| Creator |
|
|
|
|
|
|
|
| Language |
|
| Publisher |
|
|
|
| Date |
|
| Source Title |
|
| Vol |
|
| First Page |
|
| Last Page |
|
| Publication Type |
|
| Access Rights |
|
| JaLC DOI |
|
| Abstract |
九州大学宮崎演習林内の14年生クヌギ初代林を対象として，林分相対幹曲線に基づく径級別原木生産予測の可能性について検討した．まず，調査地内の19本を対象とした正常相対直径列の測定値をもとに，3次多項式で表現される林分相対幹曲線を導出し，適合精度で当てはまりの良否を判定した．次に，標本木として選定した20本を対象とし，林分相対幹曲線に基づく径級別原木生産本数予測を行い，実際の径級別本数と適合度検定法に...より比較検討した．その結果，本対象クヌギ林の林分相対幹曲線として次の3次多項式が得られた．$ y＝0.3833940x^3 - 0.3589740x^2 + 1.1236385x $この適合精度は，梢端と根張りを除いた部分の平均で6．07％と比較的良好な結果であった．また，この林分相対幹曲線に基づいた径級別本数予測方法は，末口直径の平均，径級別本数分布，採材材積および必要種駒数のいずれにおいても，実測値とほぼ等しかったことから，本方法は実用的かつ有効なものであると考えられた．
The purpose of this study was to investigate the availability of the prediction method for log production numbers in each diameter class of a 14-year-old kunugi (Quercus acutissima Carr.) stand based on average relative stem curve. By using the relative-diameter-series of 19 kunugi trees, the average relative stem curve described by an equation of the third degree was obtained as follows; $ y = 0.3833940x^3 - 0.3589740x^2 - 1.1236385x $ Log numbers in each diameter class were calculated using the stem curve equation. Both actual and predicted distributions of log numbers were examined by the test of goodness of fit. The null hypothesis that stated two distributions had no difference was accepted at a 0.01 level of significance. In addition, the average top-end diameters of two log number distributions were almost equal. As a result, it is possible to predict log numbers in each diameter class of kunugi based on the average relative stem curve. This method is available for practical use.show more
|
Export Mendeley
p025