Negative Effects of Pollution on English Daisy (Bellis perennis) Height and Flower Number
(1) Maria Carrillo High School, Santa Rosa, California, (2) Bodega Marine Lab, University of California - Davis, Bodega Bay, California
River pollution is an increasingly serious issue that can lead to an imbalance in an ecosystem. Chemicals found in fertilizers and pesticides, such as phosphate and nitrogen, often end up in nearby water and can have a negative effect on surrounding plant life. In this experiment, we assessed the effect of water containing different nitrogen levels on the height and number of mature flowers of the English daisy (Bellis perennis). We compared English daisy plants exposed to water with high levels of added nitrogen (representing high pollution), low levels of added nitrogen (representing low pollution), and tap water. The high pollution treatment caused plants to decrease in height over three weeks. Plants in the low pollution treatment increased in height the first week, but then decreased during weeks two and three. The plants treated with tap water stayed fairly constant in height during the experiment. There was a small increase in the number of mature flowers in the low pollution treatment, while the plants exposed to the high pollution treatment and tap water treatment both lost similar numbers of flowers. This indicates that there is a negative effect of pollution on plant height and an inconclusive effect on number of mature flowers. Further studies, including beginning plants from seedlings and investigating the effects of different chemical pollutants, are needed to determine the full effect of water pollution on the English daisy.