The abundance and dry biomass of canopy-dwelling arthropods (insects and small spiders) was tracked over five summers (2010-2014) at four sites near Toolik Field Station, Alaska. At each site, a shrub-dominant and tussock-tundra habitat was chosen for sampling, for a total of 8 sampling locations. At each sampling location, a 100-meter transect was established. Arthropods were sampled along the transect weekly by passing a sweepnet through and over the vegetation. After killing the arthropods with pest strips and freezing, they were sorted from the associated leaf litter and counted.
Arthropods (spiders and insects) were collected three times during the 2013 summer using pitfall traps and vacuum sampling in plots fertilized with Nitrogen and Phosphorus for 24 years, and in control plots, in an experiment established near Toolik Field Station, Alaska. Pitfall traps were placed for 48-hour intervals; vacuum samples were taken in a 1m2 area. Collected invertebrates were counted and identified to order or family.