武夷山不同海拔毛竹细根功能性状

细根作为植物最重要的资源获取功能器官，是影响陆地生态系统的重要组成部分。定量化毛竹的细根功能性状对于理解其生理生态特征响应及生活史策略至关重要。为揭示毛竹细根功能性状随海拔梯度的变化规律以及细根的适应策略，对武夷山不同海拔(840 m、1040 m、1240 m)毛竹细根的碳(C)、氮(N)、磷(P)含量和比根长(SRL)、比根面积(SRA)等性状进行测定，分析细根性状在海拔上的差异及其异速生长关系。结果表明：(1)不同海拔毛竹细根养分性状存在显著差异。毛竹细根C含量在海拔1040 m最大。随海拔升高，细根N、P含量均呈下降趋势，细根C∶N、C∶P随着海拔的升高而增加。(2)细根的结构性状在海拔梯度上差异显著。随海拔升高，细根平均根直径(AvgDiam)、SRL及SRA均呈下降趋势，而根组织密度(RTD)呈升高趋势。(3)细根性状间存在显著的异速生长关系。细根N与P含量存在显著的等速生长关系，二者与C含量存在显著异速生长关系；SRL与SRA存在显著的等速生长关系，二者与RTD存在显著的负等速生长关系，与N含量存在显著的异速生长关系；细根AvgDiam与RTD存在显著的负异速生长关系。毛...

Fine root traits of Phyllostachys edulis at different altitudes in Wuyi Mountain

As the most important resource-obtaining functional organ of plants, fine roots are an important part affecting terrestrial ecosystems. Quantifying the fine root functional traits of Phyllostachys edulis is critical to our understanding of the physiological response and ecological characteristics for bamboo''s life-history strategies. To investigate the variation of fine root traits of Phyllostachys edulis with altitude gradient and the adaptation strategies of fine roots, the contents of carbon (C), nitrogen (N), phosphorus (P), specific root length (SRL), specific root area (SRA) and other traits of Ph.edulis''s fine roots were measured in Wuyi Mountain at different altitudes (840 m, 1040 m, 1240 m), and the differences of fine root traits at different altitudes and the allometric relationship between them were analyzed. The results showed that:(1) there were significant differences in the contents of C, N, P and the ecological stoichiometry among different altitudes. The content of C in fine roots was the highest at the altitude of 1040 m, with the increase in altitude, the content of N and P decreased, leading to the increase of the ratio of C:N and C:P. (2) There were significant differences on the structural traits of fine roots among different altitudes. As the altitude increased, the average root diameter (AvgDiam), SRL, SRA of fine roots all showed a downward trend, while the root tissue density (RTD) showed an upward trend. (3) There was a significant allometric relationship between fine root traits. The significant isometric relationships were found between N and P content in fine roots, but they showed a significant allometric relationship between C content. There was a significant isometric relationship between SRL and SRA, but they showed a significantly negative isometric relationship with RTD, and showed a significant allometric relationship with N content. The significantly negative allometric relationships were found between AvgDiam and RTD. There was a significant difference of fine root functional traits among different altitudes, and a significant allometric relationship between them. Our research showed that there was a trade-off between fine root acquisitive traits (such as SRL) and conservative traits (such as RTD). Ph.edulis tended to increase root length for increasing nutrient absorption at altitude of 840 m, and adopted the conservative strategy (such as increasing root tissue density) with increasing altitude. Therefore, Ph.edulis can rationally balance resource allocation among fine root traits to adapt to environmental changes through phenotypic plasticity mechanism.