Study was conducted with the aim to understand the temporal and spatial variations of water quality parameters (temperature, salinity, pH, DO, TSS, NO 3 -, NO 2 -, NH 3-N and PO 4-P, and phytoplankton cell density) in Ambong Bay, Sabah, Malaysia in order to provide reference for future mariculture development in the bay. Samplings were carried out once a month in two stations (coastal and open sea) within the bay for 12 months period from September 2015 to August 2016. Results showed that there were significant differences in pH and NO 2 - when compared spatially, whereas salinity, DO, TSS, phytoplankton cell density, NO 3 -, NH 3-N, and PO 4-P were temporally significant. The fermentation processes by anaerobic bacteria, organic acids from decaying vegetation and acidic clays in the mangrove soils might explain the significant spatial differences in pH and NO 2 -. The bay was dominated by dinoflagellate, Prorocentrum spp. (mean abundance of 16.23% and 24.44%, respectively) a potentially toxic algae species. Correlation matrix showed that NH3-N was positively correlated with PO 4-P (r = 0.475, p < 0.05) but negatively correlated with salinity (r = –0.517, p < 0.01). Besides, salinity was positively correlated with DO (r = 0.505, p < 0.05) and TSS (r = 0.408, p < 0.05). In addition, DO and TSS were also positively correlated (r = 0.451, p < 0.05). Phytoplankton cell density was positively correlated with TSS (r = 0.644, p < 0.01). In general, the water quality in Ambong Bay is within the standard values permitted by the Malaysia Marine Water Quality standard for marine life, fisheries, coral reefs, recreational and mariculture (Class 2), except for NO 3 -. In conclusion, any mariculture operation to take place in Ambong Bay in the near future should take the temporal variation of the water quality into account. Moreover, effects of toxic phytoplankton to culture fishes should also be taken care and monitored frequently.
Quality of seawater plays important role in human health, marine organisms and ecosystem. Good water quality is also needed to maintain feasible aquaculture production because water is necessary requirement for fish farming. Fish perform all its physiological activities in the water. Thus, the maintenance of good water quality is essential for survival and optimum growth of culture organisms, as well as the success or failure of an aquaculture operation [
Physical properties of seawater include temperature and total suspended solids (TSS), are factors which determine the equilibrium structure in the marine ecosystem, whereas chemical characteristics such as pH, dissolved oxygen (DO), salinity, and water nutrients (e.g. nitrogen and phosphorus) are crucial in biological productivity because of its influence on physiological processes inaquatic organisms [
Ambong Bay is situated in the Southern part of Kota Belud, about 50 km north of Kota Kinabalu, the capital city of Sabah. The bay is shared and governed by Tuaran and Kota Belud district offices. The inner part of the bay is fringed by mangrove forests while the outer part is formed by beautiful sandy beach [
Mangrove habitats are known to be an important spawning, breeding and nursery ground for many fishes and prawns [
Samplings were carried out once a month in Ambong Bay, Sabah for 12 months period (September 2015-August 2016). Sampling stations were situated nearby Kampung Baru-Baru (
Temperature (˚C), salinity (psu), pH, and dissolved oxygen (mg/l) of the seawater at 0.5 m below water surface were measured in-situ using a multi-function environmental sensor (YSI, Loveland. Co, USA). Water samples were collected at 0.5 m below water surface using a Van Dorn water sampler for total suspended solids (TSS) and phytoplankton cell density analyses.
In laboratory, water samples were filtered through GF/C glass microfiber filters (Whatman™, No. 1822-047) for TSS analysis. Filtered water samples were then stored in refrigerator (4˚C) for water nutrients analysis. The inorganic nutrients,
including total dissolved phosphorus (PO4-P), total ammonia-nitrogen (NH4-N), nitrate ( NO 3 − ) and nitrite ( NO 2 − ) were analyzed following [
The filters for TSS analysis were then dried to constant weight in an oven for 24 hours at 105˚C. The difference in weight over that of the fully dried empty filters represents the TSS (mg/L) [
For phytoplankton cell counting, the water samples were preserved with Lugol’s solution in the field. In the laboratory, samples were poured into a one litre measuring cylinder and left concentrated for 24 hours using Utermöhl sedimentation method [
Data on rainfall for Ambong Bay area was obtained from Malaysia Meteorological Department.
