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Recently, several hectares of abandoned chestnut forests (ACF) were recovered into chestnut stands for nut or timber production, however, the effects of such practice on soil mineral horizon properties are unknown. This work aimed to (1) identify the better chestnut forest management to maintain or to improve the soil properties during the ACF recovery, and (2) give an insight into the effect of unmanaged to managed forest conversion on soil properties, taking in consideration sweet chestnut (Castanea sativa Mill.) forest ecosystems. The investigation was conducted in an experimental chestnut (Castanea sativa Mill.) forest located in the northern part of the Apennine chain (Italy). We identified an ACF, a chestnut forest for wood production (WCF), and chestnut forests for nut production with a tree density of 98 and 120 plants ha&minus, 1 (NCFL and NCFH, respectively). WCF, NCFL and NCFH stands are the result of the ACF recovery carried out in 2004. After 15 years since the ACF recovery, generally, the effects on the main soil chemical properties were negligible. Some differences occurred for the water-soluble organic carbon (WSOC) and microbial biomass and its activity. NCFL showed the highest WSOC content in the uppermost soil horizon likely due to higher amount of roots which are source of labile organic compounds. The higher WSOC amount might explain the greatest amount of microbial biomass in the A horizon of NCFL. Furthermore, the microbial biomass harboring in the A horizon of NCFL has also shown both a better C use efficiency and a larger soil organic carbon immobilization in the microbial biomass itself. Our data would indicate that the ACF recovery into pure chestnut forests did not have negative impacts on soil chemical and biochemical properties, though chestnut stands for nut production with a low plant density are the most suitable ones.

This study has been aimed at evaluating by means of plant bioindicators pollution resulting from atmospheric deposition of potentially toxic elements (PTE) in the urban and suburban areas of Ravenna. Therefore, three different areas were taken into account: an area of natural interest, a public green area and a cultivated area, chosen for their particular locations relative to anthropogenic impact. The research has determined 22 macro- and micro-elements, both in the leaves of vascular plants and native mosses, and the isotopic compositions of strontium (Sr: 87Sr/86Sr) and neodymium (Nd: 143Nd/144Nd) in mosses. The chemical characterization of ever-green and deciduous trees over a year time and their temporal trends indicate a sea-sonal pattern which depends on the plant species and the element investigated, al-though accumulation of PTE has been especially observed in the fall. Unlike con-centrations measured in the leaves, mosses provide estimates of possible enrich-ment occurred over the years. For several metals, especially Cd, Cu, Sn and Zn, their enrichment factors in mosses show that the contamination threshold ranges from severe to extreme in several stations of the investigated areas. A correlation exists between the plants exposed to high vehicular traffic and the release of Pt, al-though the amount of Pt intercepted and retained by leaf blades results not to be absorbed, supporting the low bioavailability of this element. The use of mosses as bioindicators to define the natural and anthropogenic sources of the atmospheric particulate has shown that the joint application of Sr and Nd isotopes can provide important information on the air pollution processes.

Sixteen profiles have been characterized from a pedologic point of view: nine in a coastal pinewood, five in agricultural sites and two in a city park. The profiles have been described, sampled and analysed to the purpose of giving a first outline of the pedological complexity of area. Inside the pinewood, soils are affected by the topographical position and the closeness of the surface aquifer. Ustipsamments/ Arenosols occur where the groundwater depth is more than one meter, while at lower groundwater depth Psammaquents/Gleysols are present. Agricultural soils are directly affected by geological characteristics and human land reclamation, and fall within the Haplustepts/Cambisols great groups, with a few distinctions due to the different utilisation of the soil and to the depositional origin. Also the two soils of the city park fall in the Haplustepts/Cambisols great group; however, in this case, the anthropic interference, suggested by the plenty brick fragments detected in the profiles, is quite evident. .

