Pollination knowledge among local farmers in northern Tanzania and the role of traditional agroforestry practices in promoting pollinator forage plants

Pollination services by insects contribute strongly to food security and ecosystem stability. However, especially in Africa, little is known about farmer's knowledge and awareness of pollination services. Here, we first surveyed home garden farmers about their knowledge on pollination services, and their ability to recognize insect pollinators. Then we evaluated their home gardens for the availability of pollinator forage resources. We found that a majority of the farmers (89.1%) were not aware of pollination services and that awareness was higher for males and those with higher education levels. All farmers were able to recognize at least one insect species (especially, Apis mellifera) but most farmers did not know them as pollinators. We also found that 293 woody plant species from 62 families in Chagga home gardens (CHGs), provided insect pollinator forage. There was higher alpha diversity for exotic forage plants but higher gamma diversity for natives. The increase in diversity of pollinator forage plants reduced the temporal variability of flower richness. Our findings suggest that farmers should be made more aware of pollination services as well as insect pollinators specifically regarding their benefits to increase willingness to conserve them. Awareness programs should be accessible to women and those with little formal education as they exhibit the least knowledge. Also, various media tools should be used for effective dissemination to the different target audiences. Our findings also provide evidence that if managed properly some traditional agricultural land use systems can enhance pollination services by providing diverse forage resources for insect pollinators.