Abstract:

Linear sampling plots were set up with a 14 years old plantation of Castanopsis hystrix in Fubo Experimental Station of Experimental Center of Tropical Forestry,Chinese Academy of Forestry in Guangxi,China.The effects of small scale slope level and microchange on tree growth and soil properties were studied to provide precise techniques for the selection of afforestation site for the cultivation of large diameter timber of valuable tree species.The result showed that:(1)the tree height and DBH decreased with the increase of slope position,and the influence of different slope positions on tree height and DBH was significantly different;(2)Soil nutrient elements,pH and soil organic matter were negatively correlated with slope height.That is,the higher the slope position,the smaller the value of each index,and the difference of pH,total P and K content between different slope levels reached a significant level;(3)Under the mild soil drought in spring,the difference of water content among different slope levels was not significant.It is suggested that according to the difference of site conditions of water and fertilizer for different tree species,different tree species should be arranged in the upper and lower slope positions when the slope length is more than 60m,and different tree species should be arranged in three slope positions when the slope length is more than 100m.

Key words: step-change of slope position, Castanopsis hystrix, growth, linear sample plot, slope position effect of growth