海南热带次生林恢复过程中凋落物及土壤水源涵养功能变化

摘要

以海南岛霸王岭刀耕火种和吊罗山择伐恢复的次生林为研究对象，设置幼龄林、中龄林和老龄林样地，研究凋落物及不同土层的最大持水率和自然含水率随干扰类型及恢复阶段的变化规律。结果显示，（1）刀耕火种凋落物和土壤的最大持水率及自然持水率都小于择伐；（2）两种干扰类型的凋落物最大持水率随着森林恢复而减小，自然含水率在3个恢复阶段间无显著差异。刀耕火种土壤的最大持水率随着森林恢复而增大。择伐0～40 cm土层最大持水率先减小后增大，40～60 cm土壤最大持水率在3个恢复阶段间无显著差异；（3）两种干扰类型的凋落物最大持水率和自然含水率都显著大于土壤；总体上，浅层土壤的最大持水率大于深层土壤，但不同土层间自然含水率无显著差异。（4）两种干扰类型中，凋落物与不同土层间的最大持水率显著负相关，二者间的自然持水率相关不显著。刀耕火种不同深度土壤间的最大持水率显著正相关；择伐不同深度土壤间的最大持水率及自然持水率都显著正相关。研究结果将为中国热带次生林生态恢复提供参考。%To assess the variation in the maximum water-holding ratio and nature-water-content rate of litter and soil in different depths during forest restoration process after shifting cultivation and selective logging, young-aged, middle-aged and old-growth forest plots were established in the secondary forest of Bangwangling and Diaoluoshan of Hainan island.The results showed that, (1) the maximum water-holding ratio and nature-water-content rate of litter and soil after shifting cultivation were lower than those of selecting logging; (2) the maximum water-holding ratio of litter decreased after disturbance , but nature-water-content rate did not differ among the three restoration stages.The maximum water-holding ratio of soil increased.However, the maximum water-holding ratio of 0~40 cm soil decreased and then increased after selecting logging .But it did not differ at the depth of 40~60 cm among the threerestoration stages; (3) the maximum water-holding ratio and nature-water-content rate of litter were grea-ter than those of soil.In general, the maximum water-holding ratio were higher than those of deeper soil, but the nature-water-content rate of soil in different depths did not differ; (4) for the two disturbance regimes, the maxi-mum water-holding ratio of litter was negatively correlated with those of soil in different depths .The nature-water-content rate, however, did not have significant correlation.The maximum water-holding ratio of soil in different depths of shifting cultivation were significantly correlated; the maximum water-holding ratio and nature-water-con-tent rate of soil in different depths were positively correlated with each others.