气候－森林响应过程敏感性的初步研究──以四川西部紫果云杉群落为例

RESEARCH ON SENSITIVITY OF SUCCESSION PROCESSES OF FOREST FORMATION RESPONSED TO CLIMATE CHANGE──A CASE STUDY OF PICEA PURPUREA LOCATED IN THE WESTERN PART OF SICHUAN PROVINCE

本文以我国西部特有树种之一，紫果云杉（Ｐｉｃｅａｐｕｒｐｕｒｅａ）为例，采用林窗模型（ＦＯＲＥＣ），初步探讨了气候对森林群落的组成结构及生物量的影响。敏感性分析表明：（１）林窗模型对紫果云杉的林分结构以及演替过程的模拟与实际状况基本吻合；（２）森林群落对气候变化的响应是十分敏感的，并主要体现在气候基准和变率两个特征指标上。

In this study, we take the particular species of forest──Picea purpurea as an example to investigate the sensitivities of climate-forest response process using FOREC model. Thus we can evaluate the performance of our model.(1) Under climatological mean condition without annual change, from the beginning to 200th years, the competition among species is very intensive so that Picea purpurea, Picea asperata and Larix potaninii etc. formdominant species, constituting evergreen and deciduous broadleaf mixed forests, which is in reasonableagreement with observation and field investigation.(2) Under climatological mean condition with randomly annual changes, affected by the intensive climatechange, Picea purpurea community is in dynamic succession process from start to end. In the succession processBetula albo-siensis and Populus dovidiana firstly become pioneer species, then picea purpurea and Piceaasperata develop and grow, sometimes with continuously updating potential for PiCea pumurea. The respondingtime of Picea purpurea community to the intensive climate change is about 20～40 years, during which period thestructure and biomass of Picea purpurea also change dramatically.(3) Under climatological mean condition with periodic annual change, the periodic changes in climatebackground produce substantially periodic changes in the succession of Picea purpurea community. Piceapurpurea, Picea asperata and Betula albo-siensis are still the dominant species. However, in the composition offorest the propotion of Picea asperata is sometimes larger than Picea purpurea, which does not occur in the abovetwo experiments, indicating that climate change can have influence not only on the biomass of community butalso on the change of structure of foreSt in the community.In a word, the forest gap model (FOREC) can well reproduced the composition of foreSt stand of PiceQpurpurea and its succession, which is in reasonable agreement with observation, indicating that the model ispracticable in the study of forest community.