The Ecological Study Of Robinia Pseudoacacia Community In Fang-gan Restoration Region

Robinia pseudoacacia is a perfect hybrid tree and a pioneer tree species in vegetation restoration, which is high valuable to forest restoration and ecological building of temperate zone of China. We adopt field investigation measure and laboratory experiment measure to study Robinia pseudoacacia forest of Fang-gan restoration region. The content of study includs that population structure, growth dynamics, the LAI dynamics of arbor layer, shrub layer and herbage layer in forest, the flora of plants under forest, the typical community's variation of biomass, the decomposing of falling in forest. In the artifical forest, there are 4 typical communities, including Robinia pseudoacacia, Vitex negundo, Artemisia japonica and Themeda triandra+ Carex lanceolata.The results indicate that there are obvious two parts of population structure, one is Robinia pseudoacacia seedlings from age stage 2 to age stage 10 in shrub layer, the other is Robinia pseudoacacia arbor from age stage 17 to age stage 26 in arbor layer. The age stage of 11-16 is lack. The growth rate of height, canopy width and canopy length of Robinia pseudoacacia seedlings is larger than that of old ones. The forest age is about 30y, but the Robinia pseudoacacia seedlings have not grown to arbor layer. In the current condition, if the artificial forest is destroied, the forest will be in hard risk. The forest did not self-rejuvene and keep continued developmet. So we should keep continued protecting act, not destroy it.The results of LAI display that the LAI of arbor layer is larger than that of shrub and herbage layers. LAI of shrub and herbage layers increase fastly and early in Apr. of 2004y. The result display that in forest, the leaf overlap is low, and the under-forest plants develop leaves in early year when the forest did not form, in order to make full use of light.