松嫩平原优势种羊草与其主要伴生种芦苇空间分布格局分析

芦苇是松嫩草地优势种羊草的主要伴生种,两者常常形成物种组成比较单一的混生群落或者与其他物种组成羊草 杂类草群落.选择羊草 芦苇混生群落,羊草群落和芦苇群落的交错区进行羊草、芦苇单物种格局分析.结果表明,1)混生群落和交错区中,羊草和芦苇均是以集聚分布的形式存在;2)羊草在混生群落中的格局强度小于交错区中的格局强度,芦苇在2种类型群落中的格局强度没有显著差异;3)除了考虑物种的生物学特性以外,混生群落种内、种间竞争也是影响羊草集聚分布和格局强度的主要因素,交错区中,环境异质性和种间竞争是影响集聚分布和格局强度的重要因子;4)芦苇在混生群落和交错区中格局强度没有明显差异,由此可以判定芦苇的空间分布格局形成主要受植物本身生物学特性的影响.

Analysis of spatial distribution pattern for Leymus chinensis and its co-existing specie--Phragmites communis in the Songnen Plains

The Songnen Plain is dominated by Leymus chinensis,which usually co-exists with Phragmites communis,to form either two or multi-specie communities.The patterns of L.chinensis and P.communis were studied in both the L.chinensis +P.communis communities and in the ecotones of the two-species communities.Results showed that 1) L.chinensis and P.communis were distributed in aggregates both in the mixed communities and in ecotones.2) Aggregative intensity of L.chinensis in the ecotone was larger than that in the mixed community,however no significant difference was found for P.communis.3) The distribution type and pattern intensity of L.chinensis were influenced by intraand inter-specific competition,in addition to biological characteristics.Soil heterogeneity and inter-specific competition were the most important factors for L.chinensis in ecotones.4) The species characteristic of P.communis was an important factor because there was no significant difference of aggregative intensity in the mixed communities and the ecotones.