Modelling Individual Tree Diameter Growth of Quercus mongolica Secondary Forest in the Northeast of China

Quercus mongolica secondary forest is widely distributed in the northeast of China, but it usually has low productivity, unstable structure, poor health, and biodiversity. Diameter a tree variable that commonly used for growth measurement, to provide basis management decision. Two level generalized linear mixed effects individual diameter model were developed using data from two times surveys 12 Q. permanent plots among Wangqing farms. Random 14 species introduced into basic consisting three factors: size, competition surrounding trees, site quality. The results showed initial at breast height(DBH) was most important affecting growth, followed by competition, while effect quality on not significant. Compared with model, prediction accuracy improved 17.69 %, where R2 reached 0.6805, indicating suitable individual-tree mongolica.