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作 者 ：徐德应 刘景芳 童书振

期 刊 ：林业科学 1993年 29卷 5期 页码：415-423

关键词：杉木人工林；林分密度；优化；模型；

Keywords:Chinese fir plantation, Stem density, Optimization, Model,

摘 要 ：DENTROL模型是根据全国杉木造林密度试验和杉木林抚育间伐强度试验的结果,参照新编的全国杉木人工林经营数表,分别杉木分布带、区和地位指数级,编制成的优化密度控制计算机模型。它主要以内部收益率为目标函数,辅以其它指标,实行全局优化判别。优化密度控制包括初植密度、间伐开始期、间伐强度、间伐次数、保留密度、主伐年龄和培育目标的确定,使最终的内部收益率为最大或接近最大。以12块抚育间伐试验标准地的数据,对模型的材积生长预测的精度进行检验,结果表明模型的材积预测标准差为±8.9%,系统误差为1.8%,符合生产实际的要求。根据计算,采用优化密度控制比非优化的对照区,按全国平均,每公顷净现值可提高321.7元,即提高17.0%。如仅以主要商品材基地——杉木分布区中带计算,则可提高经济效益47.3%,即每公顷可提高净现值892.4元。

Abstract:DENTROL(DENsity conTROL model) is a computer model for the opti-mization of stem densities of Chinese fir plantations, which is based on theNational Experiments of Planting Density, and Tending and Thinning ofChinese Fir Plantations, and referencing to the New National ManagementTable of Chinese Fir Plantation, and formed according to distribution zone,distribution area and site indexes. The concept of the optimization of densitycontrol is the selection of a series of elements concerning stem density of astand, including initial planting density, year of first thinning, thinning intensity, times of thinning, ages of harvesting, and planting aim, from whichthe final internal return rate (IRR) will be maximum or so. Data from 12plots in Tending and Thinning Experiment were used to test the accuracy ofthe model in predicting stem growth. The results showed that the standarddeviation was +/8.9%, the systemic error was 1.8%, which are enoughfor the demand of forestry production practice. According to calculations,based on the plantation of the whole country, the average net present valueper hectare of plantation managed with optimized stem density will increase(?)321. 7, bu 17.0% , and which will increase (?)892. 4, by 47.3% , if only basedon the main commercial timber base——the distribution area of Chinese firplantation.

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