TY  - JOUR
A1  - Stein, Katharina
A1  - Coulibaly, Drissa
A1  - Balima, Larba Hubert
A1  - Goetze, Dethardt
A1  - Linsenmair, Karl Eduard
A1  - Porembski, Stefan
A1  - Stenchly, Kathrin
A1  - Theodorou, Panagiotis
T1  - Plant-pollinator networks in savannas of Burkina Faso, West Africa
JF  - Diversity
N2  - West African savannas are severely threatened with intensified land use and increasing degradation. Bees are important for terrestrial biodiversity as they provide native plant species with pollination services. However, little information is available regarding their mutualistic interactions with woody plant species. In the first network study from sub-Saharan West Africa, we investigated the effects of land-use intensity and climatic seasonality on plant–bee communities and their interaction networks. In total, we recorded 5686 interactions between 53 flowering woody plant species and 100 bee species. Bee-species richness and the number of interactions were higher in the low compared to medium and high land-use intensity sites. Bee- and plant-species richness and the number of interactions were higher in the dry compared to the rainy season. Plant–bee visitation networks were not strongly affected by land-use intensity; however, climatic seasonality had a strong effect on network architecture. Null-model corrected connectance and nestedness were higher in the dry compared to the rainy season. In addition, network specialization and null-model corrected modularity were lower in the dry compared to the rainy season. Our results suggest that in our study region, seasonal effects on mutualistic network architecture are more pronounced compared to land-use change effects. Nonetheless, the decrease in bee-species richness and the number of plant–bee interactions with an increase in land-use intensity highlights the importance of savanna conservation for maintaining bee diversity and the concomitant provision of ecosystem services.
KW  - bees
KW  - community composition
KW  - connectance
KW  - land-use intensity
KW  - modularity
KW  - mutualism
KW  - number of interactions
KW  - seasonality
KW  - woody plant richness
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-220157
SN  - 1424-2818
VL  - 13
IS  - 1
ER  - 
TY  - JOUR
A1  - Stein, Katharina
A1  - Coulibaly, Drissa
A1  - Stenchly, Kathrin
A1  - Goetze, Dethardt
A1  - Porembski, Stefan
A1  - Lindner, André
A1  - Konaté, Souleymane
A1  - Linsenmair, Eduard K.
T1  - Bee pollination increases yield quantity and quality of cash crops in Burkina Faso, West Africa
JF  - Scientific Reports
N2  - Mutualistic biotic interactions as among flowering plants and their animal pollinators are a key component of biodiversity. Pollination, especially by insects, is a key element in ecosystem functioning, and hence constitutes an ecosystem service of global importance. Not only sexual reproduction of plants is ensured, but also yields are stabilized and genetic variability of crops is maintained, counteracting inbreeding depression and facilitating system resilience. While experiencing rapid environmental change, there is an increased demand for food and income security, especially in sub-Saharan communities, which are highly dependent on small scale agriculture. By combining exclusion experiments, pollinator surveys and field manipulations, this study for the first time quantifies the contribution of bee pollinators to smallholders’ production of the major cash crops, cotton and sesame, in Burkina Faso. Pollination by honeybees and wild bees significantly increased yield quantity and quality on average up to 62%, while exclusion of pollinators caused an average yield gap of 37% in cotton and 59% in sesame. Self-pollination revealed inbreeding depression effects on fruit set and low germination rates in the F1-generation. Our results highlight potential negative consequences of any pollinator decline, provoking risks to agriculture and compromising crop yields in sub-Saharan West Africa.
KW  - bees
KW  - pollination
KW  - Burkina Faso
KW  - cash crops
KW  - cotton
KW  - sesame
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-169914
VL  - 7
IS  - 17691
ER  -