193 research outputs found
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Recent Developments in Alcoholic Beverage Labeling Regulation
In light of the ubiquitous âNutrition Factsâ labels that appear on food products and non-alcoholic beverages, it is surprising to some people that there is not a standard label on alcoholic beverages containing information about alcohol and nutritional content. In 2007, the Alcohol and Tobacco Tax and Trade Bureau (âTTBâ)âthe federal agency within the Department of the Treasury tasked with regulating alcoholic beveragesâissued a notice of proposed rulemaking to require alcohol and nutritional content to appear on alcoholic beverage labels. Extensive public comments were submitted on the proposed rule, and more than three years have passed, but it is unclear if and when the TTB will issue a final rule. This note describes the recent history of TTBâs efforts to close this âregulatory gapâ with respect alcoholic beverage labeling. Additionally, this note explores the unique balance of state and federal authority with respect to alcoholic beverage labeling, and how a more detailed federal label mandate may affect this balance. Special attention is paid to whether a federal label would âpre-emptâ state label regulations
Spatial uncertainty effects on a species-landscape relationship model in ecology
In this study, we explore the effects of geometrical uncertainty in an existing species-landscape relationship model in the hoverfly communities. We also investigate how geometrical uncertainties affect a more complex model including both current forest patch features and past forest features. Because of a possible time-lag in biological responses to forest changes such as fragmentation, the historical dimension is added to the first model. The proposed approach relies on three spatial sources enabling to get forest fragments at different times: historical map (~1850), aerial black and white photographs (1954) and orthorectified photographs (2010). Firstly, we analyze the effect of the spatial data production method (manual versus automatic) on models using current forest patches only. Then, we build a more complex model including past changes in forest size. As previously, the effect of production-based uncertainty was assessed by comparing the models based on forests extracted manually and automatically. We address finally the impact of positional accuracy on the historical map by using a Monte Carlo simulation approach. Global results show that responses of the statistical models are strongly affected by spatial uncertainty in inputs
Estimating taxonomic diversity and functional types of perennial forage grasses in mountain meadows: potentialities of Pléiades imagery
Estimating taxonomic diversity and functional types of perennial forage grasses in mountain meadows: potentialities of Pléiades imagery
Discriminating small wooded elements in rural landscape from aerial photography: a hybrid pixel/object-based analysis approach
While small, fragmented wooded elements do not represent a large surface area in
agricultural landscape, their role in the sustainability of ecological processes is
recognized widely. Unfortunately, landscape ecology studies suffer from the lack
of methods for automatic detection of these elements. We propose a hybrid
approach using both aerial photographs and ancillary data of coarser resolution
to automatically discriminate small wooded elements. First, a spectral and textural
analysis is performed to identify all the planted-tree areas in the digital photograph.
Secondly, an object-orientated spatial analysis using the two data sources
and including a multi-resolution segmentation is applied to distinguish between
large and small woods, copses, hedgerows and scattered trees. The results show the
usefulness of the hybrid approach and the prospects for future ecological
applications
PrĂ©diction des services Ă©cosystĂ©miques dans les bois agricoles Ă partir dâimages hyperspectrales
