1.MANOL RIVER

In this activity, we learned about our rivers, its invader's species, how they affect our environment, why do they come, etc.

Material: River boots, fishing net and fish tanks.

Procedure: First of all, we have to put on our river boots and take the fishing nets.

Then, we go into the river and catch all the river creatures we see. As we take them, we put them on our fish tanks, so later, we can examinate the creatures we caught, and write it on our information sheet.

Conclusions: We came into a conclusion; Currently, there are more invasive species in rivers than native ones.

We also saw that some places of Catalonia had a big increase of invasive species, and some others barely changed.

Comparing with other oceans:

2.DETECTING CO2 IN RIVER WATER

Objectives: To visualise the presence of CO2 in the atmosphere.

Activity: The activity is to prove that CO2 is present in the atmosphere and is a reactive compound and is involved in atmospheric dynamics and climate regulation.

Materials: A beaker, two flasks, soda (NaOH), water, phenolphthalein, a container with a pierced lid or stopper, a thin plastic tube, a teaspoon, a pair of pipettes, silver foil, baking soda and vinegar.

Procedure:

1 - In a beaker, dissolve a lentil of caustic soda in about 50 ml of water.

2 - In two flasks, put about 100 ml of river water in each flask and add 10 drops of the sodium hydroxide (soda) solution that you have previously prepared.

3 - Add a drop of phenolphthalein to each flask (phenolphthalein, formula C20H14O4, is a pH indicator that remains colourless in acidic solutions, but in basic solutions it takes on a pinkish colour with a turning point between pH=8, 2 (colourless) and pH=10 (magenta or pinkish).

The solution in the flasks will take on a pink colour, which indicates that it has a pH higher than 8.2.

4 - Cover the mouth of one of the flasks with silver foil, which will serve as a reference.

5 - In an erlenmeier that we will have previously prepared by piercing the lid or the stopper and passing a small plastic tube through the hole, we will put vinegar and calcium bicarbonate. Quickly, we will cover it and put the other end of the tube that comes out of the container inside the flask that we have not covered with silver paper; the tube will make the gas that is generated (CO2) from inside the jar or bottle reach the solution that we have inside the flask. We will observe how the pink colour quickly disappears due to the sudden drop in pH when a large amount of CO2 enters.

Conclusions: The water of the river, which is in our village, is very polluted, the result came out with a dark green colour, which means that the level of contaminate is very high. This is due to climate change and the pollution of the area, the people who visit the river and leave their rubbish lying around, causing mini plastic particles to contaminate the river and its surroundings.

3.DETECTING CO2 IN RIVER SAND