Statistical analyses were performed using the SPSS statistics software. Tests were judged to be significant at p < 0.05 level. Pearson’s correlation coefficient test was performed to evaluate the relationship between the water parameters. One- way ANOVA test was applied to test for significant differences in environmental variables, water nutrients, and phytoplankton cell density among stations and months.
The summary of waters parameters (mean ± SE, range) at the coastal and open sea stations in Ambong Bay from September 2015 to August 2016 is shown in
Parameters | Coastal Station | Open Sea Station | ||
---|---|---|---|---|
Mean ± SE | Range | Mean ± SE | Range | |
Temperature (˚C) | 31.42 ± 0.32 | 30.0 - 33.2 | 30.83 ± 0.36 | 28.3 - 33.1 |
pH | 7.67 ± 0.08 | 7.45 - 8.07 | 7.89 ± 0.06 | 7.56 - 8.30 |
Salinity (psu) | 33.22 ± 0.42 | 30.75 - 34.94 | 33.08 ± 0.38 | 30.98 - 34.61 |
DO (mg/l) | 5.04 ± 0.26 | 3.12 - 6.60 | 5.60 ± 0.29 | 3.66 - 7.00 |
TSS (mg/l) | 0.0515 ± 0.020 | 0.0182 - 0.2672 | 0.0454 ± 0.024 | 0.0133 - 0.2756 |
N O 3 − (mg/l) | 0.3091 ± 0.0823 | 0.0805 - 0.9898 | 0.1850 ± 0.0386 | 0.0305 - 0.4562 |
N O 2 − (mg/l) | 0.0009 ± 0.0002 | 0.0002 - 0.0023 | 0.0004 ± 0.0001 | 0.0001 - 0.0008 |
PO4-P (mg/l) | 0.0078 ± 0.0013 | 0.0027 - 0.0188 | 0.0066 ± 0.0008 | 0.0041 - 0.0107 |
NH3-N (mg/l) | 0.0464 ± 0.0035 | 0.0278 - 0.0642 | 0.0443 ± 0.0046 | 0.0282 - 0.0834 |
Phytoplankton density (cell/ml) | 5.30 ± 2.61 | 0.81 - 26.55 | 5.39 ± 2.36 | 0.64 - 24.96 |
As shown in
The pH measurements recorded in the two stations are presented in
be affected by water discharges from household and aquaculture activities. For marine organisms, the optimum pH is usually between pH 7.5 - 8.5 [
Salinity was the highest in February 2016, measured at 34.94 psu and lowest in June 2016, at 31.57 psu for coastal station (
Maximum DO recorded in coastal and open sea stations was 6.60 mg/l and 6.80 mg/l in March 2016 respectively, whereas minimum DO was 3.12 mg/l in coastal station and 3.66 mg/l in open sea station during September 2015 (
5.60 ± 0.29 mg/l in open sea and 5.04 ± 0.26 mg/l in coastal station (
Both coastal and open sea stations recorded highest TSS in March 2016 at 0.2672 mg/l and 0.2756 mg/l (
showed the TSS in both stations did not vary significantly (p > 0.05) spatially but variation seemed significant (p < 0.05) when compared temporally especially in March 2016. Study by [
In general, total ammonia-nitrogen (NH3-N) in coastal station was slightly higher than in the open sea, with mean concentration of 0.0464 ± 0.0035 mg/l and 0.0443 ± 0.0046 mg/l respectively (
The mean values of nitrite ( NO 2 − ) ranged from 0.0009 ± 0.0002 mg/l in coastal station to 0.0004 ± 0.0001 mg/l in open sea station (
at 0.0072 ± 0.0013 mg/l and 0.0056 ± 0.0009 mg/l respectively (
Distribution of nutrients is mainly influenced by season, tidal conditions and freshwater flow from land source [
