滇西北亚高山草甸退化梯度上马蹄黄地上形态特征变化

马蹄黄(Spenceria ramalana)是滇西北亚高山草甸的旅游景观资源,其地上形态特征随草甸退化梯度的变化趋势尚少见报道。于2018年7月在香格里拉市调查、对比了3个退化梯度(一级退化,DI;二级退化,DII;无退化对照,CK)上马蹄黄的植株高度、展度、叶片数量、叶片长度、叶片宽度、叶面积、叶片长宽比和生存状态。结果表明:(1)与CK相比,DI和DII梯度上马蹄黄的植株高度、展度、叶片数量、叶片长度、叶片宽度和叶面积均显著减小(P<0.05);(2)DII梯度上马蹄黄的叶片长度、叶片宽度和叶面积显著高于DI梯度(P<0.05);(3)CK、DI和DII中马蹄黄的叶片长宽比分别为3.5±0.3、2.9±0.4和2.3±0.1,叶片形状由倒披针形向倒卵形过渡;(4)DI、DII和CK中马蹄黄的生存状态指数分别是0.12、0.23和0.63。

CHANGES OF ABOVEGROUND TRAITS OF SPENCERIA RAMALANA ALONG A DEGRADATION GRADIENT OF A SUBALPINE MEADOW IN NORTHWEST OF YUNNAN PROVINCE

Spenceria ramalana,which lives in subalpine meadows and blooms yellow flowers,is a kind of resource for tourist in northwest of Yunnan Province.However,there is limited knowledge about the changes of aboveground traits of S.ramalana along the land degradation gradient.To explore the changes of aboveground traits of S.ramalana(i.e.,the height,lateral spreading of individual,number of leaves,leaf length,leaf width,leaf area,length/width ratio of leaf and individual living state)a filed survey was conducted in July,2017.This filed survey covered three levels of land degradation,i.e.,the control treatment(CK),the seriously degraded treatment(DI)and the moderately degraded treatment(DII).We found that:1)the plant height,lateral spreading of individual,number of leaves,leaf length,leaf width and leaf area in the treatments of DI and DII were significantly lower than them in the treatment of CK(P<0.05).2)The leaf length,leaf width and leaf area in the treatment of DII were significantly higher than them in the treatment of DI(P<0.05).3)The leaf’s length/width ratio of CK,DI and DII treatments was 3.5±0.3、2.9±0.4 and 2.3±0.1,respectively,which means the shape of the leaf shifted from an oblanceolate one to an obovate one along the degradation gradient.And 4)the living state index of DI,DII and CK was 0.12,0.23 and 0.63,respectively.