Science Project: Desalinization

I couldn't be prouder of the kid, he did a real science project. Here are the details and video of his science fair participation.

Background

If you’ve paid attention to current events, you probably know that there are many parts of the world without adequate access to water. One in nine people on Earth don’t have access to safe water, and one in three don’t have access to a toilet. Only 2.5% of Earth’s water is freshwater (water that we can use), and we only have access to 1% of Earth’s freshwater. This means that we rely on 0.00025% of Earth’s water to support billions (people?). Imagine if we could have access to more of Earth’s water. That’s exactly what my project will explore. Recently, a new idea known as water desalination has emerged; in which, usually ocean water has its salt removed in to make it accessible to us. But when the salt is removed it also removes all of the minerals in the water, creating pure water; just H 2 0. This is called distilling. But I wondered if distilled water could sustain life, because organisms also need minerals for different vital functions. My experiment was testing whether a plant could get adequate minerals from its soil in order to determine if desalinated water can be used on agriculture, which is an industry that is deeply affected by drought.

Question

Can a plant grow with pure water grow as much as or more than a plant that receives tap water or rain?

Hypothesis

If a plant is watered with distilled water, then it won’t grow as much as plants watered with rain and tap water, because they have more minerals for growth.

Research

First, I had to decide what plant to test. After researching this, I decided to do bean plants, due to the quick speeds that they grow at. My house doesn’t receive a lot of sunlight, so I purchased a grow light, and decided I would grow my plants inside. I learned that bean plants need about 4-6 inches of rain each week, so once every two days, I watered my plants with a dixie cup of water. I also realized that, in order to terminate flukes from my data, I would plant three plants for each water type.

Materials

● Soil

● 9 cups

● 1 dixie cup

● Bush bean seeds

● Grow light

● Tap water

● Distilled water

● Rain water

Procedure

I planted each bean one inch deep, every day, I turned on the grow light for about 12 hours, once every two days, I watered each plant with a dixie cup of the water that I was growing it with. Every day I record the height of the plants.

Conclusion

The results showed that distilled water produced two plants which had larger growth than others (15.75 inches and 13 inches). Given that one didn’t grow and one grew almost sixteen inches, we can’t conclude which water type is best, because we only used 3 plants per water type. The results of each water type varied significantly, so we can’t draw a conclusion on which type is best.

However we can conclude that distilled water can be effective for growing plants, because ⅔ of the distilled water plants grew to an above average height for this experiment (10.9 inches). Which shows that a plant doesn’t need minerals in water to effectively grow.

Future Directions

This is the first time I’ve grown bean plants, I could’ve done many things that would’ve helped or hindered growth such as: Too much or too little water or light, or I could’ve used the wrong soil, or any combination of those. In another experiment, it would’ve been more accurate to grow 100 of each, and have more controls, but my experiment answered my question.

The results show that farming communities struck by drought can use desalinated water to continue to grow their crops.