Causal Factors and Ecological Characteristics of the Melia azedarach Community and Sprouting Regeneration after Felling

Abstract

Melia azedarach, which is attracting attention as an early-maturing tree species, is a domestic alien species in the Hyogo Prefecture, Japan, and has recently migrated to form dominant communities. Therefore, we investigated the causal factors and ecological characteristics of the M. azedarach community established on sabo dam sedimentation beds and changes in constituent tree species and biomass before and after logging in the M. azedarach community on the riverbed. As a result, the causal factors of the M. azedarach community were nearby seed sources and sunny areas formed by logging cedars. In addition, the establishment and growth of competitors of M. azedarach were hindered by the feeding of sika deer. Furthermore, in this community, the invasion of tall tree species was low due to the feeding of sika deer; therefore, although the shade tolerance of M. azedarach was low, the dominance of M. azedarach will continue for the time being. In the riverbed M. azedarach community, although M. azedarach and Ailanthus altissima competed before and after logging, the recovery of biomass due to the emergence and elongation of sprouting after logging tended to be faster in M. azedarach than in A. altissima.