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High resolution estimates of the corrosion risk for cultural heritage in Italy
2017
De Marco, Alessandra | Screpanti, Augusto | Mircea, Mihaela | Piersanti, Antonio | Proietti, Chiara | Fornasier, M Francesca
Air pollution plays a pivotal role in the deterioration of many materials used in buildings and cultural monuments causing an inestimable damage. This study aims to estimate the impacts of air pollution (SO2, HNO3, O3, PM10) and meteorological conditions (temperature, precipitation, relative humidity) on limestone, copper and bronze based on high resolution air quality data-base produced with AMS-MINNI modelling system over the Italian territory over the time period 2003–2010. A comparison between high resolution data (AMS-MINNI grid, 4 × 4 km) and low resolution data (EMEP grid, 50 × 50 km) has been performed. Our results pointed out that the corrosion levels for limestone, copper and bronze are decreased in Italy from 2003 to 2010 in relation to decrease of pollutant concentrations. However, some problem related to air pollution persists especially in Northern and Southern Italy. In particular, PM10 and HNO3 are considered the main responsible for limestone corrosion. Moreover, the high resolution data (AMS-MINNI) allowed the identification of risk areas that are not visible with the low resolution data (EMEP modelling system) in all considered years and, especially, in the limestone case. Consequently, high resolution air quality simulations are suitable to provide concrete benefits in providing information for national effective policy against corrosion risk for cultural heritage, also in the context of climate changes that are affecting strongly Mediterranean basin.
Show more [+] Less [-]The well sorted fine sand community from the western Mediterranean Sea: A resistant and resilient marine habitat under diverse human pressures
2017
Dauvin, Jean-Claude | Bakalem, Ali | Baffreau, Alexandrine | Delecrin, Claire | Bellan, Gérard | Lardicci, Claudio | Balestri, Elena | Sardá, Rafael | Grimes, Samir
The Biocoenosis of Well Sorted Fine Sands (WSFS) (SFBC, Sables Fins Bien Calibrés in French) is a Mediterranean community very well delimited by bathymetry (2–25 m) and sedimentology (>90% of fine sand) occurring in zones with relatively strong hydrodynamics. In this study focused on sites located along the Algerian, French, Italian and Spanish coasts of the Western Basin of the Mediterranean Sea (WBMS) we aim to compare the structure, ecological status and diversity of the macrofauna of the WSFS and examine the effects of recent human pressures on the state of this shallow macrobenthic community. We assess the ecological status and functioning of these WSFS using three categories of benthic indices: a) five indices based on classification of species into ecological groups, AMBI, BO2A, BPOFA, IQ and IP, b) the ITI index based on classification of species in trophic groups, and c) the Shannon H’ index, and the Biological Traits Analysis (BTA), which is an alternative method to relative taxon composition analysis and integrative indices. Cluster analyses show that each zone show a particular taxonomic richness and dominant species. The seven benthic indices reveal that the macrobenthos of the WSFS of the four coastal zones show good or high Quality Status, except for one location on the Algerian coast (the Djendjen site) in 1997. BTA highlights the presence of three groups of species: 1) typical characteristic species; 2) indicator species of enrichment of fine particles and organic matter, and 3) coarse sand species which are accessorily found on fine sand. Finally, the WSFS which are naturally subject to regular natural physical perturbations show a high resilience after human pressures but are very sensitive to changes in the input of organic matter.
Show more [+] Less [-]Spatial variation of atmospheric nitrogen deposition and critical loads for aquatic ecosystems in the Greater Yellowstone Area
2017
Nanus, L. | McMurray, J.A. | Clow, D.W. | Saros, J.E. | Blett, T. | Gurdak, J.J.
