> × ( c 1 )

$\left(2-1\right)×\left(3-1\right)=2$

${E}_{r,c}=\frac{{n}_{r}×{n}_{c}}{n}$

Table 1. Response to hypothesis I to VII.

${E}_{1,1}={E}_{1,2}={E}_{1,3}=\frac{161×60}{180}=53.66$ (8)

${E}_{2,1}={E}_{2,2}={E}_{2,3}=\frac{19×60}{180}=6.33$ (9)

${X}_{c}^{2}=\sum \left[\frac{{\left({O}_{r,c}-{E}_{r,c}\right)}^{2}}{{E}_{r,c}}\right]$ $\therefore {X}_{c}^{2}=8.562$ (10)

3) Marine pollution does not affect fishing activities. The research question shows that fishing activity can affect the pollution of the marine environment.

$DF=\left(r-1\right)×\left(c-1\right)$

$\left(2-1\right)×\left(3-1\right)=2$

${E}_{r,c}=\frac{{n}_{r}×{n}_{c}}{n}$

${E}_{1,1}={E}_{1,2}={E}_{1,3}=\frac{164×60}{180}=54.66$ (11)

${E}_{2,1}={E}_{2,2}={E}_{2,3}=\frac{16×60}{180}=5.33$ (12)

${X}_{c}^{2}=\sum \left[\frac{{\left({O}_{r,c}-{E}_{r,c}\right)}^{2}}{{E}_{r,c}}\right]$ ${X}_{c}^{2}=10.00$ (13)

4) Ship sewage treatment do not control the amount of bacteria discharged into water bodies. The research question shows that ship sewage treatment help to control the amount of bacteria discharged into water bodies.

$DF=\left(r-1\right)×\left(c-1\right)$

$\left(2-1\right)×\left(3-1\right)=2$

${E}_{r,c}=\frac{{n}_{r}×{n}_{c}}{n}$

${E}_{1,1}={E}_{1,2}={E}_{1,3}=\frac{146×60}{180}=48.66$ (14)

${E}_{2,1}={E}_{2,2}={E}_{2,3}=\frac{34×60}{180}=11.33$ (15)

${X}_{c}^{2}=\sum \left[\frac{{\left({O}_{r,c}-{E}_{r,c}\right)}^{2}}{{E}_{r,c}}\right]$ ${X}_{c}^{2}=7.453$ (16)

5) Failure to comply with IMO regulations have not contributed to pollution of Nigeria waterways. The research question shows that disobedience to IMO regulations contribute to pollution of Nigeria waterways.

$DF=\left(r-1\right)×\left(c-1\right)$

$\left(2-1\right)×\left(3-1\right)=2$

${E}_{r,c}=\frac{{n}_{r}×{n}_{c}}{n}$

${E}_{1,1}={E}_{1,2}={E}_{1,3}=\frac{147×60}{180}=49$ (17)

${E}_{2,1}={E}_{2,2}={E}_{2,3}=\frac{33×60}{180}=11$ (18)

${X}_{c}^{2}=\sum \left[\frac{{\left({O}_{r,c}-{E}_{r,c}\right)}^{2}}{{E}_{r,c}}\right]$ ${X}_{c}^{2}=11.55$ (19)

6) Marine pollution does not affect the immune and endocrine systems of humans. The research question shows that the human immune and endocrine system can be affect by marine pollution.

$DF=\left(r-1\right)×\left(c-1\right)$

$\left(2-1\right)×\left(3-1\right)=2$

${E}_{r,c}=\frac{{n}_{r}×{n}_{c}}{n}$

${E}_{1,1}={E}_{1,2}={E}_{1,3}=\frac{81×60}{180}=27$ (20)

${E}_{2,1}={E}_{2,2}={E}_{2,3}=\frac{99×60}{180}=33$ (21)

${X}_{c}^{2}=\sum \left[\frac{{\left({O}_{r,c}-{E}_{r,c}\right)}^{2}}{{E}_{r,c}}\right]$ ${X}_{c}^{2}=9.81$ (22)

7) Oil spill is not the most common source of marine pollution. The research question shows that oil spill is the most common source of marine pollution.

