运用Hegyi单木竞争指数分析了内蒙古红花尔基自然保护区天然樟子松(Pinus sylvestrisvar. Mongolica Litv.)林内所有胸径大于2 cm的樟子松、山杨(Populus davidiana Dode.)、白桦(Betula platyphylla Suk.)和山荆子(Malus baccata L.)的种内和种间竞争强度。结果表明,样地中主要的竞争木和对象木均为樟子松和白桦;樟子松的种内竞争强度(0.534)远大于种间竞争强度。随径级的增大,樟子松的种内竞争强度逐渐减小,且与胸径存在幂函数关系CI=A.D-B。胸径达到30 cm后,樟子松种内竞争强度变化不明显。作为竞争木,樟子松对其他树种产生了较大的竞争压力。

The intraspecific and interspecific competition intensities of Pinus sylvestris var. mongolica Litv., Populus davidiana Dode., Betula platyphylla Suk.and Malus baccata L.(withDBH> 2cm)in P. sylvestris var. mongolica natural forest in Honghuaerji Nature Reserve of Inner Mongolia were analyzed by the Hegyi's single tree competition index. The results showed that the dominant competitive and objective trees were both of P. sylvestris var. mongolica and B. platyphyllain the plot. The intraspecific competition intensity of P. sylvestris var. mongolica(0. 534) was much higher than the interspecific competition intensity. The intraspecific competition intensity of P. sylvestris var. mongolica declined gradually with the DBH class increased. There was a power function relationship CI=A·D –B between the in traspecific competition intensity and the DBH of P.  sylvestris var. mongolica, and the change of competition intensity was not obvious when the DBH above 30cm. The competitive trees of P. sylvestris var.  mongolica had a heavy competition pressure on the other tree species.