Abstract
Invasive plants pose a threat to production sustainability due to their detrimental effects on soil, food cycles, and hydrology. This study aimed to identify and analyze the effects of five invasive plant species on the rangelands of western Isfahan province, Iran. A random-systematic sampling of vegetation cover and soil was conducted at four rangeland sites, and mean soil characteristics were compared using one-way analysis of variance and Tukey's test. Parametric principal component analysis (PCA) and nonparametric multidimensional scaling (NMDS) analysis in CANOCO and PATN software were used to investigate the relationship between environmental factors and vegetation cover. Cluster analysis was employed for habitat grouping, and the Analytic Hierarchy Process (AHP) was utilized to analyze the risk of invasive plants. The analysis involved three main criteria, eight subcriteria, and five options. The compatibility ratio of each criterion was calculated using Expert Choice software to assess the accuracy of criteria weighting. Parametric ordination revealed significant correlations between the first and second principal components and mean annual precipitation, mean annual temperature, altitude, slope, nitrogen, and calcium. NMDS analysis revealed significant correlations between plant species and seven environmental variables in a three-dimensional ordination space (p < 0.05). Among the target species, Eryngium billardieri showed a positive correlation with rainfall, altitude, slope, calcium, nitrogen, and a negative correlation with mean annual temperature, rock, and gravel. However, the relationship of other species with environmental factors was not significant. Notably, Cousinia bachtiarica, Eryngium billardieri, Phlomis persica, Euphorbia decipiense, and Poa bulbosa exhibited the most destructive effects, respectively. The study results can inform targeted efforts to protect rangeland ecosystems against invasive plants. Furthermore, the study method is applicable for assessing the risk of other plant species in semiarid ecosystems.