Seasonal Dynamics in Bacteriological and Physicochemical Water Quality of the Southern Gulf of Lake Tana

Table 2

Median count (standard error) of coliform counts in water samples collected from Southern Gulf of Lake Tana (n = 36), 2021.

Coliform	Site	Season	Median (SE)	Range	Mean rank	Mann–Whitney U test	-Value (asymp. sign)
FC	Impacted	Dry	14 (9.2)	1-280	53.86	59	≤0.01
	Reference	Dry	1 (0.23)	1-7	20.14
	Impacted	Wet	1600 (123.7)	2-1600	40.5	505	0.86
	Reference	Wet	350 (120.8)	2-1600	32.5
	Impacted	Dry	14 (9.2)	1-280	23.03	235	≤0.01
	Impacted	Wet	1600 (123.7)	2-1600	47.97
	Reference	Dry	1 (0.23)	1-7	19.575	38.5	≤0.01
	Reference	Wet	350 (120.8)	2-1600	53.43
TC	Impacted	Dry	1600 (70.4)	500-1650	52.68	65	≤0.01
	Reference	Dry	14 (67.06)	1-1650	20.32
	Impacted	Wet	1600 (46.6)	500-1600	36.85	635.5	0.815
	Reference	Wet	1600 (90.2)	2-1600	36.15
	Impacted	Dry	1600 (70.4)	500-1650	30.4	543.5	0.186
	Impacted	Wet	1600 (46.6)	500-1600	33.60
	Reference	Dry	14 (67.06)	1-1650	23.57	182.5	≤0.01
	Reference	Wet	1600 (90.2)	2-1600	49.43

Note. Impacted sites (sites 1 to 4); Reference sites (sites 5 to 8).