Aim To test whether it is possible to establish a common biogeographical regionalization for plants and vertebrates in sub-Saharan Africa (the Afrotropical Region), using objective multivariate methods.Location Sub-Saharan Africa (Afrotropical Region).Methods We used 1°grid cell resolution databases for birds, mammals, amphibians and snakes (4142 vertebrate species) and c. 13% of the plants (5881 species) from the Afrotropical Region. These databases were analysed using cluster analysis techniques to define biogeographical regions. A b(sim) dissimilarity matrix was subjected to a hierarchical classification using the unweighted pair-group method with arithmetic averages (UPGMA). The five group-specific biogeographical regionalizations were compared against a regionalization developed from a combined database, and a regionalization that is maximally congruent with the five group-specific datasets was determined using a consensus classification. The regionalizations were interpreted against measures of spatial turnover in richness and composition for the five datasets as well as the combined dataset.Results We demonstrate the existence of seven well-defined and consistent biogeographical regions in sub-Saharan Africa. These regionalizations are statistically defined and robust between groups, with minor taxon-specific biogeographical variation. The proposed biogeographical regions are: Congolian, Zambezian, Southern African, Sudanian, Somalian, Ethiopian and Saharan. East Africa, the West African coast, and the transitions between the Congolian, Sudanian and Zambezian regions are unassigned. The Cape area in South Africa, Afromontane areas and the coastal region of East Africa do not emerge as distinct regions but are characterized by high neighbourhood heterogeneity, rapid turnover of species and high levels of narrow endemism.Main conclusions Species distribution data and modern cluster analysis techniques can be used to define biogeographical regions in Africa that reflect the patterns found in both vertebrates and plants. The consensus of the regionalizations between different taxonomic groups is high. These regions are broadly similar to those proposed using expert opinion approaches. Some previously proposed transitional zones are not recognized in this classification.

Although satellite-based variables have for long been expected to be key components to a unified and global biodiversity monitoring strategy, a definitive and agreed list of these variables still remains elusive. The growth of interest in biodiversity variables observable from space has been partly underpinned by the development of the essential biodiversity variable (EBV) framework by the Group on Earth Observations -Biodiversity Observation Network, which itself was guided by the process of identifying essential climate variables. This contribution aims to advance the development of a global biodiversity monitoring strategy by updating the previously published definition of EBV, providing a definition of satellite remote sensing (SRS) EBVs and introducing a set of principles that are believed to be necessary if ecologists and space agencies are to agree on a list of EBVs that can be routinely monitored from space. Progress toward the identification of SRS-EBVs will require a clear understanding of what makes a biodiversity variable essential, as well as agreement on who the users of the SRS-EBVs are. Technological and algorithmic developments are rapidly expanding the set of opportunities for SRS in monitoring biodiversity, and so the list of SRS-EBVs is likely to evolve over time. This means that a clear and common platform for data providers, ecologists, environmental managers, policy makers and remote sensing experts to interact and share ideas needs to be identified to support long-term coordinated actions.

AimWe analyse the geographical distribution of 1911 Afrotropical bird species using indices of three simple biogeographic patterns. The first index, the frequency of species with range edges (T e ), is formulated to map directly the density of species distribution limits, for comparison with the results of traditional biogeographical classification and ordination procedures, in order to show variations in the strength and breadth of transition zones. The other two indices are formulated to seek to distinguish as directly as possible between two components within these transition-zone patterns: contributions from gradients in species richness (T g ); and contributions from replacements among species (T r ). We test the ability of these indices to discover the same boundaries among Afrotropical bird faunas as one popular procedure for classifying areas (TWINSPAN) and then use them to look for geographical trends in the different kinds of transition zones.Location The analysis is restricted to the sub-Saharan or Afrotropical region, excluding the Arabian Peninsula, Madagascar and all offshore islands. MethodsWe record the presence of each species in 1961 1°×1°grid cells of the map. To apply the three indices, each (core) grid cell in turn is compared with its neighbouring eight cells in the grid. The range edges index (T e ) counts the number of species with range edges between the core cell and the surrounding cells. The richness gradients index (T g ) counts the largest difference in species richness measured diametrically across the core cell in any direction when there is a consistent trend in richness along this line of three cells. The species replacements index (T r ) counts the number of species pairs recorded within a nine-cell neighbourhood that are not corecorded within any of the cells. Values for each of the 1961 grid cells are calculated and used to produce colour-scale maps of transition zones.Results Large-scale spatial patterns of variation in density of range edges (T e ) are consistent with classifications of the same data and with most previous biogeographical classifications proposed for the region. Variation in richness gradients (T g ) and species replacements (T r ) explain different parts of this pattern, with transition zones around humid forests in the equatorial region being dominated by species replacement, and transition zones around deserts (most extensive in the north and south) being dominated by richness gradients. Main conclusionsThe three indices distinguish the spatial arrangement and intensity of different kinds of transition zones, thereby providing a first step towards a more rigorous mechanistic understanding of the different processes by which they may have arisen and are maintained. As an example of one such pattern shown by our analyses of Afrotropical birds, there is evidence for a broad latitudinal trend in the nature of transition zones in faunal composition (following the latitudinal distribution of the different kinds of habitat transitions), from being dominated by s...

