分析。
    结果 与CK相比，PM、SR和SM 3种覆盖措施提高了马铃薯和小麦植株氮、磷、钾积累量，以PM处理效果最佳，马铃薯植株中氮、磷、钾积累量增幅分别为41.44%、71.99%、49.78%，小麦植株中增幅分别为38.37%、59.70%、64.59%。SR和SM处理提高了土壤中速效养分含量，SR处理的提升效果大于SM处理，该处理下马铃薯季0—20 cm土层土壤碱解氮、速效磷、速效钾含量分别提高了39.31%、14.99%、25.92%，20—40 cm土层土壤速效磷和速效钾含量分别提高了31.97%和15.72%。在小麦季，0—20 cm土层土壤碱解氮和速效钾含量分别提高了21.36%和21.16%，20—40 cm土层土壤速效磷和速效钾含量分别提高了12.03%和14.29%，40—60 cm土层土壤速效磷和速效钾含量分别提高了39.46%和30.67%。CK处理两年土壤养分表观平衡均为氮、磷大量盈余，钾素亏缺。与CK相比，PM处理N、P盈余量分别显著降低了37.38%和27.30%，钾亏缺量增加了60.73%，氮、磷、钾实际平衡率分别为48.0%、106.3%、−94.1%；SR处理氮、磷盈余量分别增加了89.97%和43.75%，钾亏缺量减少了88.18%，实际平衡率分别为159.5%、241.3%、−7.2%；SM处理氮、磷、钾盈余量分别增长了99.19%、46.27%、120.12%，实际平衡率分别为180.6%、255.7%、16.0%。
    结论 陇中旱地农田现有施肥量和管理措施下，土壤养分表观平衡均表现为氮磷盈余、钾亏缺。地膜覆盖可有效提高作物养分积累量和粗蛋白产量，降低氮磷盈余量，但加剧钾素亏缺。秸秆碎秆覆盖还田和秸秆带状覆盖还田增加作物养分吸收量和粗蛋白产量的效果虽低于地膜覆盖，并加剧了土壤氮磷盈余量，但缓解了钾素的亏缺量。因此，陇中旱地农田长期采用秸秆覆盖措施时应考虑降低氮、磷肥的施用量，采用地膜覆盖措施时应注意提高钾肥的施用量。

     

    Abstract:
    Objectives We studied the apparent balance of soil nutrients under different mulching methods in dryland of central Gansu, to provide a scientific basis for nutrient management under mulching cultivation.
    Methods A field experiment was carried out at Dingxi Experimental Station of Gansu Academy of Agricultural Sciences in 2022 and 2023, where the planting system was one crop each year under potato and wheat rotation. The experiment was composed of four treatments: no mulching control (CK), plastic film full mulching (PM), crushed straw mulching and returning to field (SR), and whole straw mulching on strip and returning to field (SM). Potato and wheat samples were collected at harvesting stages for analysis of biomass, nutrient contents. Soil samples were collected at the same time for measurement of available nutrient contents.
    Results Compared with CK, all the PM, SR and SM treatments increased the absorption of N, P, and K by potato and wheat, and PM treatment was recorded the highest absorption with the increment of N, P, and K in potato plants by 41.44%, 71.99% and 49.78%, and in wheat plants by 38.37%, 59.70% and 64.59%, respectively. Both SR and SM treatments increased the soil available nutrient contents, and improvement effect in SR treatment was greater than that of SM treatment. In potato season, SR treatment increased available N, P and K in 0−20 cm soil layer by 39.31%, 14.99% and 25.92%, respectively, and increased available P and K in 20−40 cm soil layer by 31.97% and 15.72%, respectively, and in wheat season, increased 0−20 cm soil layer available N and K by 21.36% and 21.16%, increased 20−40 cm soil layer available P and K by 12.03% and 14.29%, increased 40−60 cm soil layer available P and K by 39.46% and 30.67%, respectively. In CK treatment, the apparent balances of soil N and P were in surplus, and that of K was in deficit in two rotation seasons. PM treatment significantly reduced soil N and P surplus by 37.38% and 27.30%, but exaggerated the K deficit by 60.73%, with the actual balance rate of N, P, and K at 48.0%, 106.3%, and −94.1%, respectively. The apparent N and P surpluses of SR treatment were 89.97% and 43.75% higher than CK, while the K deficit was 88.18% lower than CK, with the actual balance rates of N, P, and K at 159.5%, 241.3%, and −7.2%. The apparent N, P, and K of SM treatment were all in surplus, which were 99.19%, 46.27%, and 120.12% higher than CK, with the actual balance rate of 180.6%, 255.7%, and 16.0%.
    Conclusions The apparent balance of soil N, and P were in heavily surplus, while that of K was in deficit under the local nutrient management in the potato-wheat rotation system in dryland farmland of central Gansu. Plastic film mulching effectively decreases the P and P surplus but exaggerate the unbalance of K. Straw mulching in full and strip pattern could increase the absorption of N, P and K by crops, the crude protein yield of crops, in spite of that, they still increase the N and P surplus, and alleviates the deficiency of potassium. Therefore, the long-term use of straw mulching in dryland farmland in central Gansu should consider reducing the application rate of nitrogen and phosphorus fertilizer, and plastic film mulching should pay attention to increasing the application rate of potassium.

     

    • HTML全文
    • 参考文献(38)
    • 相关文章
    • 施引文献
  • 资源附件(0)

/

返回文章
返回