| Taxus chinensis var. mairei is a precious, endangered and first-class protected plant species in China. The yew shows an urgent problem on natural regeneration in most distribution area owing to the sparse population, low seed production, strong seed dormancy, weak competitiveness with other species and so on. A successful regeneration population with thousands of individuals occured in Xianyu Mountain in south Anhui Province from five parent trees. We studied the natural regeneration, population and community characteristics from Oct. to Dec. in 2006 and 2007 respectively. The results showed as the followings:1. The seeds fate of T. chinensis var. mairei showed three ways: Firstly, total 1615 seeds dropped by weight or other factors, and remained under the parent trees, which accounted for 24.57% of seeds production of parent treeâ‘ in 2007. Some seeds were eaten by insects or decayed. Secondly, seeds were foraged by birds. All 12 species of birds were found to feed on the seeds, while 7 species of them devoured the intact seeds. The arils were digested while seeds were transported to the sites far away mother trees, where might be adequate for seeds germination and further growth. The quantity of seeds eaten by birds was achieved to 2959 in 2007, which was 45.01% of the total number of seeds produced by parent treeâ‘ . Thirdly, the seeds were picked or plucked by local people. About 2000 seeds were plucked, which accounted for 30.42% of total number.2. There were 1338 individuals of T. chinensis var. mairei in 2006, and 1214 individuals in 2007 respectively, of which the number of seedlings height less than 30 cm accounted for 80%. The age structure appeared to be a type of pyramid, and the survival curve was Deevy-â…¢type. The population was presented a clumped spatial pattern. The spatial pattern in different development stages changed from aggregation to random. The high peak of death rate of the population was 17.19%, appeared inâ… 1 stadium, which about 43.64% of the death number. But some individuals had being survived and vegetated. The dynamic analysis showed that the natural regeneration population was of slowly increasing.3. The T. chinensis var. mairei community with complicated species structure has high species diversity. The species diversity index was 3.35, and the evenness index was 0.82. There were 74 species of plants which belonging to 50 genera, 35 families. The vertical structure consisted of trees layer, shrub layer, herb layer, and interlamellar plants. In different layers, the species diversity index of shrub layer was bigger than tree layer and herb layer. T. chinensis var. mairei was of broad niche. This showed that T. chinensis var. mairei was adaped to its habitat.The interspecific associations between T. chinensis var. mairei and main tree and shrub population were analyzed. The result showed that there was no significance in the interspecific associations. And the niche overlap between T. chinensis var. mairei and other populations was not large at all. Based on the results, it might be inferred that the community was at a successional stage. Our research suggests that T. chinensis var. mairei population grew well in the community with moderate canopy density and high species diversity which was low in tree layer but high in the shrub layer.
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