Dissemination and germination of seeds from Sahelian cattle faeces in Burkina Faso.
Agropastoralism has both positive and negative effects on the regeneration of agro-ecosystems. This study aims to determine the effects of the faeces of different ruminants on the dissemination and germination of species according to their functional traits. The faeces of cattle (Bos indicus), goats (Capra hircus) and sheep (Ovis aries) were sampled in 15 replicates at three seasonal periods of the year in 45 enclosures in the Sahelian zone of Burkina Faso. The seed potential and germination capacity of five agroforestry species (Balanites aegyptiaca, Faidherbia albida, Piliostigma reticulatum, Vachellia nilotica and Ziziphus mauritiana) and one invasive species (Senna obtusifolia) were determined. The results show that goat faeces contain more seeds of the agroforestry species while sheep disseminate more seeds of the invasive species. For all six species, the seed bank potential in goat faeces is 64% of the total potential as against 34% in sheep faeces and 2% in cattle faeces. This potential fluctuates throughout the year and is highest in faeces produced in the cool dry season, at 73% as against 21% in the warm dry season and 6% in the wet season. The control seeds and those from goat faeces had a longer germination time and duration and a greater speed and rate of germination than those in sheep and cattle faeces. Faeces ensure dissemination and influence the germination capacity of seeds, hence the crucial role of agropastoral practices in the regeneration characteristics of agro-ecosystems.