广佛地区典型湿地类型植物多样性与土壤因子的关系

Relationship Between Plant Diversity and Soil Factors of Typical Wetland Types in Guangfo Area

为了解土壤影响湿地植物多样性的主要因子,在广佛地区9大湿地类型选取18个样地为研究对象,运用方差分析、典范冗余分析(RDA)、典范对应分析(CCA)对群落分布、植物多样性与土壤因子间的相关性进行分析。结果表明,广佛地区有湿地植物312种,隶属90科198属,以禾本科(Gramineae)、莎草科(Cyperaceae)、菊科(Compositae)等为优势科。草本植物占绝对优势,占79.17%。主成分评价结果表明,近海及海岸湿地土壤养分水平较高。RDA排序分析结果表明土壤因子对植物多样性影响较大的指标是土壤有机质、全氮、全磷、全钾、碱解氮;CCA排序结果表明土壤环境因子对湿地草本植物群落分布主要影响因子为pH、速效钾、有效磷。因此,湿地生态系统比陆地生态系统更为复杂和脆弱,植物群落与土壤环境因子之间的关系也更为复杂,湿地植被的分布格局、群落多样性、群落结构和土壤条件及其相互关系受到人为干扰的类型和强度影响更加明显。

In order to understand the main factors of soil affecting wetland plant diversity,18 sample plots were selected from 9 wetland types in Guangfo area.The wetland community species composition,plant diversity and soil factors were studied through field work and laboratory experiment.Furthermore,the correlations among community distribution,plant diversity and soil factors were analyzed by variance,canonical redundancy analysis(RDA)and canonical correspondence analysis(CCA).The results showed that there were 312 wetland species,belonging to 90 families and 198 genera,with Gramineae,Cyperaceae and Compositae as the dominant families.In addition,herbs are the most abundant in wetland plants,accounting for 79.17%.The principal component analysis showed that the level of soil nutrients in offshore and coastal wetlands was high.Moreover,the RDA analysis showed that soil factors with a great impact on plant diversity were soil organic matter,total nitrogen,total phosphorus,total potassium and alkali hydrolyzable nitrogen.From CCA,the main influencing factors of soil environmental factors on wetland herb community distribution are pH,available potassiumand available phosphorus.In conclusion,wetland ecosystem was more complex and fragile than terrestrial ecosystem,and the relationship between plant community and soil environmental factors was also more complex.The species distribution pattern,community diversity,community structure,soil conditions and their relationship of wetland vegetation are more obviously affected by the human disturbance.