Assessing the Industrial Effluent Effect on Irrigation Water Quality and Farm Soil near Kombolcha Town, Ethiopia

Table 6

The characteristics of downstream Borkena irrigated farm soil during the dry and wet period.

Parameter	Units	1^st irrigation phase (April)				2^nd irrigation phase (May)				3^rd irrigation phase (June)
		Composite surface	Subsurface (cm)			Composite surface	Subsurface (cm)			Composite surface	Subsurface (cm)
			0–30	30–60	60–90		0–30	30–60	60–90		0–30	30–60	60–90
EC	ds/m	0.8	0.8	0.7	0.7	0.9	0.9	0.8	0.8	0.7	0.6	0.6	0.6
Mg^+2	mg/l	4.6	4.3	4.0	3.6	4.8	4.7	4.6	4.5	4.1	4.0	3.9	3.8
Ca^+2	mg/l	17.4	17.2	16.9	16.5	18.6	18.6	18.3	17.8	17.1	16.8	16.7	16.3
Na^+	mg/l	19.8	19.6	19.6	19.3	21.9	22.2	22.1	21.5	19.0	18.8	18.6	18.1
Cl^−	mg/l	86.3	81.0	78.3	63.3	118.3	114.3	106.7	86.0	71.3	69.0	65.0	52.7
pH	0–14	8.5	8.6	8.6	8.6	8.3	8.4	8.4	8.4	7.9	8.0	8.0	8.0
CO3^−2	mg/l	0.5	0.7	0.7	0.7	0.7	0.7	0.8	0.9	0.5	0.6	0.6	0.6
HCO3^−	mg/l	9.4	9.7	9.9	8.8	11.5	11.9	12.1	12.0	8.5	9.5	10.0	9.7
Fe	mg/l	3.8	3.6	3.5	3.4	5.1	4.8	4.6	4.5	3.5	3.4	3.3	3.1
Mn	mg/l	0.1	0.1	0.1	0.1	0.3	0.3	0.2	0.1	0.1	0.1	0.0	0.0
Pb	mg/l	0.3	0.3	0.2	0.1	0.4	0.3	0.2	0.0	0.3	0.3	0.2	0.2
Cu	mg/l	0.2	0.2	0.1	0.1	0.3	0.3	0.3	0.2	0.1	0.1	0.1	0.0
Cr	mg/l	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.1	0.1	0.1	0.0
Cd	mg/l	< L.D	< L.D	< L.D	< L.D	< L.D	< L.D	< L.D	< L.D	< L.D	< L.D	< L.D	< L.D
Ni	mg/l	0.1	0.1	0.1	< L.D	0.3	0.2	0.1	< L.D	0.2	0.1	0.1	0.1
TDS	mg/l	512.0	486.4	467.2	426.7	580.3	554.7	529.1	512.0	433.1	411.7	398.9	352.0

Ca⁺: calcium; Cd: cadmium; Cl⁻: chloride; CO₃⁻²: carbonate; Cr: chromium; Cu: copper;EC: electrical conductivity; Fe: iron; HCO₃⁻: bicarbonate; Mg⁺²: magnesium; Mn: manganese; Na⁺: sodium; Ni: nickel; Pb: lead; SAR: specific absorption rate; TDS: total dissolved solids; < L.D: less than the limit of detection.