山西浊漳河北源湿地草本植物群落优势种生态位与种间关系

以山西浊漳河北源湿地草本植物群落调查为基础,通过生态位指数测度、方差比率法、χ2检验、联结系数AC、Pearson相关系数检验对16个优势种群进行了生态位和种间关联的分析。结果表明,1)藨草(Scirpus triqueter)、头穗莎草(Cyperus glomeratus)、水蓼(Polygonum hydropiper)的生态位宽度值相对较大,在研究区域内具有泛化种倾向;2)120个种对间的生态位重叠指数低,55%的种对之间不存在重叠,种间竞争弱;3)群落内植物整体关联度为显著负相关(P0.05),χ2检验与Pearson相关系数检验的正负关联比(分别为0.52和0.15)均小于1,负关联的种对数多于正关联,且大多数种间关联程度不显著(P0.05),说明浊漳河北源湿地草本植物群落结构简单,物种间相互作用较弱,处于演替初期阶段;4)物种间的生态位重叠指数与联结系数AC、Pearson相关系数存在着显著的正相关关系(P0.05),且Pearson相关系数的拟合效果优于AC联结系数。本研究有利于更好地认识优势种种间的相互关系及群落的动态特征,了解浊漳河北源湿地利用现状,为湿地生态恢复提供理论依据。

Niche and interspecific associations for dominant species in wetland herb communities in the northern branch of the Zhuozhang River Watershed,Shanxi

Based on sample investigations of wetland herb communities in the northern branch of the Zhuozhang River Watershed,we analyzed interspecies relationships and niche characteristics for 16 main species.Important findings were as follows:1) Scirpus triqueter,Polygonum hydropiper,and Cyperus glomeratus showed tendencies of generalized species such as the largest niche breadth among dominant species;2) a niche overlap of 55％ was observed in 0 of 120 species pairs,and lower niche overlap between species indicated weaker interspecific competition;3) Overall association of phytocoenosium was significantly negative correlation at the 0.05 level,the ratios of positive and negative associations in x2-tests and Pearson correlation coefficients were 0.52 and 0.15;therefore,the negative associations were more than the positive associations,and most interspecific associations were not significant,suggesting that wetland herb communities structure is simple,the interaction between species is weak,the communities are still under dynamic succession;4) both association coefficients (AC)and Pearson correlation coefficients indicated niche overlap,with the fitting effect of Pearson correlation coefficient showing a stronger positive association than the AC.To provide a theoretical foundation for ecological restoration in the norther branch of the Zhuozhang River Watershed,this study integrated niche characteristics and interspecific associations to understand the dominant species,their interrelations,dynamic characteristics of the communities and current wetland utilization.