Effects of amendments on soil availability and phytoremediation potential of

MITTON, FRANCESCA; GONZALEZ MARIANA; PEÑA ARANZAZU; MIGLIORANZA KARINA SILVIA BEATRIZ

JOURNAL OF HAZARDOUS MATERIALS.

ELSEVIER SCIENCE BV

Año: 2012 p. 62 - 68

0304-3894

Combining technologies offer the greatest potential to efficiently phytoremediate contaminated soils. Is known that as sequestration occurs, pollutants availability can sharply decline, dramatically limiting remediation. This works deals with the evaluation of organic amendments on the phytoremediation of contaminated soils with p,p-DDT: 101.32 ng g-1, p,p-DDE: 381.38 ng g-1 and p,p-DDD: 0.39 ng g-1. The effects of root exudates, non ionic surfactant (Tween 80) and carboxylic acids (citric and oxalic) on DDTs desorption and availability from soil were tested in addition with the uptake and translocation by willow plants. Amendments with carboxylic acids increase the concentration of the p,p-DDE and p,p-DDD in soils until 422.48 and 5.28 ng g-1 respectively. Moreover, watering with carboxylic acids resulted in a significant enhancement of the quantities of p,p-DDT and p,p-DDE desorbed from soil connected with an increase of organic carbon in solution. Willows accumulated large amounts of the contaminant and in all treatments roots showed the highest levels followed by stems and leaves. Plants watered with carboxylic acids showed the highest translocation of DDTs and phytoextraction potential (4.17%), while watering with root exudates or Tween 80 showed a diminishing on this factor. Results indicates that addition of carboxylic acids enhance the DDTs bioavailability by means of increasing dissolved organic carbon followed by the increased uptake and translocation by willows plants. Thus, the enhancing of soluble organic carbon will promote contaminant release as well improve cleaning strategies.