遮阴对大头茶、薄果猴欢喜幼苗生长的影响

对２ａ生大头茶（Ｇｏｒｄｏｎｉａａｃｕｍｅｎａｔａ）和薄果猴欢喜（Ｓｌｏａｎｅａｌｅｐｔｏｃａｒｐａ）幼苗进行遮阴实验，结果表明，大头茶幼苗的叶面积、茎长、枝长年变化曲线和总生量为：全光照＞部分光照＞部分阴暗＞阴暗；而薄果猴欢喜为：部分阴暗＞阴暗＞部分光照或全光照，这体现了阳性树种（大头茶幼苗）和阴性树种（薄果猴欢喜幼苗）的不同特点。从全光照到阴暗，大头茶、薄果猴欢喜幼苗的平均叶面积重（ＳＬＷ）和根／冠比均下降，而叶面积率（ＬＡＲ）均增加，并且，平均叶面积在部分阴暗下最高，全光照下最低。可见，大头茶、薄果猴欢喜幼苗对其相应光环境具有一定的适应能力

Effects of Shading on Growth of Gordonia acumenata and Sloanea leptocarpa Seedlings

Two-year old seedlings of Gordonia acumenata and Sloanea leptocarpa were used to investigate their growth influenced by shading. The results showed as follows: The total biomass and annual change curves of leaf area, stems and branches of G. acumenata seedlings were full sun, partial sun, partial shade and shade from top to bottom respectively, but those of S. leptocarpa seedlings were partial shade, shade, partial sun or full sun, which coincided with the characteristics of light-demanding tree species (G. acumenata) and of shade-tolerant tree species (S. leptocarpa); Both the mean specific leaf weight (SLW) and the value of root/shoot ratio of the two species seedlings decreased with the light-intensities from full sun to shade, but their leaf area ratio(LAR) increased and the mean leaf area was greatest in partial sun, lowest in shade, which indicated that the two species seedlings had been improved to adapt to their corresponding light environments.