Biochar and alternate partial root-zone irrigation greatly enhance the effectiveness of mulberry in remediating lead-contaminated soils

Abstract Aims Soil lead contamination has become increasingly serious and phytoremediation can provide an effective way to reclaim the contaminated soils. This study aims to examine the growth, lead resistance and lead accumulation of mulberry (Morus alba L.) seedlings at four levels of soil lead contamination with or without biochar addition under normal or alternative partial root-zone irrigation (APRI). Methods We conducted a three-factor greenhouse experiment with biochar (with vs. without biochar addition), irrigation method (APRI vs. normal irrigation) and four levels of soil lead (0, 50, 200 and 800 mg·kg−1). The performance of the seedlings under different treatments was evaluated by measuring growth traits, osmotic substances, antioxidant enzymes and lead accumulation and translocation. Important Findings The results reveal that mulberry had a strong ability to acclimate to soil lead contamination, and that biochar and APRI synergistically increased the biomass and surface area of absorption root across all levels of soil lead. The seedlings were able to resist the severe soil lead contamination (800 mg·kg−1 Pb) by adjusting glutathione metabolism, and enhancing the osmotic and oxidative regulating capacity via increasing proline content and the peroxidase activity. Lead ions in the seedlings were primarily concentrated in roots and exhibited a dose–effect associated with the lead concentration in the soil. Pb, biochar and ARPI interactively affected Pb concentrations in leaves and roots, translocation factor and bioconcentration. Our results suggest that planting mulberry trees in combination with biochar addition and APRI can be used to effectively remediate lead-contaminated soils.

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Role of Two Plant Growth-Promoting Bacteria in Remediating Cadmium-Contaminated Soil Combined with Miscanthus floridulus (Lab.)

Plants ◽

10.3390/plants10050912 ◽

2021 ◽

Vol 10 (5) ◽

pp. 912

Author(s):

Shuming Liu ◽

Hongmei Liu ◽

Rui Chen ◽

Yong Ma ◽

Bo Yang ◽

...

Keyword(s):

Plant Growth ◽

Contaminated Soils ◽

Translocation Factor ◽

Plant Growth Promoting Bacteria ◽

Bacterial Strains ◽

Pgp Traits ◽

Cd Tolerance ◽

Plant Growth Promoting ◽

Growth Promoting ◽

Cd Translocation

Miscanthus spp. are energy plants and excellent candidates for phytoremediation approaches of metal(loid)s-contaminated soils, especially when combined with plant growth-promoting bacteria. Forty-one bacterial strains were isolated from the rhizosphere soils and roots tissue of five dominant plants (Artemisia argyi Levl., Gladiolus gandavensis Vaniot Houtt, Boehmeria nivea L., Veronica didyma Tenore, and Miscanthus floridulus Lab.) colonizing a cadmium (Cd)-contaminated mining area (Huayuan, Hunan, China). We subsequently tested their plant growth-promoting (PGP) traits (e.g., production of indole-3-acetic acid, siderophore, and 1-aminocyclopropane-1-carboxylate deaminase) and Cd tolerance. Among bacteria, two strains, Klebsiella michiganensis TS8 and Lelliottia jeotgali MR2, presented higher Cd tolerance and showed the best results regarding in vitro growth-promoting traits. In the subsequent pot experiments using soil spiked with 10 mg Cd·kg−1, we investigated the effects of TS8 and MR2 strains on soil Cd phytoremediation when combined with M. floridulus (Lab.). After sixty days of planting M. floridulus (Lab.), we found that TS8 increased plant height by 39.9%, dry weight of leaves by 99.1%, and the total Cd in the rhizosphere soil was reduced by 49.2%. Although MR2 had no significant effects on the efficiency of phytoremediation, it significantly enhanced the Cd translocation from the root to the aboveground tissues (translocation factor > 1). The combination of K. michiganensis TS8 and M. floridulus (Lab.) may be an effective method to remediate Cd-contaminated soils, while the inoculation of L. jeotgali MR2 may be used to enhance the phytoextraction potential of M. floridulus.

