洞庭湖区短轮伐期杨树人工林生物量调查

The biomass investigation of short rotation period of populus plantation in Dongting Lake area

为实现杨树人工林的分类经营，提高杨树人工林的经济效益，采用标准木法对洞庭湖区杨树人工林中不同径阶林木生物量进行了测定。结果表明：7年生杨树人工林的径阶集中分布在14～20 cm。不同径阶杨树单株不同器官生物量均遵循树干＞树枝＞树根（含桩）＞树皮＞树叶的分配规律；随着径阶的增长，树干在单株、林分内所占的比例均呈增长趋势；小于5 cm 的主干、树枝和根的生物量与地上部分的胸径和树高均成幂函数关系，相关系数分别为0．8394、0．9405和0．9947。

In order to realize the classification of populus plantation management,improve the economic benefits of pop-ulus plantations,using the standard wood method of Dongting Lake on artificial order different diameter trees in the forest biomass was determined.Results show that the trees diameter distribution of seven-year-old of populus plantation is con-centrated in the order of 14 cm to 20 cm.Different size order different organ biomass per plant populus are trunk 〉bran-ches 〉roots （including pile） 〉bark 〉distribution regularity of leaves.Trunk diameter with the increase of tree age, stage of growth within the plant,plantation proportion showed a trend of increase.Less than 5 cm of the trunk,branches and aerial parts of the root biomass and a power function relationship with diameter at breast height and tree height,the correlation coefficient was 0.839 4,0.940 5 and 0.994 7,respectively.