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The north western Atlas Mountains (Béchar region) act as refugia for relict populations of many species which highlights their interest as priority areas for conservation. Further work since the beginning of the last century has been difficult because of restricted access in a military area with long-standing border conflicts. This paper aims to analyse the temporal dynamics of the vegetation communities, to assess the floristic diversity of one of those isolated djebels, Djebel Antar, and to contribute to the knowledge of the conservation status of the species found. Surveys from 1925,1951 (published data) and 2017 (fieldwork) were interpreted and investigations were carried out on honey harvesting, production, and marketing in the Benzireg area to better understand and contribute to the development of beekeeping. A high proportion of endemic and very rare species was found. A tendency towards the homogenisation of the flora was detected with a decrease in plant diversity. Beekeeping is being tested as a means of enhancing biodiversity and contributing to the fight against vegetation degradation by reducing pastoral pressure. Djebel Antar retains its function as a refuge for biodiversity and may play an important role in conservation measures. [ABSTRACT FROM AUTHOR]

Northwestern Morocco is characterized by highly anthropized landscapes under the combined effect of agricultural intensification, resource overexploitation, urbanization, and tourism, but also local reforestation. Reconstructing the recent changes in vegetation in the region of the lower valley of the Loukkos river near Larache and their relationship to the settlement history are particularly helpful for understanding the processes at work within the landscape construction. The geohistorical approach combines paleoenvironmental, documentary, and historical data. The last few centuries have seen the emergence of wooded stands, in which cork oaks are a structural element. As forests were retreating, parklands intended for agriculture, agroforestry, and herding, like the Spanish dehesa and Portuguese montado, began to emerge. Nearly all of them have disappeared today, but we can identify their legacy and evaluate their cultural significance through comparing them with their counterparts in the Iberian Peninsula, but also in other areas of Morocco. Their deep historical roots give this landscape an evolving heritage character that is directly linked to the communities' lifestyles, culture, and history. [ABSTRACT FROM AUTHOR]

The island of Madagascar, located in the southern hemisphere between the equator and the Tropic of Capricorn in the Indian Ocean, 450 km from the African continent, is particularly affected by wildfires. The vegetation of the phytogeographic Western Domain of the island consists largely of savannas, wooded grassland, and secondary grassland, maintained by the repeated action of fire operating each year on a seasonal cycle. Rural populations employ fire to manage land use. Depending on the burning practice and the environment in which the fires happen, the impacts vary. This paper supplement the studies that have so far located and quantified wildfires by taking into account their different behaviors, particularly their spread. We analyzed the modalities of the relationship between the two fire products, active fire and burned area, derived from Moderate Resolution Imaging Spectroradiometer (MODIS) data to establish a typology based on fire spread patterns. We identified three general patterns of fire behaviors, as well as their locations in the studied area. Spatial analysis of this patterns enabled us to understand spatial logics better. Type 1 fires are the least frequently observed and have many active fires, but little or no burned area. Type 2 fires are the most common and have areas that burn like a mosaic. Type 3 fires are observed slightly less frequently than the previous type and have few active fires and large burned areas. An inter-annual analysis reveals the spatial stability or variability of these fire types. [ABSTRACT FROM AUTHOR]

We introduce here the term “River Culture” to delineate an eco-social approach to mitigate the biological and cultural diversity crisis in riverscapes. It is based on the insight that current environmental change endangers both, biological and cultural diversities in rivers and their basins, and those activities to improve ecosystem functions, biodiversity and capacity of the biological species to evolve will have a similarly positive effect on human cultural diversity. “River Culture” has two dimensions, including (a) the influence of the biophysical setting of rivers (specifically, their pulsating flow regimes and their biological features) on the expression of elements of human culture in general and (b) the aspect of “learning from the river” for the development of technologies and management options that are targeted to maintain and improve ecosystem functions and diversity in a more sustainable way. The River Culture approach, as given in this concept and discussion paper, is preliminarily based on five tenets: (1) Reset values and priorities in riverscape management in favor of human wellbeing and a harmonious coexistence of man and riverscape; (2) Live in the rhythm of the waters, i.e. adapt management options in accordance with the hydrological dynamics rather than fighting against them; (3) Transform traditional use of rivers into modern cultural activities and management options; (4) ‘Ecosystem bionics’: by copying survival strategies of flood-pulse adapted organisms novel forms of human use can be developed; (5) Make the catchment (river basin) the geographical base unit for all kinds of political decisions in landscape management. [ABSTRACT FROM AUTHOR]

