【摘要】 本文采用分层切割法和壕沟全挖法对江苏省新沂市农田林网中，４年生主要的杨树无性系（Ｗ－４６杨，Ｉ－６９杨，ＮＬ－８０１０５杨和ＮＬ－８０２０５杨）的地上部分生物量以及根系生物量进行了测定和分析。结果表明，ＮＬ－８０２０５杨不仅平均单株的生物量最大，而且树干的形质优良。因此，在平原农田林网的经营中，选择ＮＬ－８０２０５杨，既可以提高营林的收益，又能够增强林网的防护效果。更多还原

【Abstract】 The above-ground proportion of the biomass and the root biomass of four type of poplar clones (W - 46, I - 69 NL - 80105 and NL - 80205 )have been measured by vertical stratifying method and trench digging method. Through the vertical biomass structure analysis,it is found out that the poplar clone,NL - 80205,is the greatest in stem fullness as well as in biomass among the four clones. Thus, choosing NL - 80205 poplar clone for cultivation will be able to either improve the profits of plain forestry management or enhance the protection effects of the forest metwork in the area.更多还原