Search results for "Spatial"
showing 10 items of 2121 documents
L-band vegetation optical depth seasonal metrics for crop yield assessment
2018
Attenuation of surface microwave emission due to the overlying vegetation is proportional to the density of the canopy and to its water content. The vegetation optical depth (VOD) parameter measures this attenuation. VOD could be a valuable source of information on agroecosystems, especially at lower frequencies for which greater portion of the vegetation canopy contributes to the observed brightness temperature. In the past, visible-infrared indices have been used to provide yield estimates based on measuring the photosynthetic activity from the surface canopy layer. These indices are affected by clouds and apply only in the presence of solar illumination. In this study we instead use the …
Effects of spatial scale and vegetation cover on predation of artificial ground nests
1995
Scale-dependent effects of landscape heterogeneity on predation of artificial ground nests were studied. Two spatial scales were selected: landscape grain size and single stand size. The landscape types did not differ from each other in their total predation intensity. Depredation was highest in larger stands in all the landscape types studied and the highest predation rate was detected in the largest stands within the most fragmented landscapes. This is possibly due to concentration of rodent-eating predators from surrounding open areas into large stands in the study year when their main prey, voles, crashed. In crash years, alternative predation on e.g. forest bird nests may play an impor…
Grapevine physiological response to row orientation-induced spatial radiation and microclimate changes
2020
Terroir factors and vineyard practices largely determine canopy and root system functioning. In this study, changes in soil conditions, multi-level (vertical, horizontal) light interception (quantitative, photographic, schematic, 3D modelled), leaf water potential and photosynthetic activity were measured during the grape ripening period on NS, EW, NE-SW, and NW-SE orientated (Southern Hemisphere) vertically trellised Shiraz grapevine canopies. It was hypothesised that the spatial radiation interception angle and radiation distribution of differently orientated and vertically trained grapevine rows would affect soil conditions and vine physiological activity. Soil water content showed an in…
Spatial Gradients of Intensity and Persistence of Soil Water Repellency Under Different Forest Types in Central Mexico
2016
Organic residues release hydrophobic compounds to the soil that may induce soil water repellency (WR), which may inhibit infiltration and increase runoff and soil loss rates. Although there are many studies on soil WR through the world, very few investigations have been conducted in Mexican areas. This paper studies the natural background of soil WR in soils from central Mexico under representative forest types, analyzing the spatial distribution of soil WR in relation with tree canopy, vegetation cover and main soil chemical (pH, CaCO3, organic C content and exchangeable cations) and physical properties (texture). The water drop penetration time and the ethanol tests were used to assess pe…
Carlo Scarpa e la sala del dubbio di palazzo Abatellis
2016
Questo articolo descrive, da un disegno di studio e da foto d'archivio, la sala del dubbio in divenire al processo di progettazione. E' uno sguardo alla realizzazione di Scarpa con la consapevolezza che le forme e gli allestimenti di palazzo Abatellis, stabiscono alla scala di dettaglio; "raccontare" di possibili somiglianze tra il dispositivo e le relazioni spaziali che si instaura con gli occhi del visitatore. This paper describes, from a study design and the photo archive, the challenge of the lost set-up in the making that the design process. It's a look at the making Scarpa with the knowledge that forms and exhibitions for Abatellis palace, established the scale of detail; "recount" of…
Heterogeneity of host-parasite relationships : ecological and evolution significance
2005
Although parasites have been studied for a long time, the major knowledge concern parasite which have medical or veterinary interest. Whereas they are omnipresent in the nature, the role of parasite infections on natural populations is poorly understood. One of the aim of this work was to study the pathogenicity of two groups of parasites (ticks and Haemosporidae) among natural populations of blackbirds. The study revealed that both parasites are associated with body condition and immune response. However, the study of an urban blackbird population did not confirm the effect of Haemosporidae on the survey and on the population dynamic.The impact of spatial pattern on the relation between ho…
Gènes fongiques liés au calcium impliqués dans la mycorhize à arbuscules
2012
Fluctuations in intracellular (Ca2+) calcium levels generate signaling events and regulate different cellular processes. Whilst the implication of Ca2+ in plant cell responses during arbuscular mycorrhiza (AM) interactions is well documented, nothing is known about the regulation or role of this secondary meesenger in the fungal symbiont. The molecular basis of fungal calcium homeostasis in the AM symbiosis was analyzed by investigating the expression of Ca2+-related fungal genes. In a first study, G. mosseae genes putatively encoding a MAP3k-like protein kinase (Gm2) and a P-type ATPase (Gm152) were investigated. Both Ca2+-related genes were up-regulated by A. sinicum root exudates, sugges…
Constraint Cellular Automata for Urban Development Simulation: An Application to the Strasbourg-Kehl Cross-Border Area
2017
AcknowledgementsThe research presented in this chapter is part of the Smart. Boundary project supported by the Fonds National de la Recherche in Luxembourg and CNRS in France (ref. INTER/CNRS/12/02). The authors would like also to thank the Grasp Program of LISER for allowing cross-collaboration between the two teams based in Luxembourg and France.; International audience; Urban sprawl and space consumption have become key issues in sustainable territorial development. Traditional planning approaches are often insufficient to anticipate their complex spatial consequences, especially in cross-border areas. Such complexity requires the use of dynamic spatial simulations and the development of…
Cellular automata and urban development simulation : a transition rules creation process based on statistical analysis
2015
National audience; Nowadays land use evolution study has become a major stake in urban planning. The main focus is to understand the way in which land use evolves across time and to understand processes that take place. This understanding would allow to plan urban developments based on a knowledge as complete as possible covering as many fields as possible (i.e. urban planning, politics, sociology, etc.). Simulation tools can be used to merge and display different points of view and stakes from different stakeholders (Parrott & Meyer, 2012).
Évolution des températures observées en Bourgogne (1961-2011)
2014
International audience; Depuis un demi-siècle environ, l’augmentation des concentrations atmosphériques en gaz à effet de serre a entraîné une élévation de température qui peut être analysée selon des échelles emboîtées, allant de la planète aux territoires. Dans cette étude, les mesures effectuées sur le réseau de stations Météo-France sont mobilisées pour analyser la température en Bourgogne sur la période 1961-2011. Le réchauffement observé a des caractéristiques très proches des moyennes françaises. Il est plus fort que sur la moyenne planétaire. Il est marqué par une rupture nette délimitant deux périodes bien différentes : 1961-1987 et 1988-2011. Une interpolation par régression krige…