Small-scale Economies Project
“Plant-based remediation of arsenic-contaminated soil: Successes and challenges”

Date & Hours: Friday, July 1, 2016, 15:00 - 16:30 (45mins talk and Q&A)
Venue: Seminar Room 3 & 4, RIHN( →Access)
Organizer: Small-scale Economies Project
Speaker: Sarick Matzen (University of California, Berkeley)
Language: English with consecutive translation

Soils globally are contaminated with arsenic, a carcinogen, with sources including agriculture and mining. When dangerous levels of soil contaminants are discovered, conventional remediation methods call for excavating and replacing soil. However, this is very expensive and wasteful. Researchers have discovered a technique to remediate arsenic contamination, called phytoremediation, which uses green plants to remove arsenic while leaving the soil in place. The brake fern (Pteris vittata L.) can take up arsenic from the soil through its roots and transport it to its fronds, where it is accumulated at very high concentrations. Harvesting the fronds removes arsenic from the soil over time. While this new method for decontaminating soil is promising, there is considerable work to do before this fern can be used in real-life situations. For example, the fern currently removes arsenic from soil very slowly.

Our goal is to investigate ways to make phytoremediation with the brake fern more effective and efficient. We investigated how intrinsic properties of soil, such as texture, and soil treatments, such as fertilization, affect the uptake of arsenic in the ferns. We combined results of field, greenhouse, and laboratory bench-top studies to understand processes at multiple scales. Our results show that soil texture and arsenic concentration affect arsenic uptake in the fern, with very high concentrations achieved in ferns growing in some but not all conditions present in our site. However, our best estimates of remediation times are on the order of decades. We are currently considering the role of arsenic availability in phytoremediation, to determine whether soils can be available for reuse once plant available arsenic is removed by the fern. This talk will introduce arsenic as a soil contaminant, consider emerging sustainable methods for remediating arsenic contamination, discuss our current results, and share our future work.

Contact:Ms. Kobayashi Small-scale Economies Project (Room 8),
TEL: 075-707-2373
 ⇒ Flyer (PDF)