五大连池火山熔岩台地草本层物种多样性及环境解释

五大连池火山熔岩台地是一种火山地貌, 研究熔岩台地草本物种分布及其环境解释, 对认识火山原生演替过程中植物群落空间格局形成及适应机制具有重要意义。本文以五大连池熔岩台地的草本物种为研究对象, 调查了苔藓、草本、灌丛、阔叶林和针阔混交林等不同植被类型中的草本层样方, 并测定样方中的土壤养分和水分等状况, 采用多样性指数、优势度指数、均匀度指数、物种丰富度评价草本层物种多样性, 通过典范对应分析方法研究了群落组成与土壤因子的关系。结果表明: (1)熔岩台地草本层物种丰富, 共56种, 占本研究调查区总物种数的82.35%, 草本样地的草本层物种多样性、优势度和均匀性高于其他植被类型。(2)熔岩台地土壤pH值对群落草本层物种丰富度和物种个体的空间分布均有较大影响。(3)土壤因子解释了群落分布的79.39%, 其中土壤pH值、速效磷、硝态氮、铵态氮所占的解释量比较大。(4)岩败酱(Patrinia rupestris)、万年蒿(Artemisia sacrorum)、硬质早熟禾(Poa sphondylodes)和中华苦荬菜(Ixeris chinensis)对环境要求较低, 能够适应熔岩台地土壤贫瘠恶劣的环境。熔岩台地不同植被类型表现出对环境资源的特定需求, 熔岩地貌导致了土壤pH值、养分、水分的差异, 并影响植物群落的分布。

Species diversity and environmental interpretation of herb layer in lava platform of Wudalianchi,China

The Wudalianchi volcanic lava platform, a volcanic landscape, is important to understand plant community mechanisms to volcanic primary succession. In this paper, the herbaceous species of the Wudalianchi volcanic lava platform were studied, which belonged to bryophyte, herb, shrub, mixed-forest, and mixed coniferous and broad-leaved forest plots. Soil nutrients and soil moisture were also studied with the canonical correspondence analysis (CCA) method along with species diversity indices such as the Simpson, Shannon-Wiener, Pielou, and species richness indices. Our results show that: (1) There were 56 plant species in the herb layer, accounting for 82.35% of the total species in the volcanic platform while diversity, dominance, and evenness indices of the herb layer was higher than other vegetation types. (2) Soil pH had a considerable influence on species richness and spatial distribution of herbaceous species in the herb layer. (3) Soil factors accounted for 79.39% of the community’s distribution, among which soil pH, available phosphorus, nitrate nitrogen, and ammonium nitrogen accounted for a large proportion. (4) Patrinia rupestris, Artemisia sacrorum, Poa sphondylodes, and Ixeris chinensis had low environmental requirements and adapted uniquely to the poor environment of the lava platform. Vegetation within the platform showed specific resource demands, which are due to differences in lava type that alter soil water, pH, and soil nutrients, thereby impacting plant community distributions.