Agronomic Approaches for Remediation of Contaminated Soils

A special issue of Agronomy (ISSN 2073-4395). This special issue belongs to the section "Soil and Plant Nutrition".

Deadline for manuscript submissions: closed (31 July 2020) | Viewed by 48346

Special Issue Editors


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Guest Editor
Department of Agricultural Sciences, Division of Plant Biology and Crop Science, University of Naples Federico II, Via Università 100, 80055 Naples, Italy
Interests: organic farming; agronomy soil fertility; agronomy bioremediation; soil erosion

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Guest Editor
Department of Agricultural Sciences, Division of Plant Biology and Crop Science, University of Naples Federico II, Via Università 100, 80055 Naples, Italy
Interests: soil fertility management; phytoremediation; ecosystem services; environmental pollution

Special Issue Information

Dear Colleagues,

Soil contamination is worldwide threat to human health and environmental quality. The more widely used remediation techniques destroy soil fertility, making it unsuitable for growing plants. Biological approaches for the remediation of contaminated soils are increasing, since they allow one to reduce economic cost while at the same time safeguarding soil quality and ecosystem services. Ecological structures, such as permanent turfgrass, and tree or cane stands, allow one to secure contaminated sites by interrupting contaminant movements toward other environmental compartments. Selected plants can be useful for extracting the bioavailable fraction of PTEs. Plants can also be used for risk assessment (e.g., phytoscreening, risks of food chain contamination). Several agronomic or biological tools can improve the efficiency of remediation (e.g., compost fertilization, PGPR for improving phytoextraction or bioremediation). Please share your success stories from research in contaminated sites around the world in this Special Issue. Submissions on but not limited to the following topics are invited: (1) Iinnovative and novel approaches for risk assessment (chemical or biological tools for evaluating bioavailability); (2) agronomic practices related to improve phytostabilization, phytoextraction, and rhizofiltration; (3) valorisation of biomasses produced in contaminated sites; (4) use of crops for risk assessment of contamination of food-chain; (5) the impact of phytoremediation on soil ecosystem services; and (6) soil-plant-microbial interactions at the rhizosphere level.

Prof. Dr. Massimo Fagnano
Dr. Nunzio Fiorentino
Guest Editor

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Keywords

  • Phytoscreening
  • Assisted phytoremediation
  • Risk assessment
  • Dietary exposure
  • Interrupting exposure pathways
  • Soil ecosystem services
  • Rhizosphere
  • Bioavailability evaluation
  • Plant-soil interactions
  • Soil conservation and recovery.

Published Papers (13 papers)