Current and historic atmospheric nitrogen (N) deposition has impacted aquatic ecosystems in the Greater Yellowstone Area (GYA). Understanding the spatial variation in total atmospheric deposition (wet + dry) of N is needed to estimate air pollution deposition critical loads for sensitive aquatic ecosystems. This is particularly important for areas that have an increasing contribution of ammonia dry deposition to total N (TN), such as the GYA. High resolution geostatistical models and maps of TN deposition (wet + dry) were developed using a variety of techniques including ordinary kriging in a geographic information system, to evaluate spatial variability and identify areas of elevated loading of pollutants for the GYA. TN deposition estimates in the GYA range from <1.4 to 7.5 kg N ha−1 yr−1 and show greater variability than wet inorganic N deposition. Critical loads of TN deposition (CLTNdep) for nutrient enrichment in aquatic ecosystems range from less than 1.5 ± 1.0 kg N ha−1 yr−1 to over 4.0 ± 1.0 kg N ha−1 yr−1 and variability is controlled by differences in basin characteristics. The lowest CLTNdep estimates occurred in high elevation basins within GYA Wilderness boundaries. TN deposition maps were used to identify critical load exceedances for aquatic ecosystems. Estimated CLTNdep exceedances for the GYA range from 17% to 48% depending on the surface water nitrate (NO3−) threshold. Based on a NO3− threshold of 1.0 μmol L−1, TN deposition exceeds CLTNdep in approximately 30% of the GYA. These predictive models and maps can be used to help identify and protect sensitive ecosystems that may be impacted by excess atmospheric N deposition.
Show more [+] Less [-]Widespread legacy brine contamination from oil production reduces survival of chorus frog larvae
2017
Hossack, Blake R. | Puglis, Holly J. | Battaglin, William A. | Anderson, Chauncey W. | Honeycutt, R Ken | Smalling, Kelly L.
Advances in drilling techniques have facilitated a rapid increase in hydrocarbon extraction from energy shales, including the Williston Basin in central North America. This area overlaps with the Prairie Pothole Region, a region densely populated with wetlands that provide numerous ecosystem services. Historical (legacy) disposal practices often released saline co-produced waters (brines) with high chloride concentrations, affecting wetland water quality directly or persisting in sediments. Despite the potential threat of brine contamination to aquatic habitats, there has been little research into its ecological effects. We capitalized on a gradient of legacy brine-contaminated wetlands in northeast Montana to conduct laboratory experiments to assess variation in survival of larval Boreal Chorus Frogs (Pseudacris maculata) reared on sediments from 3 local wetlands and a control source. To help provide environmental context for the experiment, we also measured chloride concentrations in 6 brine-contaminated wetlands in our study area, including the 2 contaminated sites used for sediment exposures. Survival of frog larvae during 46- and 55-day experiments differed by up to 88% among sediment sources (Site Model) and was negatively correlated with potential chloride exposure (Chloride Model). Five of the 6 contaminated wetlands exceeded the U.S. EPA acute benchmark for chloride in freshwater (860 mg/L) and all exceeded the chronic benchmark (230 mg/L). However, the Wetland Site model explained more variation in survival than the Chloride Model, suggesting that chloride concentration alone does not fully reflect the threat of contamination to aquatic species. Because the profiles of brine-contaminated sediments are complex, further surveys and experiments are needed across a broad range of conditions, especially where restoration or remediation actions have reduced brine-contamination. Information provided by this study can help quantify potential ecological threats and help land managers prioritize conservation strategies as part of responsible and sustainable energy development.
Show more [+] Less [-]Sources, distribution and export coefficient of phosphorus in lowland polders of Lake Taihu Basin, China
2017
Huang, Jiacong | Gao, Junfeng | Jiang, Yong | Yin, Hongbin | Amiri, Bahman Jabbarian
Identifying phosphorus (P) sources, distribution and export from lowland polders is important for P pollution management, however, is challenging due to the high complexity of hydrological and P transport processes in lowland areas. In this study, the spatial pattern and temporal dynamics of P export coefficient (PEC) from all the 2539 polders in Lake Taihu Basin, China were estimated using a coupled P model for describing P dynamics in a polder system. The estimated amount of P export from polders in Lake Taihu Basin during 2013 was 1916.2 t/yr, with a spatially-averaged PEC of 1.8 kg/ha/yr. PEC had peak values (more than 4.0 kg/ha/yr) in the polders near/within the large cities, and was high during the rice-cropping season. Sensitivity analysis based on the coupled P model revealed that the sensitive factors controlling the PEC varied spatially and changed through time. Precipitation and air temperature were the most sensitive factors controlling PEC. Culvert controlling and fertilization were sensitive factors controlling PEC during some periods. This study demonstrated an estimation of PEC from 2539 polders in Lake Taihu Basin, and an identification of sensitive environmental factors affecting PEC. The investigation of polder P export in a watershed scale is helpful for water managers to learn the distribution of P sources, to identify key P sources, and thus to achieve best management practice in controlling P export from lowland areas.
