日本落叶松幼龄材干缩性能轴向变异

测定了建始县长岭岗林场引种栽培的12a生日本落叶松标准木干缩性能指标，并分析了它们在轴向上的变异，结果表明：径向全干干缩率为4．63，弦向全干干缩率为6．82，径向气干干缩率为2．41，弦向气干干缩率为3．92，体积气干干缩率为6．49，以上指标在轴向不同部位差异不显著，但有由基部至梢部逐渐变小的趋势；全干差异干缩为1．47，气干差异干缩为1．62，在轴向变异不明显且相对较稳定；体积全干干缩率随轴向部位变化而差异显著，且主要存在于基部与近梢部之间．

Research on the Axial Variation Pattern of the Shrinkage of Larrix kaempfri(lamb.)carr. Juvenile Wood

The shrinkages of the 12-year-old Larrix kaempfri(lamb.)carr. normal tree in Chang Lingang forest farm in country Jianshi are measured, and their axial variation patterns are analyzed. It shows that the radial-shrinkage of absoulute-dried wood is 4.63 percent and tangential-shrinkage is 6.82 percent .As air-dried wood, its radial shrinkage is 2.41 percent, tangential-shrinkage is 3.92 percent and volume--shrinkage is 6.49. Those indexes have no obvious difference in axis at 0.05 level variance. It has a tendency to reduce gradually from the bottom to the top of the trunk. At the same time,the ratio of tangential to radial shrinkage of absulute-dried wood is1.47 and air-dried wood is 1.62. They are relatively stable in axis. The volume-shrinkage difference among the positions on the axial line of the trunk is significant . And the main difference is between the lower and the positions near the top.