Land system science and sustainable development of the earth system: A global land project perspective

Land systems are the result of human interactions with the natural environment. Understanding the drivers, state, trends and impacts of different land systems on social and natural processes helps to reveal how changes in the land system affect the functioning of the socio-ecological system as a whole and the tradeoff these changes may represent. The Global Land Project has led advances by synthesizing land systems research across different scales and providing concepts to further understand the feedbacks between social-and environmental systems, between urban and rural environments and between distant world regions. Land system science has moved from a focus on observation of change and understanding the drivers of these changes to a focus on using this understanding to design sustainable transformations through stakeholder engagement and through the concept of land governance. As land use can be seen as the largest geo-engineering project in which mankind has engaged, land system science can act as a platform for integration of insights from different disciplines and for translation of knowledge into action

An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples.

MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed.  Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination

Pf7: an open dataset of Plasmodium falciparum genome variation in 20,000 worldwide samples

We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network.  It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented.  For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations.  We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent.  We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines.  Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website

Food preferences and foraging strategies of wood-feeding termites in a West African savanna

The feeding preferences of termites in a Guinean savanna (Lamto, Côte d'Ivoire) were studied in the field to better understand the incidence of termite damages observed on adult trees, which, on interaction with fire, affect the dynamics of the tree community. Two separate multiple-choice test experiments were conducted on the six dominant tree species, aiming at determining preferences for the species and for wood conditions naturally encountered and likely to affect termite consumption behaviour. The preferences of termites were determined by their occurrence on standard-sized wood pieces and their behaviour during the first attack. Two fungus-growing termites, Ancis-trotermes and Microtermes were frequently encountered on wood pieces, whereas wood feeders were absent. The two genera have different preferences, and they do not compete for the same food. Wood density and water content did not explain termite preference. Holes in the bark seem to facilitate termite entry into pieces of wood, whereas the action of fire on wood apparently makes it less attractive to termites. In the field, the decision by termites to forage on a given tree species seems to be more driven by habitat and accessibility differences than real food quality differences

Atlas de la Biodiversité de l'Afrique de l'Ouest, Tome III: Côte d'Ivoire = Biodiversity Atlas of West Africa, Volume III: Côte d'Ivoire

La biodiversité comprend la plénitude de la vie dans toutes ses formes. Sa protection et son usage durable doivent ainsi être une partie intégrante d’une politique orientée vers l’avenir et ancrer de plus en plus dans la conscience politique et publique. La condition préalable pour cela est une meilleure compréhension des effets des actions humaines sur la biodiversité et une connaissance plus approfondie de sa valeur. La recherche scientifique contribue de façon indispensable à la préservation des biomes, des espèces et gènes. Elle ne se limite pas à fournir les connaissances fondamentales qui sont nécessaires pour arrêter le progrès de la disparition de la biodiversité. Bien plus, ce sont les chercheurs eux-mêmes qui, ensemble avec leurs partenaires locaux, élaborent des stratégies pour un usage durable de la biodiversité. Explorer la flore et la faune du continent africain, et mesurer les changements observés dans leur milieu naturel afin de les réduire, tels sont les objectifs de BIOTA (Biodiversity Monitoring Transect Analysis in Africa / Transect d´Analyse du suivi de la Biodiversité en Afrique de l´Ouest). Ce réseau de recherche a été créé en 1999 ensemble par les chercheurs africains et allemands. Vu la grande importance de BIOTA, cette initiative est non seulement financée par le Ministère fédérale de l’Education et de la Recherche, mais entre-temps aussi par plusieurs Etats africains et institutions partenaires. «BIOTA Ouest» a été lancé au début de 2001. Parmi les résultats de cette coopération réussie figurent le centre de biodiversité à Ouagadougou (Burkina Faso) et l’Atlas «BIOTA Ouest» actuel. Je me réjouis de l’apparition de cet atlas, qui constitue une vue d’ensemble compréhensive aussi bien que compréhensible des nombreux résultats de recherche et recommandations pratiques, car la biodiversité est une condition essentielle pour le fonctionnement de l’écosystème et, partant, le fondement de la vie humaine et de l’activité économique.Biodiversity encompasses the abundance of life in all its forms. Therefore, its protection and sustainable use have to be an integral part of future-oriented politics and must increasingly be incorporated in political and public awareness. The prerequisite for this is a better understanding of the effects of human actions on biological diversity and a more accurate knowledge of its value. Science and research contribute an indispensable share to the preservation of the diversity of habitats, species and genes. Not only does research provide the necessary basis of knowledge to prevent the ongoing loss of biodiversity. But it is the researchers themselves, who, at the same time develop strategies for the sustainable use of biological diversity, together with their local partners. To explore the flora and fauna of the African continent and to assess and mitigate changes in these regions is the challenge of BIOTA (Biodiversity Monitoring Transect Analysis in Africa). This research network was launched in 1999by African and German scientists. Due to the high relevance of BIOTA, the Federal Ministry of Education and Research (BMBF), along with several African states and partner institutions, are jointly sponsoring this initiative. “BIOTA West” was launched in the beginning of 2001. Apart from the Biodiversity Centre in Ouagadougou (Burkina Faso), the “BIOTA West”-Atlas, as presented here, is a result of this successful collaboration. I am pleased, that with this Atlas a comprehensive and at the same time generally understandable overview of the numerous research results and recommendations can be presented. Biodiversity is an indispensable prerequisite for the functioning of ecosystems and, hence, the foundation for human livelihood and economic activities

