Search results for "Clima"
showing 10 items of 6069 documents
Lien entre démarrage de la saison des pluies et rendements agricoles observés/simulés du mil sur le site AMMA-CATCH.
2011
International audience
Date de semis du mil et variabilité intrasaisonnière des précipitations au Niger
2012
Le rôle du déterminisme pluviométrique, et plus spécifiquement du démarrage de la saison des pluies, sur les pratiques agricoles a été évalué à partir de l'exemple de la culture du mil dans la région de Niamey parce que celle-ci y occupe une place prépondérante. Cette analyse, à l'interface du climat et des sociétés, a été réalisée à partir d'enquêtes agronomiques conduites en milieu paysan sur l'observatoire AMMA-CATCH Niger sur un carré de100 km x 100 km au NE de Niamey entre 2004 et 2007. Par ailleurs, le démarrage de la saison des pluies repose sur des considérations subjectives qui dépendent fortement de l'utilisateur. Ainsi, ce dernier est de nature équivoque dans ces régions semi-ari…
Time and heat for sexual reproduction: comparing the phenology of Chara hispida of two populations at different latitudes
2017
Abstract Geographical location affects the main ecological factors driving the timing of plants’ life events. In addition, studying phenology is the simplest procedure to track current global warming and its effects on the success and survival of different populations of the same species. Little is known about the effect of water temperature and its corresponding accumulated heat on charophytes’ phenology. We compared differences in water temperature and sexual reproductive phenology of Chara hispida in two ponds of two countries located at different latitudes (Spain and Switzerland) over the same year. We estimated the accumulated heat required to develop from one phenophase to another (un…
Auditing Public Debt Using Risk Management
2023
The Audit Office of the Republic of Cyprus conducted the first-ever audit of the country’s public debt, seeking answers to two key questions. Is government debt sustainable, and is debt financing efficient and effective in securing the lowest cost with acceptable risks? The audit’s findings were discussed by the parliament and can have significant ramifications for public finance. However, public debt management is quite complex, and the International Organization of Supreme Audit Institutions suggests that sufficient technical knowledge is essential in undertaking an audit, including an understanding of the uncertain macroeconomy, financing conditions, and government fiscal stance. We use…
Degree Days and Building Energy Demand
2015
Degree-days (DD) are a climatic indicator that can be used in the assessment and analysis of weather related to energy consumption of buildings. Essentially, degree-days are a summation of the differences between the outdoor temperature and some reference (or base) temperature over a specific time period. In literature, different method can be used for determining the DD value and generally the choice depends on the availability of climatic data of each location. In this paper, after a review and comparison of the most common approaches used to determine DD, the Italian procedure was deeply analyzed. The application of Italian technical rules is based on weather data calculated on a monthly…
Sulla possibilità di estendere l'informazione climatica del passato attraverso le serie dendrocronologiche
2008
E’ noto che, a parte alcune eccezioni, la misura sistematica delle variabili meteorologiche in Italia ha avuto inizio a metà del XIX secolo. Non diversamente, in Sicilia si dispone di un numero limitato di serie storiche pluviometriche di consistenza pari a 100-120 anni e termometriche di 60-70 anni. L’obiettivo di una più approfondita conoscenza del clima passato, in Sicilia, può essere perseguito estendendo alcune serie storiche climatiche disponibili, mediante la dendroclimatologia, scienza che permette, attraverso l’analisi degli anelli annuali di accrescimento degli alberi, di legare l’entità di tale accrescimento alle cause che lo hanno generato e, in particolare, alle condizioni clim…
Denitrifying microbial communities along a boreal stream with varying land-use
2019
Streams have an important role in regulating nitrogen (N) transportation from terrestrial ecosystems to downstream waters. Here, we examined how catchment land-use affects potential denitrification rates and the function and composition of denitrifier communities in boreal stream sediments, using stable isotope incubations and qPCR and 454-pyrosequencing targeted on nirS, nirK and nosZ genes. Although land-use influenced the water chemistry as higher nitrite + nitrate (NO x − ) concentration at the agriculture-affected sampling point, sediment organic matter content was found to be the key factor in regulating potential denitrification rates. However, the abundance as well as the diversity …
Microbial Community Response on Wastewater Discharge in Boreal Lake Sediments
2017
Despite high performance, municipal wastewater treatment plants (WWTPs) still discharge significant amounts of organic material and nitrogen and even microbes into the receiving water bodies, altering physico-chemical conditions and microbial functions. In this study, we examined how nitrified wastewater affects the microbiology of boreal lake sediments. Microbial community compositions were assessed with next generation sequencing of the 16S rRNA gene, and a more detailed view on nitrogen transformation processes was gained with qPCR targeting on functional genes (nirS, nirK, nosZI, nosZII, amoAarchaea, and amoAbacteria). In both of the two studied lake sites, the microbial community compo…
Interlake variation and environmental controls of denitrification across different geographical scales
2013
Denitrification in lakes significantly reduces the nitrogen (N) load from land to oceans, but the factors controlling it remain poorly under- stood. Therefore, interlake variation of denitrification in sediments of small to medium-sized lakes (from 0.03 to 17.8 km 2 ) was studied across different geo- graphical scales. At the local scale, the denitrification rates and sediment microbial communities were studied in 4 boreal lakes in close proximity (within 20 km) using the isotope pairing technique (IPT) and molecular methods. These local scale data were com- bined with previously published data on denitrifica- tion rates from 10 other European lakes to extend the analysis to the regional (b…
Microbial communities in full-scale woodchip bioreactors treating aquaculture effluents.
2021
Woodchip bioreactors are being successfully applied to remove nitrate from commercial land-based recirculating aquaculture system (RAS) effluents. In order to understand and optimize the overall function of these bioreactors, knowledge on the microbial communities, especially on the microbes with potential for production or mitigation of harmful substances (e.g. hydrogen sulfide; H2S) is needed. In this study, we quantified and characterized bacterial and fungal communities, including potential H2S producers and consumers, using qPCR and high throughput sequencing of 16S rRNA gene. We took water samples from bioreactors and their inlet and outlet, and sampled biofilms growing on woodchips a…