225 research outputs found
Dynamique des Brûlis dans les Aires Protégées du Réseau SUN [Bénin, Burkina Faso, Niger et Sénégal] - Saison Sèche 2007-2008: Octobre 2007 - Mars 2008
Le CCR a effectué un suivi systématique des feux dans les 5 aires protégées du réseau SUN [forêt classées de Patako et de Boulon ; parcs nationaux du W-du-Bénin, W-du-Burkina et W-du-Niger] pendant la saison sèche 2007-2008, sur la base d¿images à moyenne résolution acquises par le capteur MODIS installé à bord des satellites Terra et Aqua. L¿élaboration de ces données a permis i)l¿inventaire hebdomadaire des épisodes de feu ; ii)la cartographie des surfaces brûlées, en moyenne deux fois par mois ; iii)l¿établissement d¿un Bulletin Hebdomadaire d¿Information sur les feux, à destination des membres du réseau et des équipes de gestion des aires protégées concernées. Par ailleurs il est montré comment le rapport entre la densité des feux [nombre de feux / 1000 ha] à l¿extérieur et à l¿intérieur d¿une aire protégée constitue un bon indicateur de différenciation de l¿aire par rapport à l¿espace environnant, en termes de disponibilité et d¿agencement spatial du combustible. C¿est une indication i) de la qualité de l¿habitat naturel dans l¿aire; ii) de son degré d¿isolement; iii) de son niveau de protection. Dénommé Indice de Spécificité dans ce document, ce rapport constitue un bon outil de suivi et de comparaison des aires protégées. Il a été utilisé pour comparer les situations observées dans les aires du réseau SUN avec celles prévalant dans les 33 autres parcs nationaux du domaine soudanien d¿Afrique sub-saharienne.JRC.DDG.H.3-Global environement monitorin
Dynamique des brûlis dans le Parc Régional du W, le Parc National de La Boucle de la Pendjari et la Réserve d¿Arly - Implications pour la gestion de ces aires protégées
Le parc régional transfrontalier du W (Bénin, Burkina Faso et Niger), d¿une superficie de 10,300 km2, fait partie du complexe écologique du WAP (30,000 km2). Le Parc du W est classé, depuis novembre 2002, réserve transfrontalière de la biosphère et bénéficie d¿un soutien technique et financier de l¿UE depuis janvier 2001 dans le cadre du programme Parc W ¿ ECOPAS. La maîtrise des brûlis est un aspect essentiel dans la gestion du parc. Le CCR a donc effectué un suivi satellitaire systématique des feux durant la saison sèche 2006-2007 ainsi qu¿une analyse rétrospective jusqu¿en janvier 2000. Ce document présente les caractéristiques essentielles de la saisonnalité des brûlis au sein du WAP ainsi que leur distribution spatiale. Cet ensemble d¿information est confronté au Plan d¿Aménagement et de Brûlis souhaité par les gestionnaires du Parc du W. Les conclusions de cette étude devraient aider à la mise en place du plan de brûlis et à son adaptation progressive pour mieux répondre aux objectifs d¿aménagement et de conservation du parc.JRC.H.3-Global environement monitorin
Fire Activity Inside and Outside Protected Areas in Sub-Saharan Africa: A Continental Analysis of Fire and its Implications for Biodiversity and Land Management
Fire is an important ecological factor in many natural ecosystems. Without doubt one of the biomes with the highest fire activity in the world is the African savannah. Savannahs have evolved with fires since climate in these regions is characterized by definite dry and wet seasons that create the conditions for burning. During the wet months the herbaceous vegetation shows a quick growth, followed by a long dry period during which the abundant build-up of fine materials becomes highly flammable and most of fires occur. Animals and plants are adapted to these conditions and their lives depend on recurrent fires. In this context fire becomes an essential element to promote biodiversity and nature conservation. Park managers are using programmed fires as a tool to maintain the habitats and favorable conditions to the animal communities.
Satellite products like burned areas and active fire maps are a valuable mean to analyze the fire activity and provide support to experts working for conservation and natural resource management.
In the framework of the Digital Observatory for Protected Areas (DOPA), the MONDE group (Monitoring Natural Resources for Development) of the Joint Research Centre of the European Commission is using satellite products to analyze the fire occurrence and its effects on protected areas located in sub-Saharan Africa. Information on the fire activity was derived from the MODIS fire products (active fires and burned areas) and allows the DOPA to provide support to park managers as well as to experts working for conservation and natural resource management.
