| 摘要: |
| 本研究以长江上游消落带为研究区域,于退水恢复期采集狗牙根(Cynodon dactylon)与甜根子草(Saccharum spontaneum)的根、茎、叶及根际土壤样品,测定全碳(TC)、全氮(TN)、全磷(TP)含量及其化学计量比,揭示两种禾本科植物的差异化适应策略。结果表明：(1)狗牙根根部TC显著高于甜根子草,叶片TN、TP显著占优；甜根子草茎部TN、TP显著高于狗牙根,呈茎部优先的种间分异。(2)土壤呈“贫氮富磷”特征,TC和TN远低于全国均值,植被恢复期受强烈氮限制。(3)植物-土壤相关性显示,狗牙根根部养分与土壤特性高度相关；甜根子草茎部养分与土壤紧密关联,以构建高效转运通道。两种植物采取差异化策略：狗牙根为“保守型”资源分配策略,甜根子草为“获取型”资源分配策略。研究结果为消落带生态修复提供了科学依据。 |
| 关键词: 长江消落带 生态化学计量 狗牙根 甜根子草 养分分配策略 |
| DOI： |
| 投稿时间：2026-06-19修订日期：2026-08-03 |
| 基金项目:国家自然科学基金项目（面上项目，重点项目，重大项目）（32001390）；宜宾学院高层次人才“启航”计划项目（2024XJQH05） |
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| Analysis of Ecological Stoichiometric Characteristics of Two Typical Herbaceous Plants and Their Rhizosphere Soils in the Yangtze River Water-Level-Fluctuating Zone |
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LI Yunyi, ZAXi Danzhu, GUAN Shuangyan, GAO Gang, SHI Mingfu, SU Yongying, GUO Aixia
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| (Department of Agriculture,Forestry and Food Engineering,Yibin University,Yibin,Sichuan) |
| Abstract: |
| In this study, the roots, stems, leaves and rhizosphere soil samples of Cynodon dactylon and Saccharum spontaneum were collected during the recovery period after water withdrawal in the water-level-fluctuating zone of the upper reaches of the Yangtze River. The contents of total carbon (TC), total nitrogen (TN), total phosphorus (TP) and their stoichiometric ratio were determined to reveal the differential adaptation strategies of the two gramineous plants. The results showed that: (1) TC in the roots of Cynodon dactylon was significantly higher than that in the roots of Saccharum spontaneum, and TN and TP in the leaves were significantly dominant. The TN and TP in the stems of Saccharum spontaneum were significantly higher than those of Cynodon dactylon, showing the interspecific differentiation of stem priority. (2) The soil was characterized by “poor nitrogen and rich phosphorus” , TC and TN were far lower than the national average, and the vegetation recovery period was strongly limited by nitrogen. (3) The plant-soil correlation showed that the root nutrients of Cynodon dactylon were highly correlated with soil characteristics. The nutrients in the stems of Saccharum spontaneum are closely related to the soil, and an efficient transport channel is constructed. The two plants adopt a differentiated strategy: Cynodon dactylon is a “conservative” resource allocation strategy, and Saccharum spontaneum is a “acquisitive ” resource allocation strategy. The research results provide a scientific basis for the ecological restoration of the water-level-fluctuating zone. |
| Key words: Water-level-fluctuating zone Ecological stoichiometry Cynodon dactylon Saccharum spontaneum Nutrient allocation strategy |
