Geog Field Trip to ECP (Research + Reflection) -Jiayu

Hypothesis:

- The seawater at East Coast is polluted and is acidic.

What we need to find out:

- The clarity of the seawater

- Whether the seawater is acidic or alkaline

- Type of dirt particles or rubbish in the seawater

- Photographs evidence of polluted water

Methodology:

1. Walk along East Coast Beach and identify 4 points along the sea with different activities going on.

2. Collect a sample (1 bottle) of seawater from each sample.

3. Label point A, B, C or D on the bottles.

4. Pour out 2 beakers of 50cm3 of seawater from each sample

5. Observe the clarity of the seawater and smell it. Record down observations.

6. Pour out some seawater from each sample into different test tubes.

7. Dip red and blue litmus paper into the seawater in each test tube then record observations.

8. Drop pH paper into the test tube and record the pH.

9. Filter one of the 2 beakers of seawater from each sample then boil it in an evaporating dish until the salt is left. Record observations and time.

10. With the other beaker left, boil it straight in an evaporating dish without filtering, until the salt is left. Record observations ad time.

11. Compare the results for the different samples.

 

Findings

(1) MOST -------(4) LEAST

Samples:

Point A: Tents, Camping , a lot of ships, more people, human activities, rubbish on shore

Point B: Less human activities, more birds, hardly any rubbish

Point C: Strong waves, A lot of rubbish, Left of the jetty

Point D: Hardly any rubbish, smaller waves than left side of the jetty

Observation:

Point A: No smell, slightly cloudy

Point B: No smell, slightly cloudy

Point C: Strong fishy smell, slightly cloudy

Point D: Fishy smell, slightly cloudy

 

Observations during the boiling of the water (filtered):

Bottle A: A lot of effervescence is produced.

Bottle B: A lot of effervescence is produced.

Bottle C: Little effervescence is produced.

Bottle D: A lot of effervescence is produced.

Observations during the boiling of the water (unfiltered):

Bottle A: A lot of effervescence is produced.

Bottle B: A lot of effervescence is produced.

Bottle C: Hardly any effervescence is produced.

Bottle D: A lot of effervescence is produced.

 

Litmus paper test & pH Paper test

pH for all samples: pH 9

 

Bottle A (top left hand corner): turned red litmus paper slightly blue. Blue litmus paper remains blue.

Bottle B (bottom left hand corner): turned red litmus paper slightly blue. Blue litmus paper remains blue.

Bottle C (top right hand corner): turned red litmus paper slightly blue. Blue litmus paper remains blue.

Bottle D (bottom right hand corner): turned red litmus paper slightly blue. Blue litmus paper remains blue.

 

 

Filtration Test:

 

Amount of Residue:

Point A: (1)Most Residue

Point B: (2) Lots of Residue                              

Point C: (3) A little Residue

Point D: (4) Hardly any Residue

 

Boiling Test:

Boiling of the seawater that is not filtered

Amount of salt:

A: (3)

B: (2)

C: (4)

D: (1)

Time taken:

A: 15:11 mins

B: 12:58 mins  

C: 18:05 mins

D: 10:54 mins

Boiling of the seawater that is filtered

Amount of salt:

A: (3)

B: (2)

C: (4)

D: (1)

Time taken:

A: 11:55 mins

B: 10:57 mins

C: 13:09 mins

D: 12:33 mins 

Reflection:

Through this field trip, i have understood more about the clarity of seawater and its pH level

 

I found out that seawater is actually alkali, opposite of what we have expected. I also found out that the seawater is different at different parts of the sea due to the activities conducted there. For example, the seawater near the jetty smells like fish as fishing activities are carried out there. Another example is that the sea water does not smell fishy in areas where human activities are  kept to the minimum. The water is also much clearer at points A & B than points C & D. This is because points A & B does not allow people to swim there and points C&D are near the jetty, where there are more human activities and fishes around.

The reason why there are more rubbish at the left side of the jetty than the right side of the jetty is because waves move from right to left. When the waves high  the jetty walls, it loses energy thus resulting in the rubbish depositing at the left side of the jetty. However, as the water continues to move on to the right side of the jetty, a process called erosion is taken place there. This is why there are more rubbish at the left side of the jetty and the shore seem to be higher and cleaner at the right side of the jetty.

Points C&D are most likely to be more chemically polluted than physically polluted as the samples from those 2 points took the longest to evaporate. When the sample from point C was boiling, hardly any effervescence was found. With the filtration test,  the residues found on the filter paper is the least therefore this shows that the seawater at points C&D Is not suitable for swimming as it may cause skin diseases.

Overall, the seawater at East coast park is quite polluted.

-Jiayu