. 2023 Jul 21;9(8):e18518. doi: 10.1016/j.heliyon.2023.e18518

Table 1.

Water quality averages in fish ponds with and without cyanobacteria blooms at different hydrological seasons, rainy and dry.

Variables	With blooms			Without blooms			General averages		p value
Variables	Rainy	Dry	p value	Rainy	Dry	p value	Rainy	Dry	p value
Temperature (°C) in situ	27.17 ± 1.36^a	29.33 ± 1.47^a	*ns	27.60 ± 1.38^a	29.03 ± 1.45^a	*ns	27.39 ± 1.37^a	29.18 ± 1.46^a	*ns
pH	6.67 ± 0.45^a	7.01 ± 0.47^a	*ns	6.02 ± 0.40^b	7.33 ± 0.49^a	0.0345	6.35 ± 0.43^a	7.17 ± 0.48^a	*ns
Dissolved oxygen (mg L⁻¹)	6.13 ± 0.44^a	3.00 ± 0.22^b	0.0140	6.00 ± 0.43^a	3.10 ± 0.22^b	0.0125	6.07 ± 0.44^a	3.05 ± 0.22^b	0.0120
Water transparency (cm)	40.02 ± 5.60^a	32.29 ± 4.52^b	0.2550	49.40 ± 6.92^a	36.67 ± 5.13^b	0.0275	44.71 ± 6.26^a	34.48 ± 4.83^a	*ns
Nitrate (NO₃¹⁻)	0.35 ± 0.08^a	0.15 ± 0.03^b	0.0330	0.30 ± 0.07^a	0.15 ± 0.03^b	0.3565	0.33 ± 0.07^a	0.15 ± 0.03^b	0.03825
Nitrite (NO₂¹⁻)	0.15 ± 0.04^a	0.05 ± 0.01^b	0.0440	0.10 ± 0.03^a	0.05 ± 0.01^b	0.0422	0.13 ± 0.03^a	0.05 ± 0.01^b	0.04334
Total ammonia (mg L⁻N-NH₄)	0.10 ± 0.03^a	0.13 ± 0.04^a	*ns	0.10 ± 0.03^a	0.13 ± 0.04^a	*ns	0.10 ± 0.03^a	0.13 ± 0.04^a	*ns
Phosphate (PO₄³⁻)	1.00 ± 0.20^b	2.26 ± 0.45^a	0.0095	0.60 ± 0.12^b	1.55 ± 0.31^a	0.0099	0.80 ± 0.16^b	1.91 ± 0.38^a	0.0745
Phosphorus (P)	0.41 ± 0.10^b	0.90 ± 0.22^a	0.0388	0.22 ± 0.05^b	0.66 ± 0.16^a	0.0410	0.32 ± 0.08^b	0.78 ± 0.19^a	0.0444
Alkalinity (mg L⁻¹ CaCO₃)	44.55 ± 6.24^a	31.43 ± 4.40^b	0.0234	48.10 ± 6.73^a	37.64 ± 5.27^b	0.0287	46.33 ± 6.49^a	34.54 ± 4.83^b	0.0356
Water hardness (mg L⁻¹ CaCO₃)	50.10 ± 6.01^a	28.57 ± 3.43^b	0.0195	54.20 ± 6.50^a	34.85 ± 4.66^b	0.0208	52.15 ± 6.26^a	31.71 ± 3.80^b	0.0169

If there are different letters (^a,b) between the columns, it is different (p < 0.05) by Student's t-test; *ns – not significant (p > 0.05).