长江口北支湿地植物多样性研究

在对长江口北支湿地植物资源野外调查的基础上，分析了种子植物的物种组成、区系特征、湿地植物群落类型及其特征和典型湿地植物群落多样性。研究结果表明：长江口北支湿地分布有种子植物57科157属212种，其中裸子植物5科6属6种，被子植物52科151属206种（包括单子叶植物8科31属37种，双子叶植物44科120属169种），主要由草本植物组成。野生植物区系简单，植被演替还处在初级阶段，以湿生的和水生高等草本植物为主，世界广布和泛热带分布型占主导；菊科、禾本科、豆科为植物区系的骨干。海三棱蔗草群落、藤草群落、芦苇群落、大米草群落为该区四种典型湿地植物群落，群落的单纯度指数除芦苇群落的较低外，其他三种群落均很高，物种多样性指数、物种丰富度指数、均匀度指数除芦苇群落的较高外，其他三种群落均很低，验证了物种多样性与物种丰富度、均匀度呈正相关，与单纯度呈负相关的结论。

The Study on Plant Diversity of North Branch of Changjiang Estuary Wetland

Based on on-field investigation on North branch of Changjiang estuary wetland, the paper analyzed the species composition and flora characteristics of seed plants, wetland plant community types and their characteristics,and the typical wetland plant community diversity. It＇s indicated that North branch of Changjiang estuary has 57 species,157 genera and 212 families of seed plants.Among them there are 6 species,6 genera and 5 families in Pteridophyta,206 species,151 genera and 52 families in Gymnosperma（37 species,31 genera 8 families in Monocotyle doneae and 169 species, 120 genera, 44 families in Dicotyle doneae）.The seed plants are mainly made up of herbage plants. Wild flora is simple and at the stage of primary evolution.Most of them are hydrophytes and hygrophyte superior herbage plants. Cosmopolitan and pantropic distribution patterns are the main floristic elements. Composite,standing grain,legumina make up the backbone of floristic. Scripus mariqueler community, Scirpus triquerter community, Phragmites australis community and Spartina angilicare community are four typical wetland plant communities. Evenness index of Scripus mariqueler community, Scirpus triquerter community and Spartina angilicare community are all high except Phragmites australis community. Species diversity index, species richness diversity index, evenness index of Scripus mariqueler community, Scirpus triquerter community and Spartina angilicare community are all low except Phragmites australis community.It validated that positive correlation was observed among species diversity, species richness and evenness, negative correlation existed between species diversity and pureness.