See more from this Session: General Soil and Environmental Quality Posters: I
Tuesday, October 18, 2011
Henry Gonzalez Convention Center, Hall C, Street Level
The aim of this study was to assess the effects of phosphorus (P) and iron (Fe) on the root elongation (RE) of lettuce in arsenic (As)-spiked soils, using the response surface methodology (RSM). To stabilize the interaction between As and Fe in a soil preparation, the sequential incorporation method between Fe and P (SIMFe-P) was applied. From a phytotoxicity assay, As in roots (Asroot) was negatively associated with RE, Fe in soils, and P in roots and soils (Proot and Psoil); whereas, As in soils (Assoil) showed a positive relationship with Asroot. Proot was also positively related to both Psoil and RE. In a model study, only the linear and interaction factors were observed to be significant. As and interaction factor between P and Fe showed negative coefficients but others showed positive. Especially, P, As, and interaction factor between As and Fe (As*Fe) showed higher explanations of the response (> 14%). These results indicated that although As in soils inhibited RE, P and As*Fe positively affect. From a confirmation study, RE on exposure to As was verified to be much greater in soils treated by SIMFe-P than in soils separately treated with the two elements. Although the ranges of the soil parameters and test soils studied were limited, the application of SIMFe-P to As-contaminated soils might be expected to have an advantage during the early-stage of plant root growth. Also, the approaches from RSM might be considered to be suitable for interpreting the interactions between many factors in soils.