Qualità ambientale e fitodepurazione: bonifica dei suoli e delle acque

Qualità del suolo e salute

Soil quality Plants, anim Ils and human health Environmental Quality Water qualityA F O FAN Food and Agriculture Organization of the United Nations

Inquinamento del suolo: una realtà nascosta

SOIL POLLUTION: AHIDDEN REALITY FAO, Rome, 2018 GLOBAL SOIL PARTNERSHIP http://www.fao.org/3/i9183en/i9183en.pdf

Contaminazione della catena alimentare

2.1 |SOIL POLLUTION, PLANT UPTAKE AND FOOD CHAIN CONTAMINATION The pathways of contamination within the food chain by the transfer of soil pollutants through plants are shown in Figure 14.

Evaporation and volatilization from leaf Gaseous deposition to leaf via cuticle and stomata 0 Dry and wet deposition of particles followed by deposition into leaf Transport in the transpiration stream within the xylem Suspension of soil particles by wind and rain Direct contact uptake from soil surface to roots Volatilization from sail Desorption from sail followed by root uptake from soil solution

Figure 14. Principal uptake pathways for the uptake of soil contaminants by plants (adapted from Collins. Fryer and Grosso. 2006)SOIL: from sink to source for contaminants CONTAMINAT CoolCtips. com

Bombe chimiche a orologeria nel suolo

CHEMICAL TIME BOMBS soils loaded with contaminants become chemical time bombs --- - -A chemical time bomb may prime when a toxic chemical is mobilized because the capacity of the blocking sink is: a) Overwhelmed by an excessive load of contaminant 0 0 0 b) Diminished due to environmental changes influencing those parameters controlling the capacity of the sink.

Cambiamenti ambientali e capacità del suolo

Fattori che influenzano la capacità del suolo

Environmental changes affecting the capacity of the sink Soil use 0 0 Soil redox potential Soil moisture Soil organic matter Soil temperature Soil biodiversity Soil-plants interaction Soil pH

Cambiamenti climatici e mobilitazione degli inquinanti

Climate changes can become the trigger for a number of environmental time bombs Climate Change Temperate Rainfall Hydrological balance Annual/seasonal Microbial Processes Soil Moisture Leaching rate Organic matter Nitrification Irrigation Soil structure CEC PH Redox Salinization pH Mobilization of stored pollutants in soils and wetlands

Figure 1. Schematic interlinkage between climate change and processes affecting the mobilization of stored pollutants in soils and wetlands. (Source: Stigliani and Salomons (1991)

Origine della contaminazione del suolo

Origin of soil contamination - Natural sources - Agriculture - Industry - Urban activities - Mining - Waste disposal - Accidental spills and leaks

Fonti di contaminazione: diffuse e puntuali

Diffuse sources: often low-medium concentrations, but affecting wide areas Punctual sources: localized; often hotspots with high concentrations

Esempi di contaminanti del suolo

Contaminanti inorganici

-Examples of soil contaminants Inorganic: · Toxic metals (heavy metals) and metalloids · Strong acids and alkali · Radionuclides · Toxic inorganic compounds · Non-toxic elements, but with potential adverse environmental effects (e.g., eutrophicants) • ...

Contaminanti organici

Organic: · Hydrocarbons (e.g., PAH: polycyclic aromatic hydrocarbons) • Solvents · Dyes · Dioxin · Pesticides and herbicides • ....

Sovraccarico di elementi non tossici

Overload with non-toxic elements Even non-toxic elements can represent environmental threats when an environmental system is overloaded with them. A typical example is represented by eutrophication of surface waters overloaded with N and P transferred from soils.

