|Smith Jr, Sammie|
Submitted to: Chemosphere
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/20/2006
Publication Date: 9/5/2006
Citation: Bouldin, J.L., Farris, J.L., Moore, M.T., Smith Jr, S., Cooper, C.M. 2006. Hydroponic uptake of atrazine and lambda-cyhalothrin in Juncus effusus and Ludwigia peploides. Chemosphere. Vol 65/6 pp 1049-1057. Interpretive Summary: Aquatic plants have recently demonstrated the ability to absorb potentially harmful contaminants from the water flowing by them. Laboratory experiments were conducted examining the ability of two common plants found in agricultural drainage ditches to sorb two commonly used pesticides. Approximately 98% of the insecticide was sorbed to root material of one plant species, while 25% of the same insecticide, in a different plant species, was translocated to upper plant portions. These experiments will aid in the development of more efficient best management practice designs for controlling agricultural runoff.
Technical Abstract: Phytoremediation encompasses an array of plant-associated processes known to mitigate contaminants from soil, sediment, and water. Modification of pesticides associated with agricultural runoff includes processes directly associated with aquatic macrophytes in addition to changes in soil geochemistry and associated rhizospheric degradation. Remediation attributes of two vegetative species common to agricultural drainages in the Mississippi Delta, USA, were assessed using atrazine and lambda-cyhalothrin. Concentrations used in 8-d hydroponic exposures were calculated using recommended field applications and a 5% runoff model from a 0.65-cm rainfall event on a 2.02-ha field. While greater atrazine uptake was measured in Juncus effusus, greater lambda-cyhalothrin uptake occurred in Ludwigia peploides. Maximum pesticide uptake was reached within 48 h for each exposure and subsequent translocation of pesticides to upper plant biomass occurred in macrophytes exposed to atrazine. Sequestration of 98.2% of lambda-cyhalothrin in roots of L. peploides was measured after 8 d. Translocation of lambda-cyhalothrin in J. effusus resulted in 25.4% of pesticide uptake partitioned to upper plant biomass. These individual macrophyte remediation studies measured species- and pesticide-specific uptake rates, indicating that seasonality of pesticide applications and macrophyte emergence might interact strongly to enhance mitigation capabilities in edge-of-field conveyance structures.