基于Apriori算法的浙西杉木用材林立地及生长因子关联分析

森林立地条件影响着林木的生长。为了充分挖掘立地因子与林分生长之间的内在联系，以杭州市临安区森林资源动态监测数据为基础，以杉木Cunninghamia lanceolata林为研究对象，运用差分方程法构建了基于Richard理论方程的地位指数模型；利用Apriori算法进行立地因子和林分生长因子的关联规则挖掘，得到175条置信度在80%以上、支持度在10%以上的因子关联规则，并从中提取了20条“林分因子-立地因子”规则。结果表明:影响临安区杉木用材林立地质量的主要因子是海拔、坡位、坡向、坡度级、土壤类型、土壤质地、土层厚度、腐殖质层厚度、林下植被种类和林下植被覆盖度，各类规则揭示了杉木林分立地因子和立地质量、立地因子和林分生长因子，林分因子和林龄之间存在的变化规律以及隐含的关联关系。

Chinese fir forest site association analysis and growth factors in western Zhejiang based on the Apriori algorithm

Forest site conditions affect the growth of trees. To fully delve into the internal relationship between site factors and stand growth factors, Chinese fir (Cunninghamia lanceolata) forest was taken as the research object, and a site index model based on Richard's theoretical equation was established using dynamic monitoring data of forest resources in Lin'an District of Hangzhou. The Apriori algorithm was used to explore the association rules between site and forest stand growth factors. Results showed 175 rules obtained with confidence over 80% and support over 10% and 20 rules of "stand growth factors-site factors" were extracted from them. The site factors which influenced site quality of Chinese fir timber forests in Lin'an District were altitude, slope position, slope aspect, gradient, soil type, soil texture, soil thickness, humus depth, species in the undergrowth, and degree of cover on the undergrowth through the rules. The rules revealed variation rules and hidden associations between site factors and stand quality, site factors and stand growth factors, as well as stand factors and stand age.