NO 2 − is the intermediate product from NH4-N to NO 3 − during the process of nitrification and denitrification [
A total of 34 phytoplankton genera, representatives of 28 families, were identified from the two stations: 33 genera and 25 families in coastal station (
Mariculture is a branch of aquaculture, where aquatic organisms (e.g. fish and shellfish) are cultured and harvested in marine environment. Site selection for mariculture based on seawater quality aspect is one of the important factors that determine the production and mortality [
Phytoplankton Genus (Family) | Sept’15 (%) | Oct'15 (%) | Nov'15 (%) | Dec'15 (%) | Jan'16 (%) | Feb'16 (%) | Mac'16 (%) | Apr'16 (%) | May'16 (%) | June'16 (%) | July'16 (%) | Aug'16 (%) |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chaetoceros (Chaetocerotaceae) | 72.93 | 88.03 | 19.61 | 0.22 | 1.22 | 21.42 | - | 1.30 | - | 1.77 | - | 0.63 |
Thalassionema (Thalassionemataceae) | 7.01 | 2.48 | 24.74 | 15.23 | 15.52 | 13.95 | 6.10 | 22.22 | 15.00 | 13.96 | 15.79 | 23.76 |
Pleurosigma (Pleurosigmataceae) | 7.96 | 2.04 | 11.01 | 6.80 | 13.21 | 11.27 | 0.97 | 7.62 | - | 10.25 | 6.11 | 9.63 |
Navicula (Naviculaceae) | 5.12 | 1.02 | 5.13 | 7.19 | 29.68 | 22.23 | 1.26 | 10.70 | 4.88 | 8.01 | 10.85 | 7.33 |
Nitzschia (Bacillariaceae) | 1.55 | 0.83 | 6.49 | 6.44 | 6.22 | 1.87 | 0.73 | 4.85 | 1.16 | 7.90 | 3.33 | 0.97 |
Bacteriastrum (Chaetocerotaceae) | 0.27 | 0.29 | - | 0.22 | - | - | - | - | - | 1.78 | - | 0.93 |
Protoperidinium (Protoperidiniaceae) | 0.87 | 0.36 | 4.07 | 17.49 | 2.40 | 0.03 | 0.56 | 5.56 | 9.17 | 2.60 | 5.82 | 7.38 |
Asterolampra (Asterolampraceae) | 0.46 | 0.09 | - | 0.11 | 1.03 | 0.91 | 0.03 | 0.39 | 0.39 | - | - | 0.98 |
Pseudonitzschia (Bacillariaceae) | 0.64 | 1.86 | 5.13 | 3.75 | 6.44 | 1.05 | 0.32 | 3.98 | 0.39 | 9.48 | 1.55 | 0.66 |
Dactyliosolen (Rhizosolenaceae) | - | 0.04 | 4.83 | - | 0.20 | 0.13 | - | 1.77 | - | - | - | - |
Cosinodiscus (Coscinodiscaceae) | 1.82 | 2.13 | 8.90 | 7.97 | 9.74 | 8.90 | 0.12 | 3.50 | 4.58 | 14.80 | 5.21 | 9.96 |
Rhizosolenia (Rhizosoleniaceae) | 0.38 | 0.23 | 1.06 | 0.55 | 4.59 | 0.15 | 0.12 | 3.09 | - | 2.44 | - | 3.51 |
Amphiprora (Amphiporidae) | - | 0.12 | - | 0.33 | - | - | - | - | - | - | - | - |
Eucampia (Biddulphiaceae) | - | 0.05 | 0.15 | - | - | 0.12 | - | - | - | - | - | - |
Dytilum (Lithodesmiaceae) | - | 0.03 | 0.75 | 0.11 | - | - | - | - | - | - | 0.52 | - |
Lauderia (Lauderiaceae) | - | 0.07 | - | - | 2.83 | - | - | - | - | - | - | - |
Guinardia (Rhizosoleniaceae) | - | 0.23 | - | - | 0.53 | - | - | - | 0.72 | - | - | - |
Odontella (Eupodiscaceae) | 0.23 | 0.01 | 2.87 | 0.32 | 0.25 | 6.06 | - | 0.88 | - | 0.88 | 1.09 | 1.90 |
Melosira (Melosiraceae) | - | - | 0.60 | - | 0.25 | - | - | - | - | 0.73 | - | - |
Skeletonema (Skeletonemataceae) | - | - | 0.60 | 0.10 | - | - | - | - | - | - | - | - |