In Sudanian savannas, frequent fires are required to maintain a mix of trees and grasses. After a century of long conflict over fire utilisation and resource management, arising from colonial scientists reacting against traditional practice, fire has become a management tool used to shape tropical vegetation. Many examples show that fire is allowed and used in protected areas, and more recently, tolerated in West African countrysides. If fires are no longer viewed as 'evil' for African landscapes, fire setting remains a problem. Nowadays, fire ecology and the savanna concept focus on fire seasonal temporality, and create a new and more specific category of contested fires, or late-season fire, referred to in this paper as 'bad fires'. This specific category generally conceives fire as a biophysical element, which leads to savanna degradation. This paper examines the reality of 'bad fires' in the Western Burkina Faso through a space-time analysis to investigate the existence of an annually seasonal pattern of fires created by peasants. Using spatial association ( I_ Moran) on active fire MODIS products, we are able to demonstrate a deterministic regional pattern occurring over six years (from 2004 to 2009). Results of this study confirm the importance of a close study of fire in its temporal dimension with respect to temporality in burning practices. Conclusions show that the details of timing in fire-setting are key and also bring us new perspectives to understanding fire collective management at a local scale and new elements for climate modelling at a global scale. [ABSTRACT FROM AUTHOR]

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Biome reconstruction from pollen and plant macrofossil data provides an objective method to reconstruct past vegetation. Biomes for Africa and the Arabian peninsula have been mapped for 6000 years bp and provide a new standard for the evaluation of simulated palaeovegetation distributions. A test using modern pollen data shows the robustness of the biomization method, which is able to predict the major vegetation types with a high confidence level. The application of the procedure to the 6000 years data set (pollen and plant macrofossil analyses) shows systematic differences from the present that are consistent with the numerous previous regional and continental interpretations, while providing a more extensive and more objective basis for such interpretations. Madagascar, eastern, southern and central Africa show only minor changes in terms of biomes, compared to present. Major changes in biome distributions occur north of 15°N, with steppe in many low-elevation sites that are now desert, and temperate xerophytic woods/scrub and warm mixed forest in the Saharan mountains. These shifts in biome distributions imply significant changes in climate, especially precipitation, between 6000 years and present, reflecting a change in monsoon extent combined with a southward expansion of Mediterranean influence. [ABSTRACT FROM AUTHOR]

A pollen diagram from Oursi in Burkina Faso is compared with anthracological (charcoal analysis) results from three sites in northeast Nigeria (Konduga, Gajiganna, Lantewa). The present-day vegetation at all four sites is Sahelian or Sahelo-Sudanian and under heavy human impact. At Oursi, a closed grassland with only few trees and almost no Sudanian elements can be reconstructed for the middle Holocene. At the Nigerian sites, on the other hand, Sudanian woody plants were present during this period. We assume that the Sahel was not a uniform zone during the middle Holocene but rather a mosaic of different vegetation types according to local site conditions. In the light of these results, a simple model of latitudinally shifting vegetation zones is not applicable. Around 3000 B.P. the closed grassland at Oursi was opened by agro-pastoral activities, and at Gajiganna, plants characteristic of pasture lands can be directly related with the presence of cattle. Human impact seems to have been the dominant factor in the vegetation history of the Sahel from 3000 B.P. until today, masking possible effects of climatic change. [ABSTRACT FROM AUTHOR]

Since the end of the 1950s it has generally been accepted that, during the mid-Holocene humid period, the central Saharan mountain vegetation (Ahaggar, Tassili-n-Ajjer and Tibesti) was clearly Mediterranean or even forest in nature. In addition to the present-day elements growing in North Africa the flora was supposed to have included some European arboreal species. This concept was mainly based on the results of pollen analysis. More recent pollen and macrofossil analysis of organic sediments from the Ahaggar massif show that mid-Holocene flora was actually very similar to that found at the present day. Earlier studies had included analysis of sediment contaminated by pollen transported long distances which had accumulated over a period of 4000 years. An endemic olive (Olea laperrini) and the Atlas pistachio tree (Pistacia atlantica), two species which are still well represented nowadays, dominated the vegetation. The new data question the extension of the Mediterranean vegetation towards the south and the amplitude of the associated climatic change. [ABSTRACT FROM PUBLISHER]