Search results for " Impact."
showing 10 items of 1051 documents
How do drought and rain events impact soil microbial communities greenhouse gas production?
2011
Affiche, résumé. Session GC: Microbes in the Changing Environmenl: Global Climate Change and Soil under Human Impact; International audience
Quantitative x-ray diffraction phase analysis of coarse airborne particulate collected by cascade impactor sampling
1997
Mineralogical composition of Castellon (Spanish Mediterranean coast) atmospheric aerosol was studied by X-ray diffraction by sampling with a cascade impactor without filters. Quantitative phase analysis of natural phases present in the atmospheric coarse aerosol was performed using a modified version of the computer program MENGE, that uses the standardless X-ray method developed by Rius for the quantitative analysis of multiphase mixtures, adapted for PC running. Presence of quartz, calcite and gypsum was identified in the atmospheric aerosol and we have quantified their amounts using the standardless method.
Tracing the fate of microplastic carbon in the aquatic food web by compound-specific isotope analysis
2019
Increasing abundance of microplastics (MP) in marine and freshwaters is currently one of the greatest environmental concerns. Since plastics are fairly resistant to chemical decomposition, breakdown and reutilization of MP carbon complexes requires microbial activity. Currently, only a few microbial isolates have been shown to degrade MPs, and direct measurements of the fate of the MP carbon are still lacking. We used compound-specific isotope analysis to track the fate of fully labelled 13C-polyethylene (PE) MP carbon across the aquatic microbial-animal interface. Isotopic values of respired CO2 and membrane lipids showed that MP carbon was partly mineralized and partly used for cell growt…
Erosion en milieu sableux cultivé au Niger : dynamique actuelle et passée en liaison avec la pression anthropique et les changements climatiques
2011
Sahelian ecosystems, especially those installed on sandy soils react very quickly and intensely to small climatic changes. In this semi-arid area, wind erosion which occurs mainly on cultivated millet fields and is threatening the sustainable use of land resources. Furthermore, the rapid population growth and the severe droughts of the twentieth century have had important impacts on ecosystems. To better manage this fragile environment, it is important first to understand how it works. This thesis was included in the framework of the AMMA project (African Monsoon Multidisciplinary Analyses) and was in the heart of a CORUS 2 (Coopération pour la Recherche Universitaire et Scientifique) progr…
Novel Version of PageRank, CheiRank and 2DRank for Wikipedia in Multilingual Network Using Social Impact
2020
International audience; Nowadays, information describing navigation behaviour of internet users are used in several fields, e-commerce, economy, sociology and data science. Such information can be extracted from different knowledge bases, including business-oriented ones. In this paper, we propose a new model for the PageRank, CheiRank and 2DRank algorithm based on the use of clickstream and pageviews data in the google matrix construction. We used data from Wikipedia and analysed links between over 20 million articles from 11 language editions. We extracted over 1.4 billion source-destination pairs of articles from SQL dumps and more than 700 million pairs from XML dumps. Additionally, we …
Solitary Rectal Ulcer
1979
Solitary ulcers of the rectum may be traumatic in origin and caused by thermometers, occasionally by digital removal of a fecal impaction, or by deviate sexual behavior. Solitary rectal ulcers may also be a manifestation of Crohn’s disease. Very rarely, ectopic gastric mucosa is their cause. For the vast majority of solitary rectal ulcers, the explanation remains unknown. Occasionally, the ulcers are accompanied by localized inflammation of the mucosa within the distal segment of the rectum with edema, erythema, and circumscribed whitish flecks in a thickened bowel wall covered by excessive secretions. The changes are found predominantly in the ventral portion of the rectum, and in contrast…
Climate Change and Energy Issues in the North
2011
Highly industrialized societies are mostly responsible for the emerging anthropogenic climate change. There are different ways to measure this responsibility (e.g., whether based on causal contribution or strict responsibility, see Muller et al. 2007). However, regardless of the specific method applied to measure the impact, presently, the USA and the EU are the global leaders in green house gas emissions with countries such as China, India and Brazil following closely behind. Globally, GHG emissions are still increasing among the highly industrialized countries, particularly in the USA – a country that never ratified the Kyoto Protocol. However, the EU has managed to curb its emissions, co…
Análisis de la evolución de la línea de costa entre Alcossebre y Orpesa a partir de fotografía aérea (1956-2015)
2019
[ES] El artículo presenta un análisis de la evolución de la línea de costa entre Alcossebre y Orpesa, a partir de fotografías aéreas y ortofotografías, entre 1956 y 2015. La digitialización de 12 líneas de costa ha permitido calcular los cambios netos y máximos, así como la tasa de cambio entre los diferentes años. Los resultados muestran una costa recesiva, con una gran variabilidad espacio-temporal. Conviven sectores con crecimiento sostenido provocado por la acción antrópica (deriva arriba de los espigones y regeneraciones de playa) o causas naturales (prominencias costeras), con otros claramente erosivos (deriva abajo de espigones). Además, el análisis de las isobatas del estrán sumergi…
Stakeholders’ Attitudes about the Transplantations of the Mediterranean Seagrass Posidonia oceanica as a Habitat Restoration Measure after Anthropoge…
2021
Anthropogenic impacts on Posidonia oceanica meadows have led to a decline of this ecosystem throughout the Mediterranean. Transplantations have often been prescribed as a compensation measure to mitigate the impacts caused by coastal maritime works. Here a Q methodology approach was used to investigate the stakeholders’ attitudes in four case studies of P. oceanica transplants realized in Italian waters. Twenty-two respondents were asked to score 37 statements, and the resultant Q-sorting was analyzed via an inverse PCA using the KADE software. Four discourses, corresponding to the significant axes in the factorial analysis were identified: science and conservation (F1), oriented at a rigor…
The economic impact of water taxes: a computable general equilibrium analysis with an international data set
2008
Water is scarce in many countries. One instrument for improving the allocation of a scarce resource is (efficient) pricing or taxation. However, water is implicitly traded on international markets, particularly through food and textiles, so that the impacts of water taxes cannot be studied in isolation, but require an analysis of international trade implications. We include water as a production factor in a multi-region, multi-sector computable general equilibrium model (GTAP), to assess a series of water tax policies. We find that water taxes reduce water use and lead to shifts in production, consumption and international trade patterns. Countries that do not levy water taxes are nonethele…