土壤特性会影响植物种群动态以及本地和入侵植物的共存,从而可能影响群落结构和入侵趋势。然而,土壤理化性质对本地和入侵植物群落物种多样性和结构的不同影响尚不清楚。在这项研究中,我们在中国南北地理边界的地区共建立了30个空心莲子草入侵地块和30个控制区。我们比较了入侵植物群落和本地植物群落之间的物种组成差异,然后我们使用回归分析的方法,冗余分析(RDA),和规范对应分析(CCA),以研究土壤理化性质对四个α多样性指数以及这两种类型群落的物种分布的影响。我们发现,a.philoxeroides入侵增加了优势植物物种的重要性值之间的差异,入侵覆盖率与土壤速效钾(R2=0.135;p=0.046)和帕特里克丰富度指数(R2=0.322;p<0.001)呈负相关。在土著社区,物种多样性由土壤化学性质决定,帕特里克丰富度指数,辛普森优势指数,和香农-维纳多样性指数,随着土壤pH值的增加,有效钾,有机物,和铵态氮。然而,在被入侵的社区,物种多样性由土壤物理性质决定;Pielou均匀度指数随非毛管孔隙度的增加而增加,但随毛管孔隙度的增加而降低。原生群落物种分布的决定因素是土壤孔隙度和硝态氮,而入侵群落的决定因素是土壤容重和速效钾。此外,与土著社区相比,入侵群落中物种分布的聚集程度加剧。我们的研究表明,物种多样性和分布对紫草入侵和本地植物群落之间的土壤理化性质具有显着的异质性响应。因此,我们需要加强对入侵栖息地土壤性质的监测,并根据本地和入侵群落的异质性反应采取生物替代策略,以有效防止环境变化下植物入侵引起的生物均质化。
Soil properties can affect plant population dynamics and the coexistence of native and invasive plants, thus potentially affecting community structure and invasion trends. However, the different impacts of soil physicochemical properties on species diversity and structure in native and invaded plant communities remain unclear. In this study, we established a total of 30 Alternanthera philoxeroides-invaded plots and 30 control plots in an area at the geographical boundary between North and South China. We compared the differences in species composition between the invaded and native plant communities, and we then used the methods of regression analysis, redundancy analysis (RDA), and canonical correspondence analysis (CCA) to examine the impacts of soil physicochemical properties on four α-diversity indices and the species distribution of these two types of communities. We found that A. philoxeroides invasion increased the difference between the importance values of dominant plant species, and the invasion coverage had a negative relationship with the soil-available potassium (R2 = 0.135; p = 0.046) and Patrick richness index (R2 = 0.322; p < 0.001). In the native communities, the species diversity was determined with soil chemical properties, the Patrick richness index, the Simpson dominance index, and the Shannon-Wiener diversity index, which all decreased with the increase in soil pH value, available potassium, organic matter, and ammonium nitrogen. However, in the invaded communities, the species diversity was determined by soil physical properties; the Pielou evenness index increased with increasing non-capillary porosity but decreased with increasing capillary porosity. The determinants of species distribution in the native communities were soil porosity and nitrate nitrogen, while the determinants in the invaded communities were soil bulk density and available potassium. In addition, compared with the native communities, the clustering degree of species distribution in the invaded communities intensified. Our study indicates that species diversity and distribution have significant heterogeneous responses to soil physicochemical properties between A. philoxeroides-invaded and native plant communities. Thus, we need to intensify the monitoring of soil properties in invaded habitats and conduct biotic replacement strategies based on the heterogeneous responses of native and invaded communities to effectively prevent the biotic homogenization that is caused by plant invasions under environmental changes.