Summary 1.Fire is an important process in Mediterranean-ecosystem shrublands, and prescribed burning is often used to manage these ecosystems. Analyses of past fire regimes are required to interpret biotic responses to fire, as well as to assess the degree to which management interventions have been able to influence the fire regime. 2. We used a spatial data base of fires within 10 protected areas covering >720 000 ha to examine the frequency, seasonality, size and cause of fires over four decades. Our study covered five fire climate zones and a range of mountain fynbos shrubland types. We examined whether regular prescribed burning would be necessary to rejuvenate the vegetation, and also to reduce the incidence and extent of wildfires. 3. Cumulative fire frequency distributions indicated that the probability of fire was not strongly affected by post-fire age, with 50% of the area experiencing a successive fire within 10-13 years after the previous fire in most areas. This suggests that the accumulation of fuel did not limit the occurrence of wildfires, and that regular prescribed burning would not necessarily reduce the risk of wildfires. 4. Inland zones experienced more severe fire weather than coastal zones (35% vs. 11-19% of days with high to very high fire danger, respectively). Despite these differences, fire return periods were similar (10-13 years), suggesting that the availability of ignitions, and not fuel or weather, limited the occurrence of wildfires. 5. Despite a policy that promoted prescribed burning, a relatively small area (between 4AE6% and 32AE4% of the area of all fires) burned in prescribed burns. Seasonal restrictions for safety and ecological reasons, the imperative to integrate planned fires with invasive alien plant treatments and unplanned wildfires have all contributed to the relatively small area that burnt in prescribed burns. 6. Synthesis and applications. Recurrent wildfires, and not prescribed burning, are providing sufficient opportunities for fire-stimulated regeneration in fynbos ecosystems. Because of this, and because burning to reduce fuel loads is unlikely to prevent wildfires, there should be less pressure to conduct prescribed burning. The predicted growth in human populations in all areas is expected to increase the number of ignition opportunities and the frequency of fires, with detrimental consequences for biodiversity conservation and the control of invasive alien trees. Fire frequency should thus be monitored and steps should be taken to protect areas that burn too frequently.

Abstract.Biogeographical zones are described for terrestrial bird species endemic to the Afrotropics using up-to-date distributional data and multivariate statistical techniques. This provides an objective basis for a hierarchy of subregions, provinces and districts, based on a set of rules. Results are compared to previous studies at continental and regional scales. Biogeographical zones for passerines and non-passerines are compared and found to be similar. Peaks of species richness and narrow endemism are described for the six major subdivisions (subregions) identified by the cluster analysis. Coincidence of peaks of species richness and narrow endemism is found to be low, such that areas selected to represent high species richness tallies will often fail to represent narrow endemics. Strong regionalization of Afrotropical birds indicates the need to use a biogeographical framework in conservation priority setting exercises to ensure that unique, but species-poor, avifaunas are not neglected.

