沙地樟子松边材宽度与胸径关系研究

对相同立地条件下的10、20、30、40年生樟子松人工固沙林进行胸径、边材厚度测定,分析不同年龄边材厚度与胸径相关关系及不同年龄边材生长特征。结果表明:10年生时平均边材宽度为6cm;20~30年生平均边材增幅小;30~40年生时边材增幅大。10年、20年生樟子松边材厚度与胸径关系模型符合抛物线模型,拟合方程分别为y=0.146 2 x~2-1.554 6 x+6.401 7(R~2=0.975 3)、y=-0.057 6 x~2+1.456 1 x-4.761 9(R~2=0.669 7);30年生樟子松东、南两个方位边材厚度与胸径关系可用曲线拟合,东方位符合指数模型,方程为y=0.980 1e0.081 1 x(R~2=0.733 7),南方位符合抛物线方程y=0.009 x~2-0.07 x+1.940 4(R~2=0.518 7)或指数方程y=1.082 7 e~(0.065 4 x)(R~2=0.516 4);40年生樟子松的东方位和北方位可用幂指数模型拟合,分别为y=0.196 5 x~(1.077 2)(R~2=0.476 8)和y=0.029 1 x~(1.748 8)(R~2=0.785 5),南、西方位的相关关系可用指数模型拟合,表达式分别为y=0.673 e~(0.104 7 x)(R~2=0.750 4)和y=0.455 8 e ~(0.123 84 x)(R~2=0.934 6)。不同年龄边材宽度显著差异,可以反映其生长状况、水分利用对策、物质生产等方面的特征。

Correlations between Sapwood Thickness and DHB of Pinus sylvestris var.mongolica in Sandy Land

DBH & sapwood of 10,20,30 & 40-year-old Pinus sylvestris var.mngolica sand-fixation forest were determined under the same site conditions.Growth features of sapwood with different ages,correlations between thickness of sapwood and DBH at different ages were analyzed.Result shows that mean sapwood width of 10-year-old Punus sylvestris var.mongolica is 6 cm;the increase of mean sapwood is little at 20-30year-old;the increase of mean sapwood is great at 30-40-year-old;correlations between sapwood thickness & DBH of 10,20-year-old Pinus Sylvestris var.mongolica coincidence parabolic model,the fitting equation is y=0.146 2 x2-1.554 6 x+6.401 7(R2=0.975 3),and y=-0.057 6 x2+1.456 1 x-4.761 9(R2=0.669 7),respectively.Sapwood thickness & DBH of 30-year-old Pinus sylvestris var.mongolica can be fit by curve in eastern and sorthern bearing,the eastern bearing coincidence exponential model,the model is y =0.980 1e0.081 1x (R2=0.733 7),the southern bearing coincidence parabolic equation: y =0.009 x2-0.07 x + 1.940 4 (R2=0.518 7) or exponential equation y =1.082 7e0.065 4 x(R2=0.516 4;sapwood thickness and DBH of 40-year-old Pinus sylvestris var.mongolica can be fit by power exponent in eastern and northern bearing,being y =0.196 5 x1.077 2(R2=0.476 8)and y =0.0291 x1.748 8(R2 =0.785 5)respectively;the correlation of southern bearing and westen bearing can be fit by exponent model,the expression is y =0.673e0.104 7x(R2=0.750 4)and y =0.455 8 e0.123 84x(R2=0.934 6).The significant differences in width of sapwood with different ages can reflect the characteristics of their growth status,water use countermeasures,and material production.