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环境异质性可以影响克隆水生植物的表现.鲜有研究者关注两个层次的环境异质性并将其融入对克隆植物生态学的研究中.本研究的目的是:(1)检验不同基质异质性与水淹处理是否对植物表现产生相似效应,(2)探索克隆植物的觅食行为.本研究将荆三棱(Scirpus yagara)置于不同基质异质性与水淹处理之中.基质处理包括1个均质性基质处理(湖泥与沙等体积混合)与3个异质性基质处理(湖泥斑块与沙斑块交错构建的两斑块、四斑块与八斑块基质).水淹处理包括:0、10和30 cm.本实验测量了克隆分株数、克隆代数、叶数、球茎数、克隆分株高度、茎长、根状茎长、克隆半径、间隔子长、间隔子厚度、总生物量、球茎生物量与单个球茎生物量等性状数据.研究结果表明,水位上升导致克隆分株数、克隆代数、叶数和球茎数显著减少,同时基质异质性造成间隔子长度与间隔子厚度的显著变化.水位与基质异质性两因子对克隆分株数、叶数和间隔子长度产生了显著的交互效应.在两斑块基质与四斑块基质中,荆三棱对湖泥斑块表现出显著的觅食行为,更多的构件被放置于湖泥斑块中.尤其在两斑块基质中,所有的构件被放置于湖泥斑块中.在八斑块基质中,荆三棱表现出双向觅食,这导致构件在不同斑块中的均匀放置.研究结果表明,荆三棱的觅食行为与斑块大小具有相关性.“,”Aims Environmental heterogeneity affects the performance of clonal aquatic plants.Few researchers integrated two aspects of heterogeneity into the study of clonal plant ecology.The aims of the present study are to(i)test whether different substrate heterogeneity and submergence exert similar effects on plant performance and(ii)explore the foraging behaviour.Methods In this study,Scirpus yagara was subjected to multiple levels of substrate heterogeneity and submergence.Substrate treatments included one homogeneous substrate and three heterogeneous substrates(two-patch,four-patch and eight-patch).Water level treatments included 0,10 and 30 cm.Traits including ramet number,generation number,leaf number,bulb number,ramet height,culm length,rhizome length,clonal radius,spacer length,spacer thickness,total biomass,biomass of bulbs and biomass per bulb were measured.Important Findings Deeper water levels significantly reduced variables associated with growth such as ramet number,generation number,leaf number and bulb number,while substrate patchiness induced significant variations in traits such as spacer length and spacer thickness.Significant interactive effects of the two factors were found for ramet number,leaf number and spacer length.Scirpus yagara showed colonization towards the lake sediment patch in two-patch and four-patch substrates,and more structures were placed in the lake sediment patch.Especially for the two-patch substrate,all structures occupied the lake sediment patch.Two-sided intrusion was observed in the eight-patch substrate,which induced an even allocation of structures in different patches.The foraging behaviour was correlated with the patch size.