崩尖子自然保护区锐齿槲栎林种群结构与生活型谱垂直分布规律研究

Population structure and life form spectrum of Quercus forest along elevation gradients in Bengjianzi Natural Reserve

研究湖北省长阳县崩尖子自然保护区锐齿槲栎林的种群结构和生活型谱以及与海拔高度之间的关系.结果显示：锐齿槲栎林在研究区主要分布于海拔1 400~1 800 m处,群落结构相对简单;随着海拔升高,锐齿槲栎胸径逐步增加,低海拔地区以小径级（DBH≤10 cm）个体居多,随海拔升高大径级（DBH〉20 cm）树木比例增加;沿海拔梯度,锐齿槲栎的平均树高和平均胸径都呈现出逐步增大的趋势;最大胸径值起伏较大,发展趋势不甚明显;植物生活型组成以高位芽植物为主,其次是地面芽和地上芽植物,1年生植物较少,未统计到隐芽植物;不同海拔的植物生活型谱有所不同,较低海拔地段Raunkiaer生活型谱呈＂U＂形,其他3个高海拔样地大致呈＂L＂形.

Variations in population structure and plant life- form spectrum of Quercus forest along analtitudinal gradient were investigated in Bengjianzi natural reserve. Quercus forest is mainly composed ofQuercus aliena var. acuteserrata. The results were as follows： Quercus forest is mainly distributed between thealtitude of 1400 1800 m in this area,and the community structure is relatively simple;At low altitude,Quercus trees of a DBH less than 10 cm were dominant. With increasing altitude,the proportions of trees withlarger DBH（20 cm） increased gradually. There is a gradual increasing trend of average height and averagediameter along the altitudinal gradient. However,the maximum diameter value fluctuated a lot,with noobvious trend;The life- form spectrum is composed largely of Phanerophytes. Hemicryptophytes andChamaephytes take the second place. There are relatively few Therophytes and not Cryptophytes were everfound;The plant life-form spectra are different in different altitudes. Raunkiaer life form spectrum shows a ＂U＂ shape in the lower elevation sites,and ＂L＂ shape at the other three high altitudes.