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依据改进Hegyi单木竞争模型计算林窗和林下不同龄级格氏栲幼苗的竞争强度,采用指数平滑模型对幼苗竞争强度数据进行优化,对优化后数据应用单一斜率变点法确定格氏栲幼苗最佳竞争范围.结果表明:1)在格氏栲天然林中,林窗和林下格氏栲幼苗平均竞争强度随着竞争距离增大而逐步降低,初期下降较快,下降到一定程度后明显变缓,存在变化幅度的转折点,即为幼苗的竞争范围.2)林窗和林下格氏栲幼苗竞争强度的三次指数平滑值在最佳平滑系数α为0.8和0.7时其均方误差值分别为0.401 5和0.385 1,单一斜率变点分析得出林窗和林下格氏栲幼苗最佳竞争范围分别是距对象木1.70 m和1.90 m.研究结果可为格氏栲幼苗竞争格局研究中确定幼苗竞争范围提供科学理论依据.
According to the improved Hegyi single-tree competition model, the competition intensity of seedlings of Castanopsis kawakamii was determined by using the exponential smoothing model, and the data of single slope variation The results showed as follows: 1) In the natural forest of Castanopsis kawakamii, the average competition intensity of seedlings of Castanopsis kawakamii and Betula platyphylla decreased gradually with the increase of competition distance, and the initial decline decreased rapidly to a certain degree And the turning point of the change range was the competition range of seedlings.2) The third exponential smoothing value of the competition intensity of Gap and Castanopsis kawakamii seedlings under the optimal smoothing coefficient α of 0.8 and 0.7 The error values were 0.401 5 and 0.385 1, respectively. The single-slope change point analysis showed that the optimal competitive range of M. grifola fruticosta was 1.70 m and 1.90 m, respectively. Pattern to determine the scope of seedling competition to provide a scientific basis for the theory.