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The main objectives of the first part of the research were: 1. To evaluate the potential of native vegetation for analysis of environmental risks due to soil contamination in industrial and agricultural contexts. 2. To study the potential of native plant species in extracting and accumulating soil PTEs from two contaminated sites. 3. To identify the extraction method that better represents the PTEs availability for plants by studying the relations between PTEs in the plants and total and bioavaila-ble PTEs content of soils. 4. To evaluate if some plant can be used as a bioindicator of PTEs bioavailability by studying the relationships between PTEs upake of different plant species and dif-ferent analytical methods for assessing PTEs bioavailability.. 5. To identify the probable origin of contaminants by analizing the soils of each plot using Hierarchical Cluster Analysis and Principle Component Analysis. In the second part of the research, two pots experiments were carried out by using industrial site sediments with the aim to evaluate the efficacy of different agro-nomical techniques of assisted phytoremediation (i.e. compost fertilization, biopromoters). The main objective of these pot experiment were the evaluation of the effects of organic amendment and commercial biopromoters on resistance of grass species to PTEs contami-nation and on PTEs phytoextraction/phytostabilization in a context aimed to reduce the environmental and sanitary risks of industrial contaminated sites by avoiding dispersion of contaminated soil particles. From the results of the three experiments described in this thesis, it’s possible to achieve the following conclusions. From the first experiment regarding the analysis of natural plants and soils for the charac-terization of two potentially contaminated sites, we concluded that: 1. Phytoscreening of native plants of polluted sites can be carried out to identify plant species that can tolerate very high PTEs concentrations and can be used for phy-toremediation. 2. Bioaccumulation coefficient of shoots (BACs), Bioaccumulation coefficient of roots (BACR) and a modified bioaccumulation coefficient (mBAC) that considers only the bioavailable fractions of contaminants (DTPA), can be used for assessing the relationships between weeds and the contaminants into the soil. 3. Artemisia vulgaris and Dittrichia viscosa in industrial site were able to transfer the potential bioavailable fraction of Pb to the aerial part and thus they could be con-sidered interesting candidates for phytoextraction; Epilobium tetragonum, Artemi-sia annua and Silene latifolia reported a high mBACR so they could be suitable for Pb phytostabilization. In the agricultural site, Cyperus rotundus showed the ability to transfer the potential bioavailable fraction of Cd to the aerial part, so it could be interesting for phytoextraction purpose while Cirsium arvense, Cynodon dactylon, Rumex sp., Piptatherum thomasii and Echium vulgare reported the ability to trans-fer Cd to the roots with a high mBACR so they could be suitable for Cd phytostabi-lization; 4. PCA and HCA can be used to identify the different PTE pollution sources. Princi-pal component analysis and hierarchical cluster analysis suggest that Pb, Cd, As, Cu and Zn seems form different pollution sources while Sb and Tl seems mainly of ge-ogenical origins. In the agricultural site, Cr and Cd are considered of anthropogenic origins while Pb, As and Zn mostly from geogenical origins; 5. It is possible to identify the extraction method that better represents the metal bio-availability and to know the relation between specific plant species and soil contam-ination. In the industrial site, only the Pb and Sb shoot concentrations well predict-ed by DTPA extraction. The ammonium nitrate extraction well predicted the shoot content of Pb, Sb, and Tl. The total soil PTEs content (TPTEs) were satisfactorily related to Sb and Tl shoot concentrations and in minor part to Pb. In agricultural site, TPTEs well predicted only the Zn shoot concentration. 6. Elymus. repens in industrial site can be used as indicator of soil Zn contamination while Lolium perenne in the agricultural site, can be used as indicator of As and Cd contamination. The second experiment, made on a potentially contaminated soil (Pb, Zn) allowed to get the following conclusions: 1. Application of compost and Biopromoters increased the plant growth, nutrient and Zn uptake; 2. The plant species used in this experiment resulted suitable for a phytostabilization purpose reducing the leaching of PTEs in the soil profile. Furthermore the biomass taken from the harvest can be used in no food chains and the complete coverage of the soil prevents the dispersion of the contaminated soil particles, thus allowing to reduce the risk for human health. The third experiment, made on a highly contaminated soil (Pb, Cd), allowed to get the fol-lowing conclusions: 1. The application of first dose of compost and biopromoters increased the growth, N uptake and Cd uptake; 2. The application of TA (consortium called “Panoramix” – Koppert b.v. ® containing Endomycorrhiza and Trichoderma species along with humic and fulvic acids) re-duced the bioavailable Pb as compared to control and to TB and reduced the bioa-vailable Pb from the initial conditions and the bare soil. 3. The combination of compost and biopromoters reduced the Cd soluble fraction as compared highlighting the importance of a vegetal soil cover for avoiding PTEs leaching in the soil profile. 4. The combination grass species-organic amendments-biopromoters can be successful-ly used in a phytoremediation project increasing the biomass production and PTEs uptake. The grass species can ensure the soil capping necessary for securing contam-inated sites, but also for improving soil structural aggregation that also prevents the dispersion of the contaminated soil particles. 5. The differences in the results between Pb and Zn in the second experiment and Pb and Cd in the third experiment highlighted the need to make preliminary studies to found the most suitable technique in relation to the specific contamination of a site.

