Castro, Paula M. L.

Marques, Ana P. G. C.

Paulo, Ana M.

English

Repositório Institucional da Universidade Católica Portuguesa

Microbiota-assisted Phytoremediation of Metal Contaminated Soils by Sunflower08 de Abril de 2019Ana M. PauloPaula M.L. CastroAna P.G.C. Marques100 M ha of degraded/contaminated soils in the world (USEPA)Why a special concern with heavy metal contamination?Non degradable à we can only change their bioavailabilityOnly a few can be considered as nutrients for plants (ex. Zn) Hazardous to human health and the ecosystems in generalRecovery of contaminated soilsInternational laws (Netherlands, Germany, Canada, USA, European legislation)      impose limits to the contamination in soilPhysical and Chemical Treatments: expensive; may hinder soils for further applications; harmful for the existing animals and plantsWeatheringNatural occurrence of HM in soils (usually at low concentrations)Pedogenic processes on parent materialDust particles from rocks and volcanic ashBurning of fossil fuelsMining and smelting of oresMetallurgical industriesMunicipal waste and sewageFertilisers and pesticidesPersistent pollution of the soil with HMSoil washing 200 €/m3Soil vapour extraction 120 €/m3Soil flushing 145 €/m3Solidification 330 €/m3Stabilisation / Immobilisation 330 €/m3Vitrification 205 €/m3Electrokinetics 300 €/m3Thermal desorption 330 €/m3EncapsulationBiological treatments 90 to 200 €/m3Phytoremediation 30 €/m3Use of plants and associated microorganisms to treat the contaminated soilMAIN TECHNOLOGIES FOR THE REMEDIATION OF HM CONTAMINATED SOILSCHRONOLOGICAL DEVELOPMENTS OF PHYTOREMEDIATION OF HEAVY METAL CONTAMINATED SOILSADAPTED FROM STEPHENSON AND BLACK, 2014 UptakecontaminantcontaminantUptake:Plant roots take up HM and store them in the aboveground tissues: plant roots reduce the mobility of HM and avoid translocation to aboveground tissues; the use of soil amendments can be considered: HM taken up by the roots pass to the leaves and are volatilised through stomata where gas exchanges occur Chelate- enhancedHyperaccumulationPhytoextractionPhytostabilisationPhytovolatilisation (of volatile metals)PHYTOREMEDIATION OF METAL CONTAMINATED SOILS Relationship between Plants and MicroorganismsPlant growth under heavy-metal stress conditionsHormonal and nutritionimbalanceSusceptibility to diseasesDetrimental effect onplant growth anddevelopmentImprovement ofplant nutritionProduction ofgrowthregulatorsImprovement of plant tolerance to toxicsEnhancement of metal translocation or reduction of mobility/availability of metalsPlant Growth PromotingRhizobacteria (PGPR)Arbuscular mycorrhizalfungi (AMF)PHYTOREMEDIATION OF METAL CONTAMINATED SOILS - Use of different soils (contaminated with heavy metals) to grown crops withphytoremediation abilities- Application of selected bioinoculants- Determination of biometric parameters for the different plant sections- Heavy metal accumulation screening for the different plant sections- Assessment of the microbial dynamics and soil quality variationsObjectivesPrivate Property -Porto(Agricultural Soil -Control)Panasqueira Mine– Barroca Grande(Mine Soil)Chemical Complex -Estarreja(Industrial Soil)SoilsNo detectable CdZn at low levels (non phytotoxic)Private PropertyAgricultural Soil• Location: Porto• Biological agriculturalproductionSoilsParameter ValueCd (mg kg-1) <1.8 (L.O.D)Zn  (mg kg-1) 37± 3HM reach hazardous levelsZn and Cd appear as the main contaminantsEstarreja Chemical ComplexDischarge of solid residues directly to the soil in the surrounding areaConducting of the liquid effluents of the factories into the nearby watercoursesIndustrial Soil• Location: Estarreja (Aveirodistrict);• Chemical industries(production of sulphuric acid,production of chlorine andcaustic soda)SoilsParameter ValueCd (mg kg-1) 1.6 ± 0.5Zn  (mg kg-1) 599± 12Considered as concerning according tothe Ontario norms (>200 mg Zn/kg and >1.4 mg Cd/kg)Mine SoilHM reach hazardous levels in the surrounding soilsPanasqueira Mine – Barroca GrandeHuge tailing piles and two mud dams exposed to atmospheric conditions.Surface runoff and water percolation leach the tailings to Casinhas stream, which drains to Zêzere river.