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对连续覆盖雷竹林换叶期林地土壤和叶片养分利用效率、养分再吸收效率进行了研究,旨在阐明地表连年覆盖栽培对雷竹林养分利用特征的影响。结果表明:连续覆盖3年雷竹林土壤N养分有效性、N素利用效率以及再吸收效率均显著性提高,雷竹林表现出较高的保存N养分的能力;土壤P元素有效性水平显著升高,而叶片P养分的利用效率显著降低,反映出叶片对土壤高P含量的适应策略,N、P养分利用效率之间存在显著的负相关关系(P<0.05);土壤K元素的有效性水平显著降低,竹林通过提高自身的K再吸收效率来维持养分的正常循环,再吸收效率高达95.8%;不同覆盖年限雷竹林Nm/Pm均<14,连续覆盖3年雷竹林Nm/Pm比值极显著下降,经推断是此时雷竹林对土壤有效P高吸收的结果。成熟叶片的Nm/Pm与N、P的再吸收效率均无显著相关性,Nm/Pm并不能很好地反映叶片在凋落前的养分再分配格局。
This paper studied the nutrient use efficiency and nutrient reabsorption efficiency of soil and leaves in continuous replanting of Phyllostachys pubescens forest so as to clarify the effect of surface mulching over successive years on the nutrient utilization characteristics of Phyllostachys praecox. The results showed that the availability of N nutrients, N use efficiency and reabsorption efficiency were significantly increased in the three years of continuous succession. Phyllostachys pubescens showed higher ability of preserving N nutrients, and P availability of soil was significantly higher (P <0.05). However, the utilization efficiency of P nutrition in leaves was significantly reduced, which indicated that there was a significant negative correlation between leaf adaptation strategies of high P content and N, P utilization efficiency (P <0.05) The bamboo reforestation maintained normal circulation of nutrients by increasing its K reabsorption efficiency, and the reabsorption efficiency was as high as 95.8%. The Nm / Pm of Phyllostachys pubescens forest with different coverage years was <14, and the Nm / Pm ratio of Phyllostachys pubescens forest for 3 years coverage was extremely significant Decline, it is inferred that Phyllostachys pubescens P available on the soil at this high absorption results. There was no significant correlation between Nm / Pm and N, P resorption efficiency of mature leaves. Nm / Pm did not reflect the pattern of nutrient redistribution before leaf litter.