中文摘要：

综述长江上游退化天然林的干扰体系、退化特征及恢复重建的研究现状，分析长江上游退化天然林恢复重建面临的主要问题，基于生态恢复重建的理论基础，阐述并拓展封山育林的传统概念。退化天然林恢复重建的基本对策是：依据自然演替的规律，仿拟天然老龄林的物种组成和群落结构，充分利用和启动自然调节机制，并根据自然演替的关键环节采用功能群替代或目的物种导人等辅助的人工措施，促进土壤和群落功能的修复，跨越或缩短某些演替阶段，加快恢复演替进程，尽可能利用乡土树种定向恢复以大径级、高经济价值林木为目标的森林群落。根据长江上游退化天然林的现状、类型及其特点，提出4种恢复重建的组合模式：1）封禁保护原始老龄林；2）封育重建严重退化生境；3）封育调整天然次生林群落结构与定向恢复调控；4）封育改造低效人工纯林。

英文摘要：

This paper reviewed past research works and current research progress regarding disturbance regime, degradation and restoration status, and analyzed the following key issues on restoration and reconstruction of the degraded natural forests on the upper reaches of Yangtze River. By integrating the classical and basic ecological theoretical rules into restoration and reconstruction practice, the Chinese traditional concept of ＂closing hills for forest conservation＂ was replenished with some new meanings. The restoration and reconstruction strategies of degraded natural forests were as follows： based on the law of natural succession imitating the species composition and community structure of the old-growth, making full use of the natural driving force of spontaneous succession, and taking rational assistant measures timely to introduce appropriate key species at a critical successional stage. As a result, the degradation process can be reversed, or a given succession stage can skip or shorten, and therefore, the restoration process and reestablishing sound structure and function of the degraded natural forests can be accelerated. Indigenous species are encouraged to be used for species introduction when appropriate as assistant measure. The following four rehabilitation and restoration models were proposed. 1 ） Protecting the old growth, primitive natural forest strictly for conserving gene bank and biodiversity and model stands; 2） For badly degraded sites where natural forest are totally lost, human- assisted measures must be taken to restore the habitat environments in terms of soil functions and re-establishing pioneer population; 3） For moderate degraded secondary naturally regenerated forest, appropriate human-assisted measures are needed to facilitate its natural succession process and to enhance its ecosystem services by regulating the species composition and community structure at the early successional stage; 4） For pure plantations, in particular, pure conifer plantation, dense canopy cover