Experimental test of effects of habitat heterogeneity and plant diversity on ant community

We investigated how an increase in the habitat heterogeneity and plant diversity affects to the ant community of a Mediterranean pastureland in Cordoba, southern Spain. We considered an area of 1600m 2 , with 24 (9 x 2m) fragments containing different numbers of shrub species ranging from 0 to 9 species depending on the treatment. The area between the fragments was maintained cleared by mowing. We compared ant species richness, diversity and community composition along three years (2000 to 2002), using pitfall traps. We observed an increase in the number of ant species along the three years, as well as an increase in the diversity index (P<0.04 in all cases). The abundance of many ant species was higher during the study period, reaching an increase of about 50% from the first year (Plagiolepis schmitzii, Camponotus micans, C. pillicornis and Cataglyphis velox). Our study shows that an increase in habitat heterogeneity and plant diversity is related with an increase on the species richness and diversity of the ant communities, as well as with an increase in the abundance of most species.