沈阳东陵区油松栎林群落数量特征的研究

该文以沈阳市东陵区油松栎林群落为对象，分析了群落数量特征.结果表明，油松栎林群落共有种子植物161种，分属49科121属，区系组成丰富.在植物区系地理成分上，种的分布类型以温带性质居多，共143种，占总种数的88.82％，表明了群落植物区系组成的温带亲缘关系.在群落结构上，油松栎林群落以地面芽植物最多，占36.02％.群落可分为乔木层、灌木层和草本层3个层次.利用Ievins和MacArthus指数测算了群落10个木本植物的生态位宽度和生态位重叠，以榆树、山里红、油松和卫矛有较大的生态位宽度值，分别为0.519 3、0.491 6、0.481 7和0.459 4油松与其它树种种间具有较大的生态位重叠，它在群落中占有相当重要地位，稠李同其它树种间的生态位重叠值较小，形成了局部小生境地段的优势种；种间联结性以山里红与黄菠萝呈显著正关联外，其它种对联结性都较低. 

Quantitative characteristics of Pinus tabulaeformis and Quercus mongolica community in Dongling District of Shenyang, northeast China

The quantitative characteristics of community of Pinus tabulaeformis and Quercus mongolica distributed in Dongling District,northeast China's Shenyang City were investigated.The results show that there are 161 seed plants classified in to 49 families and 121 genera.A close relationship between this community and the temperate flora is approved because 143 seed plants,which occupy 88.82% of the total,belong to the temperate biome.With regards to the structural feature of the community,hemicryptophyte occupies 36.02% of the total and dominates the community,and its vertical structure is composed of three layers:arbor layer,shrub layer and herb layer.Niche breadths and overlaps of 10 woody plant species were calculated by the Equations of Ievins niche breadth and MacArthus niche overlap. The results indicate that Ulmus pumila,Crataegus pinnatifida,P.tabulaeformis and Euonymus alatus have high niche breadth,which are 0.519 3,0.491 6,0.481 7 and 0.459 4 respectively,and P.tabulaeformis shows its importance by a higher niche breadth value and the highest niche overlap value.On the contrary,Prunus padus has the lowest niche overlap and usually acts as dominant species in some special microhabitats.Only Crataegus pinnatifida and Phellodendro amurense show a significantly positive interspecific relationship,while other pairs of species have a highly negative interspecific relationship.