Riuso dei sedimenti dragati nelle aree portuali: tecniche di trattamento, valutazione delle variazioni tessiturali, morfoscopiche e geochimiche ed ipotesi di intervento

SUMMARY Dredged sediments management requires a good knowledge of their textural, chemical and ecotoxicological features in order to select the best decontamination techniques allowing their reuse for environmental and civil interventions (Gardner et al., 2004; Michael et al., 2002; USACE / POAK, 1994; Burt and Murray, 2004) according to the national legislation (for instance in Italy the Legislative Decree no. 152/2006 and 1/2012). The study aims to analyze and discuss the modifications of the chemical and physical characteristics of the sediments dredged in the harbors of Ravenna, Livorno, Porto Garibaldi, Cervia, Cesenatico, Bellaria (Italy) and Midia (Romania) after decontaminations treatements. The results of the analysis have been then used to discuss the sediment reuse according to the national regulations. The sediments are generally constituted by fine or very fine sand and are characterized by a percentage of the fine fraction reaching 40 – 50% (silt and clay). Almost all the samples are contaminated by organic and inorganic pollutants with Lead, Vanadium, Mercury, Arsenic, IPA, C < = 12 and total hydrocarbons C> 12 that exceed the limits imposed by the Legislative Decree n. 152/2006. Only the sediments sampled in the harbor of Cervia and Bellaria did not present contamination. To obtain adequate quality standards (as defined by ICRAM - APAT, 2007), the contaminated sediments were treated with different experimental techniques (soil washing, sorting, landfarming, attrition and fusion with plasma torch). The results were used to quantify the performance of the decontamination’s treatment by measuring the changes and modifications in the sediments’ compositions. From the comparisons of the sediments’ characteristics before and after treatments, it appears that: -- Sediments presenting the minor textural variations were only treated with sorting that allows the separation of the sand fraction from the clay. -- The abrasion process, performed with attrition cell, has only induced a slight increase of silt and clay clearly due to the abrasion of particles. -- Sediments treated with plasma torch present a mean grain size greater than the native sediments. -- The landfarmig treatment, only used for the fine fraction of the sediment (< 63 μm) has not induced significant textural variations. The results of the geochemical analysis show that the sediments treated with soil washing, sorting and landfarming were totally or partially decontaminated, presenting a reduction of organic contaminants (for instance, the landfarming induce reductions of organic contaminants from 44% to 70%) and heavy metals. A change in the content of heavy metals has been observed in the sandy sediment during the test of the abrasion treatment and therefore the treatment does not allow establishing a unique trend of decontamination. Furthermore, the experiment realized with the plasma torch has demonstrated the possibility to extract silicon from the sediments as Iron-Silicon components (the Iron derives from the ferrous minerals of the sand) .The analysis carried out by SEM/EDS also allowed to characterize the molten material and minerals crystallized. The morphological changes of the particles due to the decontamination treatments have been observed using the Microscope Morphologi G3 Malvern and the optical microscope. The results highlight that only the plasma torch causes a radical change of the particles morphology, while the other treatments alter the aspect ratio, circularity and intensity mean parameters but less the convexity parameter. The characterizations allowed to establish, the reuse of decontaminated sediments. To assess the possible reuses in coastal areas and hinterland, several compatibility analyses (Krumbein and James, 1965) and morphological particles comparisons were performed. The results obtained indicate that the treated sediments can be used for submerged nourishment and filling interventions of quarries in the Ravenna province. Considering the proposed interventions, the results show that the total amount of sediment reusable of Ravenna port is about 3,500,000 m3 (sand, silt/clay), from a total of about 10 million m3. Taking into account the sediments treated by fusion (classified as inert) used in the construction industry, it is possible to hypothesize a total reuse of sediment. The study also showed that the use and combination of different decontamination treatments and the development of accurate management plans allow the reuse of all fractions of the dredged sediments, even the highly contaminated fine fraction. Finally, it has been demonstrated that decontaminated sediments, morphologically suitable for environmental reuse, were obtained from the treatments of soil washing, sorting and attrition. The fusion with the plasma torch allow the extraction of silicon, which has economical returns and a reuse of the sediments in the civil-infrastructure as well

The Willingness to Pay for Beach Scenery and its Preservation in Italy

In order to understand the multiple values of landscape, this paper suggests an evaluative methodology that takes into account a quantitative approach, public opinion, and an economic estimation. This study analyzes the coastal scenery of 40 Italian beaches using a fuzzy logic and a Contingent Valuation (CV). Each site was classified into five categories: Class I beaches were littorals with high natural settings; Class II sites were natural and semiurban beaches having low influences by anthropic structures; Classes III, IV, and V had lower evaluations due to poor physical and human condition. A questionnaire survey analyzed beach users’ preferences, judgment, and Willingness to Pay (WTP). Results suggest that landscape judgment is directly correlated to scenery assessment; therefore, beaches of Class I and II were judged beautiful while beaches of Class IV and V had poor judgments. Similarly, the importance given to the landscape was highest in Class I and II than in the others. WTP for the conservation of the selected beaches was about €16 per season. Our findings suggest that people are disposed to pay more for a beach with the top-grade of scenery (Class I and II) and low grade of urbanization. Moreover, WTP would rise for females and for nonresident users with an academic degree, which appreciated the coastal landscape

Percezione dell\u2019offerta turistico-balneare in Italia: aspettative, soddisfazione e conoscenze degli aspetti fisico-gestionali delle spiagge

