Candee's 'Salt of the Earth'

Does a higher salt concentration in water affect a plant’s growth? That is what Sidney Middle School student, Justin Candee, took a look into for his science fair project this year.

The amount of salt greatly affects the amount of absorption. You would think that the less the salt, the less water you need which will in turn lead to more growth. That is exactly what Candee set out to find out.

The accumulation of salt in the soil can happen both naturally and due to humans. The natural processes deposit salt by weathering down parent materials releasing their soluble salts and wind and rain carrying oceanic salt. Humans can introduce excess salt into the soil by using irrigation water that may be high in salinity, as well has insufficient drainage. Both of these incidents cause the water table to rise up bringing the salts up from the sub-soil. As Candee very scientifically stated in his project, “Human induced salinity is caused by human activities that change the hydrological balance of the soil between water applied and water used by crops.”

To discover the best salinity content for plant growth, Candee researched to find a plant that is sensitive to salt that would give a better result in a shorter amount of time. As in any experiment, Candee was precise with the amount of soil, amount of water, amount of sunlight, and placement of the seed in each instance. The only variable was the amount of salinity in the water including groups with no salt, .41 grams, 2 grams and 4 grams.

Over a span of 41 days, Candee watered each plant with a quarter cup of water whenever it would dry up to an inch deep. Throughout the growing process, he measured and photographed each plant on the same days.

With his hypothesis that the higher salt concentration the less the growth, Candee was kind of surprised to find that that was not the case. “I expected the no salt,” stated Candee. In fact, his findings showed that the plants with .41 grams of salt grew taller at 8.65 centimeters, with the no salt following close behind at 8.3 centimeters. When the salinity is high, it absorbs the water and nutrients needed for plants to thrive. This was evident with the plants that received 2 and 4 grams, as they wilted near the end of the experiment at 7.55 and 6.75 centimeters respectively.

Although he took First Place for the 8th Grade, Candee feels it could have gone better. He feels that he could have checked the growth more consistently, but the watering system worked out well.

Candee chose this topic because it is a real problem for farmers, and feels his results will be useful to farmers around the area.