Les services Ă©cosystĂ©miques sont devenus un enjeu social, Ă©cologique et Ă©conomique majeur dans le monde. Les forĂȘts des paysages agricoles offrent des services prĂ©cieux bien qu'ils soient souvent sous-estimĂ©s et mal utilisĂ©s. Cependant, une cartographie prĂ©cise de ces services Ă grande Ă©chelle reste difficile. Des donnĂ©es de tĂ©lĂ©dĂ©tection permettent aujourdâhui dâenvisager cette cartographie. Nous avons Ă©valuĂ© la contribution des indices de vĂ©gĂ©tation calculĂ©s Ă partir d'images hyperspectrales Ă haute rĂ©solution spatiale pour la prĂ©vision de services Ă©cosystĂ©miques par rapport aux rĂ©sultats fondĂ©es sur la couverture terrestre. 28 parcelles forestiĂšres ont Ă©tĂ© Ă©chantillonnĂ©es et des images hyperspectrales aĂ©roportĂ©es ont Ă©tĂ© acquises pour la zone d'Ă©tude, Ă une rĂ©solution de 2 m. Habituellement, les indices de vĂ©gĂ©tation dĂ©rivĂ©s de l'hyperspectral Ă lâĂ©chelle du paysage (buffer spatial autour de lâobjet considĂ©rĂ©) sont rĂ©duits en utilisant des statistiques descriptives (moyenne, Ă©cart-type, valeurs minimales et maximales). Cependant, cette approche peut perdre beaucoup d'informations, en particulier Ă l'Ă©chelle des paysages, oĂč plusieurs objets avec diffĂ©rentes signatures spectrales sont prĂ©sents. Nous proposons une description du paysage hyperspectral basĂ©e sur la rĂ©partition complĂšte des indices de vĂ©gĂ©tation Ă travers les paysages. Nous avons utilisĂ© les modĂšles de mĂ©lange gaussien (GMM) pour modĂ©liser la distribution des pixels dans chaque paysage et introduit une distance L2 entre ces mĂ©langes. Cette distance est utilisĂ©e dans lâalgorithme des plus proches voisins pour prĂ©dire les niveaux de services. La qualitĂ© des prĂ©dictions a Ă©tĂ© comparĂ©e entre trois reprĂ©sentations de paysage: occupation des sols, statistiques descriptives de donnĂ©es hyperspectrales et description de donnĂ©es hyperspectrales basĂ©es sur GMM
Object-based classification of grasslands from high resolution satellite image time series using gaussian mean map kernels
This paper deals with the classification of grasslands using high resolution satellite image time series. Grasslands considered in this work are semi-natural elements in fragmented landscapes, i.e., they are heterogeneous and small elements. The first contribution of this study is to account for grassland heterogeneity while working at the object level by modeling its pixels distributions by a Gaussian distribution. To measure the similarity between two grasslands, a new kernel is proposed as a second contribution: the a-Gaussian mean kernel. It allows one to weight the influence of the covariance matrix when comparing two Gaussian distributions. This kernel is introduced in support vector machines for the supervised classification of grasslands from southwest France. A dense intra-annual multispectral time series of the Formosat-2 satellite is used for the classification of grasslandsâ management practices, while an inter-annual NDVI time series of Formosat-2 is used for old and young grasslandsâ discrimination. Results are compared to other existing pixel- and object-based approaches in terms of classification accuracy and processing time. The proposed method is shown to be a good compromise between processing speed and classification accuracy. It can adapt to the classification constraints, and it encompasses several similarity measures known in the literature. It is appropriate for the classification of small and heterogeneous objects such as grasslands
The influence of spatial and temporal discontinuities of forest habitats on the current presence of flightless saproxylic beetles
Flightless saproxylic beetles were selected in order to study the impact of temporal and spatial discontinuity of forests. They were chosen because: (1) they are unable to fly, making them dispersal-limited species, (2) they have a saproxylic diet, which means they are closely linked to the forest, and (3), they have rarely been studied. Forest temporal continuity was expected to be the main factor explaining the presence of these species, modulated by the
past and present amount of forest in the surrounding landscape. Twenty-seven forests, distributed into three zones, were sampled in southwestern France. Flightless saproxylic beetles were surveyed using a Winkler extractor and a Berlese funnel. Their presence/absence were modelled using generalised linear mixed models, with zone variable as random effect. Two species showed significant zone effect and were only or more present in the zone with
the highest present forest amount in a 0.5 km radius. In the model that converged, the only selected variable was the past amount of forest in the landscape. The size of the forest, the presence of dead wood and the forest temporal continuity were not included in this model. The importance of the amount of forest in the landscape supports the hypothesis that dispersal-limited species are affected by landscape characteristics. This study demonstrates an important link between the presence of Dienerella clathrata and the amount of forest in
