Survival of a tertiary relict species, Liriodendron chinense (Magnoliaceae), in southern China, with special reference to village fengshui forests.

摘要

Premise of the study: We investigate factors supporting the persistence in southern China of a rare Tertiary relict tree species, Liriodendron chinense, which has been almost eliminated by recent land use conversion. We hypothesize that cultural practices and traditional sustainable forest resource uses provide niches for the species' regeneration that will complement infrequent natural disturbances, while the species' survival on remote mountain slopes where there are no humans depends on natural disturbances alone. Methods: We examined and analyzed various landscape contexts, community associations, age distributions, and regeneration patterns of Liriodendron chinense. Key results: Forest communities containing Liriodendron chinense were of three types: (1) village fengshui forests-mature forests dominated by Tertiary relict taxa Liriodendron, Toona, and Emmenopterys, protected for their supposed spiritual value; (2) young secondary forests near villages, dominated solely by Liriodendron; and (3) old secondary forest remnants on mountain slopes far from villages, dominated by Liriodendron with other Tertiary relicts of the genera Davidia and Sassafras. The age structure of Liriodendron indicated ample recruitment in the first two forest types, where the activities of local people have provided regeneration niches for the survival of this shade-intolerant pioneer species. On the remote mountain slopes that have never been converted to agriculture, Liriodendron has survived through regeneration made possible by natural disturbances. Conclusions: The traditional human land use, influenced by cultural values, has supplemented infrequent natural disturbances, providing regeneration niches for this and other Tertiary remnant species near villages in mountain valleys, while on uninhabited mountain slopes the species depends on natural disturbances to survive.Digital Object Identifier http://dx.doi.org/10.3732/ajb.1300057