Coral Reef Guardians

Overview

A coral reef is an underwater world made by corals that build reefs. These reefs are made up of many tiny coral animals called polyps. They stick together with a hard white stuff called calcium carbonate. These reefs are crucial habitats for over 4,000 fish species, earning them the nickname "rainforests of the sea." They provide shelter, food, and breeding grounds for marine life. Additionally, coral reefs protect coastlines from erosion and storms, and attract tourists to over 100 countries and territories.

Coral bleaching occurs when corals turn white due to stress, often from warmer ocean temperatures. This causes them to expel the colorful algae that provide their color and energy. Without the algae, corals weaken and are more likely to die. Coral reefs, home to many marine species, provide food and shelter. If corals die, these species lose their habitat and may also die. Reefs also protect coasts from erosion and storms, but bleaching weakens this protection, making coastal areas more vulnerable.

Today, we will build our own coral reef model and simulate the process of coral bleaching to learn about the causes of coral bleaching and what we can do to prevent coral reefs from bleaching.

Standards

NGSS-NEXT GENERATION SCIENCE STANDARDS-MIDDLE SCHOOL(MS)

Engineering Design
Life Science

The national curriculum in England

Subject content -Science
Living things and their habitats
recognize that environments can change and that this can sometimes pose dangers to living things.

Materials

Activity

1.Connection

Connect the sensors as shown in the picture below.

Connect the micro:bit to the computer.

2.Experiment One:Construct a Coral Reef Model

(1)Get to Know RGB LED Strip

The RGB LED strip is composed of 7 colored LEDs.LED is capable of emitting three primary colors: red, green, and blue, commonly referred to as RGB. By adjusting the brightness of the red, green, and blue lights in each LED, a wide range of colors can be produced.

(2)Using Blocks to Build Coral Reef Model

We use LED strips and building blocks to make a coral model. First, we construct a base to secure the LED strips. Please build the base according to the following illustration.

After that, we can build the shape of a coral reef on the base using building blocks. You can use your imagination and make it as you like.

(3)Light up the LED Strip

In order to make the coral model more realistic, next, we will write code to light up the LED strip in red.
Open the programming website;https://makecode.microbit.org/.
Create a project named : coral reef guardians

Click  ' Extensions ' to load the extensions library - Boson.

Next, we will write a program to light up the LED strip, making the coral reef model glow red. Step one: Initialize the LED strip and set the brightness to 255. 255 is the maximum brightness of the LED strip.

Next, set all the LEDs to full red, as shown in the picture below.

Click the 'Download' to download the code into micro:bit. After successfully uploading code, observe the coral reef model that has turned red.

(4)Change the LED Strip from Red to White

Next, let's write the code to change the LED strip from red to white to simulate the process of coral bleaching.The color of the LED strip is controlled by RGB values. RGB stands for Red, Green, and Blue. These are the three primary colors of light that can be combined in different ways to create a wide range of colors.

For the red color, RGB is (255,0,0).. When we want the LED strip to display white, RGB is (255,255,255).Writing the code to transition the RGB values from (255, 0, 0) for red to (255, 255, 255) for white, we can visually simulate the coral bleaching process, where the coral loses its vibrant colors and appears white.

First, we create a variable i.

Write the following code to gradually increase the values of green and blue by incrementally increasing the value of the variable i, causing the LED strip to transition from red to white, thereby simulating the process of coral bleaching.

(5)Observe the Running Effect

Click the 'download' button.After the code is successfully uploaded, observe the actual effect.As shown in the figure.The LED strip gradually changes from red to white to simulate coral reef bleaching.

3.Experiment Two:Investigating the Causes of Bleaching

Please find information, summarize the factors of coral bleaching, and complete the following table.

In general, coral bleaching is caused by a variety of factors, such as rising sea water temperature, ocean acidification, overfishing, and sea water pollution. Among them, the rise in sea water temperature caused by global warming is the main reason for coral bleaching.
Next, we will use waterproof temperature sensor and light sensor to simulate the process of coral bleaching caused by temperature increase.

Next, we will use waterproof temperature sensor and light sensor to simulate the process of coral bleaching caused by temperature increase.

(1)Get to Know Waterproof Temperature Sensor 

The waterproof temperature sensor is a temperature sensor that is resistant to water. In environments with relatively high humidity, this sensor can play an extremely important role.

(2)Read Temperature and Light

Next, we will use a waterproof temperature sensor and a light sensor to simulate the reading of ocean temperature and light, and display the data on an OLED screen.
Continue programming based on the code of Experiment 1.Create new variables, one named "temp" and the other named "light".

Before reading data, we need to complete the initialization of the OLED Display module first. Please follow the tutorial below to complete the initialization.

Use the following code to read the water temperature and light separately, and assign them to the variables 'temp'and 'light', respectively.And display the temperature and light on the first and third lines of the OLED screen, respectively.

(3)Observe the Running Effect                                                                                                                    

Click the download button and then watch the screen of OLED Display module.You can see that the current temperature and light intensity are displayed on the screen of the OLED display module and are constantly updating.

(4)Simulate the Process of Coral Reef Bleaching

Through the following picture, we can learn that when the sea water temperature exceeds 29  degrees Celsius , it will cause the coral reefs turning white due to the loss of symbiotic zooxanthellae. Next, we will write a program so that when the waterproof temperature sensor reads a temperature greater than 29 degrees Celsius, the LED strip will gradually change from red to white, simulating the bleaching of coral reefs due to rising temperature.

Use conditional statements. If the water temperature is greater than 29 degrees Celsius, the LED strip will gradually change from red to white. Otherwise, the LED strip will remain red.

The complete program is shown in the following figure.
The program link:https://makecode.microbit.org/_7CWeH7fk00M8

Building

Disconnect the micro:bit from the computer.Connect the Boson micro:bit mainboard and Battery holder.

Install the sensors in the corresponding position on the kit board, add water to the cup, and place the probe of the waterproof temperature sensor into the cup.
 

The final product is as shown in the figure below.

Observation

Congratulations! You have successfully created a coral reef model and can observe the phenomenon of coral bleaching through the model. Next, let's watch the effect video together.

What can we do to prevent coral bleaching? I have collected the following actions. Please help me determine which of these actions are correct and check the correct ones.