皇藏峪国家自然保护区青檀种群年龄结构及种内、种间竞争

青檀(Pteroceltis tatarinowii)是一种具有重要经济和保护价值的树种。本文研究了安徽省皇藏峪国家级自然保护区青檀种群的年龄结构,并利用Hegyi单木竞争指数模型研究该地区青檀的种内、种间关系。结果表明:皇藏峪自然保护区青檀种内、种间竞争关系最合适的样圆半径为8m。保护区青檀种间竞争指数占青檀所受总竞争指数的71.79%,种内竞争指数占28.21%,该地区青檀所受的竞争压力主要来自于种间;不同竞争木的竞争指数表明:使青檀受压的主要植物是栓皮栎和黄连木。受压最大的青檀是胸径在2～5cm的小树,而随着青檀径级的增大,植株所受竞争强度逐渐减小,竞争强度与胸径的关系服从幂函数关系。根据幂函数模型预测,在青檀胸径达15cm之前,受到的竞争压力较大,此后,竞争压力变小。

Age Structure and Inter- and Intra- Species Competition of Pteroceltis tatarinowii in Huangcangyu Natural Reserve

The age structure of Pteroceltis tatarinowii in Anhui Huangcangyu Natural Reserve was studied by space substituting time,and the inter-and intra-species competition intensity in P.tatarinowii was quantitatively analyzed by Hegyi single-tree competition index model.The results showed that 8 m was defined the zone of the intra-and inter-competition relationships of P.tatarinowii.The inter-competition intensity accounts for 71.79% of the total competition intensity in P.tatarinowii,and intra-competition intensity accounts for 28.21%,thus the inter-competition stress was far more intensity than intra-competition,and the competition mainly came from two competitors:Quercus variabilis and Pistacia chinensis.The stress was most intense in diameter of the objective trees between 2～5 cm,and the competition intensity in P.tatarinowii decreased gradually with increasing tree diameter.The relationship of the DBH of objective tree and the competition intensity between competitive tree and objective tree in the whole forest and P.tatarinowii population nearly conformed to power function.The model predicted that the stress was more intense before the tree grows to 15 cm in DBH,after that,it will decline.