Lenticular mounds in the African savannahs can originate from ancient Macrotermes mounds

Small lenticular soil mounds are scattered in several African savannahs. At Lamto, Côte d’Ivoire, most of these lenticular mounds house nests of Odontotermes aff. pauperans which have to date been thought to have built them. However, repeated observations made in 2000 and 2015 supply several arguments in favour of another hypothesis, namely that after a nest of Macrotermes has been abandoned and eroded, it could be colonized by O. aff. pauperans and subsequently maintained, stabilized, by this latter species or possibly recolonized by another Macrotermes society.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Data from: Short-term changes in the structure of termite assemblages associated with slash-and-burn agriculture in Côte d'Ivoire

Termites are major decomposers in tropical regions and play critical roles in many soil-related processes. Studies conducted in Asia and the Neotropics suggest that habitat modification can strongly affect termite assemblages, but data on termite communities from forests in Africa, especially West Africa, are scarce. Here, we measured the short-term impact of slash-and-burn agriculture on termite assemblages in an agricultural region of central Côte d'Ivoire. We assessed termite diversity and relative abundance in four habitat types: secondary forest, cleared forest, burned forest, and crop fields. The secondary forest had higher species richness compared with the other habitats, but all habitat types had similar assemblage structures. Fungus-growing termites were the most abundant feeding group in all habitats. Soil feeders were most abundant in secondary forest, intermediately abundant in cleared and burned forests, and almost entirely absent in crop fields. Wood-feeding species showed clear responses to burning; their abundances decreased after fire. We conclude that slash-and-burn agriculture does not appear to severely erode the diversity of termite assemblages. This could be due to the dominance of ecologically versatile fungus growers or to the relatively long time between clearing and burning. However, forest clearing negatively affects soil feeders, with the Apicotermitinae most affected by canopy loss

Determinants of Termite Assemblages’ Characteristics within Natural Habitats of a Sudano-Guinean Savanna (Comoe National Park, Côte d’Ivoire)