Potentially toxic elements (PTEs) abundances in top soil and along the soil profiles from areas affected by different anthropogenic inputs were investigated. The study area is located within the Ravenna Municipality, a complex territorial system highly affected by industrial (a large petrolchemical complex) agricultural activi-ties. Three zones with distinct environmental features were identified: the San Vitale Pinewood affected by atmospheric deposition pollutans from the industrial complex (PW1, PW4, PW6 and PW8 soil profiles); a public garden within the Ra-venna city center, mainly affected by traffic pollution (GP1 soil profile); the "Luigi Perdisa" farm located immediately northwards Ravenna was selected due to the use of fertilizers as well as atmospheric deposition (PER2 soil profile). The total con-centration of PTEs (Ba, Cr, Cu, Cr, Ni, Pb, Zn) was determined by X ray fluores-cence spectrometry (XRF), and the pseudo-total concentration with aqua regia di-gestion (AR) and ICP-OES quantification in order to evaluate the extractability of the elements. Results showed a significant increase of some PTEs (Cu, Pb, Zn) in the top soil compared to the endopedon. In the Ravenna urban park (GP1 station), Pb and Zn concentrations exceeded the threshold values established by current Ital-ian laws for soils from "public, residential and private areas" (D. Lgs 152/2006). The correlation between top soil and the subsoil highlighted that some PTEs, such as Cu, Pb and Zn, are anthropogenic and they are mainly associated to the deposi-tion of airborne pollutants, whereas other elements (Cr and Ni) are lithogenic.

The hazard assessment of some potentially toxic chemicals assumes significance in view of Italian and Community legislation concerning the protection of human health, water and land pollution (use of compost in agriculture, spreading of sludge and water, relapse fine particles, etc.). This chapter explained the environmental role of several potentially toxic elements. In this regard, the knowledge of the speciation of elements in the environment is important to identify not only the absolute concentrations (mg / kg soil) but also the relationship of the element accumulation in plant tissues and the hazard in the food chain

Le aree marine costiere sono ambienti caratterizzati da un elevato valore naturalistico, economico e turistico. Tra di esse, le lagune sono caratterizzate da un elevato valore ecologico ma rappresentano anche aree particolarmente vulnerabili, dove l’accumulo di contaminanti nei sedimenti è diffuso e frequente. Precedenti ricerche sul mercurio (Hg) hanno evidenziato un elevato stato di contaminazione della Pialassa Baiona, presso Ravenna. Questo ambiente lagunare è stato interessato da un ingente apporto di Hg (≈100-200 tonn.), rilasciato da un impianto di produzione dell’acetaldeide nel periodo 1957-1977. In questo studio, la rimobilizzazione del Hg all’interfaccia acqua-sedimento è stata indagata per mezzo di una camera bentica in situ. Il flusso di Hg totale dal sedimento alla colonna d’acqua è risultato comparabile a quanto osservato in un ambiente simile contaminato da Hg, la Laguna di Grado (Nord Adriatico), sebbene il contenuto di Hg nei sedimenti di Grado sia inferiore di circa il 50% rispetto alla Pialassa. Viceversa, il flusso giornaliero (8 ore) per la forma metilata si è rivelato estremamente basso in Pialassa Baiona, pari al 7% di quanto osservato sperimentalmente in Laguna di Grado. A dispetto delle elevate concentrazioni di Hg nei sedimenti, le generali condizioni anossiche dei sedimenti in Pialassa Baiona sembrano limitare la mobilità e la biodisponibilità del metallo, mitigando gli effetti dell’accumulo di questo contaminante nell’ambiente lagunare.