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The Influence of Crude Oil on Mechanistic Detachment Rate Parameters

Geosciences ◽

10.3390/geosciences8090332 ◽

2018 ◽

Vol 8 (9) ◽

pp. 332 ◽

Cited By ~ 10

Author(s):

Manar Hasan ◽

Abdul-Sahib Al-Madhhachi

Keyword(s):

Soil Moisture ◽

Soil Contamination ◽

Crude Oil ◽

Contaminated Soils ◽

Soil Stabilization ◽

Inverse Correlation ◽

Lead Contamination ◽

Contamination Level ◽

Model Parameters ◽

Wilson Model

Iraqi soil contamination greatly influenced soil detachment. Previous researchers have not been able to predict the influence of crude oil soil contamination on either the mechanistic dimensional detachment parameter b0 or the threshold parameter b1 of the mechanistic detachment model (Wilson model). The aims of this research were (1) to investigate the influence of crude oil on deriving Wilson model parameters, b0 and b1, with two setups at different scales and different soil moisture contents and (2) to predict b0 and b1 in crude oil contaminated dry soils with varying levels of contamination. The “mini” JET apparatus was implemented under laboratory conditions for soil specimens packed at both a small (standard mold) and a large (in-situ soil box) scale. The results showed an inverse correlation between b0 and water content for clean soil. No correlation between b0 and soil moisture content was observed for contaminated soils. There was a huge reduction in the b0 value as the contamination time increased compared to the clean soil. This was related to the role crude oil plays in soil stabilization. Crude oil contamination significantly increased lead contamination level while slightly increasing the pH and total organic carbon. The influence of crude oil on mechanistic soil detachment can be predicted with a priori JET experiments on soils without crude oil based on crude oil parameters.

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Accumulation and transport of antimony and arsenic in terrestrial and aquatic plants in an antimony ore concentration area (south-west China)

Environmental Chemistry ◽

10.1071/en20003 ◽

2020 ◽

Vol 17 (4) ◽

pp. 314

Author(s):

Ling Li ◽

Lu Liao ◽

Yuhong Fan ◽

Han Tu ◽

Shui Zhang ◽

...

Keyword(s):

Plant Species ◽

Contaminated Soils ◽

Inductively Coupled Plasma ◽

Translocation Factor ◽

Pueraria Lobata ◽

West China ◽

Inductively Coupled ◽

South West ◽

High Concentrations ◽

Preferred Species

Environmental contextPhytoremediation requires an understanding of bioconcentration and translocation processes that determine behaviour and fate of potentially toxic elements. We studied the distribution of antimony and arsenic in terrestrial and aquatic soil-plant systems in an antimony ore zone. We found that the common climbing plant Kudzu (Pueraria lobata) is suitable for phyto-stabilisation of antimony-bearing tailings, while tiger grass (Thysanolaena maxima) was able to extract antimony and arsenic from contaminated soils. AbstractAntimony (Sb) pollution is a major environmental issue in China. Many historical abandoned tailings have released high concentrations of Sb and its associated element arsenic (As) to surrounding environments. This has prompted the need to understand accumulation and translocation processes that determine the behaviour and fate of Sb and As in contaminated soil–plant systems and to identify suitable plant species for phytoremediation. Here we investigate distribution of Sb and As in terrestrial and aquatic dominant plant species and associated soils, all of which are naturally found in an Sb ore concentration area in south-west China. Total Sb and As concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). The percentage of soluble Sb and As in the total concentrations were determined; the results showed that the basic soil environment facilitates the release of Sb and As from contaminated soils, and that Sb has higher mobility than As. Bioconcentration factor (BCF) and translocation factor (TF) were used for evaluating the ability of plants to accumulate and transport Sb and As, respectively. The results indicated that all selected plant species have the potential to tolerate high concentrations of Sb and As. Consequently, this study suggested that Pueraria lobata (PL) can be used as the preferred species for phytostabilisation of abandoned Sb-bearing tailings, given that PL has well-developed roots and lush leaf tissues and the ability to translocate Sb from roots to aboveground parts. Thysanolaena maxima (TM) is suitable for phyto-extraction of Sb and As in contaminated soils.