Fragilariopsis (Fragilariaceae) | - | - | 0.45 | - | 0.84 | 0.14 | 0.29 | 0.44 | - | - | - | - |
Gymnodinium (Gymnodiniidae) | - | - | - | 7.36 | - | - | 0.03 | 0.44 | 1.17 | 0.81 | 0.55 | 0.99 |
Thalassiothrix (Thalassionemataceae) | - | - | - | 1.08 | 1.42 | - | - | 0.90 | 1.20 | 0.81 | 0.55 | - |
Biddulphia (Biddulphiaceae) | - | - | - | 0.10 | - | - | - | 1.23 | - | - | - | - |
Diploneis (Diploneidaceae) | 0.30 | - | - | 0.33 | 0.83 | 0.87 | 0.12 | 0.99 | 0.39 | - | 0.50 | 0.64 |
Leptocylindrus (Leptocylindraceae) | - | - | - | - | 0.20 | - | - | - | - | - | - | - |
Hemiaulus (Hemiaulacea) | - | - | - | - | - | 0.04 | - | - | - | - | - | - |
Meuniera (Naviculaceae) | - | - | - | - | - | - | - | 0.94 | - | - | - | - |
Gonyaulax (Gonyaulacaceae) | - | - | - | - | - | - | - | 0.44 | 0.36 | - | - | 1.31 |
Haslea (Naviculaceae) | - | - | - | - | - | - | - | - | - | - | 11.07 | 15.30 |
Prorocentrum (Prorocentraceae) | 0.19 | 0.06 | 2.56 | 20.67 | 1.83 | 8.86 | 88.12 | 2.43 | 33.30 | 21.96 | 8.69 | 6.10 |
Ceratium (Ceratiacae) | 0.27 | 0.01 | 0.75 | 2.85 | 0.78 | 2.00 | 1.23 | 24.59 | 10.34 | 1.80 | 20.16 | 7.39 |
Dinophysis (Dinophysiaceae) | - | - | 0.30 | 0.73 | - | 0.03 | - | 1.73 | 16.94 | - | 8.23 | 0.65 |
Total count (cells/ml) | 6.62 | 17.31 | 1.66 | 2.15 | 0.6 | 5.73 | 24.96 | 0.76 | 1.41 | 0.62 | 0.71 | 1.08 |
No. of family | 14 | 16 | 16 | 18 | 17 | 17 | 13 | 18 | 12 | 14 | 13 | 16 |
No. of genera | 15 | 20 | 19 | 22 | 21 | 19 | 14 | 22 | 15 | 16 | 16 | 19 |
Phytoplankton Genus (Family) | Sept'15 (%) | Oct'15 (%) | Nov'15 (%) | Dec'15 (%) | Jan'16 (%) | Feb'16 (%) | Mac'16 (%) | Apr'16 (%) | May'16 (%) | June'16 (%) | July'16 (%) | Aug'16 (%) |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chaetoceros (Chaetocerotaceae) | 67.37 | 50.71 | 22.72 | 1.63 | - | 16.47 | 0.09 | 5.11 | - | - | - | 0.46 |
Thalassionema (Thalassionemataceae) | 14.99 | 11.02 | 12.11 | 11.10 | 2.73 | 29.64 | 11.30 | 36.29 | 4.83 | 6.80 | 19.34 | 46.49 |
Pleurosigma (Pleurosigmataceae) | 0.97 | 9.98 | 1.94 | 1.30 | 1.32 | 12.04 | 1.66 | 3.04 | 6.18 | 0.63 | 3.36 | 13.64 |
Navicula (Naviculaceae) | 0.17 | 1.36 | 1.35 | 0.88 | 4.04 | 5.50 | 2.60 | 3.03 | 13.37 | 2.30 | 1.08 | 0.57 |
Nitzschia (Bacillariaceae) | 0.46 | 2.06 | 5.23 | 2.30 | 2.19 | 4.43 | 1.39 | 0.85 | 0.42 | 1.90 | 2.73 | 1.32 |
Bacteriastrum (Chaetocerotaceae) | 1.71 | 0.90 | 0.15 | - | - | - | - | - | - | - | - | 0.59 |
Protoperidinium (Protoperidiniaceae) | 4.50 | 4.61 | 3.44 | 11.39 | 9.19 | 0.89 | 6.94 | 23.53 | 4.73 | 8.25 | 7.39 | |
Pseudonitzschia (Bacillariaceae) | 0.23 | 6.06 | 0.45 | 0.44 | 2.32 | 6.62 | 0.08 | 1.71 | 1.30 | 1.19 | 0.54 | 2.87 |
Cosinodiscus (Coscinodiscaeae) | 1.42 | 5.77 | 1.35 | 4.80 | 7.17 | 7.99 | 0.41 | 4.25 | 0.99 | 9.40 | 8.33 | 7.89 |
Rhizosolenia (Rhizosoleniaceae) | 0.91 | 3.05 | 1.35 | 2.49 | 1.02 | 0.66 | 0.04 | 7.98 | - | 0.42 | 1.70 | 4.37 |
