Title:
Phytoremediation Potential of Oilseed Crops for Heavy Metal Contaminated Soils
Author(s):
Costa, J., Gomes, L., Abias, M., Germaną, F., Cumbane, B., Zanetti, F., Monti, A., Fernando, A.L.
Document(s):
Paper
Abstract:
The cultivation of industrial crop species to produce bioproducts, biomaterials, bioenergy and biofuels, represents an effective option for the partial substitution of fossil-based feedstocks. In addition, some crops have also the ability to tolerate and remove contaminants from the soil, contributing to remediate soil contamination. Oilseed crops represent a source of medium-chain fatty acids and medium-chain polymer building blocks that can be used for the production of plastics, surfactants, detergents, lubricants, plasticizers and other products. In this context, this work aims to assess the potential of some oil crops for the phytoremediation of soils contaminated with heavy metals and, simultaneously, being able to produce biomass and oils that can contribute to the bioeconomy. Therefore, different oil crops, Thlaspi arvense, Brassica carinata, Camelina sativa (Cypress, Midas and Luna varieties) and Crambe abyssinica were sowed in different soils artificially contaminated with Zn: 900 mg/kg; Pb: 900 mg/kg; Cd: 8 mg/kg; or Ni: 220 mg/kg. This work was carried out in pots, under semi-controlled conditions, with the duration of two vegetative cycles. All tested oil crops can be considered tolerant to the heavy metals in this study (tolerance index, yields in contaminated soils/yields in control soils, higher than 0.50) except for T. arvense that only showed a tolerance index in the range 0.22-0.46. C. abyssinica was the oil crop that presented the highest tolerance index to the different heavy metal contaminated soils (> 0.75). C. sativa, Cypress variety, was the most productive crop (160 g/m2), followed by Crambe abyssinica and Brassica carinata (average, 140 g/m2). Camelina sativa varieties Midas and Luna showed intermediate stem yields (average, 70 g/m2). The least productive crop was Thlaspi arvense (average 50 g/m2). Most of the oil crops showed higher tolerance to Pb (average tolerance index of 0.68), medium tolerance to Zn and Cd (average tolerance index of 0.59 and 0.58, respectively) and less tolerance to Ni (average tolerance index of 0.50). All oil crops exhibited high phytoextraction potential for Zn, Cd and Ni and reduced potential for Pb. B. carinata showed the greatest accumulation index (metal content in the biomass from contaminated pots/metal content in the biomass from control pots) for all metals. T. arvense presented the lowest accumulation index for all the metals in this study. Interestingly, the siliquae fraction of all tested crops presented low metal contents and, therefore, the oil can represent a feedstock for the oleochemical industry, contributing to decarbonizing the economy.
Keywords:
heavy metals, land use, polluted soil, oil crops, phytoremediation, contaminated soils
Topic:
Sustainable Resources for Decarbonising the Economy
Subtopic:
Innovative Biomass Production for Energy Integrated into Traditional Agri-Forestry Systems
Event:
29th European Biomass Conference and Exhibition
Session:
1CV.1.5
Pages:
218 - 221
ISBN:
978-88-89407-21-9
Paper DOI:
10.5071/29thEUBCE2021-1CV.1.5
Price:
FREE
