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Common patterns of functional and biotic indices in response to multiple stressors in marine harbours ecosystems
2020
D’Alessandro, Michela | Porporato, Erika M.D. | Esposito, Valentina | Giacobbe, Salvatore | Deidun, Alain | Nasi, Federica | Ferrante, Larissa | Auriemma, Rocco | Berto, Daniela | Renzi, Monia | Scotti, Gianfranco | Consoli, Pierpaolo | Del Negro, Paola | Andaloro, Franco | Romeo, Teresa
Evaluating the effects of anthropogenic pressure on the marine environment is one of the focal objectives in identifying strategies for its use, conservation and restoration. In this paper, we assessed the effects of chemical pollutants, grain size and plastic litter on functional traits, biodiversity and biotic indices. The study was conducted on the benthic communities of three harbours in the central Mediterranean Sea: Malta, Augusta and Syracuse, subjected to different levels of anthropogenic stress (high, medium and low, respectively). Six traits were considered, subdivided into 22 categories: reproductive frequency, environmental position, mobility, life habit, feeding habit and bioturbation. Functional diversity indices analysed were: Functional Divergence, Quadratic Entropy, Functional Evenness and Functional Richness. To assess the trait responses to environmental gradients, we applied RLQ analysis, which considers simultaneously the relationship between three components: environmental data (R), species abundances (L) and species traits (Q). From our analyses, significant relationships (P-value = 0.0018 for permutation of samples, and P-value = 0.00027 for permutation of species) between functional traits and environmental data were highlighted. The trait categories significantly influenced by environmental variables were those representing feeding habits and mobility. In particular, the first category was influenced by chemical pollutants (organotin compounds and polycyclic aromatic hydrocarbons) and grain size (silt and sand), while the latter category was influenced only by chemical pollutants.Pearson correlations performed for functional vs biotic and diversity indices confirmed the validity of the chosen conceptual framework for harbour environments. Finally, linear models assessing the influence of stressors on functional parameters underlined the link between environmental data vs benthic and functional indices. Our results highlight the fact that functional trait analysis provides a useful and fast method for detecting in greater depth the effects of multiple stressors on functional diversity in marine ecosystems.
显示更多 [+] 显示较少 [-]Contamination of water resources of a small island state by fireworks-derived perchlorate: A case study from Malta
2019
Pace, Colette | Vella, Alfred J.
We have previously reported on the ubiquitous presence of perchlorate in the deposited and airborne fine dusts of Malta and shown that the source of the chemical in the dusts of this small central Mediterranean island is fireworks. There are no local geologic or anthropogenic sources of perchlorate other than firework manufacture and display. The hypothesis was tested that ground-deposited perchlorate will be mobilized in runoff and would partly migrate to the water table and eventually also affect tap water, one third of which being derived from groundwater. Forty four percent of 36 groundwater samples contained perchlorate above detection limit with mean and median values of 1.09 and 1.1 μg L−1. Sixty-two percent of 16 runoff samples collected during storms contained perchlorate above detection limit with mean and maximum concentrations, respectively, of 50.8 and 129 μg L−1, values which are far too high to be explained by atmospheric inputs given that rainwater perchlorate levels are typically <3 μg L−1. Between 42 and 89% of the tap waters analyzed in three sampling campaigns contained perchlorate above detection limit and had mean concentrations ranging from 0.4 to 1.6 μg L−1 suggesting contamination levels similar to those reported from China but lower than levels reported from the USA. The phenomenon of contamination of the water resources of Malta by perchlorate is probably unique in that it results not from geologic or industrial inputs but from an intense and prolonged pyrotechnic activity that is deeply rooted in the popular culture of the islanders.
显示更多 [+] 显示较少 [-]Identifying hotspots of non-indigenous species' high impact in the Maltese islands (Central Mediterranean Sea)
2021
Bartolo, Angela G. | Tsiamis, Konstantinos | Küpper, Frithjof C.
Several invasive non-indigenous species (NIS) cause ecological and socio-economic impacts. A good understanding of the impacts of invasive NIS in Mediterranean habitats is important for managing and prioritising measures in the marine environment. We applied a conservative additive model to sum up the Cumulative IMPacts of invasive Alien (CIMPAL) species of 19 invasive marine NIS on 13 habitats in Maltese waters. This analysis identified three hotspot areas of NIS' high impact and five top-priority together with four high-priority invasive NIS for management. By using CIMPAL, it was also possible to differentiate between areas within the same Marine Protected Area. CIMPAL is thus recommended as a good tool for managers and policy makers for prioritising measures as well as funds. Finally, recommendations are made with respect to future steps that are needed for the CIMPAL applicability, aiming to a more appropriate decision-making on prioritisation of hotspot areas and invasive marine NIS.
