Aquatic and Terrestrial Plant Species with Potential to Remove Heavy Metals from Stormwater By: Asa Fritioff & Maria Greger Department of Botany Stockholm University Source: International Journal of Phytoremediation Date Published: May 3rd, 2003 Presenter: Gianna Grabowski
Thesis & Importance of Article • Percolation systems or wetlands contain plant species that are capable of phtyoremediating stormwater contaminated with heavy metals. • The most toxic metals commonly found in stormwater were used in this study, including cadmium, copper, zinc, and lead.
Important Terms • Stormwater= is where impervious surfaces, such as roads and roofs, drain rain and snow melt water. It is mostly contaminated by organic pollutants, oil, and heavy metals, • Phytoremediation= is a process where contamination is either stabilized, eliminated, removed, or destroyed by plants.
Background • Heavy metal concentrations are usually greater in stormwater than in naturally occurring waters. • Wetland/percolation area treatment of stormwater is preferable over other methods. • Contaminated areas contain a variety of plant species with differing capabilities for heavy metal remediation.
Background Continued • Terrestrial and emergent plant species exist in percolation areas. • Free-floating, submerged, and emergent plants occur in wetlands. • The most effective metal remediating plants were needed for this study. • To determine this, a metal concentration analysis was done on the most common plants found in the study area.
Methods- Field Study • Three sampling areas were used for the field experiment, labeled Areas 1, 2, and 3. • They were all located 7-15 km south of Stockholm, Sweden. • Plants and soil samples were taken from all 3 areas on the same day. • Plant samples were collected from the most abundant species in the 3 areas, such as P. natans (submersed), L. gibba (free-floating), A. plantago-aquatica (emergent), and F. ulmaria (terrestrial). • Plant samples were divided into root and shoot sections. • 12 species total were used in this study.
Methods- Controlled Study • The plant species F. ulmaria, P. natans, and A. plantago-aquatica were used in this experiment. • A heavy metal mixture was added to half of the plant samples, the others were left as controls. • All plants were cleaned with water. • A flame absorption spectrophotometer determined the metal concentrations. • ANOVA was used to statistically analyze the data.
Results • Zinc concentrations in plants were between 16-451µg 1/g DW. • Copper concentrations in plants were between 2.7-94 µg 1/g DW • Cadmium concentrations in plants were between 04-48 µg -1 DW • Lead concentrations in plants were between 30-26 µg 1/g DW
Discussion • The submersed plant species removed more metal contaminants (e.g. P. natans). • The three areas showed that different plant species contain various levels of metal concentrations. • The plants showed an ability to intake more contaminants at higher metal concentration periods. (e.g. heavy rains). • The majority of the terrestrial and aquatic plants used in this study were effective at removing heavy metal contamination from stormwater.
Critique • Good and important study. • Needed more plant species in the controlled study. • Lack of data from other types of stormwater contamination studies. • Plant and soil collection occurred on only 1 day in both the field and controlled experiments.
Contact Information • For more information please contact: Gianna M. Grabowski (586) 773-0723 firstname.lastname@example.org • Questions???