Impacts of silvicultural practices on soil and litter arthropod diversity in a Texas pine plantation

In this study we used the diversity of soil and litter arthropods as a metric for evaluating the ecological effects of silvicultural practices of various intensities in a loblolly pine (Pinus taeda L.) forest ecosystem. The treatments included low and high intensity harvesting, soil bedding, chemical herbicide application, and nitrogen and phosphorus fertilization. Soil and litter cores were used to sample arthropods after harvesting. In the first year following removal of trees, species diversity was higher in hand-fell, hole-only harvested plots than in mechanical, whole-tree harvested plots and higher in non-bedded plots than in bedded plots. However, these differences did not persist into the second year following harvesting. The recovery of undergrowth vegetation in the second year and the development of a rudimentary litter layer may have increased diversity in the more intensively treated plots. Arthropod species richness increased following nitrogen and phosphorus fertilization, but Shannon diversity did not. This indicates that the arthropod community had responded to fertilization with a shift in community composition. The rapid recovery of arthropod diversity in the second year following tree removal suggests that the silvicultural treatments used at this site did not put long-term productivity at risk. Comparisons with other similar studies suggest that when aiming for sustainable forest management, the particular silvicultural practices that allow for ecosystem recovery may depend on local and regional conditions. (C) 2000 Elsevier Science B.V. All rights reserved.