Write an MINI-REPORT about the OCEAN ACIDIFICATION PROJECT.

FANG 1

Ruoting Fang

ENVS& 101

August 14th 2019

Experiment Report

Along with the development of the world, human have created, however, they also have destroyed many at the same time. Exhaust gas from factories, carbon dioxide emissions from cars and human waste are all polluting the environment and destroying ecosystems. Many environmentalists are calling people’s attention to climate change, but more serious than climate change, it should be ocean acidification. The main reason for ocean acidification is the increase of atmospheric carbon dioxide, and more carbon dioxide enters the ocean, and a series of chemical reactions occur, which causes the pH value of seawater to drop. At the current rate of carbon emissions, the pH of seawater may fall to 7.8 in the future. At this pH, the corals completely stop growing and go extinct. Coral reefs are one of the largest ecosystems. As coral reefs disappear, fish that depend on coral ecology in shallow seas may become extinct. This can be seen as the humans have taken away the woods, the birds or some animals that depend on the woods are homeless and gradually become extinct. In order to understand the harm caused by ocean acidification to marine life, in this quarter, the experiment that we perform was putting a crab shell on the low PH sea water. In this experiment, The independent variable is PH of sea water, the dependent variable is crab shell, and the control variable is environment, temperature, time. We controlled crab shell, and the crab shell in sea water in the experiment.

Hypothesis: seawater acidification can cause softening of the crab shell.

Method: In the experiment, we simulate the change when carbon dioxide into the seawater, seawater PH value occurs. We put a certain amount of vinegar in a certain amount of seawater, which causes the pH value of seawater to drop. Then place the crab shell in the prepared seawater. We change the water every day to ensure a stable pH. We recorded the weight of the crab shell and the thickness of the crab shell within five days to conclude.

Result

In this experiment, we found that the longer the crab shell was soaked in vinegar-filled seawater, the smaller the weight and thickness of the crab shell. On the first day of recording, the weight of the crab shell was 58 grams, while its thickness was 0.3 cm. This was the state before the crab shell had not touched the sea. The next day after the crab shell was soaked, we took the crab shell and re-measured and recorded it. The weight of the crab shell was reduced by 0.14 grams, and the thickness was not thinned. On the third and fourth days, we found a significant reduction in the weight of the crab shell and a reduction in thickness of 0.18 cm. On the last day, we made the last record. Our team member accidentally crushed the crab shell. On the fifth day of the crab shell soaking, the crab shell became very soft and brittle. We could destroy the crab shell without any strength. Compared to the first day's record, the crab shell has changed greatly within five days.

From the analysis of the data and the observation, we had a conclusion. The acidification of seawater has caused softening of the crab shell, which confirms our conjecture. Today, the rate of ocean acidification has not stopped, which will seriously affect the marine ecological environment and the survival of marine organisms. Human should be know how serious that the issue is and start to reduce carbon dioxide emissions.