Structure of Ant Communities at the Harvard Forest

• Investigators: Aaron Ellison, Nicholas Gotelli
• Contact: Aaron Ellison
• Start date: 2003-05-01
• End date: ongoing
• Location: Prospect Hill Tract and Simes Tract (Harvard Forest)
• Latitude: +42.46 to +42.55
• Longitude: -72.22 to -72.17
• Elevation: 210 to 420 meters
• Taxa: Formicidae (ants)
• Keywords: ants, biodiversity, hemlock
• Abstract:

  In biomass and ecological dominance, ants are the most important invertebrate taxon in terrestrial ecosystems and they can alter significantly fundamental processes and dynamics of soil ecosystems. Relative to deciduous stands, hemlock stands are depauperate in ant species that are linked to differences in rates of soil turnover and nutrient mineralization between these forest types. In both hemlock and deciduous stands, we will document ant species richness and abundance; assess their role in soil nutrient cycling; determine temporal trajectories of ant community assembly as hemlock declines following woolly adelgid infestation, and is subsequently replaced by birch; and discover how these trajectories influence nutrient availability during this transition.

• Methods:

  We will use a modified version of the Ants of the Leaf Litter (ALL) protocol tailored for hemlock and deciduous stands. In each plot across the Harvard Forest space-for-time transect (see project HF021, HF081, HF083) in which we sample for hemlock woolly adelgid, at Prospect Hill, and in each experimental plot on the Simes Tract, a 10 x 10 m sampling grid (2.5 m spacing) will be established. At each point in these grids, pitfall traps (95-mm diameter cups with 20-ml dilute soapy water) will be buried so that the upper lip of each trap is flush with the soil (N = 25 traps/grid). Traps will be left in place for 48 h. Trap contents will be fixed in the field in 95% EtOH. Pitfall trapping will be supplemented with tuna-fish baiting at each grid point for 3 h during the middle of the day, and 1 h of active searching and hand-collecting adjacent to the grid. Four 1L litter samples will be collected in each stand and ants extracted from the litter using Berlese funnels and Winkler sacks. Samples will be identified to species and vouchered at Harvard's Museum of Comparative Zoology. Nitrogen mineralization rates will be assessed in areas of different ant diversity and density (as identified through sampling) in the experimental plots and across the space-for-time transect using buried bags and standard assays in parallel with studies of soil ecosystem dynamics (see HF083).

• Related datasets: HF021 HF081 HF083