Table 4.

Statistics of the data for the TOC ^a (g/kg), Fe (mg/kg), and pH (in unit).

	n	Min.	Max.	Mean	SD
TS1
TOC	22	4.13	15.45	5.90	2.57
Fe	22	43.59	99.21	84.81	11.94
pH	22	5.86	6.78	6.34	0.22
TS2
TOC	10	4.16	18.83	7.66	4.48
Fe	5	68.92	106.97	82.33	15.28
pH	10	4.93	6.12	5.49	0.47
TS3
TOC	20	0.40	5.62	1.13	1.32
Fe	10	1.52	66.44	11.12	19.89
pH	20	4.66	5.86	5.51	0.29
TS4
TOC	59	0.42	7.45	1.58	1.20
Fe	20	5.13	150.76	26.68	31.74
pH	59	5.44	6.72	6.12	0.35
TS5
TOC	59	0.34	2.78	1.26	0.55
Fe	30	2.79	289.18	59.14	83.11
pH	59	4.40	8.62	6.58	1.39
TS6
TOC	10	0.94	11.92	2.76	3.35
Fe	6	1.90	7.49	3.02	2.20
pH	10	4.92	5.26	5.10	0.14

^a TOC data are from a study by Zhou et al. [44].