显示更多 [+] 显示较少 [-]Are Mediterranean Marine Protected Areas sheltered from plastic pollution?
2019
Liubartseva, S. | Coppini, G. | Lecci, R.
Comparisons of six selected Mediterranean MPAs were conducted to find similarities and site-specific differences in coastline fluxes and sources of plastic marine litter. Output from the recently developed 2D Lagrangian model for the Mediterranean was post-processed to study (1) the National Park of ses Salines d’Eivissa i Formentera, (2) Nature Reserve of Bouches de Bonifacio, (3) North-East Malta MPA, (4) Specially Protected Area of Porto Cesareo, (5) Community Importance Site of Torre Guaceto, and (6) Ethniko Thalassio Parko Alonnisou Voreion Sporadon. Model coastline fluxes of plastic ranged from 0.4 to3.6 kg (km day)−1, which is relatively low compared to the average flux of 6.2 ± 0.8 kg (km day)−1 calculated over the Mediterranean 2013–2017. Shipping was identified as a major source of plastic litter in all MPAs studied, contributing 55%–88% of total plastic. Site-specific rankings of the top 5 land-based plastic sources revealed that sea surface kinematics control plastic drift.
显示更多 [+] 显示较少 [-]Trace metals in harbour and slipway sediments from the island of Malta, central Mediterranean
2011
Huntingford, Emily J. | Turner, Andrew
Sediment samples collected from large harbours and public slipways on the island of Malta have been analysed for geochemically important metals (Al, Ca, Fe, Mn) and contaminant metals (As, Cd, Co, Cr, Cu, Ni, Pb, Sn, Zn) following fractionation (<63μm) and digestion in aqua regia. Absolute and Al-normalised concentrations of contaminant metals exhibited relatively little dispersion both among different samples from the same location and between samples from different locations, notable exceptions including lower concentrations of Cr and Sn on the slipways than in the harbours. Sources of contaminant metals are attributed to diffuse and specific waste inputs from urban surroundings and boating and shipping activities. Overall, concentrations are similar to those reported for other large harbours in urban settings where equivalent sample fractionation-digestion has been performed. Relative to various sediment quality guidelines, Pb is predicted to exert the greatest threat to the marine environment of Malta.
显示更多 [+] 显示较少 [-]Extended study on floating litter in Malta's coastal waters (Central Mediterranean)
2021
Curmi, Marta | Axiak, V. (Victor)
This study aims to determine the level of floating marine litter in coastal and inshore areas around Malta and Gozo (Central Mediterranean) and to investigate factors which influence litter distribution. Observations of macro-litter and mega-litter were conducted through seasonal boat surveys around Malta and Gozo during 2018–2019. Visual observations were conducted along line transects whilst maintaining a 6 m observation width. For coastal areas, of up to −1 km away from the shoreline, the total density of litter ranged between 27 and 2428 items/km², with a mean of 292 ± 85 items/km². Within inshore areas the density varied between 180 and 46,289 items/km², with a mean of 3242 ± 1880 items/km². The highest density was present in winter, this being 2.5 higher than the lowest density season. 91% of the litter was plastic. The manner in which anthropogenic factors and natural events influenced litter accumulations and distributions, are described.
显示更多 [+] 显示较少 [-]Current air quality plans in Europe designed to support air quality management policies
2015
Miranda, Ana | Silveira, Carlos | Ferreira, Joana | Monteiro, Alexandra | Lopes, Diogo | Relvas, Helder | Borrego, C. | Roebeling, Peter
The intensification of the human activity in urban areas as a result of the increasing population has contributed to the air pollution worsening in cities. To reverse this trend, the European Commission established a legal framework to improve the air quality. Thereby the Member States need to develop air quality plans (AQP) for zones and agglomerations where air quality limit values are exceeded, in order to implement pollution control strategies and meet the legal requirements. Understanding the reasons for the levels of air quality non–compliance as well as evaluating available and commonly used tools to predict the air quality and their effects, is crucial for the decision–making process on air quality management policies. Based on a compilation of regional and local AQP, a review of assessment capabilities and used modeling tools to evaluate the effects of emission abatement measures on the air quality and health was performed. In most cases, models are applied to estimate emissions and to assess the resulting air quality from both reference and emission abatement scenarios. Air quality’s impacts on the health and environment are rarely quantified. Regarding the air quality assessment, beyond the modeling, monitored data for validation of simulations are also used. Some studies, however, do not include the use of air quality models, considering the monitoring network as spatially representative of the study domain (e.g. Lisbon Region, Riga, Malta). In order to overcome methodological limitations for quantifying the impacts of emission abatement measures, economic evaluation techniques or even Integrated Assessment Methodologies (IAM) have been developed. IAM, already applied in some AQP or case studies, namely for Antwerp and London, are used for assessing how reductions in emissions contribute to improve air quality, reduce exposure and protect human health.
