Impact of nonnative feral pig removal on soil structure and nutrient availability in Hawaiian tropical montane wet forests

摘要: Conservation and restoration of ecosystems impacted by nonnative ungulates increasingly involves their removal exclusion. While the influence ungulate on plant communities is commonly monitored, impacts underlying ecological processes are seldom quantified. Here we examined how feral pig (Sus scrofa) from Hawaiian tropical montane wet forests affects soil physical chemical properties. Unique to this study, measurements were taken in paired sites inside outside five units representing a ~20 year, highly constrained chronosequence where other potentially confounding variables held constant. Additional targeted single exclosure areas characterized ‘low’ versus ‘high’ activity. Overall, increased stable aggregates porosity, decreased bulk density, water-filled pore space, moisture content. Further, nutrient regeneration as evidenced extractable cations, resin available NO3 − total inorganic N, enriched foliar δ15N. Increasing time since was positively related net nitrification N mineralization, negatively pH ammonification. Results both sampling consistent direction support central role modifying Changes properties following coincided with large increases understory vegetation cover, highlighting need better understand aboveground-belowground linkages removal.