Show more [+] Less [-]The role of melting alpine glaciers in mercury export and transport: An intensive sampling campaign in the Qugaqie Basin, inland Tibetan Plateau
2017
Sun, Xuejun | Wang, Kang | Kang, Shichang | Guo, Junming | Zhang, Guoshuai | Huang, Jie | Cong, Zhiyuan | Sun, Shiwei | Zhang, Qianggong
Glaciers, particularly alpine glaciers, have been receding globally at an accelerated rate in recent decades. The glacial melt-induced release of pollutants (e.g., mercury) and its potential impact on the atmosphere and glacier-fed ecosystems has drawn increasing concerns. During 15th–20th August, 2011, an intensive sampling campaign was conducted in Qugaqie Basin (QB), a typical high mountain glacierized catchment in the inland Tibetan Plateau, to investigate the export and transport of mercury from glacier to runoff. The total mercury (THg) level in Zhadang (ZD) glacier ranged from <1 to 20.8 ng L−1, and was slightly higher than levels measured in glacier melt water and the glacier-fed river. Particulate Hg (PHg) was the predominant form of Hg in all sampled environmental matrices. Mercury concentration in Qugaqie River (QR) was characterized by a clear diurnal variation which is linked to glacier melt. The estimated annual Hg exports by ZD glacier, the upper river basin and the entire QB were 8.76, 7.3 and 157.85 g, respectively, with respective yields of 4.61, 0.99 and 2.74 μg m−2 yr−1. Unique landforms and significant gradients from the glacier terminus to QB estuary might promote weathering and erosion, thereby controlling the transport of total suspended particulates (TSP) and PHg. In comparison with other glacier-fed rivers, QB has a small Hg export yet remarkably high Hg yield, underlining the significant impact of melting alpine glaciers on regional Hg biogeochemical cycles. Such impacts are expected to be enhanced in high altitude regions under the changing climate.
Show more [+] Less [-]Loggerhead sea turtles (Caretta caretta): A target species for monitoring litter ingested by marine organisms in the Mediterranean Sea
2017
Matiddi, Marco | Hochsheid, Sandra | Camedda, Andrea | Baini, Matteo | Cocumelli, Cristiano | Serena, Fabrizio | Tomassetti, Paolo | Travaglini, Andrea | Marra, Stefano | Campani, Tommaso | Scholl, Francesco | Mancusi, Cecilia | Amato, Ezio | Briguglio, Paolo | Maffucci, Fulvio | Fossi, Maria Cristina | Bentivegna, Flegra | de Lucia, Giuseppe Andrea
Marine litter is any persistent, manufactured or processed solid material discarded, disposed of or abandoned in the marine and coastal environment. Ingestion of marine litter can have lethal and sub-lethal effects on wildlife that accidentally ingests it, and sea turtles are particularly susceptible to this threat. The European Commission drafted the 2008/56/EC Marine Strategy Framework Directive with the aim to achieve a Good Environmental Status (GES), and the loggerhead sea turtle (Caretta caretta, Linnaeus 1758) was selected for monitoring the amount and composition of litter ingested by marine animals. An analogous decision has been made under the UNEP/MAP Barcelona Convention for the protection of the Mediterranean Sea, following the Ecosystem Approach. This work provides for the first time, two possible scenarios for the Marine Strategy Framework Directive GES, both related to “Trends in the amount and composition of litter ingested by marine animals” in the Mediterranean Sea. The study validates the use of the loggerhead turtle as target indicator for monitoring the impact of litter on marine biota and calls for immediate use of this protocol throughout the Mediterranean basin and European Region. Both GES scenarios are relevant worldwide, where sea turtles and marine litter are present, for measuring the impact of ingested plastics and developing policy strategies to reduce it. In the period between 2011 and 2014, 150 loggerhead sea turtles, found dead, were collected from the Italian Coast, West Mediterranean Sea Sub-Region. The presence of marine litter was investigated using a standardized protocol for necropsies and lab analysis. The collected items were subdivided into 4 main categories, namely, IND-Industrial plastic, USE-User plastic, RUB-Non plastic rubbish, POL-Pollutants and 14 sub-categories, to detect local diversity. Eighty-five percent of the individuals considered (n = 120) were found to have ingested an average of 1.3 ± 0.2 g of litter (dry mass) or 16 ± 3 items.
