蒙古冰草(Agropyron mongolicum var.mongolicum)构件生物量分配特征对土壤类型的响应

Response of module biomass allocation of Agropyron mongolicum var.mongolicum to soil types

植物通过调节各器官的生物量分配来适应环境变化,生物量分配特征表征了各构件之间的功能权衡和植物的生长策略。本研究通过对比分析不同类型土壤中蒙古冰草(Agropyron mongolicum var.mongolicum)各构件生物量、构件分配格局及其相关关系,探讨蒙古冰草的生存策略。结果表明:在灰钙土、黑垆土和风沙土中,蒙古冰草各构件生物量分配均表现为茎>根>叶>穗,构件生物量分配模式均表现为贮藏分配>营养分配>繁殖分配,构件生物量分配模式本身与土壤类型无关。蒙古冰草对不同类型土壤的生长适应机制不同,风沙土中营养分配显著低于灰钙土和黑垆土,而贮藏分配则显著高于后两者,风沙土和黑垆土中繁殖分配比例则显著高于灰钙土。土壤pH和电导率是影响蒙古冰草根冠比、贮藏构件/营养构件、繁殖构件/营养构件和繁殖构件/贮藏构件生物量比例的主要因素;速效钾含量、pH和电导率是影响蒙古冰草叶/茎、叶/根、叶/穗、根/穗、根/茎和茎/穗生物量比例的主要因素。各构件生物量间以及构件生物量与株高间主要表现为异速生长关系,异速生长关系在不同土壤类型间存在差异。

Plants respond to and adapt to environmental changes by adjusting biomass allocation of various organs.Biomass allocation represents plant growth strategies and the functional trade-offs between components.In this study,biomass and allocation characteristics of each component in different types of soils were compared and analyzed,as well as allometric relationship,to explore the survival strategy of Agropyron mongolicum var.mongolicum.The results showed that there were significant differences in the biomass of each component among sierozem soils,dark loessial soils and aeolian soils,which showed stem>root>leaf>inflorescence;and the biomass allocation pattern of components was similar,which showed storage module>vegetation module>reproductive module.Different soil types had no significant effect on the total biomass,but significantly affected the biomass allocation ratio of most module biomass,such as,stem,root,inflorescence,vegetation,storage and reproductive module of A.mongolicum var.mongolicum.The vegetation module of A.mongolicum var.mongolicum in aeolian soils was significantly lower than that in indark loessial soils and sierozem soils,while the storage module was significantly higher than that in dark loessial soils and sierozem soils.The reproductive module ratio of dark loessial soils and aeolian soils were significantly higher than that of sierozem soils.Soil pH and electrical conductivity were the main factors affecting root-shoot ratio,biomass ratio of storage/vegetation,reproductive/vegetation and reproductive/storage of A.mongolicum var.mongolicum;available potassium,pH and electrical conductivity were the main factors affecting the biomass ratio of leaf/stem,leaf/root,leaf/inflorescence,root/inflorescence,root/stem and stem/inflorescence.The relationship among module biomass or between plant height and module biomass are mainly characterized by allometric relationship which was different among different soil types.