珍稀濒危植物长白松(Pinus sylvestris var. sylvestriformis)天然种群生存压力

为了揭示珍稀濒危植物长白松（Pinus sylvestris var. sylvestriformis）天然种群生存压力状况，在全面调查长白山国家级自然保护区长白松分布的基础上，基于邻体干扰模型，引入树高、冠幅、方位等因子，提出3种生存压力指数：个体生存压力指数、种群生存压力指数和群落生存压力指数，分析天然长白松所处6种群落类型中的生存压力。结果表明：长白松承受群落生存压力（PI）从大到小依次为：白桦-臭冷杉群落（PI=21.532）、红松-长白松群落（PI=14.185）、白桦群落（PI=13.262）、臭冷杉-长白松群落（PI=8.752）、长白落叶松-鱼鳞云杉群落（PI=7.780）和蒙古栎群落（PI=5.440）。多重比较单向方差分析表明，6种群落类型中长白松生存压力总体上差异明显，白桦-臭冷杉群落中长白松生存压力最大，显著高于其他5种群落；竞争树种主要为长白落叶松、红松、长白松、山杨和白桦，这5个树种生存压力大小占群落生存压力的87%；红松-长白松群落和白桦群落中长白松生存压力无明显差异，但显著高于臭冷杉-长白松群落、长白落叶松-鱼鳞云杉群落和蒙古栎群落；臭冷杉-长白松群落、长白落叶松-鱼鳞云杉群落和蒙古栎群落中长白松生存压力相对较小，彼此无明显差异。长白松生存压力与其所处植物群落演替阶段及其龄级结构有关。目前，保护区采取严格保护和管理方式不完全有利于长白松种群的稳定发展。根据长白松种群所处的植物群落生境特点、种群生存压力状况并结合种群年龄结构特征，针对不同群落类型提出相应抚育措施建议以期为长白松天然种群的保护提供参考。

Survival pressure of a rare and endangered plant natural population of Pinus sylvestris var. Sylvestriformis

In order to reveal the rare and endangered plant Pinus sylvestris var. Sylvestriformis natural population survival pressure status, we made a comprehensive survey of distribution of Pinus sylvestris var. sylvestriformis population by setting up quadrats according to the altitude gradient in Changbai Mountain National Nature Reserve. We proposed three kinds of survival pressure index including individual survival pressure index, population survival pressure index and community survival pressure index to analyze the survival pressure of Pinus sylvestris var. Sylvestriformis in six types of plant communities. Ecological factors such as tree height, canopy width and tree azimuth were introduced into the pressure survival index based on neighborhood interference model. Results showed that the survival pressure of Pinus sylvestris var. Sylvestriformis presented obvious difference in six types of plant communities. The survival pressure from more to less in proper order were Betula platyphylla-Abies nephrolepis community, Pinus koraiensis-Pinus sylvestris var. sylvestriformis community, Betula platyphylla community, Abies nephrolepis-Pinus sylvestris var. Sylvestriformis community, Larix olgensis-Picea jezoensis community, and Quercus mongolica community. Multiple comparative one-way analysis of variance showed that there were significant differences in the survival pressure among the six communities. The survival pressure in Betula platyphylla-Abies nephrolepis community was the highest, which was significantly higher than that in other five communities. The main competitive species were Larix olgensis, Pinus koraiensis, Pinus sylvestris var. sylvestriformis, Populus davidiana, and Betula platyphylla, which accounted for 87% of the total community survival pressure of Pinus sylvestris var. Sylvestriformis. There was no significant difference in the survival pressure of Pinus koraiensis-Pinus sylvestris var. sylvestriformis community and Betula platyphylla community, but the survival pressure of Pinus koraiensis-Pinus sylvestris var. sylvestriformis community was significantly higher than that of Abies nephrolepis-Pinus sylvestris var. Sylvestriformis community, Larix olgensis-Picea jezoensis community, and Quercus mongolica community. Among the latter three communities, there was no significant difference in the survival pressure. Pinus sylvestris var. Sylvestriformis was a strongly heliophilous species, the survival pressure of Pinus sylvestris var. Sylvestriformis was related to the plant communities succession stage and age structure of Pinus sylvestris var. Sylvestriformis population. The strict protection and management in the Changbai Mountain Nature Reserve was not completely conducive to the stable development of the population of Pinus sylvestris var. Sylvestriformis. Finally, according to the characteristics of plant community habitat, population survival pressure and population age structure characteristics, we put forward the corresponding management measures for six types of plant communities to provide reference for the protection of the population of Pinus sylvestris var. Sylvestriformis.