Plant species richness responses to management practices in chestnut (Castanea sativa Mill.) forests and coppice stands in the Cévennes mountains (southern France)

Abstract

We compared plant species diversity in cut (coppiced) and uncut (22 yrs old) chestnut stands of the Cévennes in southern France over a 6-year period by measuring species richness, Shannon-Weaver biodiversity index, Leaf Area Index (LAI), and life form spectra. Species richness increased six-fold immediately after the clear-cut from 5 species in the old coppice stand before the clear-cut to 30 species 2 years after the cut, but subsequently decreased over the 6-year period to reach 15-16 species in a 100 m" plot (n = 15). The Shannon-Weaver diversity index behaved like species richness. LAI increased during this period, but there were no statistically significant relationships between the diversity indices and LAI. The life form spectra were also greatly modified after the clear-cut. These changes mainly concerned the number of hemicryptophytes which increased significantly. This behavior is very different from that observed in old field succession where therophytes (annuals) are the first invaders of the open areas. Finally we discuss the consequences of various land use practices on the conservation of plant species diversity in these two types of chestnut dominated ecosystems.