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Research

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19 pages, 1372 KiB  
Article
Assessment of the Bioavailability and Speciation of Heavy Metal(loid)s and Hydrocarbons for Risk-Based Soil Remediation
by Diana Agrelli, Antonio Giandonato Caporale and Paola Adamo
Agronomy 2020, 10(9), 1440; https://doi.org/10.3390/agronomy10091440 - 22 Sep 2020
Cited by 16 | Viewed by 2848
Abstract
For the assessment of the environmental and sanitary risks deriving from contamination of agricultural soils, it is crucial to identify and characterize the contaminants and study the soil chemical properties influencing their mobility and bioavailability. This information is essential for the selection of [...] Read more.
For the assessment of the environmental and sanitary risks deriving from contamination of agricultural soils, it is crucial to identify and characterize the contaminants and study the soil chemical properties influencing their mobility and bioavailability. This information is essential for the selection of the best site remediation and securing strategy. The study site of this work is agricultural land of 6 ha in the province of Naples (Italy) subject to the past illegal burial of industrial wastes, principally from tanneries. With the aim of identifying the contaminants and assessing their mobility and bioavailability, the soil of the site was characterized for the main chemical and physical properties and for the concentration of potentially toxic elements and hydrocarbons. The readily and potentially bioavailable fractions of the main metal contaminants and their distribution in the soil geochemical fractions were determined by extraction in 1 M of NH4NO3, 0.05 M of ethylenediaminetetraacetic acid (EDTA) pH 7, and European Community Bureau of Reference (EU-BCR) sequential fractionation. Further, the speciation of heavy hydrocarbons and chromium was carried out. The agricultural soil was widely contaminated by chromium, zinc, and heavy hydrocarbons (up to 4487, 1846, and 1800 mg/kg, respectively). In some sub-areas, contaminations by cadmium, lead, and copper (up to 283, 417, and 1183 mg/kg, respectively) were also observed. The chromium was found to be scarcely mobile and bioavailable and was mainly associated with the oxidizable, residual, and reducible fractions of the soil (on average 56%, 25%, and 19% of the total, respectively). However, chromium speciation revealed the presence of a significant amount of highly toxic Cr(VI) (above the legal threshold of 2 mg/kg), despite the low oxidizing power of the soil. Zinc was more mobile and bioavailable than chromium and was mainly distributed among the acetic acid-extractable and reducible fractions of the soil (on average 28% and 47% of the total, respectively). Cadmium was found to be very mobile and bioavailable, and was mainly distributed in the acetic acid-extractable and reducible fractions of the soil (on average 40% and 45% of the total). The speciation of heavy hydrocarbons showed that they consist almost entirely of long-chain aliphatic hydrocarbons, considered not very toxic and immobile. These results suggest that the use of not-edible plant coverage might be the best securing and remediation action for the study site, with the potential to preserve the soil ecosystem services, contain the risk of soil erosion and particle dispersion, and phytoextract the bioavailable metals. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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18 pages, 1167 KiB  
Article
Interactions between the Hyperaccumulator Noccaea caerulescens and Brassica juncea or Lupinus albus for Phytoextraction
by Isabel Martínez-Alcalá, Rafael Clemente and María Pilar Bernal
Agronomy 2020, 10(9), 1367; https://doi.org/10.3390/agronomy10091367 - 11 Sep 2020
Cited by 2 | Viewed by 2454
Abstract
Trace-element-contaminated soils cause environmental concern and represent a source of contamination for surrounding areas. Phytoremediation uses plants to diminish the environmental risks associated with this contamination. When the final aim is the extraction of the pollutants, this technique requires the use of plants [...] Read more.
Trace-element-contaminated soils cause environmental concern and represent a source of contamination for surrounding areas. Phytoremediation uses plants to diminish the environmental risks associated with this contamination. When the final aim is the extraction of the pollutants, this technique requires the use of plants that are able to accumulate high concentrations of the target elements in their aerial part, while producing high plant biomass. Here, pot experiments were carried out in order to determine the interaction between a hyperaccumulator (Nocaea caerulescens) and a metal excluder (Lupinus albus) or an accumulator (Brassica juncea) species regarding their trace element accumulation/exclusion capacity when sharing the rhizosphere. The plants were grown alone or were cocultivated in soils with different levels of trace element contamination. The Zn concentration in N. caerulescens plants was lower in cocultivation with B. juncea than when they were grown alone, indicating competition between the two species for Zn uptake. Contrastingly, when grown with L. albus, the Zn concentrations in N. caerulescens plants were higher than when grown alone. Therefore, under climatic conditions adequate for N. caerulescens growth, cocultivation with L. albus could favor Zn phytoextraction, while in the case of B. juncea, crop rotation rather than cocultivation is recommended for efficient phytoextraction. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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25 pages, 2295 KiB  
