Table 2.

Variations of average of heavy metals concentration in Tembi River sediments in different seasons (mg/kg).

Heavy metals	Sampling point	Sampling time
		Summer 2011	Autumn 2011	Winter 2011	Spring 2012
Cd	1	14 ± 0.7	10 ± 0.5	10 ± 0.5	24 ± 1.00
	2	40 ± 1.1	20 ± 1.5	14 ± 0.5	24 ± 0.5
Cr	1	57 ± 1.5	40 ± 0.5	28 ± 2.0	42 ± 1.1
	2	74 ± 0.5	70 ± 2.0	11 ± 1.0	67 ± 4.0
Cu	1	70 ± 1.1	50 ± 1.0	37 ± 1.5	49 ± 1.0
	2	100 ± 2.6	66 ± 1.0	40 ± 1.7	54 ± 1.0
Fe	1	250 ± 6.0	230 ± 1.0	220 ± 1.0	230 ± 0.5
	2	280 ± 3.0	234 ± 2.0	210 ± 0.5	233 ± 1.05
Mn	1	715 ± 1.00	310 ± 16	310 ± 11	302 ± 12
	2	820 ± 2.5	310 ± 5.0	278 ± 5.0	341 ± 9.0
Ni	1	107 ± 2.0	63 ± 3.2	52 ± 2.9	129 ± 11
	2	150 ± 3.6	80 ± 7.6	87 ± 2.5	143 ± 7.0
Pb	1	240 ± 3.4	198 ± 2.3	141 ± 4.0	151 ± 5.0
	2	270 ± 0.5	236 ± 2.0	178 ± 3.3	210 ± 2.0
Zn	1	54 ± 2.0	30 ± 1.5	24 ± 2.0	32 ± 1.0
	2	74 ± 2.0	30 ± 1.5	21 ± 2.0	38 ± 1.0

1: upstream; 2: downstream.