Termites are one of the major components of tropical ecosystems. However, the ecological and biological variables determining the structure of their communities within natural habitats are less documented in general and especially in the Comoe National Park, a Sudano-Guinean savanna zone located in the north-eastern part of Côte d’Ivoire (West Africa). Using a standardized method of belt transects, the structure of termite’s communities was estimated within habitats differing in the structure of their vegetation, soil characteristics, and the disturbance level caused by annual occurrences of bushfires. The effect of a set of environmental variables (habitat type, occurrence of annual bushfire, woody plant density, woody plant species richness, and soil physicochemical parameters) was tested on the habitat-specific recorded termite species. Sixty species of termites belonging to 19 genera, seven subfamilies and two families, namely Rhinotermitidae (Coptotermitinae and Rhinotermitinae) and Termitidae (Apicotermitinae, Cubitermitinae, Macrotermitinae, Nasutitermitinae, and Termitinae) were sampled. These species were assigned to the four feeding groups of termites: fungus growers (18 species), wood feeders (17 species), soil feeders (19 species) and the grass feeders (6 species). The highest diversity of termites was encountered in forest habitats, with 37 and 34, respectively, for the gallery forest and the forest island. Among savanna habitats, the woodland savanna was identified as the most diversified habitat with 32 recorded species, followed by the tree savanna (28 species) and the grassy savanna (17 species). The distribution of termite species and their respective feedings groups was determined by the habitat type and a set of environmental variables such as Woody Plant Diversity (WPD), Woody plant Families Diversity (WPFD), and Organic Carbon (OC). The annual Fire Occurrence (FO) was found to indirectly impact the characteristics of termite assemblages within natural habitats via their respective Herbaceous Species Richness (HSR) and Woody Plant Species Richness (WPSR). In summary, the spatial heterogeneity of the Comoe National Park, modeled by the uncontrolled annual bushfire, offers a diversified natural habitat with an important variety of termite-habitat-specific species, probably due to the food preference of these organisms and its relatively good conservation status

Allocation strategies of savanna and forest tree seedlings in response to fire and shading: outcomes of a field experiment

International audienceThe forest-savanna ecotone may be very sharp in fire-prone areas. Fire and competition for light play key roles in its maintenance, as forest and savanna tree seedlings are quickly excluded from the other ecosystem. We hypothesized a tradeoff between seedling traits linked to fire resistance and to competition for light to explain these exclusions. We compared growth-and survival-related traits of two savanna and two forest species in response to shading and fire in a field experiment. To interpret the results, we decomposed our broad hypothesis into elementary tradeoffs linked to three constraints, biomass allocation, plant architecture, and shade tolerance, that characterize both savanna and adjacent forest ecosystems. All seedlings reached similar biomasses, but forest seedlings grew taller. Savanna seedlings better survived fire after topkill and required ten times less biomass than forest seedlings to survive. Finally, only savanna seedlings responded to shading. Although results were consistent with the classification of our species as mostly adapted to shade tolerance, competition for light in the open, and fire tolerance, they raised new questions: how could savanna seedlings survive better with a 10-times lower biomass than forest seedlings? Is their shade intolerance sufficient to exclude them from forest understory

Mort précoce des nids du termite du genre Macrotermes dans la Réserve Scientifique de Lamto en Côte d’Ivoire : compétition interspécifique ou action de fourmis prédatrices ?