Article
Securing of an Industrial Soil Using Turfgrass Assisted by Biostimulants and Compost Amendment
by Donato Visconti, Antonio Giandonato Caporale, Ludovico Pontoni, Valeria Ventorino, Massimo Fagnano, Paola Adamo, Olimpia Pepe, Sheridan Lois Woo and Nunzio Fiorentino
Agronomy 2020, 10(9), 1310; https://doi.org/10.3390/agronomy10091310 - 2 Sep 2020
Cited by 8 | Viewed by 3092
Abstract
This work aimed to study the effects of compost (applied at two rates) and two commercial microbial biostimulants on the mobility and bioavailability of potentially toxic elements (PTEs) in an industrial soil phytostabilized by Dactylis glomerata L. or a mixed stand of grasses [...] Read more.
This work aimed to study the effects of compost (applied at two rates) and two commercial microbial biostimulants on the mobility and bioavailability of potentially toxic elements (PTEs) in an industrial soil phytostabilized by Dactylis glomerata L. or a mixed stand of grasses (Lolium perenne L., Poa pratensis L. and Festuca arundinacea Shreb.). The soil showed very high pseudototal and bioavailable concentrations of cadmium (Cd) and lead (Pb), due to improper lead-acid batteries storage. Compost amendment in combination with the two biostimulants produced the best outcomes in terms of plant growth and nutrient uptake. The same mix of beneficial microbes improved soil biological fertility enhancing soil nitrogen fixing and ammonia oxidizing bacteria, while reduced the pore water and NH4NO3 extractable concentrations of Cd and at lower extent of Pb in soil. Accordingly, the lower mobility and bioavailability of Cd in soil determined a lower uptake and accumulation of Cd in shoots of different grass species. Our results suggest that a green cap with turfgrass assisted by biostimulants and compost amendment in PTE-contaminated industrial sites could be a reliable and effective practice to protect and restore soil biological fertility and to reduce the risk of PTE dispersion in the surrounding environment. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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16 pages, 2447 KiB  
Article
Comparison of Two Inoculation Methods of Endophytic Bacteria to Enhance Phytodegradation Efficacy of an Aged Petroleum Hydrocarbons Polluted Soil
by Małgorzata Pawlik, Tomasz Płociniczak, Sofie Thijs, Isabel Pintelon, Jaco Vangronsveld and Zofia Piotrowska-Seget
Agronomy 2020, 10(8), 1196; https://doi.org/10.3390/agronomy10081196 - 14 Aug 2020
Cited by 16 | Viewed by 3882
Abstract
Endophyte-enhanced phytodegradation is a promising technology to clean up polluted soils. To improve the success rate of this nature-based remediation approach, it is important to advance the inoculation method as this has been shown to strongly affect the final outcome. However, studies evaluating [...] Read more.
Endophyte-enhanced phytodegradation is a promising technology to clean up polluted soils. To improve the success rate of this nature-based remediation approach, it is important to advance the inoculation method as this has been shown to strongly affect the final outcome. However, studies evaluating inoculation strategies and their effect on hydrocarbon degradation are limited. This study aims to investigate two different manners of endophyte inoculation in Lolium perenne growing in an aged petroleum hydrocarbon polluted soil: (1) direct soil inoculation (SI), and (2) pre-inoculation of the caryopses followed by soil inoculation (PI). Different endophytic bacterial strains, Rhodococcus erythropolis 5WK and Rhizobium sp. 10WK, were applied individually as well as in combination. Depending on the method of inoculation, the petroleum hydrocarbon (PHC) degradation potential was significantly different. The highest PHC removal was achieved after pre-inoculation of ryegrass caryopses with a consortium of both bacterial strains. Moreover, both strains established in the aged-polluted soil and could also colonize the roots and shoots of L. perenne. Importantly, used endophytes showed the selective colonization of the environment compartments. Our findings show that the method of inoculation determines the efficiency of the phytodegradation process, especially the rate of PHC degradation. This study provides valuable information for choosing the most cost-effective and beneficial means to optimize phytodegradation. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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20 pages, 1931 KiB  
Article
Comparative Study on Multiway Enhanced Bio- and Phytoremediation of Aged Petroleum-Contaminated Soil
by Natalia Ptaszek, Magdalena Pacwa-Płociniczak, Magdalena Noszczyńska and Tomasz Płociniczak
Agronomy 2020, 10(7), 947; https://doi.org/10.3390/agronomy10070947 - 1 Jul 2020
Cited by 16 | Viewed by 3414
Abstract
