Extinctions are often the result of multiple factors that are difficult to disentangle and so methods for identifying simple and combined types of extinctions are valuable for both basic and applied ecology. We applied a modification of variance partitioning and a hierarchical partitioning analysis to test several hypotheses that attempt to explain the recent large-scale disappearance of Egyptian Vulture breeding territories in Spain. Our aim was to identify and then separate the simple (or pure) from the combined effects of habitat features, human pressure, and the social behavior of the species on the risk of extinction from a territory while controlling for spatial autocorrelation. Deviance partitioning showed that a complex mix of factors is significantly related to the disappearance of more than 400 territories throughout Spain. Abandoned territories were located in areas that are isolated from other conspecific territories and far from communal roost sites. In addition, these territories were found in places where there is a lack of natural habitats, high habitat fragmentation and reduced habitat diversity, and where food availability seems to be low and the illegal use of poison to control predators is a common practice. Deviance partitioning also showed an important spatial component in the probability of extinction. Abandoned territories were not randomly distributed; rather, they were aggregated in extinction 'hotspots', mainly related to food availability and human pressure. Deviance partitioning turned out to be an useful tool for identifying the relative contribution of a variety of factors -and their combined effects -associated with an extinction process.The deviance explained by each factor must be interpreted, however, in the context of a good knowledge of the life history of the species. Hierarchical partitioning can help rank conservation priorities and, by using as an objective criterion the relative weight of each independent variable that could be effectively managed for conservation, may provide wildlife managers with a means of saving funds and optimizing action plans.

A vegetation cover increase has been identified at global scales using satellite images and vegetation indices. This fact is usually explained by global climatic change processes such as CO(2) and temperature increases. Nevertheless, although these causes can be important, the role of socioeconomic transformations must be considered in some places, since in several areas of Northern Hemisphere an important change in management practices has been detected. Rural depopulation and land abandonment have reactivated the natural vegetation regeneration processes. This work analyses the vegetation evolution in the central Spanish Pyrenees from 1982 to 2000. The analysis has been done by using calibrated-NDVI temporal series from NOAA-AVHRR images. A positive and significant trend in NDVI data has been identified from 1982 to 2000 coinciding with a temperature increase in the study area. However, the spatial differences in magnitude and the sign of NDVI trends are significant. The role of land management changes in the 20th century is considered as a hypothesis to explain the spatial differences in NDVI trends. The role of land-cover and human land-uses on this process has been analyzed. The highest increment of NDVI is detected in lands affected by abandonment and human extensification. The importance of management changes in vegetation growth is discussed, and we indicate that although climate has great importance in vegetal evolution, land-management changes can not be neglected in our study area.

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This paper analyses the role of climatic aridity on the spatial differences of vegetation activity and its inter-annual variability in a semi-arid region of the North East of the Iberian Peninsula. The vegetation activity was quantified by means of a monthly Normalized Difference Vegetation Index (NDVI) database from NOAA-AVHRR satellite images (1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000) at 1 km 2 of spatial resolution. Coefficients of variation (CoV) from temporal NDVI series were also calculated. The greater temporal variability of NDVI was recorded in areas with low vegetation cover (steppe and dry farming lands), whereas the lowest temporal variability of NDVI was recorded in the irrigated lands and forests located in the most humid areas. There is a strong and negative relationship between the CoV and the NDVI distribution, but we recorded important differences among land uses. Using maps of annual precipitation and temperature obtained by means of a regression-based method, we studied the influence of aridity on spatial patterns of NDVI and CoV values. The results show the high influence of aridity on the spatial distribution of vegetation activity in the Middle Ebro Valley. Aridity causes a general decrease of NDVI and an increase of CoV. Nevertheless, non-linear ARTICLE IN PRESS www.elsevier.com/locate/jnlabr/yjare 0140-1963/$ -see front matter r (S.M. Vicente-Serrano).relationships between aridity and NDVI and CoV were recorded for the whole of the study area and for the different land uses. The relationships between aridity and vegetation patterns in the semi-arid region studied are discussed in depth. r

[1] Detection and parameterization of forest fires is a task traditionally performed by polar-orbiting sensors, mainly advanced very high resolution radiometer (AVHRR) advanced along track scanning radiometer (AATSR), bispectral infrared detection (BIRD), and Moderate Resolution Imaging Spectroradiometer (MODIS). However, their time resolution is a problem to operate in real time. New geostationary sensors have proven their capacity for Earth observation. GOES, MSG, and MTSAT are already operative with time resolutions below 30 min. The international community feels that a real-time global observation network may become a reality, which is the aim of the Global Observations of Forest Cover and Land Cover Dynamics (GOFC/GOLD) FIRE Mapping and Monitoring program, focusing internationally on decision-making concerning research into global change. This paper shows the operation in real time by the MSG SEVIRI sensor over the Iberian Peninsula. For fire detection, a temporal gradient of temperature 3.9 mm is used, which is more efficient at eliminating incoming false alarms from solar reflection. Capacity to detect hot forest fires below 0.3 ha in Mediterranean latitudes has been analyzed along with the conditions in which it is possible to apply the MODIS methodology to establish the fire radiative energy (FRE) by means of experimental relation. We found that in this case, fire size can introduce maximum differences of 40% in FRE for small-scale fires. The capacity of this sensor is shown in different cases that have greatly impacted Spain and Portugal because of the loss of human life.