This paper is focused on the multicomponent exchange processes and elemental cycling in the subsurface and superficial environments which constitute the area of the Pineta di San Vitale and nearby farmlands. The coastal aquifers in the area of the Pineta underwent severe seawater intrusion due to subsidence and over-pumping, yielding a decline in the water quality and driving a number of processes in aquifers and soils. These include cation-exchange reactions by clay minerals, even if the cation exchange capacity of the aquifer is probably low; iron oxy-hydroxides extensive precipitation due to oxic seawater recirculation; adsorption processes of both essential micronutrient and potentially toxic elements on the sur-face of Fe and Al hydroxides. The development of local anoxic conditions due to respiration and decomposition of organic matter allows the reductive dissolution of the iron oxy-hydroxides, which liberate the sorbed elements to porewaters. This re-dox cycling appears to be important in the bioavailability and geochemical cycling of a number of trace metals in the subterranean environment of the Pineta. CO2 charged waters in soils account for the high alkalinity observed in most water sam-ples, through the role of carbonates and the control of pH and the Ca2+ content. The active processes in the surface ecosystem of the plain bordering the Pineta di San Vitale, exploited for agricultural uses, include dry and wet atmospheric deposi-tion from marine and anthropogenic sources, leaching processes during runoff and retention and transport of trace elements by Fe and Mn oxides colloidal particles, through the network of canals and ditches towards the coastland. These processes are sensitive to flow fluctuations, and are deeply influenced by the management of water resources during summer, when a high water supply in irrigated crops is re-quired. Using geochemical simulation codes it is highlighted that the reverse phe-nomenon to salinization, leading to groundwater freshening, is a long process, also depending on the low cation exchange capacity of the site. Even if a detailed study concerning the recharge rate of the aquifers would be necessary, these preliminary observation indicate that attenuation planning for salinization is urgent.

Scopo della ricerca è stato quello di verificare il contenuto naturale e la presenza di arricchimenti superficiali, di alcuni PTE in suoli del Comune di Ravenna (Italia). Sono stati campionati 48 siti e prelevati campioni di suolo alla profondità di 0-30 cm e 80-100 cm, andando a quantificare le aliquote totali ed assimilabili di Ag, Cd, Ni e Pb mediante ICP-OES, ed i contenuti totali di Ni e Pb mediante XRF. La dotazione naturale risulta in linea con i valori di suoli non contaminati. In alcuni siti i valori superficiali di Ag, Ni, Cd e Pb superano i contenuti naturali dell’area. Le aliquote assimilabili sono sempre superiori in superficie che in profondità. Gli indici geochimici sottolineano la duplice provenienza dei sedimenti dell’area esaminata. Lo studio ha evidenziato arricchimenti superficiali per il Cd, nessuno per il Ni. L’analisi statistica ha evidenziato come le misurazioni effettuate con ICP-OES ed XRF restituiscono valori significativamente differenti.

A public property site, situated over an alluvial terrace of the Idice Stream (Emilia Romagna Region-Italy) has been contaminated by a layer of waste, constituted by vitrified fly ashes and ceramic materials produced by an incinerator of municipal solid waste. The waste have high contents of heavy metals and exceed the Italian Law Limits of concentration for Cd, Cu, Pb and Zn (D. Lgs. 152/06, all. 5, tab.1). The in-situ remediation of the area was possible. In this study, alternative materials than the Portland cement has been tested for the environmental restoration and the further naturalization of the area. Leaching tests has been carried out treating the ashes with different concentrations of hydrated lime (CaOH2) and also with lime at 20% concentration and smectitic marlstone. At the end of the leaching test, most of the heavy metals in the waste has been immobilized by the lime/marlstone treatment.

