Ants are highly diverse, widespread, and abundant organisms playing important roles in ecosystem functioning. For these reasons, it is useful to know what structures their diversity.  Biodiversity is ultimately constrained by energy availability and the relationship between energy and diversity has been considered at global scales. Energy flux measured as net primary productivity (NPP), however, also varies considerably at landscape scales. In this work, we asked if patterns of ant diversity within a landscape can be predicted by variation in energy flux. To answer this question, we studied ant biodiversity and its relationship to NPP in the Chihuahuan Desert. This study was carried out at the Jornada Basin in southern New Mexico, in a portion of about 100,000 ha that comprises a variety of soils and geomorphology that result in substantial differences in NPP. We measured the peak standing crop biomass (as a proxy for NPP) of 20 sites that comprise 5 different types of vegetation states (grasslands, shrublands and ecotones between them), as well as the richness, abundance and biomass of ants.

Results/Conclusions

Preliminary results show that there is not a direct relationship between NPP and total richness, abundance or biomass of ants. However, when ants were divided into trophic guilds we found that biomass and abundance of small granivore ants and scavenger ants were positively related to the biomass of graminoid and shrub/succulent plants, respectively.  We emphasize the value of the inclusion of an energy-based perspective in linking ant measurements to ecosystem attributes, especially when biodiversity partitioned into appropriate functional groups.