天然白桦林的最优密度模型  

Optimal Stand Density Model for the Natural Forest of White Birch(Betula platyphylla)

作　　者：王维芳[1,2] 苏含英[1,2] 于凤华 李国春[1,2] 李长胜 秦家鼎 

机构地区：[1]东北林业大学 [2]黑龙江省林业勘察设计院

出　　处：《东北林业大学学报》1997年第6期6-10,共5页Journal of Northeast Forestry University

摘　　要：林分在其生长发育的各个阶段，都有一个最佳密度，使得最终主间伐合计的总收获量最大。为了找到这一密度系列，根据１９９４年在内蒙古大兴安岭林管局收集的２００块标准地及３９１株解析木的资料，以立木密度（Ｎ）作为控制变量，以林分蓄积为状态变量，以各阶段间伐的总收获量最大作为目标函数，利用动态规划的方法进行推导，得出了天然白桦林的最优密度模型。利用该模型，可以得到不同立地条件，不同年龄阶段的理论最优密度。对天然白桦林的营养面积进行了研究，提出了用树高承担值确定保留木株数的方法，只要根据年龄和立地条件确定树高承担值，就可通过优势木平均高获得营养面积，进而求得保留木株数。这种方法简便而实用，便于在生产实践中应用。During each period of growth and development, stand has a optimal density which can obtain the maximum of the final yield of cut-over and thinning. In order to find this density series, depended upon the data of 200 plots and 391 stem analysis trees for natural forest of Asian white birch (Betula platyphylla )collected in Daxing'an Mountains, of Inner Mongolia, making stand density(N) as control variable, stand volume as state variable, the maximum of total of each period's thinning yield as target function, using the method of dynamic program, the optimal density model of various periods for Betula platyphylla was deduced. According to this model, we can obtain the theoretically optimal density for various sites and age periods. Based on the study of nutrition area of Betula platyphylla, it is proposed to use the height-bearing value to obtain reserve trees' density. Once defining height-bearing value according to stand age and site, the nutrition area can be obtained through dominant trees' mean height, so reserve trees' density can be obtained. This method is simple and it's convenient to use in practice.

关 键 词：天然白桦林 动态规划 最优密度模型 

分 类 号：S758.52[农业科学—森林经理学] S792.153[农业科学—林学]