马尾松采脂林胸径破坏致材积测量误差的修正

经进行调查和试验表明，用马尾松采脂林被割胸径的测量值和树高，查符合精度要求的二元材积表，所得材积相对误差高达３０％以上．为此，在分析修正误差可能途径的基础上，研究了干基不同高度直径与胸径的相关关系，并建立了相关模型．结果表明，距地面１０ｃｍ，１５ｃｍ和２０ｃｍ处的干基直径与胸径的关系极为紧密．根据Ｄ１．３—Ｄ０．１０，Ｄ１．３—Ｄ０．１５和Ｄ１．３—Ｄ０．２０相关模型修正的胸径测量材积，在可靠性为９５％时，精度均可达到９７％以上．

Revision of the Wood Volume Measuring Error Resulted from the Tapped DBH of Pinus massoniana Forest for Resin Tapping

The results of investigations and experiments show that when a qualified Two-Element Volume Table is compared with the tapped DBH Values and tree heights of a tapping forest of Pinus massoniana Lamb.,the relative error of the corresponding wood Volume is up to 30% or above.For this reason, the interrelations between diameters at different heights of butt and DBH are explored, and the interrelation models are set up.The result of model analysis also shows that the relationship between the butt diameters at 10cm,15cm and 20cm above ground and DBH is very close.with the DBH values revised by the models of D1.3-D0.10, D1.3-D0.15 and D1.3-D0.20,the Valume measurement precision can reach 97% or above whell its reliability is 95%.