Nell’estate 2015 è stata eseguita un’indagine della percezione degli utenti delle spiagge italiane. L’indagine, svolta in 41 spiagge di 11 Regioni, ha comportato la raccolta di 5.168 questionari. Nello studio le spiagge sono state suddivise secondo alcune classificazioni proposte in letteratura (classificazione antropogenica, delle attività presenti, di forma, di grado di urbanizzazione, sedimentologica). La frequentazione maggiore è stata riscontrata in spiagge urbane, a carattere ricreativo, lineari e sabbiose, ma sono risultate significative anche le presenze nelle spiagge rurali, di villaggio e resort. Il turismo prevalente è di tipo familiare, abituale e che soggiorna nelle località per periodi lunghi. La maggioranza degli utenti non è residente nel comune in cui trascorre le vacanze, ma sceglie la località turistica per il mare, la spiaggia e per la sua vicinanza. Gli elementi che qualificano una spiaggia sono principalmente quattro: mare pulito, pulizia della spiaggia, buona qualità dei servizi e delle strutture balneari, panorama e paesaggio. Questi elementi, se correlati con la tipologia di spiaggia scelta dagli utenti, dimostrano che il mare pulito e la buona qualità dell’acqua si riscontrano in spiagge di villaggio, resort e pocket beach ricadenti fuori dai principali centri urbani costieri. Buona qualità della spiaggia, dei servizi e della sicurezza sono principalmente riscontrate in spiagge di villaggio e urbane, di forma lineare od a tratti lineari e a baia artificiale. Infine, il paesaggio migliore secondo gli utenti è quello che si gode in spiagge resort, a bassa densità di urbanizzazione (spiagge di villaggio e rurali). Inoltre dall’indagine emerge come non vi sia una conoscenza profonda della gestione delle spiagge e delle opere che si realizzano per la protezione degli arenili; ciò si riflette nella scarsa disponibilità a pagare del turista per preservare la spiaggia

Data for the analysis of willingness to pay for Italian beaches

The data presented herein relates to the article entitled \u201cWillingness to pay for management and preservation of natural, semi-urban and urban beaches in Italy\u201d [1]. Data of several Italian beaches are collected considering shape, anthropogenic characteristics, use, activity and urbanization levels. Descriptive statistics of beach characteristics and beach users are presented, on the basis of about 5,000 interviews

Coastal scenery evaluation and management

This book describes an easy to apply methodology to determine the Bscenery^ or Bscenic value^ of a coast. Scenery may be defined as Bthe appearance of an area^ (Council of Europe 2000; Rangel-Buitrago et al. 2013) and it is a very important component for beach tourism because it drives the economy of many coastal countries (Ergin et al. 2006

Linking scenery and users\u2019 perception analysis of Italian beaches (case studies in Veneto, Emilia-Romagna and Basilicata regions)

The main purpose of this paper is to provide a scenic assessment of Italian beaches considering both physical and social aspects useful for defining coastal management strategies. Scenic values were calculated for 25 sites along Italian coastline using of a Coastal Scenic Evaluation System (CSES), a fuzzy logic containing 26 physical/human factors. The sites were categorized into five classes from Class I (top grade scenery) to Class V (poor scenery). Furthermore, a survey through questionnaires on Users' Perception (UP) was performed to obtain social assessment of the beaches and to define the beachgoer's characteristics for each scenic class. Five parameters (beach cleanliness, sea-water, beach width, landscape and crowding) were also combined to obtain a scenic and social analysis of the beaches. Three beaches belonged to Class I, e.g. remote or resort areas with a low impact of human activities and high score of natural parameters. Two Class II beaches were located at remote or rural areas having sand beaches, turquoise water and vigorous vegetation together with a low impact of tourist developments. Classes III, IV and V presented a wide distribution and their lower scores were linked to a poor environmental setting. These beaches were generally located in urban localities. Three aspects that were considered by the beach's users as the most important were beach cleanliness, good sea water and high quality of the services. However, UP assessment showed negative judgments on sea-water and landscape especially for Class IV and V beaches. On the other hand, cleanliness, recreational activities and facilities were well-judged for the Class III, IV and V beaches mainly due to the presence of private beach establishments. Scenic and social analysis of the beaches indicated that beach width was the best parameter both for scenic and social assessment; while crowding factor was a contradictory parameter presenting opposite trends of CSES and UP. Beach cleanliness, sea-water and landscape were depended to scenic Class of the beaches, both for CSES and UP. The excellent scenic values were associated to the environmental settings whereas human parameters usually showed low scores especially for urban beaches due to marine litter and the presence of coastal defense structures like groins and breakwaters. Nevertheless, users frequented both beaches with high and low parameters, due to their habitually frequentation and proximity to the beach. Finally, the results indicate that management strategies are also needed to improve the scenic quality and users' judgement of some beach features

THE RELATIONSHIP BETWEEN BEACH GEOMORPHOLOGY AND SUSTAINABLE TOURISM IN SANDY BEACHES: A CASE STUDY OF ROSOLINA MARE LITTORAL (VENETO REGION)

Beach carrying capacity assessment can be used as useful tools for planning sustainable tourism destinations. Assuming that the establishment of a maximum number of people can help tourist management, this study used two carrying capacity methods to estimate the carrying capacity of Rosolina Mare (Veneto region). To this purpose, the study considered the geomorphological characteristics of the beaches, the users’ perception and the environmental and management factors of the littoral. Our results suggest that the physical carrying capacity can be defined using geomorphological analyses, while the effective carrying capacity can be evaluated using the users' perception analysis