210 197.19 200 200.522 190.732 190 193.882 183.175 MILLION MT 186.895 180 176.784 180.079 170 170.845 161.829 160 161.659 150 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

Figure 6. Global synthetic fertilizers consumption. Source: FAO, 2015a

Buffer strips protecting surface waters from agricultural derived contamination

Strategie di gestione dei contaminanti

Fattori per la scelta della strategia

Choice of contaminant management strategy The choice depends on: - Type of contaminant(s) Toxicity Biogeochemical reactions - Characteristics of the site (location, land use, ... ) - Contaminant origin - Contaminant concentration - Contaminant mobility - Overall risk - Sustainability of the intervention

Opzioni per la gestione dei suoli contaminati

-Some options for contaminated soils management Stabilization Contaminant mobility is limited by artificial or natural barriers (e.g., immobilization in manufactured structures; biostabilization, phytostabilization; ... ) Attenuation e.g., monitored natural attenuation: natural mechanisms of soil cleanup are active in the site and their effects are monitored Remediation The contaminated soil is treated in the same place (in situ) or elsewhere (ex situ). Examples may range from soil removal and disposal, to chemical or physical remediation strategies, to bioremediation (including phytoremediation)

There are several methods available for managing contaminated soils

Esempi di siti contaminati

La cava di Balangero negli anni '50 Cava di Balangero Sardegna Rio Tinto, Spagna

Fitodepurazione

Funzionamento della fitodepurazione

Phytoremediation Plants (herbaceous, shrubs, trees) can be useful to enhance the decontamination of polluted soils and watrbodies, or to reduce the health risks related to the presence of the contaminants. According to the type of contamination, choice of plant species and site management, we can pursue different objectives and reach different results using plants for site remediation

Azione delle piante sui contaminanti

Action on contaminant Contaminant Type Management Phytoextraction Removed Inorganic Periodic harvest Phytovolatilization Removed Inorganic and organic Permanent Phytodegradation Attenuated in situ Organic Permanent Phytostabilization Immobilized in situ Inorganic and organic Permanent Helianthus annus

Piante ornamentali per la fitodepurazione di composti organici

Tab. 3 - Ornamental plants for the phytoremediation of organic compounds. (B[a]P): benzo[a]pyrene; (DDT): dichlorodiphenyltrichloroethane; (HCH): hexachlorocyclohex- ane; (PCB): polychlorinated biphenyls; (PAH): polycyclic aromatic hydrocarbons; (TCE): trichloroethylene; (TPH): total petroleum hydrocarbons.

Group Species Pollutants References Itea virginica Oryzalin Baz & Fernandez 2002 Populus deltoides x nigra TCE Doty et al. 2017 Dioxane Aitchison et al. 2000 PCB Liu & Schnoor 2008 Trees Atrazine Burken & Schnoor 1997 Populus hybrids HCH Bianconi et al. 2011 Salix alba Oryzalin Baz & Fernandez 2002 Salix miyabeana PAH, PCB Guidi et al. 2012 Salix sachalinensis PAH, PCB Guidi et al. 2012 Cytisus striatus HCH Becerra-Castro et al. 2013 Nerium oleander Fluoride Khandare et al. 2017 Ricinus communis DDT Huang et al. 2011 Aloe vera Formaldehyde Liu et al. 2007 Aster amellus Dyes Khandare et al. 2011 Canna indica Triazophos Cheng et al. 2007 Chrisanthemum morifolium Benzene, Liu et al. 2007 Formaldehyde Crassula portulacea Benzene Liu et al. 2007 Dianthus chinensis Sulfur dioxide Liu et al. 2007 Echinacea purpurea TPH Liu et al. 2012 Festuca arundinacea TPH Liu etal. 2012 Gaillardia aristata TPH Liu et al. 2012 Gaillardia grandiflora Dyes Chandanshive et al. 2018 Impatiens balsamina TPH Cai et al. 2010 Iris lactea TPH Cheng et al. 2017 Medicago sativa TPH Liu et al. 2012 Mirabilis jalapa B[a]P Sun & Zhou 2016 Portulaca grandiflora Dyes Chandanshive et al. 2018 Portulaca oleracea Fluoride Khandare et al. 2017 Tagetes patula Dyes Chandanshive et al. 2018 B[a]P Sun & Zhou 2016 Phytovolatilization Phytodegradation Phytoextraction A Pollutants . Organic compounds Shrubs Phytostabilization Phytostimulation Rhizo iltration Capuana, 2020 https://iforest.sisef.org/pdf/?id=ifo r3242-013 Herbaceous