Objectifs: Les nids du termite du genre Macrotermes sont l’une des caractéristiques des écosystèmes africains en général et des écosystèmes de savanes en particulier. Toutefois, à l’intérieur de la Réserve Scientifique de Lamto, en Côte d’Ivoire, une mort précoce de ces nids est observée. A l’inverse, le constat d’une grande densité et d’une importante fréquence de rencontre de ces nids sont fait en dehors des limites de cette réserve. Cette étude avait pour objectif général de déterminer les causes de la mort précoce de ces nids dans la réserve de Lamto. Spécifiquement, il s’est agi de (i) évaluer l’abondance et la distribution des nids du genre Macrotermes de différents types d’écosystèmes dans et en dehors de la réserve de Lamto, (ii) identifier les causes de la mort précoce des nids de Macrotermes dans la réserve de Lamto.Méthodologie et résultats: Pour ce faire, un repérage de nids de Macrotermes dans différents types d’habitats, dans et en dehors de la réserve de Lamto. Ce repérage a été suivi de la caractérisation de chacun des nids observés. Dans chaque type d’habitat, le repérage et la caractérisation des nids ont été effectués dans trois parcelles de 150 m x 150 m préalablement établies. Les prédateurs et les compétiteurs potentiels des Macrotermes ont été inventoriés à l’aide de monolithes de types Tropical Soil Biology and Fertility (TSBF) établis à un et 10 m des nids.Conclusions et applications des résultats: Seules des nids de l’espèce Macrotermes bellicosus ont été rencontrés au cours de cette étude. Aucun nid de l’espèce M. subhyalinus n’a été observé durant la présente étude. Il est ressortit une variation significative de l’abondance et de la densité de nids abandonnés et vivants de M. bellicosus entre l’intérieur et l’extérieur de la réserve de Lamto d’une part mais également d’un habitat à un autre. En outre, un grand nombre de nids de grande taille a été recensé en dehors de la réserve et les nids abandonnés sont généralement de petites tailles (volumes) et plus nombreux dans la réserve de Lamto, suggérant leur mort précoce effective dans ce milieu. Plusieurs espèces de termites et de fourmis ont été collectées autour des nids abandonnés et vivants ; avec  toutefois, une grande diversité autour des nids abandonnés, suggérant également une corrélation entre leur présence et la mort précoce des nids de M. bellicosus. D’autres pistes telles que celles de la dépression de consanguinité et de la qualité du sol pourraient être explorées pour obtenir des explications complémentaires à cette mort précoce des nids.Mots clés: Termites, Fourmis, Macrotermes, Nid, Réserve de Lamto, Côte d’IvoireEnglish Title: Premature death of nests in the genus Macrotermes within the Lamto Scientific Reserve in Côte d’Ivoire: interspecific competition or action of predatory ants?English AbstractObjectives: Nests of the genus Macrotermes are one of the main characteristics of African ecosystems in general and savannah ones particularly. However, within the Lamto Scientific Reserve in Côte d'Ivoire, a premature death of these nests is observed. Conversely, the high density and frequency of encounters of these nests are observed outside the boundaries of this reserve. The overall objective of this study was to determine the causes of the premature death of these nests in the Lamto Reserve. Specifically, this involved (i) assessing the abundance and distribution of nests of Macrotermes in different habitat types within and outside the Lamto Reserve, (ii) identifying the potential causes of the premature death of Macrotermes nests in this Reserve.Methodology and Results: Nests of Macrotermes were spotted in different habitat types, both within and outside the Lamto Reserve, followed by their characterization. In each habitat type, nest spotting and characterization were carried out in three previously established plots of 150 m x 150 m. Potential predators and competitors of the genus Macrotermes were inventoried using Tropical Soil Biology and Fertility (TSBF) monoliths, established at a distance of one and 10 m from the nest.Conclusion and applications of results: Only nests of the species Macrotermes bellicosus were encountered during this study. Those of M. subhyalinus were not observed during this work. A significant variation in the abundance and density of abandoned and live nests of M. bellicosus was observed inside and outside the Lamto Reserve on one hand, but also from a habitat type to another. In addition, a high number of mature nests has been seen outside the reserve. Inside the reserve, early abandoned nests (small in size) were found in abundance, suggesting their effective premature death in this protected area. Furthermore, several species of termites and ants were collected around both the abandoned and live nests; however, with a high diversity and abundance around the abandoned ones, suggesting a correlation between their presence and the premature death of these nests. Other avenues such as inbreeding depression and soil quality might be explored to obtain additional explanations to this premature death of Macrotermes nests within the Lamto reserve.Keywords: Termites, Ants, Macrotermes, Nest, Lamto Reserve, Ivory Coas