Lauderia (Lauderiaceae) | - | 0.81 | 0.30 | - | - | - | - | - | - | - | - | - |
Odontella (Eupodiscaceae) | - | 0.12 | 0.60 | 0.11 | - | 6.13 | - | 2.51 | - | - | 1.11 | 0.75 |
Guinardia (Rhizosoleniaceae) | 0.28 | 0.70 | 0.60 | - | - | 0.34 | - | 0.42 | 0.49 | - | - | - |
Asterolampra (Asterolampraceae) | 0.06 | 0.26 | - | - | 0.11 | 0.54 | 0.40 | - | - | - | - | - |
Dytilum (Lithodesmiaceae) | - | 0.03 | - | - | - | 0.51 | - | 0.83 | - | - | - | 0.53 |
Skeletonema (Skeletonemataceae) | - | 0.64 | - | - | - | - | - | - | - | - | - | - |
Gymnodinium (Gymnodiniidae) | - | - | 2.09 | 1.21 | - | 2.39 | 2.61 | 5.26 | - | 1.09 | - | |
Dictyocha (Dictyochaceae) | - | - | 0.30 | - | 0.20 | - | - | - | - | - | ||
Gonyaulax (Gonyaulaceceae) | - | - | 9.57 | - | - | - | - | 6.75 | 0.40 | 1.75 | 0.62 | |
Dactyliosolen (Rhizosolenaceae) | - | - | 0.75 | 1.54 | - | - | 0.04 | - | - | - | - | - |
Thalassiothrix (Thalassionemataceae) | - | - | - | 3.62 | - | - | - | 2.12 | - | 0.21 | 2.78 | - |
Melosira (Melosiraceae) | - | - | - | 0.55 | - | - | - | - | - | - | - | - |
Eucampia (Biddulphiaceae) | - | - | - | 0.97 | - | - | - | - | - | - | 0.55 | 0.83 |
Leptocylindrus(Leptocylindraceae) | - | - | - | 1.29 | - | - | - | - | - | - | 0.40 | |
Diploneis (Diploneidaceae) | - | - | - | 0.44 | - | 0.11 | - | 0.44 | 0.48 | - | 0.54 | - |
Fragilariopsis (Fragilariaceae) | - | - | - | - | - | 0.31 | 0.75 | - | - | - | - | - |
Ampiphora (Amphiporidae) | - | - | - | - | - | 0.10 | - | - | - | - | - | - |
Meuniera(Stauroneisaceae) | - | - | - | - | - | 0.54 | - | - | - | - | - | - |
Haslea (Naviculaceae) | - | - | - | - | - | - | - | - | - | - | 3.40 | 1.24 |
Pronoctiluca (Noctilucaceae) | - | - | - | - | - | - | - | - | - | - | - | - |
Pyrocystis (Pyrocystaceae) | - | - | - | - | - | - | - | - | - | - | - | - |
Prorocentrum (Prorocentraceae) | 4.50 | 1.10 | 20.33 | 38.44 | 52.02 | 6.88 | 76.40 | 3.49 | 24.56 | 41.15 | 20.67 | 1.40 |
Ceratium (Ceratiaceae) | 1.50 | 0.52 | 14.50 | 10.14 | 14.53 | 0.46 | 1.56 | 15.82 | 8.20 | 27.80 | 18.42 | 6.54 |
Dinophysis (Dinophysiaceae) | 0.91 | 0.29 | 0.90 | 5.35 | 3.36 | 0.53 | 0.00 | 2.56 | 3.64 | 5.20 | 4.34 | 0.83 |
Total count (cells/ml) | 4.386 | 15.73 | 1.67 | 2.03 | 1.49 | 4.9 | 26.55 | 0.81 | 1.14 | 2.39 | 0.97 | 2.6 |
No. of family | 14 | 16 | 17 | 17 | 11 | 18 | 13 | 15 | 13 | 11 | 16 | 17 |
No. of genera | 15 | 19 | 18 | 20 | 12 | 20 | 15 | 18 | 14 | 13 | 18 | 20 |
NO 3 − | NO 2 − | PO4-P | NH3-N | Salinity | Temperature | pH | DO | TSS | Phytoplankton | |
---|---|---|---|---|---|---|---|---|---|---|
NO 3 − | 1 | 0.279 | 0.136 | 0.138 | 0.181 | −0.129 | −0.253 | 0.128 | 0.020 | 0.129 |
NO 2 − | 1 | 0.195 | −0.121 | 0.049 | 0.178 | −0.154 | −0.192 | −0.128 | 0.106 | |
PO4-P | 1 | 0.475* | −0.311 | 0.152 | −0.025 | −0.077 | −0.136 | 0.003 | ||
NH3-N | 1 | −0.517** | 0.001 | 0.261 | −0.239 | −0.011 | 0.237 | |||
