The effect of nitrate levels in water on the growth of plants
The hypothesis that watering mung bean plants with water containing nitrates will help them grow more quickly is proven to be true only to a certain extent. The plants grew more quickly with 0.1% nitrate solution (pot B). The growth rate fell in the other pots indicating an overdose of nitrates.
The excessive use of nitrate based fertilizers can cause nitrate to leak into our drinking waters. Levels of nitrates above 10ppm in drinking water is known to cause health problems. Nitrate leakage into ponds will increase the levels of ammonia, which is toxic to fishes.
Consider repeating this science fair project to study how fishes are able to survive in water containing nitrates?
The science project experiment can be repeated to compare the growth of different types of plants.
Nitrate in soils and plants - http://extension.missouri.edu/publications/DisplayPub.aspx?P=G9804
Water quality and nitrates & phosphates - http://www.ncsu.edu/sciencejunction/depot/science fair projects/water/lessons/np/
Level of nitrogen vs. plant growth - http://www.selah.k12.wa.us/SOAR/SciProj2000/MorgenA.html
Basic safety requirements