Effects of litter removal on arthropod communities in pine plantations

Natural and anthropogenic disturbances can cause abrupt changes in trophic interactions by altering the rate, timing, or composition of organic inputs to ecological systems which in turn can shift patterns of species dominance. We examined the short-term effects of litter removal on soil fauna in pine plantations of three different species (longleaf, Pinus palustris ; loblolly, P. taeda ; and slash, P. elliottii ) using a manipulative experiment, with the goal of examining differences among dominant orders of arthropods and differences among timber types. We sampled arthropods once per month for 6 months immediately following raking, and found that removal of the litter caused significant changes to abundance or presence of five of the nine dominant orders. Reductions in abundances of arthropod orders were most apparent in loblolly pine stands, while increases in abundance were more common in longleaf and slash pine stands. The differential impact among orders suggests that removal of the litter layer is likely to alter trophic interactions by changing the relative abundance of functional groups. Repeated litter removal via raking could have negative repercussions on ecosystem stability. Finally, nutrient additions through fertilization seem unlikely to mitigate the changes imposed on the arthropod community through litter removal.