【摘要】 根据陕北黄龙林区辽东栎群落30个样地资料,通过聚类对该群落进行了类型划分,共划分为6个群丛,分别为A.辽东栎(Quercus liaotungensis)-土庄绣线菊(Spiraea pubescens)、B.辽东栎-虎榛子(Ostryopsis davidiana)、C.辽东栎-胡枝子(Lespedeza bicolor)、D.辽东栎-水栒子(Cotoneasten multtflorus)、E.辽东栎-白刺花(Sophora viciifolia)、F.辽东栎-黄蔷薇(Rosa hugonis)。另外,对各类型辽东栎林和不同坡向辽东栎群落的生物多样性进行了计算,结果表明各群落Whittaker多样性指数存在明显的差异,并与其所处的生境条件密切相关,其中与坡向关系较大,即北坡>西北坡>东南坡>西南坡>南坡。最后,对辽东栎林乔木层和灌木层组成种类生态位和生态位重叠进行了计算分析,结果表明,乔木层,辽东栎、油松、白桦不仅生态位宽度较大(LB值1.2~1.5),而且三者之间的生态位重叠值也较大(Oik值0.7~0.9);在现演替阶段它们之间存在着较为激烈的资源利用性竞争;灌木层,土庄绣线菊、榛子、铁杆蒿、黄蔷薇生态位宽度较大(LB>1),而葱皮忍冬、南蛇藤、鼠李、鞘柄菝葜较小(LB为0.4~0.45);生态位重叠值>0.8的种对仅占灌木计算种对的2.8%,而<0.6的种对占87.4%。更多还原

【Abstract】 Based on data of 30 plots from Huanglong Mts. in Northern Shaanxi, Quercus liaotungensis communities(QLC) were classified into six associations by clustering method, namely A. Quercus liaotungensis-Spiraea pubescens;B. Q. liaotungensis-Ostryopsis davidiana;C. Q. liaotungensis-Lespedeza bicolor;D. Q. liaotungensis—Cotoneaster multtflorus;E. Q. liaotungensis-Sophora viciifolia;F. Q. liaotungensis-Rosa hugonis. Additionally, calculation of the species diversity of different QLC and QLC on different slopes indicates that Whittaker diversity indices differentiate obviously among communities and relate closely with their habitats, especially the slope exposure , N>NW>ES>WS>S. Calculation and analysis of niche breadth and niche overlaps of the species in arbor and shrub layers of QLC show that in arbor layer, Quercus liaotungensis, Pinus tabulaeformis and Betula platyphylla are not only bigger in niche breadth (LB 1.2-1.5)but also are greater in niche overlap(Oik 0.7-0.9), and that strong competition exist among them in current succession stage; in shrub layer, the niche breadths of Spiraea pubescens,Corylus heterophylla, Atermisia sacrorum, Rosa hugonis are bigger (LB>1) than others, but that of Lonicera ferdinandii, Celastrus orbiculatus,Rhamnus davurica, Smilax stans is smaller (LB 0.4-0.45).The species pairs with Oik >0.8 account for only 2.8% of all shrub species pairs, but those pairs with Oik >0.6 take up 87.4%.更多还原