From: Assessment of soil quality for agricultural purposes around the Barapukuria coal mining industrial area, Bangladesh: insights from chemical and multivariate statistical analysis
Cluster
Sample number
Sample percentage
Cluster 1
1,5,7,8,12,14,16,17,18
50
Cluster 2
2,3,6,9,11,13,15
38.9
Cluster 3
4,10
11.1