In this study we combined an extensive database of observed wildfires with high-resolution meteorological data to build a novel spatially and temporally varying survival model to analyze fire regimes in the Mediterranean ecosystem in the Cape Floristic Region of South Africa (CFR) during the period 1980-2000. The model revealed an important influence of seasonally anomalous weather on fire probability, with increased probability of fire in seasons that are warmer and drier than average. In addition to these local-scale influences, the Antarctic Ocean Oscillation (AAO) was identified as an important large scale influence or teleconnection to global circulation patterns. Fire probability increased in seasons during positive AAO phases, when the subtropical jet moves northward and low level moisture transport decreases. These results confirm that fire occurrence in the CFR is strongly affected by climatic variability at both local and global scales, and thus likely to respond sensitively to future climate change.Comparison of the modeled fire probability between two periods (1951-1975 and 1976-2000) revealed a four year decrease in an average fire return time. If, as currently forecasted, climate change in the region continues to produce higher temperatures, more frequent heat waves, and/or lower rainfall, our model thus indicates that fire frequency is likely to increase substantially. The regional implications of shorter fire return times include shifting community structure and composition, favoring species that tolerate more frequent fires.Keywords: Fire regime, Cape Floristic Region, Mediterranean, fynbos, climate change, hierarchical Bayesian 3 IntroductionOver half of the world's terrestrial ecosystems are dependent on fire to maintain ecological structure and function (Shlisky et al. 2007). Fire regimes in these regions have a profound ecological role (Bond 1995) that can be strongly influenced by weather and climate (McKenzie et al. 2004). Thus in addition to the direct physiological impacts of changes in temperature, precipitation, and CO 2 concentration due to climate change, changes in the fire regime will have potentially major effects on these fire-driven ecosystems (Bond et al. 2003). Since the 1980s there has been speculation about the impact of climate change on wildfire regimes (Balling et al. 1992;Clark 1988;Layser 1980), and some studies have produced evidence of changes in fire regimes associated with recent climate change (Gillett et al. 2004;Westerling et al. 2006).However, most of this work has been limited to North America, Europe, and Australia, and much uncertainty remains regarding the sensitivity of wildfire to weather trends and variability in many other fire-prone regions of the world. In this study we present a novel model for fire return times that allows integration of decades of regional-scale weather data at high spatial and temporal resolution, while retaining the temporal dependence structure of a fire survival model.We apply this model to some of the richest fire oc...

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Geographical patterns and peaks of species richness and narrow endemism (defined by rangerestrictedness and range-size rarity) are described for terrestrial Afrotropical birds and subsets thereof based on residency, endemism, and taxonomy. Species richness for residents and Afrotropical endemics (species globally restricted to sub-Saharan Africa) peaks along the mountains and adjacent lowlands of eastern and southern Africa. Isolated mountains in central and western Africa and the lowlands of the north-eastern Congo Basin (Ituri) are highlighted to a lesser degree. Peaks of narrow endemism occur in these areas as well as in the Ethiopian Highlands (particularly for non-passerines), Somalia (particularly for passerines), and the Angolan Escarpment. Within residents, patterns of species richness vary greatly between Afrotropical endemics (which concentrate in forests on mountains and adjacent lowlands, and the southern Brachystegia woodlands) and non-endemic residents (which concentrate in Sudanian woodlands and the Ethiopian Highlands). Patterns of species richness of residents (species that breed in the Afrotropics) and non-breeding migrants (non-breeding visitors to the Afrotropics) also show notable differences. The latter concentrate in areas close to the Palaearctic, which forms their distributional range centres. Patterns of species richness and narrow endemism for Afrotropical endemics show broad-scale coincidence within mountains or mountain-lowland complexes, particularly the Cameroon-Bamenda Highland system, East African rift system and Eastern Arc mountains.However, fine-scale coincidence of peaks of species richness and narrow endemism within these complexes is low. Narrow endemism peaks occur in areas of topographical complexity, which may have conferred localized climatic stability over short-, medium-, and long-term climatic cycles (sensu Fjeldsa , 1994; Fjeldsa et al., 1997), allowing these areas to act as `species pumps'. Species accumulate in areas of high productivity. Lack of fine-scale coincidence of narrow endemism and species richness peaks have implications for conservation prioritization exercises.