Fig. 3

Correlation analysis of sample. Note: (A) The PC1 coordinate indicates the first principal component, while the percentage in parentheses indicates the contribution of the first principal component to the sample variance; the PC2 coordinate indicates the second principal component, while the percentage in parentheses indicates the contribution of the second principal component to the sample variance. B The coloured points in the graph indicate the individual samples respectively. Both the horizontal and vertical coordinates in the graph are for each sample, and the colour shade indicates the size of the correlation coefficient between the two samples. The closer the colour is to red, the higher the correlation, and the closer the colour is to blue, the lower the correlation