三种锦鸡儿属植物的克隆生长特性及其植被恢复意义

Growth characteristics and its vegetation restoration significant of clonal of three Caragana species

为了研究适于甘肃定西黄土丘陵沟壑区植被恢复的主要灌木种,以本地种白毛锦鸡儿(Caragana licentiana) 和甘蒙锦鸡儿(C．opulens)以及外来种中间锦鸡儿(C．intermedia)为对象,研究其克隆生长特性。白毛锦鸡儿和甘蒙锦鸡儿由根状茎产生很多无性系分株,均为松散游走型克隆生长构型,其根状茎错纵复杂,结成网状结构。在黄土丘陵沟壑区相对干旱的环境以及动物胁迫下,白毛锦鸡儿种子繁殖受到限制,无性繁殖有助于其种群的更新和扩展。白毛锦鸡儿的分株种群在半阳坡比在半阴坡有显著大的分株数、根状茎数、基株最大半径、根状茎长和根状茎生物量分配,反映出其形态的可塑性。游走型的克隆生长构型和根状茎的网络结构,赋予白毛锦鸡儿很好的水土保持性能。中间锦鸡儿为单轴型构型,在定西地区不产生无性系分株。

The native leguminous species, C. licentiana, C. opulens and C. intermedia, can produce many ramets by rhizome. They exhibited sympodia branching pattern and “guerilla” architecture and have strong ability to spread at horizontally. The persistent rhizomes formed closely crowed below ground networks for this native species. No ramets induced from root in C. intermedia. Authors suggested that vegetative expansion is a regeneration strategy for C. licentiana when seed germination and seedling establishment restricted by relative drought and animal predation. Compared with that in the north-facing sloping hill, the ramet population in the south-facing sloping hill of C. licentiana exhibited significantly more ramets and longer rhizome internode and greater biomass allocation to rhizome but similar ramet height, which show morphological plasticity for C. licentiana.