Characteristics Of Natural Regeneration Of Quercus Liaotungensis Community

Quercus liaotungensis forest is a forest community widely distributed in north warm temperate zone, and Quercus liaotungensis is the most important forest specie of the deciduous forests, which contributed the ecological system to peak community in the warm temperate zone in China. It is also significantly important to keep of soil and water and keep the forest environment more stable. Meanwhile, it is an important ecological tree specie, which posess high values of exploitation and utilization. In our experiment, we conducted Quercus liaotungensis forest in the Huang long mountain of Northern Shaanxi Province, the Xiao long mountain of Gan Su Province, and the Ling kong mountain of Shanxi Province, respectively. Ninety standard plots under the forest canopy were set and sixty gaps were observed in forest gaps. In this article, the regeneration of Quercus liaotungensis forest was studied. The results are showed as follows:Firstly, we found that the style of regeneration of Quercus liaotungensis forest consisted of initiation and seed regeneration, and initiation was the main regeneration style. Quercus liaotungensis is the dominant specie of the Quercus liaotungensis forest regeneration seedling in the three districts. The ranks of density values of Quercus liaotungensis seedling in different district were the Huang long mountain>the Xiao long mountain>the Ling kong mountain. The ranks of density values of the Quercus liaotungensis seedling in different ecological condition were marginalization of forest gaps >forest gaps >under the canopy. The characteristics of the high structure of Quercus liaotungensis seedling: all presented that the number of seedling decresring with the increasing of height class. The ability of using ecology space of Quercus liaotungensis seedling in three districts in turn was that Ling kong mountain, Xiao long mountain and Huang long mountain.Secondly, the natural regeneration of Quercus liaotungensis forest in different slope aspect in turn presented: shady slope> semi-shady slope> semi-sunny slope > sunny slope. The seedling distribution in downhill position was more reasonable than others. The natural regeneration of Quercus liaotungensis forest needed not only sufficient illumination condition, but also certain shade condition. The best canopy density of regeneration seedling was 0.6～0.8. The factors which influence regeneration in turn were the altitudes, thickness of litter, grade of slope, the slope position, aspect of slope and canopy density.Thirdly, the basic characteristic of gaps was as follows: the size of gaps was 9.8～157m2. During the modes of gaps formation, most gaps observed were formed in cutting style. Illumination in gaps did not achieve the biggest value, the opening degree was only from 0.4 to 0.8. The majority gaps were formed by 1 to 2 gap makers. Every gap consisred of 7.7 edge - tree in average.The number of gaps which consisted of 6~10 edge-tree accounted for 81.7% of the total of gaps. The diversity of tree species seedling and brushwood layer from large to small was: fringe area of forest gaps, central area of forest gaps, under the canopy, respectively.Finally, the aggregate distribution of regeneration seedlings of Quercus liaotungensis was observed in different size of gaps, and different districts. The ranks of density values were the Xiao long mountain >the Huang long mountain>the Ling kong mountain, Small gaps>middle gaps>big gaps.The factors which influence regeneration of gaps were the opening degree of gaps, the area of gaps, altitudes, grade of slope, slope position and aspect.