Long-term change in ground-layer vegetation of deciduous.pdfVIP

Journal of Blackwell Publishing, Ltd. Ecology 2005 Long-term change in ground-layer vegetation of deciduous 93, 202–213 forests of the North Carolina Piedmont, USA KRISTIN TAVERNA*, ROBERT K. PEET and LAURA C. PHILLIPS Curriculum in Ecology, CB#3275, University of North Carolina, Chapel Hill, NC 27599–3275, USA Summary 1 In Southeastern North America residual mature deciduous forests have long been assumed to represent the stable endpoint of succession, with local compositional var- iation reflecting primarily variation in soils and topographic position. However, the long- term stability of understorey vegetation in this region has rarely been examined due to the lack of reliable baseline data. 2 We resampled a series of permanently marked vegetation plots spanning a range of soil and site conditions in the Piedmont of North Carolina to evaluate compositional change in the understorey of putative ‘climax’ hardwood forests over a 23-year period. We examined all ground-layer species for change in total and native species richness at 25 m2 2 and 1000 m , change in species composition and variation in richness and composition with environment. 3 Although native and total species richness remained nearly constant, there was a sig- nificant decline in herb richness balanced by a strong increase in tree seedling richness.