Search results for "Spatial"
showing 10 items of 2121 documents
Nitrous oxide emission by agricultural soils: a review of spatial and temporal variability for mitigation
2012
CT3 ; EnjS4; International audience; This short review deals with soils as an important source of the greenhouse gas N2O. The production and consumption of N2O in soils mainly involve biotic processes: the anaerobic process of denitrification and the aerobic process of nitrification. The factors that significantly influence agricultural N2O emissions mainly concern the agricultural practices (N application rate, crop type, fertilizer type) and soil conditions (soil moisture, soil organic C content, soil pH and texture). Large variability of N2O fluxes is known to occur both at different spatial and temporal scales. Currently new techniques could help to improve the capture of the spatial va…
Carbon use efficiency variability from MODIS data
2017
[EN] Carbon use efficiency (CUE) describes how efficiently plants incorporate the carbon fixed during photosynthesis into biomass gain and can be calculated as the ratio between net primary production (NPP) and gross primary production (GPP). In this work, annual CUE has been obtained from annual GPP and NPP MODIS products for the peninsular Spain study area throughout eight years. CUE is spatially and temporally analyzed in terms of the vegetation type and annual precipitation and annual average air temperature. Results show that dense vegetation areas with moderate to high levels of precipitation present lower CUE values, whereas more arid areas present the highest CUE values. However, th…
Primi dati sull’uso dell’habitat in una popolazione siciliana di Natrix natrix.
2013
First data about the habitat use in a population of Natrix natrix from Sicily. In the present paper the preliminary results of an investigation carried out on a Sicilian population of the grass snake (Natrix natrix) are reported. The leading aim of this study is to compare habitat use among three different classes of individuals (males, females, immatures), using as input the density of observations in four habitat types. Field studies were conducted beside a reservoir (“Lago di Scanzano”), located about 40 km from Palermo (western Sicily). Our results indicate spatial and temporal differences among groups. Young individuals were observed more frequently between April and May along wet mead…
ASSESSING NEIGHBORHOOD DISORDER: VALIDATION OF A THREE-FACTOR OBSERVATIONAL SCALE
2015
AbstractThis study presents data on the development and preliminary validation of an observational scale assessing neighborhood disorder. Independent observations by trained raters of neighborhood disorder were conducted in 552 census block groups in the city of Valencia (Spain). Intraclass correlation coefficients assessing inter-rater reliability indicated fair to substantial levels of agreement among raters. Confirmatory factor analyses supported a final three-factor model scale measuring physical disorder, social disorder, and physical decay. Results for the internal consistency showed large composite reliability indices indicating good reliability for all neighborhood disorder factors.…
Evaluación del desorden en los vecindarios: validación de una escala observacional de tres factores
2015
This study presents data on the development and preliminary validation of an observational scale assessing neighborhood disorder. Independent observations by trained raters of neighborhood disorder were conducted in 552 census block groups in the city of Valencia (Spain). Intraclass correlation coefficients assessing inter-rater reliability indicated fair to substantial levels of agreement among raters. Confirmatory factor analyses supported a final three-factor model scale measuring physical disorder, social disorder, and physical decay. Results for the internal consistency showed large composite reliability indices indicating good reliability for all neighborhood disorder factors. Evidenc…
Quantum Finite One-Counter Automata
1999
In this paper the notion of quantum finite one-counter automata (QF1CA) is introduced. Introduction of the notion is similar to that of the 2-way quantum finite state automata in [1]. The well-formedness conditions for the automata are specified ensuring unitarity of evolution. A special kind of QF1CA, called simple, that satisfies the well-formedness conditions is introduced. That allows specify rules for constructing such automata more naturally and simpler than in general case. Possible models of language recognition by QF1CA are considered. The recognition of some languages by QF1CA is shown and compared with recognition by probabilistic counterparts.
Analysis of a spatial orientation memory in Drosophila.
2008
Flexible goal-driven orientation requires that the position of a target be stored, especially in case the target moves out of sight. The capability to retain, recall and integrate such positional information into guiding behaviour has been summarized under the term spatial working memory. This kind of memory contains specific details of the presence that are not necessarily part of a long-term memory. Neurophysiological studies in primates indicate that sustained activity of neurons encodes the sensory information even though the object is no longer present. Furthermore they suggest that dopamine transmits the respective input to the prefrontal cortex, and simultaneous suppression by GABA s…
Viaggi nell’immaginario: il turismo virtuale nel sito UNESCO di Tarragona
2023
Le nuove tecnologie hanno trasformato in modo radicale non solo la geografia come disciplina, ma anche le geografie del mondo. Il digitale ha assunto, infatti, un ruolo di mediazione sempre più pervasivo nella produzione dello spazio, come delle conoscenze e degli immaginari geografici. Le possibilità offerte dal virtuale, in particolare, offrono oggi un contributo decisivo nella comunicazione dei significati attribuiti ai luoghi e rispondono in modo sempre più efficace ai bisogni emergenti del settore turistico. Le esperienze di visita mediate dal digitale mirano a coinvolgere i sensi e risultano efficaci quando promuovono immersioni rigorosamente realistiche. Nel quadro di queste riflessi…
Food plant diversity as broad-scale determinant of avian frugivore richness.
2007
The causes of variation in animal species richness at large spatial scales are intensively debated. Here, we examine whether the diversity of food plants, contemporary climate and energy, or habitat heterogeneity determine species richness patterns of avian frugivores across sub-Saharan Africa. Path models indicate that species richness of Ficus (their fruits being one of the major food resources for frugivores in the tropics) has the strongest direct effect on richness of avian frugivores, whereas the influences of variables related to water–energy and habitat heterogeneity are mainly indirect. The importance of Ficus richness for richness of avian frugivores diminishes with decreasing sp…
Mapping field-scale spatial patterns of size and activity of the denitrifier community
2009
International audience; There is ample evidence that microbial processes can exhibit large variations in activity on a field scale. However, very little is known about the spatial distribution of the microbial communities mediating these processes. Here we used geostatistical modelling to explore spatial patterns of size and activity of the denitrifying community, a functional guild involved in N-cycling, in a grassland field subjected to different cattle grazing regimes. We observed a non-random distribution pattern of the size of the denitrifier community estimated by quantification of the denitrification genes copy numbers with a macro-scale spatial dependence (6–16 m) and mapped the dis…