As a result of long-term human activity, including deforestation, logging, fire and unsustainable agricultural practices, subtropical montane evergreen broad-leaved forest is now degraded and fragmented, and there is an increase in the amount of habitat edges. However, few studies have elucidated the regeneration of primary forest species, especially of dominant species, along an interior-edge-exterior gradient in relation to the subtropical evergreen broad-leaved forest area.
Aiming at quantifying the spatial distribution of primary forest species along the forest-field gradients, Prof. LIU Wenyao and his team conducted field observations on forest regeneration pattern of forest edge in subtropical montane evergreen broad-leaved forest in Ailao Mountain, SW China. Their results revealed that there was a higher abundance and richness of primary species, late secondary species and thorny lianas at the distances 0–50 m than at the distances more than 50 m from the edge into the forest exterior. At the distances ﹥50 m, no individuals of dominant canopy trees Lithocarpus xylocarpus, Castanopsis wattii, and L. jingdongensis were found, whereas the abundance of early pioneer shrub species and herbaceous cover was significantly greater. The richness of primary species showed a decrease with increasing distances from the forest edge to the exterior, particularly of medium-seeded primary species showing a drastic decrease. Moreover, no large-seeded primary species occurred at the distances﹥60 m. This study indicates that the forest edge as a buffer zone may be in favor of primary species regeneration. A dense shrub and herb layer, and seed dispersal may be the major factors limiting the forest regeneration farther from the forest edge. These suggest that management should give priority to the protection of buffer zones of this forest edge to facilitate forest recovery processes.
This research result has been published in the Journal of Plant Research (2010, 123: 751-762).