为了解木麻黄在生长发育过程中对环境胁迫的适应性及其适应策略,开展其不同发育阶段植冠的枝系特征分析,并以此为中国沿海防护林建设提供一定的理论指导,通过对福建省大鹤国有防护林场不同生长发育阶段的木麻黄的枝系特征进行统计分析。结果表明:木麻黄在不同发育阶段的总体分枝率和逐步分枝率SBR1:2无显著变化,但逐步分枝率SBR2:3在成株阶段与幼树阶段表现出显著差异;幼苗阶段的1级枝倾角及2级枝倾角与成株阶段及幼树阶段均表现出显著差异;通过对各种枝系特征分析,发现成株阶段高生长不明显,受风力胁迫影响,枝系水平向下生长;幼苗阶段表现出高生长,为获得充足的阳光进行光合作用而向上生长,其1级枝倾角及2级枝倾角总体表现出水平向上的趋势;在幼树阶段,同样表现出枝系水平向下生长的趋势。小枝的枝长、枝宽在幼苗、幼树到成株阶段表现出无明显的规律性,小枝节间数从幼苗、幼树到成株阶段表现出逐渐减少的趋势。
In order to understand the adaptive response of C. equisetifolia L. to environmental stress and its adaptive strategy in different growth and developmental phases, architectural characteristics of C. equisetifolia L. were analyzed to provide theoretical guidance for coastal protection forest construction of China. In Dahe state-owned forest farm, Fujian Province, the branching patterns of C. equisetifolia L. in different growth and developmental phases were examined. The results showed that overall bifurcation ratio and stepwise bifurcation (SBR1:2) didn' t vary significantly among different phases, but the stepwise bifurcation (SBR2:3) in sapling phase was significantly lower than that in the mature phase (P〈0.05). The first order branch angle to horizon and the second order branch angle to horizon in seedling stage were significantly different with the mature and the sapling stages. In different development stages, the architectural comparison showed that: in mature tree stage, forced by the wind, tree' s growth slowed down and the branching of C. equisetifolia L. grew downward relative to the horizontal plane. In seedling stage, tree' s heigtlt grew rapidly to obtain enough sunlight for photosynthesis, so the first order branch angle to horizon and the second order branch angle to horizon of it performed the trend of upward relative to the horizontal plane. In sapling stage, the branching of C. equisetifolia. L also performed the trend of downward relative to the horizontal plane. The length and width of branehlet showed no obvious regularity in seedling, sapling and mature stages. The interval of hranchlet performed the trend of decreasing gradually from seedling, sapling to mature stages.