Fig. 1

Diversity and taxonomy of microorganisms in the upstream tributaries, River Kaidu and Lake Bosten. a Comparison of α-diversity indexes of microbial communities. Diversity indexes were calculated using subset of 23,965 reads per sample. Horizontal bars in the box plots indicate median proportional values. Lower and upper edges of the boxes represent the approximate 1st and 3rd quartiles, respectively. The upper and lower whiskers extend to data no more than 1.5 times the interquartile range from the upper edge and lower edge of the box, respectively. Kruskal-Wallis test was performed to examine differences among the three sampling types. Different lower-case letters indicate significant differences (P < 0.05) among sampling types. b Unconstrained PCoA with Bray–Curtis distance showing that the microbial community in Lake Bosten separate from those in River Kaidu and the upstream tributaries using adonis analysis. Ellipses cover 80% of the data for each sampling type. c Phylum-level distribution of microbial communities of each sampling site