40 years of Studies on the Relationships Between Grass Species, N Turnover and Nutrient Cycling in the Lamto Reserve in the Ivory Coast (Côte d’Ivoire)

The Lamto Station, dominated by grass savannas, was created in 1963. Among other problems, the relationships between savanna grasses (mainly Andropogoneae supertribe) and nutrient cycling, mainly nitrogen (N), have been intensively studied. Such grass systems are of major interest. Savannas represent 25% of terrestrial biomes and are second to tropical forests in the contribution to terrestrial primary production and are predominant in African social and economic environments. The Andropogoneae grasses are of particular interest for pastures. Second, savannas are generally extremely nutrient-poor, especially for N, which often limits productivity. Third, little is known about possible controls of grasses on N processes (e.g. nitrification) which could provide plants with potential advantages in competing for N, and induce changes in system N balance. Finally, these areas are considered to be non-emitting for NO and N2O as a result of extremely low nitrificatio