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Effects of Ectomycorrhizal Fungi and Heavy Metals (Pb, Zn, and Cd) on Growth and Mineral Nutrition of Pinus halepensis Seedlings in North Africa

Microorganisms ◽

10.3390/microorganisms8122033 ◽

2020 ◽

Vol 8 (12) ◽

pp. 2033

Author(s):

Chadlia Hachani ◽

Mohammed S. Lamhamedi ◽

Claudio Cameselle ◽

Susana Gouveia ◽

Abdenbi Zine El Abidine ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

North Africa ◽

Mineral Nutrition ◽

Contaminated Soils ◽

Mycorrhizal Fungi ◽

Pinus Halepensis ◽

Translocation Factor ◽

Contaminated Sites ◽

High Concentrations

The pollution of soils by heavy metals resulting from mining activities is one of the major environmental problems in North Africa. Mycorrhizoremediation using mycorrhizal fungi and adapted plant species is emerging as one of the most innovative methods to remediate heavy metal pollution. This study aims to assess the growth and the nutritional status of ectomycorrhizal Pinus halepensis seedlings subjected to high concentrations of Pb, Zn, and Cd for possible integration in the restoration of heavy metals contaminated sites. Ectomycorrhizal and non-ectomycorrhizal P. halepensis seedlings were grown in uncontaminated (control) and contaminated soils for 12 months. Growth, mineral nutrition, and heavy metal content were assessed. Results showed that ectomycorrhizae significantly improved shoot and roots dry masses of P. halepensis seedlings, as well as nitrogen shoot content. The absorption of Pb, Zn, and Cd was much higher in the roots than in the shoots, and significantly more pronounced in ectomycorrhizal seedlings—especially for Zn and Cd. The presence of ectomycorrhizae significantly reduced the translocation factor of Zn and Cd and bioaccumulation factor of Pb and Cd, which enhanced the phytostabilizing potential of P. halepensis seedlings. These results support the use of ectomycorrhizal P. halepensis in the remediation of heavy metal contaminated sites.

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Response of Corchorus olitorius Leafy Vegetable to Cadmium in the Soil

Plants ◽

10.3390/plants9091200 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1200

Author(s):

Sibongokuhle Ndlovu ◽

Rajasekhar V.S.R. Pullabhotla ◽

Nontuthuko R. Ntuli

Keyword(s):

Contaminated Soils ◽

Translocation Factor ◽

Reproductive Traits ◽

Leafy Vegetable ◽

Leafy Vegetables ◽

Corchorus Olitorius ◽

Cd Accumulation ◽

Cd Toxicity ◽

Morphological Alterations ◽

Hormetic Effect

Corchorus olitorius, a leafy vegetable with high nutrient content, is normally collected from the wild, in areas that are prone to cadmium (Cd) toxicity. However, studies on how Cd accumulation affects vegetative and reproductive traits of leafy vegetables in South Africa are limited. Therefore, this study tested the effect of Cd accumulation on C. olitorius morphological traits. Plants were grown under various Cd concentrations and studied for variation in vegetative and reproductive traits as well as accumulation in roots and shoots. Plants exposed to 5 mg/kg Cd had longer roots with higher moisture content, heavier fresh and dried stems, as well as dried leaves, which indicated a hormetic effect in C. olitorius after exposure to low Cd concentration in the soil. Again, plants treated with 5–10 mg/kg Cd, accumulated toxic (>10 mg/kg dry weight) Cd within shoots and roots, with minor morphological alterations. Plants could survive, with some morphological defects, Cd toxicity up to 20 mg/kg in soil. Only plants exposed to 5 mg/kg could reproduce. Cd accumulation increased with an increase in the soil, with higher accumulation in shoots. The translocation factor was high (>1) in all Cd concentrations. In conclusion, C. olitorius can accumulate toxic Cd, and yet grow and reproduce either normally or better than the control. The proposed dose of Cd that induces hormesis in C. olitorius is 5 mg/kg in the soil. Therefore, C. olitorius is suitable for phytoremediation of Cd contaminated soils, but unsafe for consumption when it grows in such areas.

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Soil lead bioavailability and in situ remediation of lead-contaminated soils: A review

Environmental Progress ◽

10.1002/ep.10004 ◽

2004 ◽

Vol 23 (1) ◽

pp. 78-93 ◽

Cited By ~ 121

Author(s):

Ganga M. Hettiarachchi ◽

Gary M. Pierzynski

Keyword(s):

Contaminated Soils ◽

In Situ Remediation ◽

Soil Lead

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Effect of Lime and Farmyard Manure on the Concentration of Cadmium in Water Spinach (Ipomoea aquatica)

ISRN Agronomy ◽

10.5402/2012/719432 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Subash Chandra Shaha ◽

Md. Abul Kashem ◽

Khan Towhid Osman

Keyword(s):

