Research Article Open Access

The impact of simulated nitric and sulfuric acid precipitation on five North American dandelion growth parameters

Abstract

Acid precipitation is a prevailing environmental problem caused by many man- made and naturally occurring processes. Growth characteristics of the North American dandelion (Taraxacum officinale) were analyzed after 8 weeks of exposure to either distilled water, simulated rainwater (pH 5.6) or simulated nitric, sulfuric, and hydrochloric acid rain at pH 4.4 and 4.2. Statistical analyses determined that acid treatment (HNO3, H2SO4, or HCL) as well was pH (4.2, 4.4, 5.6, or 7.0) of the treatment had significant effects on number of leaves produced, longest leaf length, and leaf dry mass. Additionally, two-way interaction effects between acid treatment showed that plants exposed to H2SO4 at pH 4.4 produced more leaves, had a higher mean leaf mass and higher total plant biomass than plants produced in other pH 4.4 treatment groups. HNO3 pH 4.2 treatment plants produced more leaves, had higher mean leaf, root, and total plant biomass than plants grown with different acid treatments at pH 4.2. Finally, dandelions treated with HCl pH 4.2 and pH 4.4 produced the longest living leaves compared to other pH and acid treatment combinations. These results demonstrate that in most circumstances dandelions treated with low pH acid solution (4.2 and 4.4) appear to outperform those treated with distilled (pH 7.0) or rainwater (pH 5.6). In addition, no visible morphological effects, such as necrosis or chlorosis were observed in plants treated with any of the simulated acid precipitation treatments while growing in the greenhouse for the duration of the study. It is possible that these results are in part due to safety mechanisms many plants possess to physiologically minimize damage arising from environmental stress, thus allowing them to survive when conditions are unfavorable.

Julianna S Fisher¹, Emma R Barnhart², Matthew H Collier^3*

To read the full article Download Full Article | Visit Full Article