The acceleration of succession for the restoration of the mixed-broadleaved Korean pine forests in Northeast China

There are large amounts of clear-cuts and secondary forests in Northeast China. In order to preserve habitats of biodiversity and decrease ecological disasters, it now becomes urgent to restore them to the climax. An adapted forest dynamics model is used to simulate the change in tree species composition, density, and stem productivity of forests regenerating from clear-cuts of the mixed-broadleaved Korean pine forest (MKPF) and the introduction of species over 100 years in the region. The model shows that the restoration of climax forests on these sites can be accelerated by the introduction of proper tree species. For the current secondary forest of Quercus mongolica, Populus davidiana and Betula platyphylla, if the medium-type of shade tolerant tree species are introduced into the communities, the dynamics of tree species will change, and the stem productivity will decrease by 20%. If Larix olgensis is introduced into the forest communities, it will become dominant in the forests, with stem productivity increasing about 110%. If Pinus koraiensis is introduced, it will dominate the communities after 90-100 years, although the density and stem productivity will not change significantly. If P. koraiensis is introduced into the current secondary forest of medium-type trees, the dynamics of the forest will change significantly and the growth of medium-type trees will increase after 20 years. If the medium-type trees are introduced into the plantations of pure R koraiensis, both the tree density and stem productivity will increase dramatically, and the earlier stem divergence, earlier branching, of P. koraiensis can be improved. (C) 2002 Elsevier Science B.V. All rights reserved.