Bioremediation and phytoremediation of soil polluted with petroleum hydrocarbons (PHs) are an effective and eco-friendly alternative to physicochemical methods of soil decontamination. These techniques can be supported by the addition of effective strains and/or surface-active compounds. However, to obtain maximum efficacy of bioremediation, [...] Read more.
Bioremediation and phytoremediation of soil polluted with petroleum hydrocarbons (PHs) are an effective and eco-friendly alternative to physicochemical methods of soil decontamination. These techniques can be supported by the addition of effective strains and/or surface-active compounds. However, to obtain maximum efficacy of bioremediation, the interactions that occur between the microorganisms, enhancement factors and plants need to be studied. Our study aimed to investigate the removal of petroleum hydrocarbons from an aged and highly polluted soil (hydrocarbon content about 2.5%) using multiway enhanced bio- and phytoremediation. For this purpose, 10 enhanced experimental groups were compared to two untreated controls. Among the enhanced experimental groups, the bio- and phytoremediation processes were supported by the endophytic strain Rhodococcus erythropolis CDEL254. This bacterial strain has several plant growth-promoting traits and can degrade petroleum hydrocarbons and produce biosurfactants. Additionally, a rhamnolipid solution produced by Pseudomonas aeruginosa was used to support the total petroleum hydrocarbon loss from soil. After 112 days of incubation, the highest PH removal (31.1%) was observed in soil planted with ryegrass (Lolium perenne L. cv. Pearlgreen) treated with living cells of the CDEL254 strain and rhamnolipid solution. For non-planted experimental groups, the highest PH loss (26.1%) was detected for soil treated with heat-inactivated CDEL254 cells and a rhamnolipid solution. In general, the differences in the efficacy of the 10 experimental groups supported by plants, live/dead cells of the strain tested and rhamnolipid were not statistically significant. However, each of these groups was significantly more effective than the appropriate control groups. The PH loss in untreated (natural attenuation) and soils that underwent phytoremediation reached a value of 14.2% and 17.4%, respectively. Even though the CDEL254 strain colonized plant tissues and showed high survival in soil, its introduction did not significantly increase PH loss compared to systems treated with dead biomass. These results indicate that the development of effective biological techniques requires a customized approach to the polluted site and effective optimization of the methods used. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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20 pages, 722 KiB  
Article
Health Risk Assessment in Agricultural Soil Potentially Contaminated by Geogenic Thallium: Influence of Plant Species on Metal Mobility in Soil-Plant System
by Luigi Giuseppe Duri, Donato Visconti, Nunzio Fiorentino, Paola Adamo, Massimo Fagnano and Antonio Giandonato Caporale
Agronomy 2020, 10(6), 890; https://doi.org/10.3390/agronomy10060890 - 23 Jun 2020
Cited by 17 | Viewed by 3074
Abstract
In agricultural soils, thallium (Tl) of geogenic origin may represent a potential risk for human health, mainly via ingestion of food crops. In this work, a pot experiment was carried out to evaluate (1) the bioavailability of Tl and other potentially toxic elements [...] Read more.
In agricultural soils, thallium (Tl) of geogenic origin may represent a potential risk for human health, mainly via ingestion of food crops. In this work, a pot experiment was carried out to evaluate (1) the bioavailability of Tl and other potentially toxic elements (PTEs) in an agricultural soil with naturally occurring Tl; (2) the uptake and accumulation of PTEs in Lactuca sativa L. var. acephala, Diplotaxis tenuifolia L. DC and Silene latifolia Poir; (3) the health risks arising from plant and soil ingestion by different subpopulations and dermal contact of soil by farmers. In soil, only Tl and Pb pseudototal contents were above Italian screening values. Nevertheless, the promptly bioavailable contents of all PTEs were always below internationally recognized trigger values. Plants affected PTE bioavailability in soil by their rhizodepositions and accumulated PTEs in their shoots. Acceptable risks (hazard index < 1) arose from dietary intake of both L. sativa L., D. tenuifolia L. and dermal contact of soil by farmers. Significant health risks can derive from the intake of S. latifolia Poir. (accumulating high Tl concentrations), in particular by children (HI = 74). In conclusion, an adequate management and crop selection are needed to profitably exploit soils with geogenic Tl for agricultural purposes. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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15 pages, 1326 KiB  
Article
The Role of Biochar and Soil Properties in Determining the Available Content of Al, Cu, Zn, Mn, and Cd in Soil
by Niguss Solomon Hailegnaw, Filip Mercl, Kateřina Pračke, Lukáš Praus, Jiřina Száková and Pavel Tlustoš
Agronomy 2020, 10(6), 885; https://doi.org/10.3390/agronomy10060885 - 20 Jun 2020
Cited by 13 | Viewed by 3707
Abstract
The purpose of the study was to understand the mechanisms of biochar-induced changes in the available content of aluminum (Al), cadmium (Cd), zinc (Zn), copper (Cu), and manganese (Mn) in a wide range of soils. Five soils from different regions of the Czech [...] Read more.
