Table 3.3 Summary Statistics of Water Quality of Sha Chau and Lung Kwu Chau Marine Park in 1997 – 2000
|
Parameter |
|
Monitoring Station |
WPCO WQOs (in marine waters) |
|||
|
|
|
SE Sha Chau |
Pak Chau |
|
||
|
Temperature (oC) |
|
24.0 (10.0 – 30.3) |
24.1 (10.0 – 30.0) |
24.2 (10.0 – 34.0) |
24.2 (10.0 – 31.0) |
natural daily level ± 2 oC |
|
Salinity (ppt) |
|
26.5 (3.0 – 36.9) |
26.4 (3.0 – 36.2) |
26.7 (3.0 – 36.2) |
26.3 (2.5 – 36.9) |
natural ambient level ± 10 % |
|
DO (mg L-1) |
Surface |
6.9 (4.4 – 8.5) |
6.9 (4.4 – 9.0) |
6.9 (4.6 – 8.9) |
6.9 (4.4 – 8.8) |
³ 4 mg L-1 |
|
|
Bottom |
5.6 (1.9 – 8.6) |
6.0 (3.5 – 9.0) |
6.1 (3.1 – 8.7) |
6.0 (2.4 – 8.9) |
³ 2 mg L-1 |
|
pH value |
|
8.1 (7.6 – 8.4) |
8.1 (7.6 – 8.4) |
8.1 (7.7 – 8.4) |
8.1 (6.7 – 8.3) |
6.5 - 8.5 (± 0.2 from natural range) |
|
Turbidity (NTU) |
|
15.6 (1.0 – 146.0) |
9.67 (0.5 – 42.1) |
13.22 (0.7 – 85.0) |
11.8 (0.85 – 44.0) |
- |
|
SS (mg L-1) |
|
13.0 (3.0 – 113.0) |
11.5 (2.0 – 36.0) |
12.1 (3.0 – 35.0) |
13.4 (3.0 – 39.9) |
£ natural ambient level +30% |
|
BOD5 (mg L-1) |
|
0.80 (0.01 – 2.27) |
0.80 (0.05 – 1.99) |
0.80 (0.04 –2.31) |
0.83 (0.14 –2.14) |
not applicable to marine waters |
|
Ammoniacal Nitrogen (mg L-1)* |
|
0.17 (0.02 – 0.64) |
0.17 (0.01 – 0.76) |
0.17 (0.02 – 0.76) |
0.16 (0.03 – 0.72) |
- |
|
Total Inorganic Nitrogen (mg L-1)* |
|
1.56 (0.03 – 8.29) |
1.61 (0.04 – 8.87) |
1.56 (0.04 – 7.68) |
1.61 (0.04 – 8.87) |
£ 0.5 mg L-1 |
|
Total Phosphorus (mg L-1)* |
|
0.10 (<0.02 – 0.31) |
0.10 (<0.02 – 0.62) |
0.08 (<0.02 – 0.35) |
0.10 (<0.02 – 0.65) |
- |
|
Chlorophyll-a (µg L-1) |
|
2.94 (0.21 – 16.3) |
2.8 (0.5 – 22.4) |
6.5 (0.3 – 16.0) |
2.6 (0.5 – 19.7) |
- |
|
Unionized Ammonia (mg L-1)** |
|
0.04 (0.01 – 0.09) |
0.04 (0.0 – 0.09) |
0.04 (0.01 – 0.11) |
0.04 (0.01 – 0.11) |
£ 0.021 mg L-1 |
|
E.coli (colonies/ 100ml)** |
|
90.2 (0.0 – >200) |
63.5 (0.0 – >200) |
65.4 (0.0 – >200) |
39.4 (0.0 – 97.5) |
|
Notes: