Theoretical Framework

Procedural Framework

Procedural Framework

Procedural Framework

The objective of this research is to systematically assess three distinct methodologies namely Analytical testing, Winkler, and PASCO method, for the effective measurement of dissolved oxygen present in bodies of water. A thorough and comprehensive study must identify its focus, purpose, and the variables that are involved. Wherein researchers ascertain the study's focal point, purpose, and the variables under consideration. Moreover, meticulous organization of acquired data is crucial as it avoids inaccuracies and thus, gives accurate conclusions.

By using a z-test with the results, the research aims to evaluate if any of the methods, namely Winkler and PASCO, has significant differences to Analytical testing. The data will have values such as 2.41 as the null hypothesis, which represents the standard or Analytical testing. A level of significance of 0.05, and left-tailed test which resulted in a critical value of -1.645. The value of n is 3 as it represents the number of water samples and testing methods involved. And in addition, with a standard deviation of 1.5. Using the z-test formula, the study came with a result of Winkler having a value of -0.81 and PASCO with a value of -2.32. 

Since the critical value is -1.645, Winkler is not within its critical range, thus it is acceptable and does not have enough evidence to reject the null hypothesis. While the PASCO method exceeded the critical range, and can be said to have a significant difference. Therefore, it concludes that the Winkler method is a much more reliable and effective method based on the given results and in comparison to the PASCO method. In addition to this, given the Winkler method’s value it does not have significant differences with Analytical testing.

However, the PASCO went beyond the accepted value as its value was -2.32 meaning the null hypothesis is rejected and has a significant difference. Additionally, since the Winkler’s value is accepted it can not be said that it has a significant difference to the Analytical testing value. This research could conclude that it was able to give its objective; Winkler method being the most effective method in measuring dissolved oxygen and in comparison with the other methods.

Before conducting the study, the researchers had knowledge about the possible factors that may influence and affect the amount of dissolved oxygen present in the body of water. Moreover, research findings related to both methods, Winkler and PASCO, were not sufficient enough hence, the study was conducted by relying on related literatures. Hence, it was observed by the researchers that even though the analytical testing and Winkler Method were conducted within the same time period, there was a significant gap between the two measured data, while the results for the PASCO method was expected since it was conducted within a different time period. 

Furthermore, the measured amount of dissolved oxygen compared to the ideal amount of dissolved oxygen ranging from 6.5mg/L to 8mg/L was very far. With this, though the Manila Bay had gone through several rehabilitation and reclamation projects, it did not have significant results in terms of increasing the habitability, and potability of the water sample taking into consideration that establishments and communities rely on the tested body of water.

The results show that the WINKLER method is a more effective method when it comes to determining the amount of Dissolved Oxygen in water. The research is about finding out which method is more accurate in determining the amount of dissolved oxygen in water. There are three (3) existing methods; Analytical testing, the WINKLER method, and the PASCO method which have been all tested by the researchers in order to determine their accuracy and compare the given results with one another.

This year the researchers used a more statistical approach with their research which is also known as Quantitative research. While in their previous in-field experience the researchers used a more approachable approach with their research by simply selecting a few participants in their research, this may also be known as a Qualitative research approach. Compared to other research existing this research tackles more about the accuracy of the three methods used. The study is more of a comparative study in knowing which type of method is more accurate in determining the amount of dissolved oxygen in water, this could help society with determining which method is more safe and accurate to use.

The importance of dissolved oxygen to all life forms plays a critical role in survival, without properly testing the accuracy of water it will put everyone’s life at risk. The results from this experiment add knowledge to both science and biology, giving information on which method could be trusted more or how to determine the accuracy of the dissolved oxygen in water. This research contributes to the knowledge of dissolved oxygen given the lack of study on the said topic. Lack of study mentioned, comparative studies about these methods are rare to find and lack further observation. This may affect the researchers' study between analytical, Winkler, and PASCO methods but for now, it is safe to say that the Winkler method is the most safest and accurate method to use.

Based on the gathered data and interpreted results, the researchers determined that the Winkler method is more accurate in measuring the dissolved oxygen levels due to how close its results are to the data obtained from the analytical testing, as well as the computed results after conducting a z-test which indicates that any value that exceeds the criterion of -1.645 will be rejected. This is because the Winkler method’s value of -0.81 is in the accepted region, whereas the PASCO’s value of -2.32 is in the rejected region as it is beyond the critical value. Moreover, the measured data of 2.41mg/L of dissolved oxygen present in the water sample from Manila Bay fell outside the ideal criterion range of 6.5 - 9 mg/L, suggesting suboptimal DO levels. 

The study noted that various external factors contributed to the discrepancy of measured values as previously stated in the research paper. Consequently, the research implies that there is insufficient protection from external factors due to the lack of support in protecting the waters from both the residents and the local government. Hence, the researchers suggest that in re-conducting the experiment, each set-up shall be conducted within the same time frame, and the materials and set-ups shall be prepared and calibrated ahead of time, as well as gathering more sample water from locations connected to Manila Bay.