Trace elements and O-H-Sr-B isotopic data have been obtained on superficial waters from a number of canals and ditches which serves the water demand for irrigation in the Ravenna coastal plain, in order to highlight the cycling of potentially toxic elements and the role of different sources to the solute. Two different surveys were conducted during March and July 2008, intended as representative of the water faces during winter and summer, respectively. In summer, the water mass balance in the network is mostly controlled by the ingression of freshwaters from the Canale Emiliano Romagnolo (CER). The O-H isotopic data indicate that, during winter, waters are primarily recharged from Apennine catchments and undergo evaporation at different extents. The boron isotopic signature indicates the important role played by the marine component. A major seawater contribution is evidenced in canals sampled in proximity to the coastline; however, the process controlling the origin of dissolved boron is not solely related to direct mixing with sea water but requires an additional source probably related to water-soil exchanges, leaching boron of marine origin due to the prolonged exposure to sea water of alluvial sediments. An additional boron contribution from the agricultural practice is also evidenced. Calculation based on the conservative behaviour of chloride indicates that in canals and ditches not directly connected with the sea up to the 80% of the Sr budget did not originated from seawater, indicating a source from Al-silicates mineral and supporting the hypothesis of significant soil-water interactions and chemical exchanges. The positive correlation between pH and dissolved oxygen in winter waters is likely to reflect CO2 consumption during algal photosynthesis, favoring the in-situ generation of colloidal particles due to the oxidative precipitation of ferric iron oxy-hydroxides and probably small carbonate particles, which are able to adsorb trace metals on the surface and contribute to the ecosystem dynamics facilitating the transport of metals and affecting their bio-availability and cycling. During summer, the input of freshwater from CER lowers the concentration of most ions and superimposes to the evaporation-precipitation-exchange cycle, possibly dispersing the colloidal particles which could act as pollutant carriers and enhancing flocculation and precipitation, scavenging trace metals into the sediments.

Within the PRIN 2007-2009 project, "Geochemical balance for the assessment of the agro-environmental quality in a complex territorial system: the case of Ravenna", thirteen profiles have been characterized from a pedologic point of view: nine in a coast pinewood, two in a farm and two in a city park. The profiles have been described, sampled and analysed to the purpose of giving a first outline of the pedologic complexity of areas under examination. Inside the pinewood, soils are remarkably affected by the topographic position and the closeness of the surface aquifer. Typic Ustipsamments correspond to elevated aquifer depths, Typic Psammaquents correspond to limited depths and Aquic Ustipsamments, to intermediate ones. The two farm soils fall within the Udifluventic Haplustepts, with a few distinctions determined by a different utilisation of the soil and by the depositional origin. Also the two soils in the city park fall in the Udifluventic Haplustepts; however, in this case the anthropic interference suggested by the plenty brick fragments detected in the profiles is quite evident. Keyword: soils classification; soil chemistry

Résumé Il n'y a pas longtemps, le développement socio-économique des lieux était conditionné uniquement par la disponibilité (ou non) d'eau. Pendant ces dernières années, le problème de la pollution des eaux, causé par les quantités considérables de produits toxiques reversés dans les cours d'eaux, a presque dépassé par son importance le problème de la quantité d'eau. Intervenir pour résoudre ce problème est désormais une obligation pour la majorité des pays à haute densité de population et à fort développement industriel. La résolution du problème impose qu’à côté des technologies et des études qui visent à l'assainissement des cours d'eaux dégradés, soient développées des normes et des réglementations législatives pour sauvegarder la ressource d'eau. Ici, on reparcourt l'iter législatif en matière de qualité des eaux qui, commencé en Italie à partir du Décret Legislatif 152/2006, représente aujourd'hui le Texte Unique en matière d'environnement. En s'inspirant du même décret, on fait une comparaison entre les normes à propos de la réutilisation des eaux usées, et les normes proposées par la communauté EU et par l'Environmental Protection Agency (EPA) des Etats Unis, qui en 1992 a publié le « Guidelines for Water Reuse ». Les contenus de cet écrit sont considérés novateurs par rapport aux précédents documents sur le thème, puisqu'ils sont destinés à diffuser le concept de la réutilisation de l’eau en dehors du secteur agricole. Mots-clés: legislation, ressource en eau, eaux usées, épuration, qualité des eaux

