林隙对林下主要植物叶性状与光合特性的影响1）--以西藏急尖长苞冷杉林为例

摘要

在3个典型林隙下选择林下灌木（杯萼忍冬、峨眉蔷薇、薄毛海绵杜鹃）和急尖长苞冷杉个体，研究林隙对4种植物叶性状与光合特性的影响。结果表明：随着林隙面积增加，杯萼忍冬叶性状无明显变化，但光合潜力和暗呼吸速率分别升高了75％和186％；峨眉蔷薇和薄毛海绵杜鹃叶片叶绿素质量分数、比叶重和光合潜力均增加，而暗呼吸速率降低了138％；急尖长苞冷杉幼苗叶绿素质量分数、比叶重和暗呼吸速率均升高，且光合潜力下降。这说明林隙大小对杯萼忍冬基本无影响；峨眉蔷薇和薄毛海绵杜鹃在大面积的林隙下生长更好，而急尖长苞冷杉幼树则仅适宜在小面积的林隙下生长。%We chose three shrub species and Abies georgei var.smithi saplings to study the effect of three typical forest gaps on leaf morphological and photosynthetic characteristics of main species in A.georgei var.smithi forest.The different size of forest gaps has no effect on leaf morphology of Lonicera inconspicua, but Pn max and Rd increased by 75%and 186%, re-spectively.Chlorophyll relative content, specific leaf weight and Pn max of Rosa omeiensis and R.aganniphum var.schizo-peplum increased from small gap to big one, with Rd reducing by 138%.Otherwise, there is an opposite trendy of Rhodo-dendron aganniphum var.schizopeplum with the same index of R.omeiensis.Big gap shows a positive effect on increasing chlorophyll relative content, specific leaf weight and Rd, although its Pn max reduces.Therefore, the size of forest gap has no significant effect on L.inconspicua.R.omeiensis and R.aganniphum var.schizopeplum grow better in the bigger size of forest gaps, and the small ones are suitable for A.georgei var.smithi survival.