The purpose of the study was to understand the mechanisms of biochar-induced changes in the available content of aluminum (Al), cadmium (Cd), zinc (Zn), copper (Cu), and manganese (Mn) in a wide range of soils. Five soils from different regions of the Czech Republic were incubated for 12 weeks with four rates of biochar (0.5%, 2%, 4%, and 8% w/w). The available concentrations of Al, Cd, Zn, Cu, and Mn were determined on the 7th and 84th day of incubation. There was a significant decline in the available content of Al, Zn, Cu, Mn, and Cd except in the available content of Al in one soil, which is characterized by very low Al content, higher cation exchange capacity (CEC), and neutral pH = 7.0. The decline in the mobile contents of Al, Zn, Cu, Mn, and Cd was significant in all cases of 8% biochar rate. The decline in the content of Al, Zn, Cu, Mn, and Cd was mainly due to the increment in soil pH and increment in CEC, decline in dissolved organic carbon (DOC), and the release of exchangeable Ca2+ and K+ from biochar. The application of high amounts of biochar to soil could increase the available content of some metals like Al. On the other hand, biochar could efficiently reduce the mobility of Al, Zn, Cu, Mn, and Cd in soil, while the decline is mainly caused by biochar-induced changes in soil pH, CEC, DOC, and exchangeable Ca2+ and K+ content of treated soils. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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17 pages, 1648 KiB  
Article
Potentially Toxic Element Availability and Risk Assessment of Cadmium Dietary Exposure after Repeated Croppings of Brassica juncea in a Contaminated Agricultural Soil
by Diana Agrelli, Luigi Giuseppe Duri, Nunzio Fiorentino, Eugenio Cozzolino, Massimo Fagnano and Paola Adamo
Agronomy 2020, 10(6), 880; https://doi.org/10.3390/agronomy10060880 - 19 Jun 2020
Cited by 9 | Viewed by 2018
Abstract
Phytoextraction of potentially toxic elements (PTEs) is eco-friendly and cost-effective for remediating agricultural contaminated soils, but plants can only take up bioavailable forms of PTEs, thus meaning that bioavailability is the key for the feasibility of this technique. With the aims to assess [...] Read more.
Phytoextraction of potentially toxic elements (PTEs) is eco-friendly and cost-effective for remediating agricultural contaminated soils, but plants can only take up bioavailable forms of PTEs, thus meaning that bioavailability is the key for the feasibility of this technique. With the aims to assess the phytoextraction efficiency on an agricultural soil contaminated by Cr, Zn, Cd, and Pb and the changes induced by plants in PTE bioavailability and in human health risk due to dietary exposure, in this work we carried out a mesocosm experiment with three successive croppings of Brassica juncea, each followed by Rocket salad as bioindicator. Brassica juncea extracted more Zn and Cd than Cr and Pb, significantly reducing, after three repeated croppings, the bioavailable element concentrations in soil as a result of plant uptake and soil pH changes. For Cd, this reduction did not bring the bioavailable amounts obtained by soil extraction with NH4NO3 below the trigger value of 0.1 mg kg−1 set by some European countries. Nevertheless, the Hazard Quotient for Cd in Rocket salad decreased across three repeated croppings of Brassica juncea. This indicated the beginning of a re-equilibration process between soil PTE forms of different bioavailability, that are in a dynamic equilibrium, thus stressing the need to monitor the possible regeneration of the most readily bioavailable pool. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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14 pages, 1688 KiB  
Article
Dolomite and Compost Amendments Enhance Cu Phytostabilization and Increase Microbiota of the Leachates from a Cu-Contaminated Soil
by Laura Giagnoni, Luiz Gustavo dos Anjos Borges, Adriana Giongo, Andressa de Oliveira Silveira, Alexandria N. Ardissone, Eric W. Triplett, Michel Mench and Giancarlo Renella
Agronomy 2020, 10(5), 719; https://doi.org/10.3390/agronomy10050719 - 18 May 2020
Cited by 8 | Viewed by 3226
Abstract
The chemical properties, ecotoxicity, and microbiome of leachates from phytomanaged Cu-contaminated soils were analyzed. The phytomanagement was carried out using Cu-tolerant poplar Populus trichocarpa × deltoides cv. Beaupré and black bent Agrostis gigantea L., aided by soil amendments, i.e., dolomitic limestone (DL) and [...] Read more.
The chemical properties, ecotoxicity, and microbiome of leachates from phytomanaged Cu-contaminated soils were analyzed. The phytomanagement was carried out using Cu-tolerant poplar Populus trichocarpa × deltoides cv. Beaupré and black bent Agrostis gigantea L., aided by soil amendments, i.e., dolomitic limestone (DL) and compost (OM), alone and in combination (OMDL). Plants plus either DL or OMDL amendments reduced in leachates the electrical conductivity, the Cu concentration, and the concentration of total organic C except for the OMDL treatment, and decreased leachate toxicity towards bacteria. Total N concentration increased in the OM leachates. The aided phytostabilization increased the culturable bacteria numbers and the proportion of Cu-resistant bacteria in the leachates, as compared to the leachate from the untreated soil. Phytomanagement also enriched the microbial communities of the leachates with plant beneficial bacteria. Overall, the Cu stabilization and phytomanagement induced positive changes in the microbial communities of the soil leachates. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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16 pages, 2106 KiB  