Show more [+] Less [-]Microplastic contamination in Lake Winnipeg, Canada
2017
Anderson, Philip J. | Warrack, Sarah | Langen, Victoria | Challis, Jonathan K. | Hanson, Mark L. | Rennie, Michael D.
Microplastics are an emerging contaminant of concern in aquatic ecosystems. To better understand microplastic contamination in North American surface waters, we report for the first time densities of microplastics in Lake Winnipeg, the 11th largest freshwater body in the world. Samples taken 2014 to 2016 revealed similar or significantly greater microplastic densities in Lake Winnipeg compared with those reported in the Laurentian Great Lakes. Plastics in the lake were largely of secondary origin, overwhelmingly identified as fibres. We detected significantly greater densities of microplastics in the north basin compared to the south basin of the lake in 2014, but not in 2015 or 2016. Mean lake-wide densities across all years were comparable and not statistically different. Scanning electron microscopy with energy dispersive X-ray spectroscopy indicated that 23% of isolated particles on average were not plastic. While the ecological impact of microplastics on aquatic ecosystems is still largely unknown, our study contributes to the growing evidence that microplastic contamination is widespread even around sparsely-populated freshwater ecosystems, and provides a baseline for future study and risk assessments.
Show more [+] Less [-]Future heat waves due to climate change threaten the survival of Posidonia oceanica seedlings
2017
Guerrero-Meseguer, Laura | Marín, Arnaldo | Sanz-Lázaro, Carlos
Extreme weather events are major drivers of ecological change, and their occurrence is likely to increase due to climate change. The transient increases in atmospheric temperatures are leading to a greater occurrence of heat waves, extreme events that can produce a substantial warming of water, especially in enclosed basins such as the Mediterranean Sea. Here, we tested the effects of current and predicted heat waves on the early stages of development of the seagrass Posidonia oceanica. Temperatures above 27 °C limited the growth of the plant by inhibiting its photosynthetic system. It suffered a reduction in leaf growth and faster leaf senescence, and in some cases mortality. This study demonstrates that the greater frequency of heat waves, along with anticipated temperature rises in coming decades, are expected to negatively affect the germination of P. oceanica seedlings.
Show more [+] Less [-]Investigation of PM2.5 mass concentration over India using a regional climate model
2017
Bran, Sherin Hassan | Srivastava, Rohit
Seasonal variation of PM2.5 (Particulate Matter <2.5 μm) mass concentration simulated from WRF-Chem (Weather Research and Forecasting coupled with Chemistry) over Indian sub-continent are studied. The simulated PM2.5 are also compared with the observations during winter, pre-monsoon, monsoon and post-monsoon seasons of 2008. Higher value of simulated PM2.5 is observed during winter followed by post-monsoon, while lower values are found during monsoon. Indo-Gangetic Basin (IGB) exhibits high amount of PM2.5 (60− 200 μg m⁻³) throughout the year. The percentage differences between model simulated and observed PM2.5 are found higher (40− 60%) during winter, while lower (< 30%) during pre-monsoon and monsoon over most of the study locations. The weighted correlation coefficient between model simulated and observed PM2.5 is 0.81 at the significance of 98%. Associated RMSE (Root Mean Square Error) is 0.91 μg m⁻³. Large variability in vertically distributed PM2.5 are also found during pre-monsoon and monsoon. The study reveals that, model is able to capture the variabilities in spatial, seasonal and vertical distributions of PM2.5 over Indian region, however significant bias is observed in the model. PM2.5 mass concentrations are highest over West Bengal (82± 33 μg m⁻³) and the lowest in Jammu & Kashmir (14± 11 μg m⁻³). Annual mean of simulated PM2.5 mass over the Indian region is found to be 35± 9 μg m⁻³. Higher values of PM2.5 are found over the states, where the reported respiratory disorders are high. WRF-Chem simulated PM2.5 mass concentration gives a clear perspective of seasonal and spatial distribution of fine aerosols over the Indian region. The outcomes of the study have significant impacts on environment, human health and climate.
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