Feasibility of using forage grasses and legumes for phytoremediation of organic pollutants

Abstract

Selected forage and soil conservation grasses and legumes were evaluated in the greenhouse for their abilities to stimulate dissipation of PCB, TNT, and pyrene in a soil. The grasses tested were tall fescue (Festuca arundinacea Schreb), reed canarygrass( Phalaris arundinacea L.), switchgrass ( Panicum variegatum L.), and deertongue (Panicum clandestinum L.). The legumes were alfalfa (Medicago sauva L.), crownvetch (Coronilla varia L.), sericea lespedeza (Lespedeza cuneata Dum-Cours.), and flatpea (Wagner pea) ( Lathyrus sylvestris L). The plants were grown in 13.5x15.0 cm pots containing soils that were fortified with 100 mg/kg nominal concentrations of the respective compounds andaged in the laboratory. After six months, 51% or less of an initial 100 mg/kg dose of aroclor 1248 was recovered from soils planted with reed canarygrass, switchgrass, and flatpea. Between 64-70% of the initial dose was recovered from soils planted with tall fescue, deer tongue, and sericea lespedeza, and about 80 % 1646 KUDJO DZANTOR, CHEKOL, AND VOUGH or more was recovered from soils that were planted with alfalfa and crownvetch as well as soil that was left implanted. During the same period, <0.5% of the initial dose of TNT and <3% of pyrene were recovered from soils that were fortified with those compounds, including unplanted controls. Laboratory flask experiments that compared the dissipation of TNT and pyrene in natural soils and soils containing microbial inhibitor suggested that microbial transformation accounted for a major portion of the loss of TNT and pyrene in this soil. A comparison of the dissipation of TNT and pyrene in two different soils reinforces previously well-documented strong role of organic matter in the overall fate of TNT and pyrene in soil.

Phytoremediation of hydrocarbon contaminants in subantarctic soils: An effective management option

“…The majority of studies report an increase in microbes within planted soil across a range of contamination levels, relative to unplanted soil (Siciliano et al, 2003;Chiapusio et al, 2007;Gaskin et al, 2008;Gaskin and Bentham 2010;Barrutia et al, 2011) and comparatively few studies report no difference (Radwan et al, 1998;Kudjo Dzantor et al, 2000;Chaiapusio et al, 2007;Cofield et al, 2007). However, an increase in culturable microbial populations in planted soils was only seen at low concentrations of TPH in this study.…”

Rhizosphere remediation of chlorpyrifos in mycorrhizospheric soil using ryegrass

“…These rhizodeposits also stimulate the survival and action of bacteria which subsequently results in efficient degradation of pollutants [20]. In present study, the chosen plant species-ryegrass proved competent for rhizosphere bioremediation of chlorpyrifos in the soil which may be credited to its advantageous features of having fibrous root system providing large specific surface area to interact with microorganism [21] and capacity to release high amount of exudates in the rhizosphere [22]. The study conducted by Korade and Fulekar have also found that ryegrass can effectively be used for the remediation of anthracene in the soil [23].…”

Polycyclic Aromatic Hydrocarbons Degradation Techniques: A Review

“…Research has indicated that various grasses and leguminous plants are potential candidates for phytodegradation of organics (Adam & Duncan, 1999). Some tropical plants have also been reported to show effective degradation tendency due to inherent properties such as deep fibrous root system and tolerance to high hydrocarbon and low nutrient availability (Dzantor, Chekol, & Vough, 2000). Recently published data have revealed that the tall fescue grass (Festuca arundinacea) and switch grass (Pannicum virgatum) are capable of degrading about 38% of pyrene in 190 days (Chen, Banks, & Schwab, 2003).…”