Legacy Effects of Two Invasive Plant Species on Soil Bacterial Community Assembly, Diversity, and Functional Attributes

Biological invasions by exotic plant species are among the most significant threats to local biodiversity and ecosystem functioning. This study investigates the legacy effects of two invasive plant species, Solanum elaeagnifolium (perennial) and Conyza bonariensis (annual), on soil bacterial communities and their ecological assembly processes.To quantify microbial legacy effects, we conducted high-throughput sequencing of the 16S rRNA gene (ONT MinION) to assess bacterial taxonomic composition and community structure across different soil treatments. We analyzed beta diversity to measure shifts in community dissimilarity and network analyses to examine microbial co-occurrence patterns. Our approach examines bacterial community assembly mechanisms, distinguishing between deterministic (niche-based) and stochastic (neutral) processes. Additionally, we linked bacterial community assembly attributes to soil functionality by measuring the activity of six key soil enzymes involved in carbon (C), nitrogen (N), and phosphorus (P) cycles.