We assessed 741 protected areas classified by the IUCN (International Union for Conservation of Nature) with a level of protection between class I and IV. The MODIS datasets are available since the year 2000 and were used to characterize the spatio-temporal distribution of fires over a period of 10 years. Information on fire activity was extracted for the protected areas and a 25km buffer zone around each of them. The region outside the protected areas was used for comparison in order to identify differences or similarities between their fire activities. This also contributed to understand how management and conservation influence fire and assess the level of isolation of the protected areas. The long time series allowed the identification of trends and the interannual variability in the fire activity.
The dry season length was determined using FEWS RFE rainfall data (implemented at NOAA's Climate Prediction Center). Within each dry season we identified three periods (early, middle and late) in order to characterize the climatic and environmental conditions at which fires occur and identify trends and patterns. Every period of the dry season lasts two months and shows different conditions of temperature and drought level.
Fire activity was characterized combining the information on active fires and burned areas. For each year we determined the fire seasonality, the fire frequency, the main vegetation types affected, the extent and intensity of burning.
This information was also used to distinguish management fires from those related to other human activities like transhumance, agriculture and poaching in order to identify possible sources of threat to the protected areas. Information on the road network, the location of villages and cultivated fields were also included.
Future work will include a combined analysis of fire activity and land-cover, land-cover change information so that management plans adopted in protected areas can be evaluated in their effectiveness to promote biodiversity and nature conservation.JRC.DDG.H.3-Global environement monitorin
The Assessment of African Protected Areas
In order to achieve goals for reduction in the rate of biodiversity loss, it is vital that geographically flexible conservation funding is focused on the areas where biodiversity is the highest and is most threatened. There is currently a shortage of systematic and repeatable methods for the assessment of priority areas for conservation. Furthermore, existing prioritisations tend to focus on large biogeographical units, defined by regional experts. We propose a continental scale repeatable methodology, using existing geographical databases, for the prioritisation of African protected areas. This information is utilised to develop 6 indicators for each protected area, quantifying its value with regards to amphibian, bird and mammal species diversity, irreplaceability of habitat, and threat from population pressure and agricultural boundary pressure. These indicators are then summarised to show how the protected area performs, for each indicator, in comparison to other protected areas from the same country or the same ecoregion. Results are also synthesised to show the most valuable protected areas for a given taxa. Finally, the prioritisation is presented via the internet in conjunction with phenology, climate, and environmental information specific to each protected area.JRC.H.3-Global environement monitorin
Caractérisation de la Dynamique des Feux et del'Evolution du Couvert dans le Parc du W Burkina Faso, Bénin et Niger.
Abstract not availableJRC.H-Institute for environment and sustainability (Ispra
Associations of biomechanical properties of the cornea with environmental and metabolic factors in an elderly population : the ALIENOR study
PURPOSE: The purpose of this study was to assess the associations of biomechanical properties of the cornea with metabolic and environmental factors in an elderly population. METHODS: The ALIENOR (Antioxydants, Lipides Essentiels, Nutrition, and Maladies OculaiRes) study is a population-based study. In 2009-2010, 624 subjects, aged 74 years or more, underwent an eye examination, including intraocular pressure (IOP), central corneal thickness (CCT), and biomechanical properties of the cornea measurements using the Ocular Response Analyzer. Socio-demographic, lifestyle, and medical history data were collected using standardized questionnaires. Mean lifetime ambient ultraviolet (UV) exposure was estimated using residential history and statistics of UV radiation at each location using the Eurosun UV database. RESULTS: Mean age was 82.2 ± 4.3 years. Mean corneal hysteresis (CH), corneal resistance factor (CRF), and CCT were 9.4 ± 1.9, 9.8 ± 1.9 mm Hg, and 551.6 ± 36.8 μm, respectively. In the multivariate analysis, CH and CRF values were significantly lower in subjects older than 80 years (-0.56; 95% confidence interval [CI]: -0.89;-0.24); P < 0.001 and -0.48; 95% CI: -0.75;-0.20; P < 0.001, respectively), in subjects having higher ambient UV exposure (-0.50; 95% CI: -0.88;-0.12; P < 0.01; and -0.46; 95% CI: -0.78;-0.13); P < 0.05, respectively), and in subjects with high plasma LDL cholesterol (CH: -0.46; 95% CI: -0.86;-0.03; P < 0.05; and CRF: -0.37; 95% CI: -0.72;-0.008; P < 0.05). Central corneal thickness was significantly higher in former smokers than in never smokers (+11.01; 95% CI: 0.48;21.55; P < 0.05) and was not significantly associated with age, ambient UV exposure, diabetes, or LDL cholesterol. CONCLUSIONS: Biomechanical properties of the cornea are modified by metabolic and lifetime environmental factors, especially UV exposure. The manner these factors may influence onset and progression of ocular diseases or IOP measurements need further investigation
ACP Fire Monitoring Tool for protected area management
This report documents the context and the objectives of a new Fire Monitoring Tool developed in the framework of the JRC activity in African, Caribbean and Pacific (ACP) Countries.
