太白红杉群落优势种的生态位研究

Studies on niche of dominant species in Larix chinensis communities

应用Levins和Shannon-Wiener生态位宽度指数及Pianka生态位重叠指数,研究了太白红杉群落12个优势种的生态位宽度和生态位重叠.结果表明,乔木层中太白红杉的生态位宽度最大,对高海拔地区的环境适应能力较强,巴山冷杉对的低海拔地区的环境适应能力较强;灌木层中香柏的生态位宽度最大,华西忍冬、华西银腊梅、太白忍冬次之,头花杜鹃的生态位宽度最小.乔木层中太白红杉与巴山冷杉的生态位重叠较大,但二者只在低海拔分布范围有重叠;灌木层头花杜鹃的分布范围较大,与其它3个种的生态位重叠也最大,另外3个种的生态位重叠较小;草本层中毛状苔草、羊茅和嵩草的生态位重叠较大,而大叶碎米荠和太白银莲花的生态位重叠较小.

In this paper,the niche breadth and niche overlay of 12 dominant species were studied,using the methods of Levins and ShannonWiener indexes of niche breadth and Pianka index of niche overlap.The result shows that the niche breadth of Larix chinensis is broadest in tree layer and the adaptation of Larix chinensis is strongest in higher altitude while Abies fargesii is in lower altitude.In shrub layer,the niche breadth of Sabina squamata var.wilsonii is broader than other 3 species.The niche overlay of Larix chinensis and Abies fargesii in tree layer is much large,but they formed mixed forest only in lower altitude.And the niche overlay of Rhododendron capitatum in shrub layer is largest.In grass layer,the overlay of Festuca graminifolia?Kobresia graminifolia and Carex capilliformis are larger than Cardamine macrophylla and Anemone taipaiensis.