Relationship Of Korean Pine Growth And Development With Characteristics And Distribution Patterns Of Their Adjacent Broadleaf Trees Under Different Openning Degree

Korean Pine (Pinus koraiensis) broadleaved mixed zone is typical climax community in northeast mountainous in China. Due to large-scale unreasonable logging recently, original pine broadleaved mixed forest remained few at present, and stand gradually evolved into a secondary forest. How large area of secondary forests by artificial cultivation of pine made its restore into mature pine broad-leaved forest, which had become the urgent work. In this study, the Korean pine broadleaved mixed forest as objective, and based on the growth the relationship between the degree of pine saplings under the open canopy of broadleaf, different directions shade hardwood, hardwood and horizontal distance of Korean pine, hardwood special morphological characteristics were analyzed in Northeast Forestry University Maoer mountain experimental forest farm, in order to further study the effects of open degree on Korean pine growth under canopy. The results showed that: (1) Under open degree conditions, the effects of upper broadleaf direction on pine growth and development under canopy.Broadleaf located in the northeast of pine, when the open degree was 2, the annual diameter growth up to 0.55cm in pine, and when the open degree was 1, the lowest annual diameter growth was 0.34cm in pine. Broadleaf located in the north and northeast of pine, basal stem diameter growth of pine had no significant difference, and the rest of the directions were not significant.Under the same open degree conditions, broadleaf located in the northeast and southwest of pine, the annual diameter growth of pine was the largest. The annual diameter growth of pine was the lowest in northwest direction, and basal stem diameter growth of pine was highest in south and southwest direction, but was lowest in west and southwest direction. The height in pine seedlings in southwest and south direction was higher than west and northwest direction, while northeast direction and the other directions had no significant difference. On the whole, broadleaf located in northeast and southwest direction of pine, the effects arbor on the light understory trees was little.(2) The effects of the horizontal direction between upper broadleaf and pine on pine seedlings growth under different conditions of open degree. This study based on open degree, the further analyzed the effects of the horizontal direction between pine and broadleaf surrounded with pine on DBH, basal stem diameter growth, and height growth in pine seedlings. The results showed that DBH, basal stem diameter growth were increased with the distance enhanced under different open degree, while had no significant difference. When the open degree was 2, the distance between pine and broadleaf was above 4.5m, and the height growth was up to 0.51cm, compared with distance below 1.5m under the same open degree, which was 1.9 times.(3) The effects of morphology character on the growth of pine under canopy.The between with DBH of upper broadleaf and growth conditions was negative correlation. When DBH of the upper broadleaf was larger, the height and DBH growth of pine seedlings under canopy were lower. The broad-leaved branches also affected the growth of pine under canopy. The annual DBH, basal stem diameter growth, and height growth were increasing with the next branch height increased under different open degree conditions. When the next branch height was less than 3m, the average annual growth was 0.16cm under various open degree, which was 53.3% in the next branch height above 10m, and difference was particularly notable.