the fauna of Ambondrona lowlands, Mahajanga, Madagascar

Market gardening in Ambondrona plays an important role in supplying leafy vegetables to the city of Mahajanga. It is an intensive form of farming characterized by strong seasonality. An inventory of fauna in the Ambondrona lowlands, Mahajanga, identified 76 genera and species grouped into 44 families and 15 orders. Harmful families, particularly phytophagous ones, are still numerous compared to beneficial families, even at the species level. Plant types, crop succession, and the two types of land have a significant effect on nematode abundance. Nematodes are more abundant after lettuce cultivation than after short-cycle leafy vegetables. Earthworm abundance increases at the end of each crop cycle. Significant effects of crop cycles and fertilization levels on earthworm abundance were observed on the plots studied. In cultivated systems, soil moisture and temperature are the parameters that most influence earthworm population dynamics.