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本研究以杉木人工林标准地为材料,以M=aHt~b·N~c、M=aD~b·N~c式为等树高线、等直径线数学模型。经验证,此式及其参数较充分、准确地反映了林分密度与蓄积的数量关系及变化规律。因此,求解出即可直接绘制。此法省去了以单因子选择树种以及树种不同地区、不同生长状况数学模型之困苦,不需修匀;精度高,较为简捷。林分最大密度线,应用林分密度与平均直径的规律,以大样本饱和或接近饱和密度标地为材料,用N=aD~b式求出参数;将b值代入各标地,求出最大am值。用am、b值解出各径级最大株数,并代入等直径线数学模型,得各径级最大蓄积,联结各最大蓄积点即成林分最大密度线。经验证,此方法及结果正确。
In this study, Cunninghamia lanceolata plantation was used as a standard, with M = aHt ~ b · N ~ c and M = aD ~ b · N ~ c as the tree height and diameter line mathematical model. Proved that this formula and its parameters more fully and accurately reflect the relationship between the quantity and volume of forest density and changes in law. Therefore, the solution can be drawn directly. This method eliminates the difficulty of selecting the tree species by single factor and the mathematical models of different growth regions in different regions of the tree species without the need of smoothing; the precision is high and the method is relatively simple. According to the law of forest stand density and average diameter, using the index of large sample saturation or near saturation density as material, using N = aD ~ b formula to get the parameters; The maximum am value. Using am, b value to get the maximum number of each diameter class, and into the equal diameter line mathematical model, the diameter of the largest accumulation, the largest accumulation of points that link is the maximum density of forest stand. Proved, this method and the result is correct.