In this work, a grass-based phytoremediation system integrated with an organic amendment and biostimulants was evaluated for remediating contaminated sites. Plant growth and biological fertility were monitored to assess the efficacy of a vegetative cap used as a safety measure to reduce sanitary and environmental risks of industrially contaminated soils and soil-washing sludges. Both matrices were potentially contaminated with Pb and Zn with an ecological risk index from low to moderate. According to potentially toxic elements (PTEs) bioaccessibility tests, the exposure to the released fine particulate matter may cause serious risks to human beings, in particular to children. The grass mixture was well adapted to both the substrates and a low PTEs mobility was detected, thus, reducing the leaching risk to ground water sources. Compost addition augmented significantly nitrogenase reductase (nifH) and ammonia monooxygenase (amoA) gene expression abundance in both substrates. Furthermore, a positive interaction between compost fertilization and a Trichoderma-based biostimulant inoculation was recorded in sludges resulting in a significant stimulation of nitrogen-fixing and ammonia-oxidizing bacteria. The application of compost and biostimulant increased soil fertility and plant growth. Furthermore, there was a slight reduction in PTE bioaccessibility, thus, improving the efficiency of the phytostabilization, limiting the resuspension and dispersion of the health-risk soil particulate.

The soil salinity increase in the Mediterranean basin is one of the consequences of the climate change. The aim of this study was to evaluate the adaptability of giant reed (Arundo donax L.) to salinity, in conditions of higher temperatures, in order to hypothesise the future use of giant reed under these conditions. The trial was carried out in pots under a permanent metal structure, open on the sides and with a clear PE on the top. Four levels of soil salinity in the range 3.3-15.5 dS m–1 were imposed. The stem number of the most stressed treatment was about 45% lower than the control and also the stem height was lower than in all other treatments. The green and yellow leaf number decreased as the soil salinity increased, and their sum was significantly lower in the two most stressed treatments. Osmotic potential of the leaf sap was not affected by salinity. Leaf water potential and stomatal conduc- conductance in the saline treatments were lower than in the control. tance Assimilation rate showed similar pattern of stomatal conductance. Intrinsic WUE remained almost stable until July and increased during August under the most stressful conditions. PSII photochemistry was not affected by soil salinity. Biomass yield was not different from the control until to soil ECe 12.0 dS m–1: only the most stressed treatment (15.5 dS m–1) caused yield losses (50%). Tolerance threshold to salinity was 11.2 dS m–1 and the relative yield losses were 11.6% per dS m–1.

The results of experiments carried out in the National Interest Priority Site (NIPS) Agro Aversano-Litorale Domizio in Campania (southern Italy) within the framework of the project ECOREMED (LIFE11 ENV/IT/275) are used as a basis for reporting the main threats to soil fertility. In this paper we focus on soil degradation and contamination due to illegal waste disposal and burning, widespread phenomena in the NIPS in question, evaluating different options for soil remediation with agriculturebased techniques in light of their impact on the ecosystem services of soils. Bioremediation and assisted phytoremediation are recognized as the best options for protecting human health and enhancing environmental quality, maintaining agricultural soil functions with the application of relatively low-cost protocols. The purpose of agriculture-based remediation techniques is threefold: i) make the area in question safe, interrupting exposure to contaminant pathways through ecological structures such as dense reed plantations or dense turfgrass combined with high-density tree rows for reducing ground wind speed; ii) remediation, aiming to reduce the bioavailable fraction of potentially toxic elements (PTEs); iii) environmental restoration, to improve environment and landscape quality of degraded, but not contaminated land. The technical steps for carrying out phytoremediation projects and the results of their application are described for the following case studies monitored in Campania: i) agricultural soil contaminated by bioavailable Cd (San Giuseppiello site in Giugliano); ii) industrial soil heavily contaminated by Pb and Cd (Ecobat site in Marcianise); iii) agricultural soils potentially contaminated by non-bioavailable PTEs and organic pollutants (Giugliano and Trentola-Ducenta sites); iv) physically degraded soil (Teverola site). In all the case studies phytoremediation proved a low-cost tool to reduce risks for human health and enhance environmental quality, whilst maintaining soil fertility and improving ecosystem services.

potentially toxic elements (PTEs) to assess the relationship between spontaneous vegetation and pollution levels, the potential risks for biological communities and ecosystems, and the potential of native plant species for phytoremediation. PTE concentrations had negative effects on plant biodiversity, as determined through changes in the Shannon index, Pielou evenness index and species richness. Poaceae and Asteraceae were moderately affected by soil contamination, while PTE levels had a negative effect on the other species groups. Cadmium had the greatest effect on plant species diversity, followed by zinc and then lead. The ecological risk index showed a mean value of 4924, corresponding to a very high risk in most plants. Target PTEs for phytoremediation were Cd (3813 on average) followed by Pb (937 on average) contributing to the ecological risk index, respectively from 42 to 81% and from 11 to 24%, in spite of the much higher concentrations of Pb. The most frequent species were Holcus lanatus subsp. lanatus and Silene latifolia that showed good adaptability to contamination, growing in very high-risk areas. S. latifolia reported high concentrations of Tl both in shoot and in roots, at levels typical of hyperaccumulator species. High values of bioaccumulation (BACS, BACR) and translocation factors (TF) confirmed that this species may be considered a hyperaccumulator of Tl. Holcus lanatus and Silene latifolia proved the most suitable species respectively for Cd and Pb phytostabilization and can be used in association for soil cover during the summer when soil resuspension is generally more intense and for protecting groundwater from pollutant leaching.