六个杨树无性系苗木生长、生物量和光合作用的研究*

六个杨树无性系苗木（２年生根１年生于）叶面积、苗高和地径的季生长用Ｒｉｃｈａｒｄｓ方程模拟，根据模拟参数分别计算最大绝对生长速率，平均绝对生长速率，生长期和拐点。结果为：六个无性系之间在生长速率、拐点和生长期方面均有明显的差异；最好的欧美杨６４号生长季末的总生物量是赤峰杨３４号的六倍多；六个无性系的总生物量与它们的总叶面积、平均单个叶片的面积、叶面积的平均生长速率和每株树的日净光合总量等呈正相关，而与单位叶面积的日净光合总量呈负相关；总生物量生产依赖于叶面积、苗高、直径的生长速率及其生长期。

Comparison of Growth,Biomass and Photosynthesis among Six Poplar Clones in Cold Semi-arid Area of Northeast China

The seasonal growth of leaf area,height and diameter in six poplar clones(one-year old shoot/two-year old root)in 1993 was simulated with Richard function.The absolute growth rate,mean absolute growth rate,duration of growth and the point of inflexion were calculated using the parameters in the fitted functions respectively.There were significant differences among the six clones in growth rate,point of inflexion and duration of growth.A more than sixfold difference was found between the total biomass production of the best introduced clone Populus×euramericana cl.'N3106'and that of the worst native clone Populus simonii×P.pyramidalis cv.'Chifengensis 34'.There is a linear correlations between the total biomass productions of these six clones with their total leaf area,individualleaf area,mean AGR of leaf area,and daily total net photosynthesis per tree,but a negative correlation with daily total net photosynthesis per unit leaf area.The high biomass production depends on the growth rate of leaf area,height and diameter,and the duration of growth.