The Relationship Between Growth And Stand Density Of The Artificial Forest Of Pinus Tabulaeformis In Daqing Mountains

The artificial Pinus tabulaeformis forest of 30 years old in Daqing Mountain was studied in this article, we studied stand factors, ground biomass and leaf area index of different densities.(1)The study on the relationship between density and growth factors of the artificial forest of Pinus tabulaeformis in Daqing Mountain showed: average chest height diameter and crown breadth decreased with the increase of stand density. And the relationship between them can be showed by the function of power and index .It is means that under a certain extent, the average diameter and crown breadth decreased with the increase of stand density. With the increase of stand density, the tree height didn't change remarkably. But the height diameter ratio of trees increased with the increased density. And the relationship between them can be simulated with logarithm curve. The critical maximum of stand density in Daqing Mountain, which affected growth factors, was 3000 stocks/ha in the sunny slope and 4000 stocks/ha in the shady slope. And it can be considered as the referenced criterion to control the stand density.(2)The results showed that the stand density affected both the individual biomass and the total biomass in unit area significantly. The individual biomass decreased with the increase of the stand density and varied less and less, and their relationship could be expressed by the equation y=axb. The total biomass in unit area increased with the increase of the stand density and varied less when the density increased to a value (It is 3000/ha in the slope facing south and is 4000 /ha in the northern slope of mountains.), and they could be expressed by the equation y=a+bln(x).The relationship between leaf area , leaf area index and density was significant. Leaf area index increased with the increase of stand density. It was larger in sunny slope than in shady slope under the similar density, and the index gap between different slope increased with the increase of stand density. The effect of density on individual leaf area and leaf area index were similar as ground biomass. and the Critical densities also applied to it .(3)Timber density increased with the increase of stand density,and the relationship could be expressed by the equation y=axb. Timber density of sunny slope was larger than shady slope in the similar density. By comparing the stand factors and ground biomass of same density,the results showed that aspect affected the growth of artificial forest of Pinus tabulaeformis significantly .Every index of sunny slope was more excellent than shady slope.