Abstract:

This paper analyzed the effects of different tending methods on the tree growth and soil physicochemical properties in birch forest,based on a research conducted in a birch forest of Hebei Mulan Weichang State-owned Forest Farm.The results showed that:1)Effects on DBH:No significant difference between UM and CK,while the effect of quality management(QM)was significantly higher than the CK after 4 years.2)Effects on tree height:There was no significant difference on tree height growth.3)Effects on crown width:QM>UM>CK after 2 years,significantly;QM and UM both were significantly higher than the CK after 4 and 6 years,but there was no significant difference between QM and UM.4)Effects on average annual volume growth:No significant difference among QM,UM,and CK after 2 years.However,QM was significantly higher than UM and CK after 4 and 6 years.5)There was no significant difference of effect on PH value in 0~20 cm and 20~40 cm soil layers.6)In the 0~20 cm soil layer,the content of organic matter,alkali-hydrolyzed nitrogen,available phosphorus,and available potassium were all QM>UM>CK,with significant differences.In the 20~40 cm soil layer,there was no difference in the content of available potassium;the content of alkali hydrolyzed nitrogen was QM>UM>CK,with significant differences;effective phosphorus content was CK>UM>QM,with significant differences;the organic matter content of QM was significantly higher than that of UM and CK,but there was no difference between UM and CK.

Key words: forest tending, quality management, traditional management, secondary birch forest, tree growth, soil physicochemical properties