• Location: Beira Baixa (CasteloBranco district);• Covers an area of more than2000 ha;• Most important exploitations:Barroca Grande, Panasqueira,Rebordões and Vale da Ermida;• Economic exploitation mainlyfocused on wolframite,cassiterite and chalcopyrite.SoilsParameter ValueCd (mg kg-1) 9.7± 0.78Zn  (mg kg-1) 486± 15Considered as concerning according to the Ontario norms (>200 mg Zn/kg and >1.4 mg Cd/kg)Greenhouse preparationSoil collectionMINING INDUSTRIALCONTROL (AGRICULTURAL)Containers with 1 m3 lined with plastic and  perforated to allow water draining (soil capacity of 1 ton) SoilsMicroorganisms and plantsGrowth promotingrhizobacteria(Ralstonia eutropha1C2) Arbuscular mychorrizalfungi (Rhizophagusirregularis)•Isolated from a metal contaminated area•Capable of producing in vitro plant growth promoting substances• Capable of increasing sunflower biomass in vivoKnown for promoting plant growth and increasing the resistance of plants in stress conditionsSunflowerMiningseedsAMFBacteria1C2IndustrialseedsAgriculturalExperimental design6 monthsseedsAMFBacteria1C2DryingGrindingStorage*all plants growing in the Panasqueira mine soil died before harvestingBIOMASS =>  Agricultural > IndustrialResults: Plant Biomass and Microbial community  TreatmentBiomass (g)root stem flower seedsAgricultural 33.66 750.12 223.77 62.57Industrial 19.35 620.21 199.36 51.92-1C2 remained in the contaminated soil until the end of plant growth;-mychorrizal colonisation in all samples at harvest- Phytoremediation associated to PGPR induced an improvement of the microbial diversityACCUMULATION IN PLANTS => Agricultural (bellow phytotoxicity levels) < Industrial Industrial => Znroot, Znstem e Znflower > phytotoxic levels (100 mg/kg)Cdroot, Cdstem e Cdflower > phytotoxic levels (5mg/kg)Results: Metal levels in soils and plants at harvest  TreatmentZn (mg/kg dry weight) Cd (mg/kg dry weight)root stem flower seeds root stem flower seedsAgricultural 67 ± 3 A,c 56 ± 5 A,c 36 ± 11 A,b 2 ± 1 A,a ***F4,12=60,669 1.6 ± 0.2. A,b 1.0 ± 0.1. A,b 0 A,a 0 A,a***F4,12=11,193Industrial 434 ± 6 B,d 343 ± 9 B,c 129 ± 7 A,b 4 ± 2 A,a***F4,12=2418,33524 ± 2 B,d 15 ± 2 B,c 5.3 ± 0.6 B,b 0.5 ± 0.2 A,a***F4,12=141,505t=4,062 t=1,328 t=1,306 t=6,484 t=0,319 t=1,759 t= 14,545 t=16SOIL BIOAVAILABILITY=> Agricultural < Industrial => No Cd was detected as bioavailableZn (mg/kg) Cd (mg/kg)beginning harvest beginning harvestAgricultural 18.8 ± 0.70ª,B 25.2 ± 2.8ª,A n.d. n.d.Industrial 69.4 ± 1.5b,B 82.3 ± 6.3b,A n.d. n.d.Conclusions- Microbiota inoculated sunflower was capable of enduring the hazardous conditions installed and was able to produce significant levels of biomass - Inoculated microorganism were able to persist in a long term experiment and increase soil microbial quality - The metals were mainly accumulated in the root areas independently of the soil in which growth occurredPhytoremediation assisted by selected microbiota using energetic crops can be a solution with potential for the production of biomass for energy generationTHANK YOU FOR YOUR ATTENTION!Phytoenergy(PTDC/BTA-BTA/28761/2017)

Microbiota-assisted phytoremediation of metal contaminated soils by sunflower

https://repositorio.ucp.pt/bitstream/10400.14/42031/1/GWPSAR2022_presentation.pdf

Microbiota-assisted phytoremediation of metal contaminated soils by sunflower

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Repositório Institucional da Universidade Católica Portuguesa