Data and code for: Rapid expansion of the eastern China lineage (haplotype P) of Phragmites australis in Caohai Lake, Guizhou, China

This dataset contains the code and supporting data used to generate key results in the study of Phragmites australis at Caohai Lake. The Figure_3_map.R script visualizes the habitat suitability GeoTIFF file (located in the data folder) predicted by the MaxEnt model and extracts the specific habitat suitability index value for the Caohai Lake area. The Figure_4_area.R script processes the historical distribution data from data/Area.txt to create a line chart illustrating the changes in the reed population's area over time. The Haplotype.xlsx file provides the geographical coordinates (latitude and longitude) for the 11 sampling sites at Caohai Lake and documents the assigned chloroplast haplotype (P) for all collected P. australis individuals. These materials directly support the creation of Figures 3 and 4 and the haplotype analysis results presented in the manuscript.