Fig. 4

Predictive functional potential of microbial communities in Antarctic lake samples, inferred from 16Â S rRNA gene amplicon data using PICRUSt2. Functional profiles were clustered by sample (columns) based on hierarchical clustering with Pearson correlation distance and visualized as a heatmap with the pheatmap package in R (v4.3.1). Sample types are indicated by color-coded labels: blue for water samples and brown for sediment samples. Symbols represent different sample categories. Abundance values are shown as a color gradient, with black indicating zero values.