Table 4.

Spatiotemporal variations of irrigation water quality in the Woybo irrigation scheme.

		Upstream		Downstream
Parameters	Unit	November	July	November	July	CV (%)
pH	Unitless	7.3	6.9	7.5	7.1	3.6
ECw	dS m−1	0.18	0.17	0.185	0.174	3.7
Ca2+	mg l−1	6	5	6.2	5.1	11
Mg2+	mg l−1	3	3	2.8	3.1	4.2
K+	mg l−1	7	6	7.2	6.7	7.8
Na+	mg l−1	22.3	20.5	20.7	21.8	4.1

		Upstream		Downstream
Parameters	Unit	November	July	November	July	CV (%)
SAR	Unitless	10.5	10.3	9.8	10.8	4.2
SO42−	mg l−1	0.002	0.003	0.0023	0.003	19.6
NO3−	mg l−1	3.9	4.5	4.2	6	20.1
PO43−	mg l−1	0.0025	0.0032	0.003	0.004	19.6
Fe2+,3+	mg l−1	1.4	1.2	1.5	1.23	10.7
Mn	mg l−1	0.001	0.0015	0.0017	0.0018	23.7
B	mg l−1	0.0013	0.0015	0.0018	0.002	18.8
Cu	mg l−1	0.0012	0.0014	0.0015	0.002	22.3

where CV is the coefficient of variations, and SAR is the sodium adsorption ratio.