the past, which led to an indicator species analysis being performed
Utilisation des sĂ©ries temporelles dâimages Sentinel-2 pour la cartographie de lâoccupation du sol dans un contexte de modĂ©lisation de la biodiversitĂ©
La connaissance de lâoccupation du sol actualisĂ©e est une donnĂ©e essentielle pour de nombreuses applications
scientifiques et opĂ©rationnelles. Ă ce titre, il sâagit dâune donnĂ©e permettant de dĂ©river plusieurs variables
essentielles de biodiversitĂ©, telles que lâĂ©tendue et la fragmentation des Ă©cosystĂšmes ainsi que la structure
paysagĂšre, variables fortement reliĂ©es au potentiel de biodiversitĂ© dâun paysage (Skidmore et al., 2015). Elle
reprĂ©sente une donnĂ©e dâentrĂ©e essentielle des modĂšles prĂ©dictifs ou de simulation paysagĂšre dĂ©veloppĂ©es en
recherche en Ă©cologie du paysage. Ă lâheure actuelle, il existe plusieurs jeux de donnĂ©es dâoccupation du sol de
rĂ©fĂ©rence, comme Corine Land Cover (CLC) Ă lâĂ©chelle europĂ©enne ou la BD TOPOÂź de lâIGN Ă lâĂ©chelle
nationale française. Ces deux jeux de donnĂ©es permettent de dĂ©crire lâoccupation du sol de maniĂšre exhaustive
et harmonisée sur de larges étendues géographiques. Cependant, la faiblesse de CLC réside dans sa fraßcheur
temporelle, Ă savoir que sa diffusion intervient tardivement par rapport Ă la pĂ©riode temporelle quâelle dĂ©crit. Si
CLC dispose dâune typologie trĂšs dĂ©taillĂ©e, intĂ©grant des notions dâusage du sol, la BD TOPOÂź, si elle dĂ©crit
prĂ©cisĂ©ment les Ă©lĂ©ments permanents du paysage, nâidentifie pas diffĂ©rentes classes annuelles du paysage
telles que les cultures. LâavĂšnement rĂ©cent de la mission spatiale Sentinelle-2 qui fournit de sĂ©ries temporelles
dâimages satellites, Ă forte capacitĂ© de revisite (5 jours) et une rĂ©solution spatiale dĂ©camĂ©trique sur lâensemble
de la surface terrestre, ouvre ainsi de nouvelles opportunitĂ©s dans la cartographie de lâoccupation du sol
actualisĂ©e Ă grande Ă©chelle. Dans ce sens, le CESBIO avec des contributions de lâUMR Dynafor, dans le cadre
du centre dâexpertise scientifique « Occupation du Sol » (CES OSO) du PĂŽle ThĂ©matique Surfaces
Continentales THEIA a dĂ©veloppĂ© une chaĂźne opĂ©rationnelle de classification supervisĂ©e automatique dâimages
Sentinelle-2 et Landsat-8 (iota2) produisant une cartographie de lâoccupation du sol actualisĂ©e. Lâoccupation du
sol est dĂ©crite grĂące Ă 17 classes, couvrant les grands ensembles paysagers (urbain, agricole et semi-naturel), Ă
une résolution spatiale de 10 m et une unité minimale de collecte de 0.01 ha (UMC). La précision globale proche
de 90% permet son utilisation tant dans des contextes opĂ©rationnels et scientifique dâaide Ă la dĂ©cision (Inglada
et al., 2017). Cette présentation décrira, dans une premiÚre partie, les caractéristiques de ce produit
cartographique, de sa méthode de production et de sa qualité statistique. Dans une seconde partie, la question
de lâincertitude spatiale de cette carte dâoccupation du sol sera abordĂ©e. Une comparaison avec un jeu de
donnĂ©es dâoccupation du sol digitalisĂ© manuellement sera prĂ©sentĂ©e au travers dâune modĂ©lisation spatialisĂ©e
espĂšce-habitat fondĂ©e sur la surface, lâhĂ©tĂ©rogĂ©nĂ©itĂ© et la connectivitĂ© forestiĂšre dâun paysage agricole pour
expliquer la richesse spĂ©cifique de syrphes (ordre des mouches) (Herrault et al., 2016). Les rĂ©sultats tendent Ă
montrer un effet nĂ©gligeable de lâincertitude spatiale sur les performances du modĂšle alors quâen parallĂšle le
recours Ă la cartographie par tĂ©lĂ©dĂ©tection de lâoccupation du sol permet dâenvisager une analyse plus
systĂ©matique de lâeffet de la matrice paysagĂšre dans son ensemble sur la biodiversitĂ©
Ătude du potentiel des donnĂ©es hyperspectrales en vue de dĂ©velopper une mĂ©thode de cartographie automatique du patrimoine arborĂ© en milieu urbain
Ătude du potentiel des donnĂ©es hyperspectrales en vue de dĂ©velopper une mĂ©thode de cartographie automatique
du patrimoine arboré en milieu urbain
Assessing land cover changes in the French Pyrenees since the 1940s A semiâautomatic GEOBIA approach using aerial photographs
International audienceAgro-pastoral landscapes of the Pyrenees are subject to fast spontaneous reforestation. The objective of this work is to assess the spatial patterns of land cover changes during the last 70 years in three study sites of the Pyrenees, and to compare the local dynamics in order to observe and to explain similarities and disparities
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