EFFECTS OF NITROGEN AND PHOSPHORUS LEVELS,AND FROND-HARVESTING ON ABSORPTION,TRANSLOCATION AND ACCUMULATION OF ARSENIC BY CHINESE BRAKE FERN (PTERIS VITTATA L.) |
| |
Authors: | Seenivasan Natarajan Robert H Stamps Uttam K Saha Lena Q Ma |
| |
Institution: | 1. University of Florida, Institute of Food and Agricultural Science (IFAS), Mid-Florida Research and Education Center (MREC), Department of Environmental Horticulture , Apopka , FL , USA;2. University of Florida, Soil and Water Science Department , Gainesville , FL , USA |
| |
Abstract: | This hydroponic experiment was conducted to determine the effects of nitrogen (N) and phosphorus (P) levels and frond-harvesting on the effectiveness of arsenic (As)-hyperaccumulator Chinese brake fern (Pteris vittata L.) to remove As from contaminated groundwater collected from south Florida. Three-month old ferns were grown in 38-L plastic tanks (two ferns per tank) containing 30-L of As-contaminated water (130 μg·L?1 As), which was amended with modified 0.25 strength Hoagland's solution #2. Two N (26 or 52 mg·L?1) and two P levels (1.2 and 2.4 mg·L?1) were tested in one experiment, whereas the effect of frond-harvesting was tested in a separate experiment. Initially, N had little effect on plant As removal whereas low P treatment was more effective than high P and As was reduced to <5 μg·L?1 in 28 d compared to 35 d. For well-established ferns, N and P levels had little effect. Reused fern, with or without harvesting the As-rich fronds, took up arsenic more rapidly so the As concentration in the groundwater declined faster (130 to ~10 μg·L?1 in 8 h). Regardless of the treatments, most As (85–93%) was located in the aboveground tissue (rhizomes and fronds). Frond As concentrations were higher for non-harvested ferns than for ferns where fronds were partially harvested prior to treatment. Conversely, rhizomes accumulated more arsenic in ferns where fronds had been partially harvested. Low-P treatment coupled with reuse of more established ferns with or without harvesting fronds can be used to effectively remove arsenic from contaminated water using P. vittata |
| |
Keywords: | Pteris vittata phytofiltration arsenic nitrogen phosphorus frond harvesting groundwater kinetic parameters translocation factor bioconcentration factor |
|
|