显示更多 [+] 显示较少 [-]Multitechnique diagnostic analysis and 3D surveying prior to the restoration of St. Michael defeating Evil painting by Mattia Preti
2022
D’Amico, Sebastiano | Comite, Valeria | Paladini, Giuseppe | Ricca, Michela | Colica, Emanuele | Galone, Luciano | Guido, Sante | Mantella, Giuseppe | Crupi, Vincenza | Majolino, Domenico | Fermo, Paola | La Russa, Mauro Francesco | Randazzo, Luciana | Venuti, Valentina
In this study, a multimethodological analysis involving optical and physical/chemical diagnostic techniques and 3D photogrammetric survey was successfully applied, for the first time, on the large oil on canvas St. Michael defeating Evil painting by Mattia Preti, located inside the Church of the Immaculate Conception of Sarria (Floriana) in Malta. Pigmenting agents, binder media, and raw materials were first characterized, both at elemental and molecular scales, through X-ray fluorescence spectroscopy (XRF), optical stereo microscopy (SM), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX), Fourier transform infrared spectroscopy (FT-IR), and gas chromatography coupled with mass spectrometry (GC-MS). The main goal was to properly identify the execution technique of this famous painter, the artist’s palette, and possible nondocumented interventions. The 3D photogrammetric survey, on the other side, allowed us to noninvasively evaluate the extension of the areas that experienced restorations, and to properly map the domains of the different canvasses observed. The joints between canvasses suggested that the painting was folded and rolled up. In addition, the employment of a thermal camera gave evidence of the different consolidating material injection points used during the restoration to strengthen the painting. The obtained results offer useful information for the development of optimized restoration and conservation strategies to be applied and provide, at the same time, answers to open questions related to provenance and dating of the investigated artwork.
显示更多 [+] 显示较少 [-]Investigating the dynamic eco-efficiency in agriculture sector of the European Union countries
2021
Pishgar-Komleh, Seyyed Hassan | Čechura, Lukáš | Kuzmenko, Elena
One of the main aims of European Common Agricultural Policy (CAP) has been established on a considerable reduction of greenhouse gas (GHG) emissions without any decline in productivity by 2030. This introduces some challenges in the assessment of agricultural technical efficiency. In particular, we can formulate at least two problems that are worth to be addressed: (i) possibility of treating undesirable outputs and (ii) panel data analysis of agricultural technical efficiency enriched by eco-efficiency assessment. In this study, we applied a Window Slack-Based Measurement Data Envelopment Analysis (W-SBM-DEA) model in the presence of undesirable outputs to evaluate the performance of agriculture sector of EU-27 countries during the period from 2008 to 2017. The country-level cultivated agricultural area, labor, specific costs, overheads, and depreciation were considered as the model inputs, and the gross value of country-level crop and livestock products represented the desirable outputs. The agricultural total GHG emissions at the country-level were accounted for as the undesirable output in the model. Having compared the results of different models, the substantial difference in the performance of the EU countries was registered mainly due to incorporating undesirable outputs and window analysis when using SBM-DEA model. The results of eco-efficiency assessment indicated that the Netherlands, Belgium, Italy, and Malta are the most eco-efficient countries with a score higher than 0.90, while the lowest eco-efficiency scores were reported for Slovakia, Latvia, and Estonia. The highest average eco-efficiency scores of all EU members were registered in 2011 (0.82), 2012 (0.83), and 2017 (0.84). A comparison of eco-efficiency performance between the old and new EU members indicated that the greater scores were obtained by old EU members. The variability assessment results showed a low variability and subsequently a high stability in the European agricultural sector, particularly in the Netherlands, Italy, and Malta. Based on our findings, it was concluded that for assessing agricultural technical efficiency in European agriculture in the context of eco-efficiency, application of a W-DEA model with undesirable output for a specified period of time reduces the impacts of temporary changes and provides more realistic results when comparing to models without undesirable output. These more realistic assessments of technical efficiency could help policy-makers to make more precise decisions.
显示更多 [+] 显示较少 [-]Estimating the role of climate changes on international tourist flows: evidence from Mediterranean Island States
2019
Katircioglu, Setareh | Cizreliogullari, Mehmet Necati | Katircioglu, Salih
This article examines the role of climate change on tourist flows to Malta, Cyprus (north), and Cyprus (south) which are major tourist destinations in the Mediterranean. Results from time series analyses reveal that climate change positively impacts on foreign tourist flows to these island states. Thus, this finding is reasonable where we argue that global warming leads to increases in international tourist arrivals to small island states. This paper has also found statistically significant effects of overall energy consumption on foreign tourist arrivals to Malta and Cyprus revealing that energy efficiency policies are essential in small island states.
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