| Based on plot investigation, transect plot investigation and radial growth analysis, we studied the population characteristics, disturbance effect of gap of Neolitsea aurata var. glauca in Jinyun Mountain and its regeneration.Analysis of size structure showed that each size class of Neolitsea aurata var. glauca had quite a lot of individuals. It implies that the regeneration of Neolitsea aurata var. glauca was continuous in time. A good number of saplings and middle-sized piants were found and most of them were individuals of DBH ranging from 2 to 4 cm. The number of old individuals were relatively small. So Neolitsea aurata var. glauca population was a growing population. At the same special location of small area(such as 500 m2), Neolitsea aurata var. glauca could reach the canopy and became the dominant species of the community. In the typical Neolitsea aurata var. glauca community the importance value of Neolitsea aurata var. glauca at shrub layer ranked the first, and became the most important species.Gap disturbance had different effects on the density, frequency, distribution of size class, spatial distribution pattern, radial growth pattern of Neolitsea aurata var. glauca population. Population density: Gaps > Ridge gaps> No-gaps; Population frequency: Gaps > Ridge gaps> No-gaps. Neolitsea aurata var. glauca in gaps were all individuals of DBH ranging from 1 to 5 cm, individuals of DBH >5 cm were rare. Neolitsea aurata var. glauca in ridge gaps were almost individuals of DBH ranging from 1 to 4 cm, and the number of individuals in ridge gaps are smaller than gaps. In no-gaps there were no individuals of DBH ranging from 1 to 3 cm. The individuals of Neolitsea aurata var. glauca in gaps showed clumped distribution. The annual radial growth in latest 5 years in gaps was significantly larger than that in placeswithout gaps.The radial growth of canopy Neolitsea aurata var. glanca in Jinyun Mountain exhibited 5 distinct patterns. Pattern I (29.4%), the radial growth was not suppressed obviously. Pattern II (27. 5%), suppression on radial growth lasted for a long time and was released eventually. Pattern 111(12.8%), fast growth for a long time and suppression occurred finally. Pattern IV (22.6%), fast growth alterated with growth suppression. Pattern V(7.7%), continuous growth suppression. It was found that 56.6-100% of Neolitsea aurata var. glauca showed some time of suppression during their canopy recruitment. The average number of suppression events was 1-1.9, the average total length of suppression time was 11.3-16.7 a, the duration of longest suppression was 26 a. 35.7-75.0% of Neolitsea aurata var. glauca experienced periods of release during their canopy recruitment. The average number of release events was 1.1-1.5, the average total length of release time was 15.3-21.5 a, the duration of longest release was 29 a, and the average age when the release was identified was 19.2-37.5 a, ranging 11 to 55 a.Gap disturbance had important effects on the regeneration of Neolitsea aurata var. glauca population. During the growth of Neolitsea aurata var. glauca entered into canopy layer of the community, 35.7-75.0% of the canopy Neolitsea aurata var. glauca experienced at least one time of release(the duration of release was 10-29 a). These Neolitsea aurata var. glauca followed gap-dependent regeneration. They could undergo a long period in shady environment, once a gap emerged, they would exploite the sunlight, and grow quickly into the canopy layer. Release caused by occurrence of gap of several times could make Neolitsea aurata var. glauca a dominant species. With the process of succession the status of Neolitsea aurata var. glauca in community would change. Neolitsea aurata var. glauca would probably grow into the dominant species. 7.7% of canopy Neolitsea aurata var. glauca were suppressed all along, no release, but they still reached the canopy layer. This meant that this small parts of Neolitsea aurata var. glauca could regenerate under the closed canopy, which was superior to the regene...
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