庞泉沟地区山地杨桦林优势种种群格局与动态

POPULATION PATTERN AND DYNAMICS OF MOUNTAINOUS POPLAR-BIRCH FOREST IN PANGQUANGOU NATURAL RESERVE

森林群落的动态变化在各个阶段表现为优势种群数量增长和消亡及竞争强弱的变化,径级结构和格局分析能有效地描述这种变化的趋势.本文研究庞泉沟自然保护区山地杨桦林这种变化特征,结果表明群落变化过程中,一定尺度范围内的山杨、白桦、青杄在小尺度上均为集群分布,在大尺度上趋于随机分布.山杨和青杄呈明显正相关关系,占据相似的生境,青杄在竞争中占有优势,在演替过程中将取代山杨.白桦和红桦在群落变化过程中较为稳定,在演替中可能将长期存在,与青杄形成针-阔叶混交林.

Dynamic changes of forest communities in various stages are shown as the dominant population growth and demise and changes of competitive strength, this change trend can be effectively described by size structure and pattern analysis. The paper studies characteristics of dynamic change in the mountain poplar-birch in the Pangquangou National Nature Reserve. and results show that Populus tremula and Betula platyphylla and Picea zvilsonii are clumped within a certain scale, Populus trernula, and Picea zvilsonii occupy similar habitat. Picea voilsonii own notable advantage in the competition, and will replace Populus tremula in the succession. For population change in the community is relative stable Betula platyphylla and Betula albosinensis, long-presence, and possible form broadleaf-coniferous forest mixed forest together with Picea voilsonii.