$DF=\left(r-1\right)×\left(c-1\right)$

$\left(2-1\right)×\left(3-1\right)=2$

${E}_{r,c}=\frac{{n}_{r}×{n}_{c}}{n}$

${E}_{1,1}={E}_{1,2}={E}_{1,3}=\frac{128×60}{180}=42.66$ (23)

${E}_{2,1}={E}_{2,2}={E}_{2,3}=\frac{52×60}{180}=17.33$ (24)

${X}_{c}^{2}=\sum \left[\frac{{\left({O}_{r,c}-{E}_{r,c}\right)}^{2}}{{E}_{r,c}}\right]$ ${X}_{c}^{2}=8.00$ (25)

5. Results and Discussion

Table 2 and Table 3 show the comparison of the observed and expected and the Social-Economic information of staff of Onne, Okrika and Port Harcourt

Table 2. Comparison of the observed and expected response (Hypothesis I to VII).

Table 3. Social-Economic information of staffs of Onne, Okrika and Port Harcourt port.

port respectively. From Figure 7, the category with the largest difference between observed and expected value makes the largest contribution to the overall chi-square statistic. In this case, the largest contribution comes from Port Harcourt port. At significance level of 5% that is 0.05, using chi-square probability calculator-formula. Inputting values of ${X}_{c}^{2}=9.15$ and DF = 2, P-value = 0.0103. Since the P-value is less than the level of significance (0.0103 < 0.05), we reject the null hypothesis. Hence, we conclude that there is awareness of the existence of IMO. Similarly Figure 8 shows that the largest contribution comes from Onne port. At significance level of 5% that is 0.05, using chi-square probability calculator-formula. Inputting values of ${X}_{c}^{2}=8.562$ and DF = 2, P-value = 0.0138. Since the P-value is less than the level of significance (0.0138 < 0.05), we reject the null hypothesis. Hence, we conclude that untreated wastewater discharge from ship causes pollution of the marine environment.

Similarly Figure 9 shows the largest contribution comes from Okrika jetty. At significance level of 5% that is 0.05, using chi-square probability calculator- formula. Inputting values of ${X}_{c}^{2}=10.00$ and DF = 2, P-value = 0.0067. Since the P-value is less than the level of significance (0.0067 < 0.05), we reject the null hypothesis. Hence, we conclude that marine pollution causes hindrance in fishing activities. Furthermore Figure 10 shows that the largest contribution comes

Figure 7. Observed and expected value for H-1.

Figure 8. Observed and expected value for H-II.

Figure 9. Observed and expected value for H-III.

from Port Harcourt port. At significance level of 5% that is 0.05, using chi- square probability calculator-formula. Inputting values of ${X}_{c}^{2}=7.453$ and DF = 2, P-value = 0.0240. Since the P-value is less than the level of significance (0.0240 < 0.05), we reject the null hypothesis. Thus, we conclude that ship sewage treatment help to control the amount of bacteria discharged into water bodies.

Figure 11 shows that the largest contribution comes from Okrika jetty. At significance level of 5% that is 0.05, using chi-square probability calculator-formula. Inputting values of ${X}_{c}^{2}=11.55$ and DF = 2, P-value = 0.0031. Since the P-value is less than the level of significance (0.0031 < 0.05), we reject the null hypothesis. Thus, we conclude that failure to comply with IMO regulations have contributed to pollution of Nigeria waterways. Similarly from Figure 12, the largest contribution comes from Okrika jetty. At significance level of 5% that is 0.05, using chi-square probability calculator-formula. Inputting values of ${X}_{c}^{2}=8.00$ and DF = 2, P-value = 0.0074. Since the P-value is less than the level of significance (0.0074 < 0.05), we reject the null hypothesis. Thus, we conclude

Figure 10. Observed and expected value for H-1V.

Figure 11. Observed and expected value for H-V.

Figure 12. Observed and expected value for H-VI.

that marine pollution affects the immune and endocrine system of humans.

Figure 13 shows the largest contribution comes from Port Harcourt port. At significance level of 5% that is 0.05, using chi-square probability calculator- formula. Inputting values of ${X}_{c}^{2}=8.00$ and DF = 2, P-value = 0.0183. Since the P-value is less than the level of significance (0.0183 < 0.05), we reject the null hypothesis. Thus, we conclude that oil spill is the most common source of marine pollution.

