Background:
“Phytoremediation uses plants to clean up environmental contamination in soil, air, and water, offering a potentially cost-effective and less environmentally disruptive alternative to traditional methods of remediation.
Phytoremediation methods include phytoextraction for inorganic pollutants, phytodegradation for organic contaminants, phytovolatilization for releasing volatile substances, phytostabilization for immobilizing pollutants, and phytostimulation for enhancing microbial activity in the rhizosphere.”
From: Klein, M.A., Papoyan, A., & Kochian, L.V. (2025, April). Phytoremediation. AccessScience.
Plants may be especially effective in remediating nitrate when used in buffer strips separating farm fields from water sources and in wetlands in both rural and urban areas.
Sources:
*Choudhary, M., Muduli, M., & Ray, S. (2022). A comprehensive review on nitrate pollution and its remediation: conventional and recent approaches. Sustainable Water Resources Management, 8(4), 113. [Cited by]
“Recently, getting pure water easily is becoming a difficult task for the world. Different sources such as industrial, municipal, urban, and agricultural runoff are principal contributors to water pollution. Nitrate, an inorganic form of nitrogen, one of the water pollutants, can destroy water quality ecologically and clinically by causing eutrophication in the aquatic bodies and, methemoglobinemia (blue baby syndrome) in human infants, other health complications in animals. Traditionally, various methods have been trailed by the industries and wastewater plants to diminish the concentration of nitrate from the polluted water before discharging into the nearby water bodies. In the current decade, innovative, tremendous, and efficient technologies have been developed to reduce nitrate concentration and boost water quality. This paper highlights the most used physical and chemical approaches (ion exchange, reverse osmosis, adsorption, electrodialysis, electrocoagulation, electroreduction, etc.) and biological approaches (microbial, phytoremediation), other hybrid systems and their unique features. In addition, operational conditions, mechanisms, advantages, shortcomings, recent advancements, removal efficiency, and cost-effectiveness were discussed to help the world eliminate this significant problem associated with water pollution and further develop a sustainable hybrid system. Besides it, the paper presents the recovery procedure for nitrate and ammonium. From the detailed literature gathered, the hybrid technology was fantastic compared to stand-alone approaches. The biological methods were unmatchable with others regarding cost, energy consumption, nitrate reduction, nitrate removal, and energy harvest.”
*Regni, L., Bartucca, M. L., Pannacci, E., Tei, F., Del Buono, D., & Proietti, P. (2021). Phytodepuration of Nitrate Contaminated Water Using Four Different Tree Species. Plants, 10(3), 515. [PDF] [Cited by]
“Water pollution by excessive amounts of nitrate (NO3−) has become a global issue. Technologies to clean up nitrate-contaminated water bodies include phytoremediation. In this context, this research aimed to evaluate four tree species (Salix alba L., Populus alba L., Corylus avellana L. and Sambucus nigra L.) to remediate nitrate-contaminated waters (100 and 300 mg L−1). Some physiological parameters showed that S. alba L. and P. alba L. increased particularly photosynthetic activity, chlorophyll content, dry weight, and transpired water, following the treatments with the above NO3− concentrations. Furthermore, these species were more efficient than the others studied in the phytodepuration of water contaminated by the two NO3− levels. In particular, within 15 days of treatment, S. alba L. and P. alba L. removed nitrate quantities ranging from 39 to 78%. Differently, C. avellana L. and S. nigra L. did not show particular responses regarding the physiological traits studied. Nonetheless, these species removed up to 30% of nitrate from water. In conclusion, these data provide exciting indications on the chance of using S. alba L. and P. alba L. to populate buffer strips to avoid NO3− environmental dispersion in agricultural areas.”
*Shyamala, S., N, A. M., Pakshirajan, K., Van, T. T., & Rene, E. R. (2019). Phytoremediation of nitrate contaminated water using ornamental plants. Journal of Water Supply : Research and Technology – AQUA, 68(8), 731-743. [Cited by]
“This work aims at evaluating the potential of two ornamental plant species, i.e., money plant (Epiprennum aureum) and arrowhead plant (Syngonium podophyllum), to treat nitrate containing wastewater. Statistically designed experiments were performed to ascertain the effect of initial nitrate concentration (40–120 mg/L), growth period (1–12 days) and plant density (20–80 g/L) on nitrate removal. Based on the results of analysis of variance (ANOVA), it was observed that the individual effects (F = 78.04 and P = 0.013) of process parameters influenced the nitrate removal efficiency by money plant stronger than the 2-way (F = 0.2 and P = 0.89) and 3-way interaction effects (F = 0.46 and P = 0.569). In the case of the arrowhead plant, the individual effects significantly affected the nitrate removal efficiency than the 2-way and 3-way interaction effects. Low nitrate concentrations (40 mg/L) and high plant density (80 g/L), showed ∼88% nitrate removal by arrowhead plant, during a growth period of 6 d. On the contrary, under similar conditions, the money plant showed a nitrate removal efficiency of ∼93% during a growth period of 12 d. Concerning the removal kinetics, an increase in the growth period increased the nitrate removal rate for both the plants.”
*Russelle, M. P., Lamb, J. F., Montgomery, B. R., Elsenheimer, D. W., Miller, B. S., & Vance, C. P. (2001). Alfalfa rapidly remediates excess inorganic nitrogen at a fertilizer spill site. Journal of Environmental Quality, 30(1), 30-36. [Cited by]
“By 1996, standard remediation techniques had significantly reduced the concentration of nitrate nitrogen (NO−3–N) in local ground water at the site of a 1989 anhydrous ammonia spill, but NO−3–N concentrations in portions of the site still exceeded the public drinking water standard. Our objective was to determine whether local soil and ground water quality could be improved with alfalfa (Medicago sativa L.). A 3-yr study was conducted in replicated plots (24 by 30 m) located hydrologically upgradient of the ground water under the spill site. Three alfalfa entries [‘Agate’, Ineffective Agate (a non-N2–fixing elite germplasm similar to Agate), and MWNC-4 (an experimental germplasm)] were seeded in the spring of 1996. Corn (Zea mays L.) or wheat (Triticum aestivum L.) was seeded adjacent to the alfalfa each year. Crops were irrigated with N-containing ground water to meet water demand. During the 3-yr period, about 540 kg of inorganic N was removed from the aquifer through irrigation of 4.9 million L water. Cumulative N removal from the site over 3 yr was 972 kg N ha−1 in Ineffective Agate alfalfa hay, compared with 287 kg N ha−1 for the annual cereal grain. Soil solution NO−3 concentrations were reduced to low and stable levels by alfalfa, but were more variable under the annual crops. Ground water quality improved, as evidenced by irrigation water N concentration. We do not know how much N was removed by the N2–fixing alfalfas, but it appears that either fixing or non-N2–fixing alfalfa will effectively remove inorganic N from N-affected sites.”
Other Sources:
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