Salinity | 1 | 0.020 | −0.157 | 0.505* | 0.408* | 0.040 | ||||
Temperature | 1 | 0.129 | 0.182 | 0.166 | −0.132 | |||||
pH | 1 | 0.257 | −0.098 | 0.157 | ||||||
DO | 1 | 0.451* | 0.162 | |||||||
TSS | 1 | 0.644** | ||||||||
Phytoplankton | 1 |
*Correlation is significant at the 0.05 level (2-tailed). **Correlation is significant at the 0.01 level (2-tailed).
is still in the beginning stage. However, the culture activity is expected to be expanding in the near future due to the considerable potential of the site, such as the availability of natural supply of bivalve spats (oysters and green mussel), and no major influence of water discharges from anthropogenic or industrial activities. At present, there are a few mariculture farms in the area, which mainly culturing mussel (green mussel and pacific oyster) and fish (grouper).
One of the important factors of site selection for bivalve farming is the availability and consistent supply of spats. Mussel and oyster culture in Sabah mainly relies on wild or natural spats. Once the spats settled, environmental conditions play important role in ensuring their growth and survival. For example, growth of green mussel is highly influenced by the food availability since it promotes sustainable growth [
Overall, water quality of the two sampling stations in Ambong Bay was shown suitable for green mussel culture, except for the phytoplankton composition, where the dominant phytoplankton, Prorocentrum spp., is one of the potential toxic algae or harmful algae species [
Fish farming is usually practiced in cages, where the site can be in open sea or coastal area. Due to the fact that fish does not have the ability to control their body temperature, sudden changes in temperature will affect their metabolic rate, oxygen consumption and as well as ammonia and carbon dioxide production [
Different species of fish have different tolerance towards water quality. In general, suitable water parameters for most tropical fish culture, according to [
The water quality in Ambong Bay is within the standard values permitted by the Malaysia Marine Water Quality Standard (Class 2) for pollution and suitability of seafood farming for human consumption. However, in order to have a thorough understanding on the suitability of the bay for profitable mariculture operation, studies on growth and survival performance of candidate species need to be conducted to determine their potential yield in relation to water quality, hydrodynamic properties, biological and microbiological components in the bay.
This study was financially supported by a research funding (NRGS0003) from the Ministry of Higher Education (MOHE), Malaysia.
Ong, F.S. and Ransangan, J. (2018) Assessment of Spatial and Temporal Variations of Water Quality for Future Mariculture Operation in Ambong Bay, Sabah, Malaysia. Open Journal of Marine Science, 8, 1-19. https://doi.org/10.4236/ojms.2018.81001