崇明东滩湿地芦苇种群内功能性状及生态对策变异分析

Analysis on Intra-population Variations of Functional Traits and Ecological Strategies of Phragmites australis in Chongming Dongtan Wetland Based on CSR and LHS System

摘要:

植物种群功能性状及生态对策变异对其自身环境适应能力及群落结构具有重要影响。该文基于崇明东滩湿地芦苇(Phragmites australis)种群内3个小种群不同发育时期分株集合的多项性状指标，分析了其性状及生态对策变异，并基于CSR、LHS生态对策体系，对各小种群的生态对策进行了排序。结果表明, 3个芦苇小种群的21项性状指标及C、R对策得分均存在显著差异。在LHS体系中，以比叶面积(11.5 mm²/mg)、株高(175 cm)和花序干质量(4 g)为分界线，可对3个小种群进行区分。处于生殖生长期的芦苇分株具有更大的植株大小、更高的叶片干物质含量及S对策得分，而处于营养生长期的分株则具有较小的植株大小、较大的比叶面积及R对策得分。总体而言，崇明东滩湿地3个芦苇小种群间及各小种群内处于不同生长发育阶段的分株集合间，都存在显著的性状差异及生态对策差异，且二者的差异模式基本吻合。芦苇种内性状及生态对策变异特征，可为该区芦苇种群的生态保育和恢复实践提供重要的理论参考和技术支撑。

Abstract:

The variations of functional traits and ecological strategies of population may greatly affect its adaptive capacity and the structure of a community. Based on the multiple functional traits of the ramet groups at the different developmental stages of 3 subpopulations of Phragmites australis in Chongming Dongtan wetland, this paper analyzed its intra-population variations of functional traits and ecological strategies, and made an ordination of the ecological strategies of each subpopulation based on the CSR and LHS schemes. The results showed that 21 functional traits, C and R strategy scores among the 3 subpopulations of P. australis were significantly different. In the LHS scheme, 3 subpopulations were separated along the boundary line of the specific leaf area (11.5 mm²/mg), plant height (175 cm) and inflorescence dry weight (4 g). Ramets at the reproductive growth stage were characterized by larger plant sizes, higher leaf dry matter contents and S scores, while those at the vegetative growth stage, the smaller plant sizes, larger specific leaf areas and R scores. In general, there were significant differences in functional traits and ecological strategies among 3 subpopulations and between the ramet groups at the different developmental stages, and the divergent pattern of functional traits and ecological strategies were basically consistent. These might provide important theoretical reference and technical support for the ecological conservation and restoration of P. australis population in this area.