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51.
Needles of two conifer species, Picea abies and Pinus nigra, were used as passive samplers for monitoring air contamination by sampling at increasing distances from a suspected point source of DDT. Needle concentrations declined with increasing distance downwind of the point source allowing to identify spatial and temporal trends of accumulation. This suggested that conifer needles are effective biomonitors of contamination levels in areas characterized by the presence of semi-volatile substances. Differences in uptake were apparent between the species. Needle morphology and structure were studied with scanning electron microscope (SEM) as were dimensional parameters (surface area, volume). The results suggest that the concentrations depend on a mechanism involving the inner structure of the needles, specifically the number and accessibility of resin channels rather than their surface area. Pine needles have more channels with greater accessibility than spruce. The results suggest that spruce is more suitable for short term measurement while pine for determining long term cumulative exposure. 相似文献
52.
Davide Viaggi 《Journal of Environmental Planning and Management》2015,58(12):2082-2087
53.
Tagliapietra D Cornello M Volpi Ghiradini A Ghirardini AV 《Environment international》2005,31(7):1089-1093
In this study, the use of reduced assemblages of benthic invertebrate taxa is proposed to describe similarity relationships between samples from transitional environments. A data set from four different studies, made up of 641 samples for a total 203 species, was analysed using permutation randomisation tests in order to extract a pool of taxa able to approximate the full set of species. The identified "operational set", comprising 19 taxa, was capable of adequately reproduce similarity relationships between samples (Rho>0.90, p<0.001). All selected taxa were easily extractable from the samples and easy identifiable by non-specialised technicians; these characteristics were considered appropriate for the development of rapid and cost-effective monitoring procedures based on benthic invertebrate assemblages. 相似文献
54.
Assessing barriers to effective spatial planning in Mauritius. A combination of SWOT and gap surveys
Parenivel Pillay Mauree Davide Geneletti 《Journal of Environmental Planning and Management》2017,60(8):1324-1346
This paper examines the barriers to effective spatial planning in Mauritius. With its competitive advantage, due to its strategic position into Africa, the island is experiencing rapid development. However, current land development, especially considering land scarcity, reflects a lack of integrated strategic decision-making in the spatial planning system in Mauritius. Using a PESTLE framework and two quantitative surveys, namely a SWOT analysis addressed to the planners in Mauritius, followed by a gap analysis addressed to a wider group of professionals, the barriers have been identified. The result shows that overall significant barriers exist. The contributions of the research have been: first, in the methods adopted to identify such barriers towards effective spatial planning; second, in the identification of the barriers in order of importance; and third, in the formulation of strategies to address these barriers. 相似文献
55.
Elisa De Laurentiis Marco Minella Valter Maurino Claudio Minero Davide Vione 《Environmental science and pollution research international》2014,21(20):11770-11780
Information concerning the link between surface-water photochemistry and climate is presently very scarce as only a few studies have been dedicated to the subject. On the basis of the limited knowledge that is currently available, the present inferences can be made as follows: (1) Warming can cause enhanced leaching of ionic solutes from the catchments to surface waters, including cations and more biologically labile anions such as sulphate. Preferential sulphate biodegradation followed by removal as organic sulphides in sediment could increase alkalinity, favouring the generation of the carbonate radical, CO3 ·?. However, this phenomenon would be easily offset by fluctuations of the dissolved organic carbon (DOC), which is strongly anticorrelated with CO3 ·?. Therefore, obtaining insight into DOC evolution is a key issue in understanding the link between photochemistry and climate. (2) Climate change could exacerbate water scarcity in the dry season in some regions. Fluctuations in the water column could deeply alter photochemistry that is usually favoured in shallower waters. However, the way water is lost would strongly affect the prevailing photoinduced processes. Water outflow without important changes in solute concentration would mostly favour reactions induced by the hydroxyl and carbonate radicals (·OH and CO3 ·?). In contrast, evaporative concentration would enhance reactions mediated by singlet oxygen (1O2) and by the triplet states of chromophoric dissolved organic matter (3CDOM*). (3) In a warmer climate, the summer stratification period of lakes would last longer, thereby enhancing photochemical reactions in the epilimnion but at the same time keeping the hypolimnion water in the dark for longer periods. 相似文献
56.
In human dominated landscapes, ecosystems are under increasing pressures caused by urbanization and infrastructure development.
In Alpine valleys remnant natural areas are increasingly affected by habitat fragmentation and loss. In these contexts, there
is a growing risk of local extinction for wildlife populations; hence assessing the consequences on biodiversity of proposed
land use changes is extremely important. The article presents a methodology to assess the impacts of land use changes on target
species at a local scale. The approach relies on the application of ecological profiles of target species for habitat potential
(HP) assessment, using high resolution GIS-data within a multiple level framework. The HP, in this framework, is based on
a species-specific assessment of the suitability of a site, as well of surrounding areas. This assessment is performed through
spatial rules, structured as sets of queries on landscape objects. We show that by considering spatial dependencies in habitat
assessment it is possible to perform better quantification of impacts of local-level land use changes on habitats. 相似文献
57.
Tassi Franco Garofalo Paolo S. Turchetti Filippo De Santis Davide Capecchiacci Francesco Vaselli Orlando Cabassi Jacopo Venturi Stefania Vannini Stefano 《Environmental geochemistry and health》2022,44(7):1925-1948
Environmental Geochemistry and Health - This study focuses on the geochemical features of the presently discharging thermal and cold springs and on paleofluids from the upstream portion of the Reno... 相似文献
58.
Over recent years, technical developments resulting in the feasibility of fetal cardiovascular magnetic resonance (CMR) have provided a new diagnostic tool for studying the human fetal heart and circulation. During the same period, we have witnessed the arrival of several minimally invasive fetal cardiac interventions (FCI) as a possible form of treatment in selected congenital heart diseases (CHDs). The role of fetal CMR in the planning and monitoring of FCI is not yet clear. Indeed, high-quality fetal CMR is not available or routinely offered at most centers caring for patients with prenatally detected CHD. However, in theory, fetal CMR could have much to offer in the setting of FCI by providing complementary anatomic and physiologic information relating to the specific intervention under consideration. Similarly, fetal CMR may be useful as an alternative imaging modality when ultrasound is hampered by technical limitations, for example, in the setting of oligohydramnios and in late gestation. In this review, we summarize current experience of the use of fetal CMR in the diagnosis and monitoring of fetuses with cardiopathies in the setting of a range of invasive in utero cardiac and vascular interventions and medical treatments and speculate about future directions for this versatile imaging medium. 相似文献
59.
60.
Minero C Bono F Rubertelli F Pavino D Maurino V Pelizzetti E Vione D 《Chemosphere》2007,66(4):650-656
This paper studies the pH effect on the photonitration of catechol, 1-naphthol, naphthalene, and benzene. The pH trend is influenced by the generation of HNO(2) and peroxynitrous acid (HOONO) upon nitrate photolysis. HNO(2) can be involved in a direct and an indirect nitration process. Direct nitration follows the pH distribution of HNO(2) (flexus around 3). Indirect nitration, possibly involving nitrosation+oxidation, would be highest around pH3. HOONO can be involved in electrophilic nitration, where the initial formation rate of the nitroderivatives is proportional to [H(+)], or take part in nitration directly, in which case a less important pH effect in photonitration is observed. The relative importance of the various nitration pathways for each substrate determines the resulting pH effect in photonitration upon nitrate photolysis. 相似文献