不同覆盖方式下山地澳洲坚果园对磷利用的影响研究

Effects of Different Mulching Patterns on Utilization of Soil Phosphorus in the Hill Macadamia Orchard

为解决10年以上山地澳洲坚果种植园磷利用效率在持续降低的现象,采用腐熟的澳洲坚果皮及地膜为覆盖材料,连续2年对澳洲坚果园磷利用相关的指标进行观测研究。结果表明:与对照相比,覆盖2年后,澳洲坚果树冠下地膜覆盖和覆盖果皮均可以提高根系生物量,而覆盖果皮可显著提高类蛋白根的发生量及细根生物量,显著增加细根在根系中的比重;随着覆盖时间的延长,覆盖果皮可显著降低果园土壤总磷的含量,提高澳洲坚果树叶片磷的含量,降低土壤速效磷的浓度,即增强了土壤有效磷的转化效率,对照及覆膜处理下果园总磷含量及有效磷含量均有升高趋势,而叶片磷含量却趋向降低;覆盖果皮可显著提高澳洲坚果座果率及产量,覆膜处理反而降低了澳洲坚果座果率和产量。该研究表明,澳洲坚果皮覆盖可作为山地澳洲坚果园有益的管理措施。

The paper aims to solve the problem that some mature orchards of ten years and older have become inefficient in absorbing phosphorus fertilizers. In this study, the author took mature macadamia husk and plastic film mulching as the material, and investigated the utilization of phosphorus in hill macadamia orchard for two consecutive years. The results showed that, compared with the control, macadamia orchard mulched with macadamia husk and plastic film mulching could improve root biomass, and mulched with macadamia husk could significantly increase the generation rate of proteoid roots and fine root biomass, significantly increase the proportion of fine root in roots. With the extension of mulching time, the macadamia husk could significantly reduce the total phosphorus content of macadamia orchard soil, improve the phosphorus content of macadamia leaf, reduce the concentration of soil available phosphorus, and enhance the conversion efficiency of soil available phosphorus. Soil phosphorus content and soil available phosphorus content had an increasing trend under both plastic film mulching and the control, but the phosphorus content of leaves had a reducing tendency. Mulching with macadamia husk could significantly improve the rate of fruit and macadamia nut production, but the macadamia fruit set and yield were reduced by plastic film mulching. This research suggests that husk mulching should be a useful management approach in hill macadamia orchard.