Does Hydroponics with recycled water use more or less water than in irrigated agriculture in the soil?.

This experiment compares water use and growth in a hydroponic grower and a soil grower with no water recycle.

Build a hydroponic grower as in experiment 1.

Build a soil grower with a container like the hydroponic. Why would it be important that the containers are the same?_____________________

Cut a hole in the bottom of the soil grower and place on support with a glass container under the hole. This glass should be big enough to catch the excess water.

Plant beans in each grower.

Each day, water each of the growers. For the hydroponic grower, use recycled water from the nutrient water tank.

1. use a measuring cup or other measuring device so you can keep track of how much water is poured into the grower.
2. Keep track of the number of cups poured.
3. Catch the excess water that drain from the hydroponic grower. When the grower quits draining measure the excess water. Record this number on the data sheet.
4. Subtract the excess water from the total water poured to determine how much water was used by the plant.

Soil Grower

5. Measure out clean water and pour the same amount of water used by the hydroponic plant into the soil grower. Allow the excess to drain into the glass below.
6. When the soil grower has finished draining, measure the excess water in the glass below. Since soil crops do not recycle water, the water is used on grass outside or plants. It should not be put down a drain because it could clog the drain. Notice a problem with a non-recycle system is what to do with the waste water.

When recording data, the water that was drained out of the soil grower represents the amount of extra water used by the soil grower. It represents the amount of water that would drain from the soil and not used by the plant. The color or dirt in the water represents nutrients that would be lost by a system without recycle.