Vegetation fires are widespread in Africa and are a key component of many ecosystems. They can be a cause of threat and damage for ecosystems not adapted to them, but for many African habi-tats fires are just as important as rain. As a consequence of this, dedicated fire programs are often included in the protected areas conservation plans to maintain or improve the ecosystem structure and the landscape diversity that are essential to biodiversity. Information on fire activity becomes therefore critical for the implementation of conservation programs and the man-agement of protected areas.
With the support of Earth Observation (EO), fire monitoring is possible, at global level, over long time periods. However, EO products require technological know-how which is often limited for many ecologists and park managers.
In this study we present a new tool for fire monitoring that we developed especially for people working in conservation and park management. The tool is a web client that provides historical and near-real time indicators of the fire activity derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) burned area and active fire products. The MODIS products are dis-tributed by NASA-FIRMS and the University of Maryland and cover more than a decade going from late 2000 to present.
The web client is available on-line and produces, on the fly, graphs, tables and maps of the fire activity, for a selected protected area and period of time. The content and its graphical represen-tation have been designed to provide a synthesis of the fire activity with no need of additional softwares to visualize or use the data.JRC.H.5-Land Resources Managemen
15K thermal buffer using liquid hydrogen
This work is supported by the European Space Agency (ESTEC contract 4000108532/12/NL/E and by Fundação para a Ciência e Tecnologia (PTDC/EMEMFE/101448/2008 and PEst-OE/FIS/UI0068/2011). PBS and DM acknowledge the latter institution for granting.authorsversionpublishe
Two-cross-polarized-frequency VECSEL at 852nm for CPT-based Cs clocks (poster)
International audienceWe demonstrate a tunable high-purity microwave signal generation from a cross- polarized dual-frequency diode-pumped vertical external-cavity semiconductor laser operating at 852 nm for the coherent population trapping of cesium atoms in compact atomic frequency references
Invest Ophthalmol Vis Sci
Purpose: To analyze the association between skin autofluorescence (sAF), estimating tissue accumulation of advanced glycation end-products (AGEs), and open angle glaucoma (OAG) in an elderly population. Methods: The Antioxydants, Lipides Essentiels, Nutrition and maladies OculaiRes (ALIENOR) study is an on-going epidemiologic population-based study on age-related eye diseases. In 2009 to 2010, 624 subjects, aged 74 years or older, were recruited. All subjects underwent a complete eye examination, including optic disc color photography and spectral-domain optical coherence tomography (SD-OCT) examination. Sociodemographic and medical history data were collected using standardized questionnaires. Glaucoma diagnosis was made using optic nerve head retinophotography and International Society for Epidemiologic and Geographical Ophthalmology criteria. sAF was measured with a noninvasive autofluorescence reader in 467 subjects. Results: Of subjects, 455 had complete data, 424 were classified as controls, and 31 classified as OAG. Mean age was 82.3 +/- 4.3 years, mean and median sAF were 2.8 +/- 0.7 and 2.7 arbitrary units (AU), respectively. In a multivariate analysis, higher sAF values (>/=2.7 AU) were associated with OAG (odds ratio [OR] = 2.28, 95% Confidence Interval [CI]: 1.03; 5.04). Other variables significantly associated with OAG were age (OR = 1.10, 95%CI: 1.00; 1.21), glaucoma family history (OR = 2.83, 95%CI: 1.14; 7.01) and smoking (1-20 pack-years [OR = 3.31, 95%CI: 1.18; 9.26]; >/=20 pack-years [OR = 3.85, 95%CI: 1.42; 10.46]). Conclusions: Higher level of sAF, which may act as a long-term biomarker of metabolic memory, and smoking are independently associated with an increased risk of glaucoma. Long-term accumulation of AGEs, a marker of oxidative stress, could play a role in the pathogenesis of glaucomatous chronic optic neuropathy
- …