Article
Phytostabilization of Polluted Military Soil Supported by Bioaugmentation with PGP-Trace Element Tolerant Bacteria Isolated from Helianthus petiolaris
by Anabel Saran, Valeria Imperato, Lucia Fernandez, Panos Gkorezis, Jan d’Haen, Luciano Jose Merini, Jaco Vangronsveld and Sofie Thijs
Agronomy 2020, 10(2), 204; https://doi.org/10.3390/agronomy10020204 - 1 Feb 2020
Cited by 22 | Viewed by 4395
Abstract
Lead (Pb) and cadmium (Cd) are major environmental pollutants, and the accumulation of these elements in soils and plants is of great concern in agricultural production due to their toxic effects on crop growth. Also, these elements can enter into the food chain [...] Read more.
Lead (Pb) and cadmium (Cd) are major environmental pollutants, and the accumulation of these elements in soils and plants is of great concern in agricultural production due to their toxic effects on crop growth. Also, these elements can enter into the food chain and severely affect human and animal health. Bioaugmentation with plant growth-promoting bacteria (PGPB) can contribute to an environmentally friendly and effective remediation approach by improving plant survival and promoting element phytostabilization or extraction under such harsh conditions. We isolated and characterised Pb and Cd-tolerant root-associated bacteria from Helianthus petiolaris growing on a Pb/Cd polluted soil in order to compose inoculants that can promote plant growth and also ameliorate the phytostabilization or phytoextraction efficiency. One hundred and five trace element-tolerant rhizospheric and endophytic bacterial strains belonging to eight different genera were isolated from the aromatic plant species Helianthus petiolaris. Most of the strains showed multiple PGP-capabilities, ability to immobilise trace elements on their cell wall, and promotion of seed germination. Bacillus paramycoides ST9, Bacillus wiedmannii ST29, Bacillus proteolyticus ST89, Brevibacterium frigoritolerans ST30, Cellulosimicrobium cellulans ST54 and Methylobacterium sp. ST85 were selected to perform bioaugmentation assays in greenhouse microcosms. After 2 months, seedlings of sunflower (H. annuus) grown on polluted soil and inoculated with B. proteolyticus ST89 produced 40% more biomass compared to the non-inoculated control plants and accumulated 20 % less Pb and 40% less Cd in the aboveground plant parts. In contrast, B. paramycoides ST9 increased the bioaccumulation factor (BAF) of Pb three times and of Cd six times without inhibiting plant growth. Our results indicate that, depending on the strain, bioaugmentation with specific beneficial bacteria can improve plant growth and either reduce trace element mobility or enhance plant trace element uptake. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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14 pages, 1328 KiB  
Article
Assessment and Mapping of Soil Salinization Risk in an Egyptian Field Using a Probabilistic Approach
by Sameh M. Shaddad, Gabriele Buttafuoco and Annamaria Castrignanò
Agronomy 2020, 10(1), 85; https://doi.org/10.3390/agronomy10010085 - 7 Jan 2020
Cited by 17 | Viewed by 2864
Abstract
The assessment of soil salinization risk at the field scale requires modeling of the spatial variability of soil salinity. This paper presents a probabilistic approach to estimate and map a risk index using all available auxiliary information. A probabilistic methodology is proposed to [...] Read more.
The assessment of soil salinization risk at the field scale requires modeling of the spatial variability of soil salinity. This paper presents a probabilistic approach to estimate and map a risk index using all available auxiliary information. A probabilistic methodology is proposed to estimate the conditional probability of exceeding the assigned threshold value of a generic indicator of soil salinity. A geostatistical non-parametric technique, probability kriging, was used to assess the risk of soil salinization and delineate different hazard zones within a field. The technique relies on indicator coding of information. The approach was applied to soil electrical conductivity measurements collected in an experimental field located in the Nile Delta region in Egypt, and submitted over time to trials with different fertilization treatments. The application of the method allowed delineation of a north-eastern zone in the field with a high risk of soil salinization due to its lack of cultivation for a long time and nearness to buildings that prevent water infiltration. The method proved to be quite promising from the perspective of precision agriculture and it is easily extendable to any sort of remote and proximal sensing auxiliary information, including information on the deepest layers of soil. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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Review