Una serie di controlli stratigrafici operati nel 2005 su invito della Soprintendenza Archeologica dell'Emilia-Romagna in cantieri della città di Bologna ha condotto all'individuazione di suoli sepolti a varia profondità. La presenza di materiali archeologici nelle sequenze stratigrafiche ha permesso considerazioni sulla relazione tra tempo e tipo pedologico sviluppato e tra tipo di suolo e geomorfologia. In particolare, in due siti ubicati in aree marginali al piccolo conoide su cui sorge la città sono stati studiati un suolo vertico dell'Olocene antico ed un probabile inceptisuolo evolutosi fino ad età romana inoltrata su una coltre sedimentaria della prima età del Ferro. La radiodatazione della materia organica contenuta nei suoli ha fornito per il primo l'età calibrata (1 sigma) di 9.300-8.650 anni BP e per il secondo 3.150-2.840 BP. Il suolo vertico non è coevo al deterioramento climatico dell'Optimum Climatico olocenico del 8.200 BP, anticipandolo di circa 800 anni. Il confronto con altri vertisuoli sepolti regionali sottolinea per tale ordine di suoli l'importanza del contrasto stagionale nuovamente ricomparso dopo il termine dell'ultimo periodo glaciale. Il forte movimento del CaCO3 , testimoniato dalla presenza di un orizzonte Bkb ben sviluppato è legato al chimismo delle acque di falda provenienti dal bacino montano marnoso del torrente Aposa. La distribuzione fisiografica dei suoli vertici sotto la città di Bologna si mostra probabilmente in relazione con il margine del conoide inteso come limite dinamico tra ambiti deposizionali di corsi d'acqua adiacenti. In queste aree, locali contropendenze devono aver indotto condizioni di ristagno idrico superficiale stagionale in grado di mantenersi attraverso il tempo e/o riproporsi più volte. Il significato di tali suoli è quindi principalmente stazionale e non strettamente paleoclimatico. Il suolo "romano" (punto 2) evolve per circa 1.000-1.200 anni; mentre non si è ancora in grado di definire il reale arco cronologico d'evoluzione del vertisuolo più antico.

Il presente studio è incentrato sulla caratterizzazione quali-quantitativa della sostanza organica umificata estratta e purificata dagli orizzonti organo-minerali A1 e A2 di quattro suoli forestali, appartenenti alle terre brune acide dell'Appennino Emiliano. I profili scelti per lo studio si sono formati ed evoluti su di un substrato litologico di arenarie quarzoso-feldspatiche (Formazione di Monghidoro) e rientrano, dal punto di vista evolutivo, negli ordini degli Entisols (Mong 30-31 e 34) e degli Inceptisols (Mong 33). Si sono scelte due tipologie di coperture arboree, al fine di individuare differenze nelle caratteristiche della frazione organica umificata, riconducibili alla natura di diversi apporti vegetali. Per osservare come la copertura vegetale influisca sulla frazione organica umificata i campioni sono stati prelevati sotto bosco puro di faggio (Fagus sylvatica L.) e sotto copertura mista o con prevalenza di conifere (Pseudotsuga menziesii Franco ed Abies alba M.). Le analisi effettuate sono state la determinazione del C organico nelle varie forme: totale (Corg), estraibile (Cestr), umificato (CHA e CFA), dei parametri di umificazione (HU%, HR%, HI) e la componente organica estratta, purificata e liofilizzata, è stata analizzata mediante titolazione potenziometrica, analisi termica (TG-DSC) ed analisi spettroscopica infrarossa in trasformata di Fourier (FT-IR). Ciò che è emerso dall'analisi dei risultati è sicuramente la maggior dotazione di C organico totale e la miglior qualità del C organico umificato dei suoli posti sotto copertura di latifoglie e la maggior dotazione di gruppi funzionali acidi di tipo carbossilico (COOH) della frazione a basso peso molecolare della sostanza organica umificata (FA) sotto entrambi i tipi di copertura. Dalle determinazioni termiche e spettroscopiche in generale, è emersa l'influenza della diversa copertura arborea sulla frazione umica ma non su quella fulvica della sostanza organica.