Contaminated Soils ◽

Growth Parameters ◽

Sandy Loam ◽

Farmyard Manure ◽

Cadmium Concentration ◽

Water Spinach ◽

Cd Uptake ◽

Ipomoea Aquatica ◽

Loam Soil ◽

Four Levels

An experiment was conducted to investigate the effect of lime and farmyard manure on the concentration of cadmium in water spinach. Water spinach (Ipomoea aquatica cv. Kankon) was grown in sandy loam soil spiked with 5 mg Cd with lime (L) and farmyard manure (M) amendments. The treatments consisted of control, four levels of L (5, 10, 15, and 20 t ), M (5, 10, 15, and 20 t ), and their combinations (55, 1010, 1515, and 2020 t ). Growth parameters of water spinach increased significantly with the addition of lime and farmyard manure in the soil. Lime addition to soil decreased Cd concentration in both shoot and root of water spinach. In control (00), Cd concentration was 62.67 mg in shoot, and 135.5 mg in root. Cadmium concentration decreased by 72, 15, and 66% over the control in shoot and 82, 28, and 76% in the roots correspondingly with the highest rate of lime (20 t ), manure (20 t ), and lime plus manure combinations (20 t 20 t ). The results imply that 5 to 10 t lime could be used in Cd-contaminated soils to reduce Cd uptake by agricultural crops.

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Effect of Exterior Home Renovation on Community Lead Hazards: A Pilot Study in South Bend, Indiana

10.26434/chemrxiv-2021-sj4p5 ◽

2021 ◽

Author(s):

Kyle Moon ◽

Meghanne Tighe ◽

Joshua Brooks ◽

J. Mike Coman ◽

Heidi Beidinger-Burnett ◽

...

Keyword(s):

Lead Level ◽

Bare Soil ◽

Soil Samples ◽

Lead Contamination ◽

Soil Lead ◽

Lead Paint ◽

The Us ◽

Lead Levels ◽

South Bend ◽

Lead Hazards

Communities across the US face challenges from legacy lead contamination. In South Bend, Indiana, over 68,000 homes were built before 1978, and most contain leaded paint. When these homes are repainted, repaired, or renovated, failure to use lead-safe practices can contaminate the surrounding soil with lead paint flakes and dust. In this study, we used X-ray fluorescence (XRF) to measure soil lead levels surrounding a home with exterior leaded paint (about 10% Pb w/w) after it was repainted in fall of 2019. The painted wooden exterior was prepared for painting by dry scraping without the use of tarps or plastic barriers. A total of 220 soil samples were collected from the home and its immediate neighbors, and an additional 102 samples were collected from 34 homes in the same neighborhood. The median lead level in dripline soil samples across the neighborhood was 434 ppm, but in the recently repainted house, the median soil lead was 1808.9 ppm, and it was 1,346.4 ppm in the four neighboring homes. The repainted house and its four neighbors were mulched by covering all bare soil to a 4-6 inch depth with chipped wood mulch. Two months later, another 100 soil samples were collected and analyzed. The surface lead level around the target house dropped to 13.8 ppm, showing that mulching is an effective strategy for interim control of high soil lead levels.

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Field and Modeling Study on Saving Mineral Fertilizers, Increasing Farm Income and Improving Soil Fertility Using Bio-Irrigation with Drainage Water from Fish Farms

Water ◽

10.3390/w12112998 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2998

Author(s):

Abdelraouf R. E. ◽

Ayman El-Sayed ◽

Ibrahim A. Alaraidh ◽

Abdulaziz Alsahli ◽

Mohamed El-Zaidy

Keyword(s):

