滇中一平浪林场云南松天然次生林生长规律研究

Study on Stand Growing Rules of Pinus yunnanensis Natural Secondary Forest in Yipinglang Forest Farm

以滇中一平浪林场云南松天然次生林树干解析资料为基础，采取标准样地法与标准木树干解析法，运用MATLAB统计软件，采用一元幂函数式、抛物线式、逻辑斯蒂式、对数曲线式、舒马克式分别平均木和优势木拟合并选出最优胸径、树高和材积生长模型，并对其生长规律进行研究。结果表明：所建立的最优生长模型经检验其拟合总体精度在96．67％～98．97％之间，拟合效果好，可用于研究区云南松天然次生林生长过程的预测。平均木和优势木存在两个速生期，分别为5～10a和35～40a，建议在10～15a，40～45a之间进行抚育间伐，提高林木生长量。直至50a，优势木和平均木的材积平均生长量和连年生长量两条曲线尚未相交，林分生长未达到数量成熟龄，说明其成熟期在50a后。至50a，优势木材积总生长量和连年生长量分别约为平均木的4倍和5倍，可见在云南松天然次生林经营管理过程当中进行优树选择有较高的增益。

The growth regularity of Pinus yunnanensis natural secondary forest stand in Yipinglang forest farm was studied,based on the stem data and with the methods of standard plot and stem analysis.Six e-quations,a power function,parabolic,logistic,logarithmic curve,michael schumacher models,were used to established the growth model systems with average and dominant tree data with MATLAB statistic soft-ware.Then the optimal mathematical growth models were chosen by regression analysis.The results showed that:the fitting precision of the optimal mathematical growth models is between 96.67% and 98.97%.It was clear that the predicting effects of these models had good fitting precision and adaptability for the tree growth process,so they could be used to predict the study area of Pinus yunnanensis natural secondary forest growth.There are two fast-growing periods of average and dominant tree,which are 5 ~10a and 35 ~40a.Proper intermediate cutting was suggested during the age of 10 ~15 and 40 ~45 to pro-mote the fast growth of stand.The current annual volume increment curve and mean annual volume incre-ment curve didn’t meet in 50 years,indicating that the forest didn’t reach its quantitative maturity age, and its quantitative maturity stage was after 50 years.In 50 years,the total volume increment and the cur-rent annual volume increment of the dominant tree are 4 and 5 times more than that of the average tree, showing strong beneficial in artificial selection.