长治城市湿地公园滨岸区植物群落特征及其与土壤环境的关系

Species composition and soil gradient analysis of plant communities in the waterside zone of Changzhi National Urban Wetlands Park

湿地生境的保护与恢复是当前城市湿地公园建设面临的重大挑战,而相关研究案例极少。通过对山西长治城市湿地公园滨岸区草本植物群落进行调查和多元分析,探讨物种分布与土壤因子之间的关系。结果如下:1)研究区植物共计20个种,以湿、中生植物为主,芦苇为建群种,优势种包括香蒲、早熟禾、扁杆藨草和苍耳,总体上物种丰富度较低,随着逐渐远离水域,物种丰富度、优势度和均匀度均呈递增趋势,物种组成上呈现水-湿生、湿-中生、中-旱生的梯度序列;2)CCA排序和Monte Carlo检验结果表明,土壤氮含量和水分含量是影响研究区植物群落分布的重要环境因子,二者分别可解释1.7%、1.4%的物种分布差异,较大的未被解释的部分表明研究区植物群落分布在很大程度上受到其他未选取因子的影响,如种间竞争、水位变化、人为干扰或随机因子。

Wetlands provide many important ecosystem services to human society. Thus, urban wetland park construction aiming at a simultaneous increase in nutrient retention and species diversity in urban area has recently become applied as a compensation measure for past disorder exploitation and activities. A lack of information on ecological function and process of wetlands, especially mechanism of plant diversity maintain, has restricted development of wetland park in urban. To fill this information gap, soil characteristics were correlated with plant species diversity in Changzhi Urban Wetland Park, located in southeast Shanxi, China. The occurrence and distribution of herbaceous plants were investigated on 225 plots along 15 transects in the waterside zone . The occurrence and distribution of herbaceous plants were investigated on 225 plots along 15 transects in the waterside zone . The relationship between the distribution and abundance of herbaceous species and environmental gradients was analyzed using the canonical correspondence analysis （CCA） ordination method. Forward selection and Monte Carlo permutation test were used to select the factors significantly determine the herbaceous plant distribution. Partial CCA （PCCA） was also performed to partition the variance that was explainable by factors studied.There are 20 species were observed in the studying area, belonging to 13 families and 20 genus, and most of them are hygrophytes and mesophytes. In order of the important value （ IV）, the dominant species are Phragmites, Typha, Poa, Scripus and Xanthium. Increasing trends in species richness, Shannon-Weiner information, Simposon Index and Pielou uniformity with increasing distance from water were observed. Overall the community showed low species diversity. Forward selection and Monte Carlo test suggested that soil nitrogen and soil moisture were the most important factors determining plant distribution. PCCA revealed that soil nitrogen and soil moisture explained 1.7% and 1.4% of variance in the distribution of herbaceous plants. However, the fact that majority of the variance was unaccounted for by the factors studied suggests that other factors we did not measure could play a vital role in determining the occurrence and distribution of herbaceous plants in the waterside zone, e.g., interspecific competition, water level fluctuation, human activities and random events.