Irrigation Water ◽

Root Zone ◽

Water Productivity ◽

Nitrogen Concentration ◽

N Uptake ◽

Soil Layer ◽

Farm Income ◽

Mineral Fertilizers ◽

Additional Amount ◽

Four Levels

The reuse of new and non-traditional sources of water for the purpose of irrigation is the primary goal of all countries that are located in dry areas and suffer from water scarcity, including Egypt in particular. This study was conducted to determine the appropriateness and quantify the benefits of using fish farm wastewater (DWFF), as an alternative to fresh irrigation water (IW), for the irrigation of barley. Two types of water quality were tested for the irrigation of barley, namely DWFF and IW, in addition to four levels of fertilization rates, 100%N, 80%N, 60%N, and 40%N, where 100%N represents 156 kg of nitrogen per hectare. The results showed a positive effect of increasing the nitrogen fertilization rate with irrigation water on the crop with the use of DWFF and IW for irrigating barley in two seasons: 2017/2018 and 2018/2019. The yield when using DWFF for the irrigation of barley was higher than the yield when using IW, which was in the range of 5.1% and 25.9% in 2017/2018 and between 9.8% and 33.3% in 2018/2019. This was due to the additional amount of dissolved biological nitrogen and other nutrients contained in DWFF. Notably, an additional amount of dissolved nitrogen is inherent in DWFF (12.81 kg nitrogen ha−1 in 2017/2018 and 12.43 kg nitrogen ha−1 in 2018/2019) and other elements, such as phosphorus and potassium, which are two macronutrients for crops. The SALTMED model was used to simulate soil moisture content, water application efficiency, nitrogen concentration in the soil layer in the effective root zone, N uptake, the dry matter of grown barley, and yield and water productivity for all treatments, with R2 values of 0.94, 0.89, 0.99, 0.916, 0.89, 0.915, and 0.919 respectively. The research concluded that the use of DWFF is an effective alternative to IW for irrigating barley. It also helped to achieve higher yields while applying lower amounts of IW and chemical fertilizers. There are also additional benefits, such as reducing the drainage to the drainage network and increasing the income of farmers.

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Bioavailability and geochemical forms of Pb and Zn in Kosovo contaminated soils

10.5194/egusphere-egu21-7649 ◽

2021 ◽

Author(s):

Teodoro Miano ◽

Donato Mondelli ◽

Lea Piscitelli ◽

Hana Voca ◽

Valeria D'Orazio

Keyword(s):

Contaminated Soils ◽

Agricultural Soils ◽

Translocation Factor ◽

Total Content ◽

Heavy Metal Accumulation ◽

Pot Experiment ◽

Residual Fraction ◽

Cultivated Plants ◽

Exchangeable Fraction ◽

Mn Oxides

Mitrovica area (northern Kosovo) presents contamination by PTE in agricultural soils caused by smelter emissions and their transfer and accumulation in cultivated plants. Soil A and B, sampled from two sites in Mitrovica municipality, showed a total content of Pb and Zn of 2153 and 3087 mg kg-1, and 3214 and 4619 mg kg-1. A pot experiment was performed to understand the phytoremediation potential of two non-food crops (Sorghum bicolor L. Moench and Brassica napus Westar), chosen for their economic importance and heavy metal accumulation capacities. Bioconcentration factor, translocation factor and tolerance Indexes clearly indicated a better performance of canola in tolerating Pb and Zn, especially in soil B, even if contained higher amounts of both metals. To evaluate different chemical and physical forms of Pb and Zn in the two soils, a modified BCR extraction scheme was employed to determine amounts bound to different soil components: exchangeable fraction (acid-soluble, carbonate and exchangeable bound), reducing fraction (metal bound to Fe- or Mn-oxides), oxidizable fraction (organic and sulphide bound), and residual fraction (strongest binding with crystalline structure). A comparison of the sum of Pb and Zn concentrations obtained from BCR relative to total digestion values (pseudo-total concentrations) showed recoveries close to 100%. Very small amounts of Pb were released during step 1 (exchangeable fraction) (6,86% - soil A and 2,12% - soil B). The highest concentration of Pb, 62,62% in soil A and 56,68% in soil B, decreased in the reducing fraction (step 2), probably occurring mainly as forms bound to Fe/Mn oxides. Step 3 (oxidizable-organic matter &#8220;OM&#8221; and sulphides) released amounts of 23,15% and 20,32% of total Pb in soil A and B. Residual fraction presented very different amounts of Pb (7,87% in soil A and 20,88% in soil B). Unlike Pb, no important differences were found in the distribution of Zn among the various fraction of the two soils, with the greater amounts contained in the exchangeable fraction of both soils, 31.11% in soil A and 21.92% in soil B. Very small amounts of Zn were released during step 2 (19,3% in soil A and 22,27% in soil B) whereas step 3 released the highest amounts of Zn in both soils (36,56% in A and 40,17% in B). Residual fraction presents similar amounts of total Zn, 13,03% in A e 15,64% in B, showing an opposite trend with respect to Pb. So, a major portion of total Pb was associated to the reducing fraction, while Zn was found mostly in oxidable one, indipendent on the origin of samples. Pb strongly interacts with Fe-/Mn oxides, and, in soil B, a greater amount is immobilized in the residual fraction. These results suggest lower mobility and bioavailability of Pb in soil B with respect to soil A, partially explaining the pot experiment.

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