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351.
Environmental Geochemistry and Health - The study deals with the analyses of springs and wells at the base of Montepugliano Hill that represents the SE edge of the wide carbonate Matese massif...  相似文献   
352.
Area of habitat (AOH) is defined as the “habitat available to a species, that is, habitat within its range” and is calculated by subtracting areas of unsuitable land cover and elevation from the range. The International Union for the Conservation of Nature (IUCN) Habitats Classification Scheme provides information on species habitat associations, and typically unvalidated expert opinion is used to match habitat to land-cover classes, which generates a source of uncertainty in AOH maps. We developed a data-driven method to translate IUCN habitat classes to land cover based on point locality data for 6986 species of terrestrial mammals, birds, amphibians, and reptiles. We extracted the land-cover class at each point locality and matched it to the IUCN habitat class or classes assigned to each species occurring there. Then, we modeled each land-cover class as a function of IUCN habitat with (SSG, using) logistic regression models. The resulting odds ratios were used to assess the strength of the association between each habitat and land-cover class. We then compared the performance of our data-driven model with those from a published translation table based on expert knowledge. We calculated the association between habitat classes and land-cover classes as a continuous variable, but to map AOH as binary presence or absence, it was necessary to apply a threshold of association. This threshold can be chosen by the user according to the required balance between omission and commission errors. Some habitats (e.g., forest and desert) were assigned to land-cover classes with more confidence than others (e.g., wetlands and artificial). The data-driven translation model and expert knowledge performed equally well, but the model provided greater standardization, objectivity, and repeatability. Furthermore, our approach allowed greater flexibility in the use of the results and uncertainty to be quantified. Our model can be modified for regional examinations and different taxonomic groups.  相似文献   
353.
Environmental Fluid Mechanics - The influence of bottom roughness on the development of lock-release gravity currents is investigated through laboratory experiments using Particle Image...  相似文献   
354.
Environmental Science and Pollution Research - The conservation of ancient paintings sited in humid environments is an actual challenge for restorers, because it needs the knowledge of the...  相似文献   
355.

The spatial distribution of trace elements in surface sediments of the Hooghly estuary was studied over the monsoons in 2014–2017. As, Cd, Ni, Pb and U were two- to sixteen-fold the crust means with increasing levels toward the estuary, with Ni peak during the post-monsoon. Pearson’s correlation matrix, cluster analysis, enrichment factors and pollution index revealed the anthropic source and association of trace elements with Fe, Mn and Al and of Pb with U. Geoaccumulation index revealed for Ni an extremely contaminated situation at the estuary water during monsoon and for Cd a heavily contaminated situation at freshwater location. The potential contamination index was >6; thus, sediments were very severely contaminated by As, Cd and Ni with worst situation for As and Cd at fresh and brackish water and during post-monsoon. The overall ecological risk was severe, 300≤RI<600 at all sites and seasons, especially after the monsoon, at fluvial and brackish locations.

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356.
Environmental Science and Pollution Research - The growing demand for products with lower environmental impact and the extensive applicability of cellulose nanofibrils (CNFs) have received...  相似文献   
357.

Understanding the spatial distribution patterns of microplastics (plastics?<?5 mm) contributes to the assessment of sources and sinks of pollution thus providing information for the management of biota safety and overall ecosystem functionality. We chose a semi-closed study area, Lake Bracciano (Italy), to assess the environmental variability of contamination, focusing on the water compartment and the exposure of biota, specifically fish, by analysing the ingestion of microplastics. The focus of this study is to evaluate the concentration of microplastics in water (surface and column) across the lake and the ingestion of microplastics by two fish species of economic interest: Atherina boyeri and Coregonus lavaretus, inhabiting demersal and pelagic habitats respectively. Results show a surface contamination of 392,000?±?417,000 items km?2 and a column one of 0.76?±?1.00 items m?3. Fragments were the most abundant in surface while fibres in the column. Microplastics were found in C. lavaretus specimens, corresponding to contamination frequency of 5% and concentration of 0.15 items/fish. The main polymer found in water was polyethylene (81%); of minor percentages, there were various other polymers, including polystyrene and acrylic, which were also found in fish. As scientific literature provides few research where water and fish are simultaneously sampled, this investigation wants to contribute filling this knowledge gap by investigating for the first time a volcanic lake.

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358.

Heterogeneous photocatalysis is highlighted to treat volatile organic compound (VOC) emission. Then, this work analysed the influence of palladium (Pd) content loaded in TiO2 on n-octane and iso-octane photodegradation. For this, TiO2 was loaded with Pd in different contents: 0.4%, 0.7%, and 1.0%. The samples were characterized, and the photodegradation experiments were conducted by Pd/TiO2/UV process. The characterization analyses showed that the metal presence did not change the catalyst structure or its surface area; however, it reduced the bandgap energy. The photocatalytic results proved that palladium improved n-octane degradation from 62% (pure TiO2) to 92.6% (0.4%Pd/TiO2) and, iso-octane degradation enhanced from 59% (pure TiO2) to 90.6% (0.7%Pd/TiO2); all results were obtained in the space time of 39 s. Therefore, 0.4%Pd/TiO2 and 0.7%Pd/TiO2 showed better oxidation results to degradation n-octane and iso-octane, respectively. The kinetic model of pseudo-first order showed a good fit for the data of both VOCs. Heterogeneous photocatalysis with Pd/TiO2 showed to be an adequate technique to reduce VOCs emission.

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359.
Environmental Science and Pollution Research - In this work, graphene oxide (GO) was synthesized by the modified Hummers method. The nanomaterial was characterized by FTIR and Raman spectroscopy,...  相似文献   
360.
Environmental Science and Pollution Research - Exposure to air pollution during physical exercise is a health issue because fine particulate matter (dimension &lt; 10 μm; PM10) includes...  相似文献   
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