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22 pages, 1561 KiB  
Review
Biofuel Production with Castor Bean: A Win–Win Strategy for Marginal Land
by Linda Carrino, Donato Visconti, Nunzio Fiorentino and Massimo Fagnano
Agronomy 2020, 10(11), 1690; https://doi.org/10.3390/agronomy10111690 - 31 Oct 2020
Cited by 30 | Viewed by 9034
Abstract
The urgency to reduce resource depletion and waste production is expected to lead to an economy based on renewable resources. Biofuels, for instance, are a great green alternative to fossil fuel, but they are currently derived from edible vegetable oils such as soybean, [...] Read more.
The urgency to reduce resource depletion and waste production is expected to lead to an economy based on renewable resources. Biofuels, for instance, are a great green alternative to fossil fuel, but they are currently derived from edible vegetable oils such as soybean, palm, and sunflower. Concerns have been raised about the social–economic implication and ecological impacts of biodiesel production. Cultivating new lands as biodiesel feedstock rather than food supply, with the consequent increase in food prices, leads to so-called indirect land-use change (ILUC). Establishing bioenergy crops with phytoremediation ability on contaminated soils offers multiple benefits such as improving soil properties and ecosystem services, decreasing soil erosion, and diminishing the dispersion of potentially toxic elements (PTEs) into the environment. Castor bean is an unpalatable, high-biomass plant, and it has been widely demonstrated to possess phytoremediation capability for several PTEs. Castor bean can grow on marginal lands not suitable for food crops, has multiple uses as a raw material, and is already used in biodiesel production. These characteristics make it perfect for sustainable biodiesel production. Linking biofuel production with environmental remediation can be considered a win–win strategy. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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14 pages, 256 KiB  
Review
Agronomic Approaches for Characterization, Remediation, and Monitoring of Contaminated Sites
by Massimo Fagnano, Donato Visconti and Nunzio Fiorentino
Agronomy 2020, 10(9), 1335; https://doi.org/10.3390/agronomy10091335 - 5 Sep 2020
Cited by 19 | Viewed by 3182
Abstract
With a view to conserving or improving soil ecosystem services, environment-friendly techniques, such as bio- and phytoremediation, can effectively be used for the characterization, risk assessment, and remediation of contaminated agricultural sites. Polyannual vegetation (meadows, poplar, and cane stands) is widely considered the [...] Read more.
With a view to conserving or improving soil ecosystem services, environment-friendly techniques, such as bio- and phytoremediation, can effectively be used for the characterization, risk assessment, and remediation of contaminated agricultural sites. Polyannual vegetation (meadows, poplar, and cane stands) is widely considered the most efficient tool for remediation (extraction of bioavailable fraction of contaminants), for undertaking safety measures (reducing the mobility of contaminants towards other environmental compartments), and for restoring the ecosystem services of contaminated agricultural sites (biomass production, groundwater protection, C storage, landscape quality improvement, and cultural and educational services). The roles of agronomic approaches will be reviewed by focusing on the various steps in the whole remediation process: (i) detailed environmental characterization; (ii) phytoremediation for reducing risks for the environment and human health; (iii) agronomic management for improving efficiency of phytoremediation; and (iv) biomass recycling in the win-win perspective of the circular economy. Full article
(This article belongs to the Special Issue Agronomic Approaches for Remediation of Contaminated Soils)
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