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›› 1958, Vol. 4 ›› Issue (4): 451-476.

• 论文及研究报告 • 上一篇    

毛竹干形和材积针算方法的初步研究

虞岳世 黄清民   

  1. 南京林业学校
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:1958-10-01 发布日期:1958-10-01

A PRELIMINARY STUDY ON THE STEM FORM OF BAMBOO(PHYLLOSTACHYS PUBESCENS)MAZELEX H.DE.LEHAIE AND THE METHOD OF CALCULATING ITS VOLUME

Yu Yueshi,Huang Qingmin   

  1. Nanking School of Forestry
  • Received:1900-01-01 Revised:1900-01-01 Online:1958-10-01 Published:1958-10-01

Abstract: 1.The objects of this study are:(1) to apprehend the stem from of ‘Phyllostachys pubeseens, (2)to seek a reasonable method of calculation for the investigation of bamboo plantation and the market trade. 2.Two batches of test materials are provided for this study.The first.contains 15 stems which were bought from The Wood Co.of Nanking.The second.contains 107 stems which were collected in Jan.1957 from Mao Mountain in the south of Kiangsu province. 3.As the investigation for volume calculating method is based on the analysis of stem form, professor B.K.Zaxapob's method were applied and the averages and relative values of external dia- meter (D).thickness (T) and empty internal diameter at different height of each of 102 stems (such as 0.0m.1/4H.1/2H.3/4H and let the D1/8H.T1/8H=100%) were calculated (see table 1.) Then.by means of constructing (see fig.1) and curve fitting.It is found that the stem form of the bamboo is similar to that of the tree.An approximate parabolic relationship of diameter to beight is shown in the formula below: y=109.78-76.62x-21.52x2(y=diameter,x=height all are relative values) The relative degrees of tapering in various stems are.however.rather coincident. 4.As the thickness of the stem wall is in inverse propertion to the increase of the height (see table 1).the empty internal form can not be identified with the external form of the stem.But in fig.3.they are still similar to each other with the exception of the base region. 5.Based on the above analysis.six kinds of formula for volume calculation were proposed on the basis of paraboloid of revolution.They are: ①V=πLT(1/2)(D(1/2)-T(1/2)) ②V=πL[(D1-T1)T1+(D2-T2)T2+...+(Dn-Tn)Tn]+πl′T′(D′-T′) ③V=πLT(D1+D2+...+Dn-nT)+πl′T′(D′-T′) ④V=x/4 L(T0+Tn)(D0+Dn-T0-Tn) ⑤V=π/2L[(D(1/4)-T)(1/4))T(1/4)+(D(3/4)-T(3/4))T(3/4)] ⑥V=x/6L[(D0-T0)T0+4(D(1/2)-T(1/2))T(1/2)+(Dn-Tn)Tn] Each formula was verified by the volume of each individual stem(including 14 stems from the 1st batch and 36 stems from the 2nd batch)measured with physical method.The accuracy of each one is shown in table 4. 6.The form quotient (q).form factor (f).coefficient of solid volume (c).coefficient of form volume (K=f.c) of each individual stem and averages of them were calculated and a graphical ar- rangement based on empirical data was made.It is found that the variation of the form factor is similar to that of the tree.And the empirical formula was obtained through curve fitting (the hy- perbola was adopted).f=1.40q2+0.150(?) The form factor table was thus constructed as table 8. 7.Table 10 shows that the variation of the coefficient of solid volume (c) is in inverse propo- rtion to the increase of the total height (H) or d.b.h.(D(1.3)). 8.There exists a certain hyperbolic correlation between K and H and q2. The empirical formula was derived in the same way and the table of coefficient of form volume was constructed (see table 8). 9.Based on the fifth formula (V=π/2L E (D(1/4)-T(1/4)) T(1/4)+(D(3/4)-T(3/4))T(3/4)] and by substituting the correlation between D(1.3) and the diameter and thickness (such as:D(1/4)=0.7787+ 0.78194 D(1.3).D(3/4)=0.55322+0..33679D(1.3).T(1/4)=0.32000+0.04809 D(1.3),T(3/4)=0.16813+0.02907 D(1.3))for the corresponding calculating factors in the formula.the following empirical formula of volume was derived: V=10-4(0.33195+0.50305 D(1.3)+0.06949 D(1.3)2) H After correcting the constant error of above empirical formula.the volume table of ‘Phyllostachys pubescens’ may be constructed (see table 18). 10.Owing to the fact that materials were obtained locally.the empirical formula of volume may be derived simply from the correlation between the volume and the d.b.h.(the power function was adopted). Log V=(?).95058+2.2646 Log D(1.3) 11.The correlation between the weight of stem and the d.b.h.is fit for a parabolic relationship. The empirical formula of weight and the weight table were produced in the same way.(see table 27). W=1.58125 D(1.3)+0.13556 D(1.3)2-7.774.