三江平原小叶章构件种群结构特征对水分的生态适应

Ecological adaptability of structural characteristics of Deyeuxia angustifolia component population to water conditions in the Sanjiang Plains of China

小叶章是根茎型无性系禾本科植物,具有广泛的生态适应性。本文选择典型草甸、沼泽化草甸、沼泽三个具有代表性的小叶章群落。通过对3个生境在生长季内小叶章构件种群的调查和测定,对小叶章构件种群的生态适应性和生长规律进行了统计分析。结果表明:不同生境的小叶章构件种群在表型性状上都有不同程度的变异。其中,沼泽小叶章的形态变异最大,沼泽化草甸小叶章的变异最小,形态特征相对恒定。在生境内,各表型性状都存在着丰富的变异,但变异的程度不同,其中变异程度最大的是侧叶数,叶长在沼泽和沼泽化草甸小叶章中的变异程度最小,株高在典型草甸小叶章中的变异程度最小。不同生境小叶章种群各特征的空间动态变化各不相同,受环境影响较大。3种生境小叶章种群分株数量性状在5月份均呈现生境内大于生境间,除沼泽小叶章外,6月和9月的生长期里大体呈现生境内大于生境间;而7月份恰恰相反基本表现为生境内小于生境间,除典型草甸小叶章外,8月份的生长期里大体呈现生境内小于生境间。在生长季内,3种生境小叶章分株各层的叶绿素含量均在6月份达到最大值;典型草甸、沼泽化草甸小叶章分株各层的叶面积均在7月份达到最大值;而沼泽小叶章分株各层的叶面积在8月份达到最大值。

Deyeuxia angustifolia,which is a typical clonal plant of grass family with rhizome,has a broad ecological adaptation.This paper selected the representative communities of Deyeuxia angustifolia in the typical meadow,marsh meadow,mash.This experiment on Deyeuxia angustifolia population was conducted on three habitats in growth season and the ecological plasticity of ramets module was analyzed statistically.The results indicated： The phenotypic characters of Deyeuxia angustifolia population showed abundant variations in different habitats.Further,morphological differences reached maximum values in the mash,but minimum values in the marsh meadow.Morphological characters kept stable comparatively.Within habitats,phenotypic characters showed abundant variations.The side leaf numbers reached maximum variation.The leaf length reached minimum variation in the marsh meadow and mash.Height reached minimum variation in the typical meadow.There were some differences in the spatial dynamic change on Deyeuxia angustifolia population characters in different habitats and the characteristics were mostly influenced by the environment.The quantitative characters of Deyeuxia angustifolia population in three habitats were larger variations within habitats than among habitats in May,apart from the mash.There were larger variations within habitats than among habitats in June and September,but smaller variations in August.There were smaller variations within habitats than among habitats in July,apart from the typical meadow.In growth season,the different levels chlorophyll of Deyeuxia angustifolia ramet reached maximum values in June in three habitats.The typical meadow and marsh meadow reached maximum values in July.The mash reached maximum values in August.