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对神农架不同海拔杜鹃种群进行了调查,并对高海拔地带杜鹃群落特征进行了分析。杜鹃在中海拔1 400.00~2 200.00 m范围内物种数最多,呈“单峰”分布。高海拔杜鹃群落木本植物多样性随海拔升高而明显降低,草本植物多样性则变化不大,杜鹃随着海拔的升高而优势度升高。各样方中物种丰富度比较的结果是,草本层>灌木层>乔木层。树木自然枯死现象较为普遍,平均有枯木19棵,平均胸高直径之和为149,枯木平均胸高直径为9.10 cm。更新层的杜鹃平均盖度16.00%,均高1.48 cm。更新层的巴山冷杉平均盖度为1.30%,均高为1.43 m。具分支干的杜鹃基干数量占所有基干的13.90%,但其支干数占到总(支)干数的30.50%。大量丛生现象使杜鹃形成紧密的群丛。10个样地中乔木层的巴山冷杉平均胸径为13.70cm,冷杉的恢复状况良好。
Investigations were made on the populations of Rhododendron at different altitudes in Shennongjia and the characteristics of Rhododendron community in high altitude were analyzed. Rhododendron had the highest number of species in the range of 1 400.00 ~ 2 200.00 m in mid-elevation, which was distributed as “unimodal”. The diversity of Rhododendron community at high altitude significantly decreased with the elevation, and the diversity of herbaceous plants changed little. The Rhododendron increased with the elevation increasing. As a result of comparison of species richness in various plots, herb layer> shrub layer> arbor layer. The phenomenon of natural dead trees are more common, with an average of 19 dead wood, the average diameter of the chest height of 149, dead wood average diameter of 9.10 cm. The average coverage of rhododendrons in the regeneration layer was 16.00%, both high 1.48 cm. The average coverage of Bashan fir in the updated layer was 1.30% with an average height of 1.43 m. Branches of rhododendrons accounted for 13.90% of the total stems, but the number of branches accounted for 30.50% of the total (branches). A large number of clusters of rhododendron to form a close cluster. In the 10 plots, the mean DBH of the tree layer of Bashan fir was 13.70 cm, and the recovery of fir was good.