摘要
荒漠植物构型是植物与环境相互作用、相互适应的结果,其与功能的相互作用决定了荒漠植被的发展与演替。系统研究了半日花（Helianthemum songaricum）的分枝率、分枝角度、分枝长度和枝茎比等构型特征,对比研究了不同土壤类型和不同坡位间、半日花的构型特征响应及其适应机理。结果表明：覆沙地半日花的总体分枝率为0.49±0.03,石砾地半日花总体分枝率0.56±0.03;逐步分枝率SBR2：3和SBR3：4呈现覆沙地半日花大于石砾地半日花,SBR1：2则表现相反;半日花1~4级分枝角度集中在30°~42°,并且1级到4级呈增大趋势;覆沙地的枝茎比RBD2：1、RBD3：2、RBD4：3分别为0.57±0.05、0.59±0.05、0.51±0.05,石砾地分别为0.68±0.06、0.72±0.06、0.50±0.03,其中枝茎比RBD2：1、RBD3：2、RBD4：3都呈现先增大后减小趋势;覆沙地半日花的1~3级枝长均大于石砾地半日花,4级枝长小于石砾地半日花,且覆沙地和石砾地半日花的1~4级分枝长度呈依次减小的趋势;同一土壤条件下,不同坡位半日花的枝系构型特征不存在显著性差异。覆沙地半日花枝系长度、粗度、以及枝条数均大于石砾地半日花,能够获得更多空间资源,在植物竞争和演替过程中,其构型特征具有一定的优势。
Architecture characteristics of desert plants are final product of plant-environment interaction and mutual adaption,and the interaction and feedback among them would determine the development and succession of desert plant.In order to understand architecture characteristics and adaptation mechanism of Helianthemum songaricumin different soil types and different slope positions,the architecture characteristics including the bifurcation ratio,the branch angle,the branch length,and the ratio of branch diameter of H.songaricum were studied.The results showed that,the over bifurcation ratio of H.songaricumin sandy soil was0.49±0.03,lower than that of 0.56±0.03 in rocky soil;The stepwise bifurcation ratios of SBR2：3and SBR3：4of H.songaricumin sandy soil were less than those in rocky soil,while that of SBR1：2greater for H.songaricumin sandy soil relative to rocky soil;The branch angles of H.songaricum mainly ranged from30°and 42°,and tended to increase from the first class to the fourth class.The ratio of branch diameter RBD2：1,RBD3：2and RBD4：3of H.songaricum,increased first and then decreased with the value of 0.57±0.05,0.59±0.05 and 0.51±0.05 under sandy soil respectively,and 0.68±0.06,0.72±0.06,0.50±0.03 under rocky soil.The branch length of H.songaricumranged from the first class to the third class in sandy soil was greater than that in rocky soil,while the fourth class branch length was less in sandy soil than in rocky soil.And from the first class to the fourth class,the branch length decreased gradually in both soil types.In conclusion,the numbers,length and stem size of H.songaricum branch were greater in sandy soil than in rocky soil,so H.songaricumindividual in sandy soil can obtain more resource due to advantage of architecture characteristics in the process of vegetation competition and succession.
出处
《中国沙漠》
CSCD
北大核心
2016年第3期651-658,共8页
Journal of Desert Research
基金
国家科技计划项目专题(2012BAD16B0102)
国家自然科学基金项目(31470622)