SALINITY AND pH

The salinity and pH of the water sample from the Onne port were analyzed with HANNA MULTIPARAMETER EQUIPMENT. This involves standardizing the equipment with solutions that were bought with the equipment, cleaning the probes very well with distilled water after standardizing, dipping the probe in the sample collected in a beaker and taking the necessary reading as displayed on the screen. Table 4 shows the result of the analysis.

SALINITY: Salinity is a measure of how much dissolved salts are in the water. Dissolved salts are usually sodium and chloride ions, although there can also be many others such as potassium and bicarbonate ions. Salinity can vary during the year due to rain diluting the salt in the water. Therefore, high salinity is usually recorded in the summer and low salinity in the winter. As a general rule, salinity is relatively low during periods of high flow and vice-versa. Table 5 shows the salinity ranges from fresh to hyper-saline.

From the table, it is seen that the test result falls within 5000 to 35,000 (mg/L). It is concluded that Onne water is salty and safe.

Figure 13. Observed and expected value for H-VII.

Table 4. Result of sample analysis.

Table 5. Ranges of salinity in water.

TURBIDITY: Turbidity is the cloudiness or haziness of a fluid caused by individual particles that are generally invisible to the naked eye. The lower the value, the clearer the water is. At no time should the turbidity go above 5 Nephelolometric Turbidity Unit (NTU).

pH: Seawater is naturally alkaline, with an average pH of 7.6. The normal pH range for seawater is 7.2 - 8.4. The pH of seawater is lower around river mouths. BOD5: Biochemical oxygen demand (BOD) measures the uptake rate of dissolved oxygen by the biological organisms in a body of water. The higher the pH level of the water the lesser the quality of water. Most pristine seawater will have a 5-day carbonaceous BOD below 1 mg/L. Moderately polluted rivers may have a BOD value in the range of 2 to 8 mg/L. Municipal sewage that is efficiently treated by a three-stage process would have a value of about 20 mg/L or less

TPH: The level Total Petroleum Hydrocarbon (TPH) was found to be 2.98 (mg/l). Since all conditions of sampling and sample preservations were observed and the value is less than the DPR limit (10mg/l), it then means that the activities in Onne port is adhering to standard and the environment is not being polluted.

6. Conclusion

In conclusion, it is a fact that marine pollution will severely affect the coastal resources of a city, state and the nation, so it should be avoided. This can be done by obeying the rules and regulations setup by national and international organization concerned with the environment especially the maritime environment. It is a thing of joy to see and know that after proper analysis of the water sample from Onne port the environment is considered safe within the regulatory framework of IMO. It is true that when an environment is not safe, it could endanger the future stability of human health and risk the aquatic life of the fast growing cities like Port Harcourt, Onne and Okrika in Nigeria. The challenges posed by marine pollution from ports on human health, aquatic lives and the environment in general have not yet received full attention which it deserves. The surveys carried out in this work show the sources of marine pollution from ships which have been established to be the discharge of oily water from bilge, invasive organisms from ballast, accidental discharge of oil from tankers ships and operational discharge and so on. The industries around the ports or jetty could also contribute to the pollution of the maritime environment by releasing harmful chemical into the sea. The adverse effects of introducing pollutants into the marine environment have also been established in this work. The effects appear to be damaging to the ecosystem, ships life and human health. Control and preventive measures have been established which include adherence and enforcement of standard operations as contained in ANNEX I-VI of IMO conventions. From the result so far, we can say Onne port is operating within the safe limit of IMO regulation and should endeavor to maintain this trend. However, there is need for proper implementation of the maritime regulations in Nigerian waterways. We recommend aggressive implementation of the existing laws, policies and guidelines on port pollution by relevant local and International organization. The government should punish any erring organization or individuals to serve as a deterrent to others, government should encourage and support relevant law enforcement agencies assigned with such duties. This will address the problem of environmental pollution and bring about sustainable urban development in Rivers State in particular and Nigeria in general.

Conflicts of Interest

The authors declare no conflicts of interest.

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