基于功能性状探究富营养化对水生植物生长-繁殖权衡关系及其群落构建的影响机制

Functional traits for plants refer to a series of core properties closely related with growth, survival and reproduction, which usually have very important ecological significance. The functional trait-based studies have scaled from individual to ecosystems and rapidly expanded to many areas of ecological research. The study of functional traits in terrestrial forest mainly focuses on leaf, height and seed (LHS) while for herbaceous plant, propagules and clonal growth traits could play a more important role. Adapted from the water environment, aquatic plants has evolved special traits for the growth and reproduction. The study targets on the functional traits of submerged macrophytes in mid-low reaches of Yangzte River, focuses on the responses of the growth and reproduction trade-offs for submerged macrophytes to eutrophication, synchronously analyzes the functional traits of above/underground part of plants, compares the temporal changes of the growth of submerged macrophyte and functional traits related with reproduction during the different phase of life history, investigates the growth and reproduction trade-off and community assembly theory of submerged macrophytes based on functional traits, clarifies the community fluctuation, succession and decaying of submerged macrophyte during the process of eutrophication, provides theoretical methodological support for community reestablishment of submerged macrophyte in eutrophic lakes and the macrophyte management in clear-water lakes.

植物的功能性状是指植物体具有的与生长、存活和繁殖紧密相关的一系列核心植物属性, 这些性状通常有非常重要的生态学意义。基于植物功能性状的研究已经涵盖从个体到生态系统等多个生态学层次，并快速扩展到生态学研究的众多领域。陆生森林的功能性状研究常以叶片、株高、种子作为研究核心，而对于草本植物来说，繁殖体库和克隆生长这类功能性状可能更为重要。水生植物由于所处水环境的理化特性演化出独特的生长和繁殖特征。本项目以长江流域沉水植物的功能性状为对象，以生长-繁殖的权衡关系对湖泊富营养化的响应过程为核心，同步开展地上与地下植物功能性状的分析研究，综合比较不同生活史阶段水生植物生长与繁殖功能性状的时间变化过程，探讨以功能性状为核心的沉水植物生长-繁殖权衡关系和群落构建理论，阐述湖泊富营养化进程中水生植物群落波动、演替及消亡的过程，为富营养化湖泊沉水植群落的恢复重建、清水稳态湖泊水生植被的管理提供理论与方法支撑.

植物的功能性状是指植物体具有的与生长、存活和繁殖紧密相关的一系列核心植物属性，具有十分重要的生态学意义。本项目以长江流域沉水植物的功能性状为对象，开展了水生植物功能性状的环境关系解析，发现常见沉水植物的最大量子荧光效率存在中午抑制现象，揭示了水位波动对植物株高性状的影响。通过受控实验,以苦草和菹草为典型物种分析了不同营养状态（碳、氮、磷）下水生植物生长-繁殖功能性状权衡关系的响应，同时还以三种不同生长型的六种植物为对象了分析了沉水植物随着水体营养水平的增加，生物量分配的规律及生长与繁殖性状间的差异。研究结果表明无机碳水平可以显著影响沉水植物的有性繁殖并与有性-无性繁殖产生复杂的交互作用；高氮磷营养水平可以直接影响沉水植物的生物量分配及生长与繁殖的权衡。因此，本研究有助于阐明湖泊富营养化进程中水生植物群落波动、演替及消亡的过程。