Vantaggi e svantaggi della fitodepurazione

Vantaggi

Advantages · Low interference with ecosystems · Relatively low costs of plantation · Low cost and labour for maintenance (except phytoextraction) · Large sites can be treated · In some case possible reuse of plant material · Fruibility of the area during remediation · Social acceptance

Svantaggi

Disadvantages · Suitable for relatively low concentrations · Shallow localization of contaminants; phytoaccessibility · Remediation can take long time (decades, centuries) · Plant materials with contaminants must be managed · Possible dispersion of the contaminants with plant tissues (eg., leaves) · Possible passage to the foodchain (animal grazing)

Scelta delle specie vegetali per la fitodepurazione

Choice of the plant species for pohytoremediation • Nature of the contaminant(s) • Level, localization and extension of the contamination · Characteristics of the site (hurban, extrahurban, accessibility to people/animals) · Objective of the remediation action (immobilization, extraction, degradation) · Root depth and extension · Characteristics of the soil (pH, texture, water content .. ) · Climate

Piante iperaccumulatrici di metalli pesanti

Alcune piante iperaccumulatrici di metalli pesanti (Ni, Cd, Cr, etc) Alyssum bertolonii Brassica juncea Thlapsicaerulescens Thlapsi sylvium

Fitostabilizzazione naturale

Mining area of Crocette, Anzasca Valley, Italy: natural phytostabilization Mining dumps with As and cyanide P1 Arsenic concentration in soil (mg/kg) 1 C1 1 C2 0 10000 20000 P2 Arsenic concentration in soil (mg/kg) 2 A 2 C1 2 C2 0 5000 10000 15000 20000 25000

Riferimenti legislativi per la gestione dei siti contaminati

Riferimento legislativo per la gestione di siti contaminati: D.L. 3 aprile 2006, n. 152 (e successivi aggiornamenti) Norme in materia ambientale https://www.gazzettaufficiale.it/atto/serie generale/caricaDettaglioAtto/originario?atto.dataPubbl icazioneGazzetta=2006-04-14&atto.codiceRedazionale=006G0171 Decreto Terre e Rocce da Scavo D.P.R. 13 giugno 2017, n. 120 https://www.gazzettaufficiale.it/eli/id/2017/08/07/17G00135/sg DECRETO LEGISLATIVO 29 aprile 2010, n.75 - Riordino e revisione della disciplina in materia di fertilizzanti, a norma dell'articolo 13 della legge 7 luglio 2009, n. 88 https://www.politicheagricole.it/flex/cm/pages/ServeBLOB.php/L/IT/IDPagina/10087 LEGGE 14 gennaio 2013, n. 10 - Norme per lo sviluppo degli spazi verdi urbani https://www.gazzettaufficiale.it/eli/id/2013/02/01/13G00031/sg

Bibliografia

Bibliografia: ISPRA/APAT - Manuale per le indagini ambientali nei siti contaminati http://www.isprambiente.gov.it/it/pubblicazioni/manuali-e-linee-guida/manuale-per-le- indagini-ambientali-nei-siti ISPRA-Ambiente, Paesaggio e Infrastrutture. Volume I 65/2010 ISBN: 978-88-448-0471-8 • Ambiente, Paesaggio e Infrastrutture. Volume I. Presentazione · 65.1 Interazione fra infrastrutture lineari e patrimonio geologico (pdf - 3.87 mb) · 65.2 Linee guida per il trattamento dei suoli nei ripristini ambientali legati alle infrastrutture · 65.3 Analisi e progettazione botanica per gli interventi di mitigazione degli impatti delle infrastrutture lineari · 65.4 Mitigazioni a verde con tecniche di rivegetazione e ingegneria naturalistica nel settore delle strade · 65.5 L'inserimento paesaggistico delle infrastrutture stradali: strumenti metodologici e buone pratiche di progetto http://www.isprambiente.gov.it/it/pubblicazioni/manuali-e-linee-guida/ambiente-paesaggio-e- infrastrutture-volume-1