大熊猫（Ailuropoda melanoleuca）作为中国自然保护的旗舰物种，对大熊猫的保护取得了巨大的成就，但野生大熊猫保护仍然面临很多挑战。由于过去森林砍伐等原因，大熊猫现有栖息地的质量参差不齐，有些栖息地处于退化状态。基于此，本研究在四川大相岭山系，依据林冠郁闭度、林下竹林密度特点，选择了大熊猫的三种退化栖息地——竹子纯林区（八月竹Chimonobambusa szechuanensis ）、低郁闭度森林区（林下为冷箭竹 Bashania fangiana）以及人工纯林区（林下为三月竹 Qiongzhuea opienensis）开展试验，探索栖息地修复的方式。

本研究分别在竹子纯林区针对八月竹进行均匀、带状以及块状疏伐三种处理；在低郁闭度森林区针对冷箭竹进行带状和块状疏伐两种处理；在人工纯林区针对三月竹分布的林冠层以及林下灌木进行清理。连续两年对这些区域进行监测。

研究发现疏伐处理后，能够显著提高该区域当年竹子发笋率，同时促进一年生竹子生长。对于不同类型的竹种（八月竹和冷箭竹），相同强度的疏伐对成竹以及发笋量的影响不同。对林冠以及林下灌丛进行清理能促进取食竹更新。取食竹的发笋量会随着乔木郁闭度增加而降低，乔木郁闭度能够调控竹子种群密度。通过人工干预林冠层，改变乔木郁闭度对林下竹子进行管理在理论上可行。

三种竹子成竹基径与株高存在严格的线性关系，若结合生物量、以及竹子中的营养信息，此指标未来可应用于竹子质量的快速评估中。

利用围栏陷阱调查发现在大熊猫的三种退化栖息地内采取的人工干预措施对野生小型脊椎动物多样性没有影响。

基于本研究，对于三种不同类型的退化栖息地提出以下三种恢复方式：

1）纯竹林区域：对竹子进行带状疏伐处理，同时在疏伐带中补栽乔木，间隔2年左右重新疏伐，并抚育乔木，促进乔木生长以提高恢复区域内林冠层郁闭度。

2）低郁闭度森林区域：对林下竹子进行带状疏伐处理，同时在疏伐带中补栽乔木，间隔2年左右重新疏伐，定期对乔木进行抚育，促进乔木生长，进一步提高区域内林冠层郁闭度。

3）高郁闭度人工林区域：对乔木层以及林下灌丛进行清理，每年的发笋期前都应该进行林下灌丛清理，促进林下竹子种群的恢复。 

As the flagship species of Chinese nature conservation, the Giant panda (Ailuropoda melanoleuca) protection has made remarkable achievements in China. However, wild panda protection still faces many challenges. Due to past deforestation and other reasons, the quality of the giant panda's existing habitat is uneven, and some habitats are degraded. This study selected three degraded habitats for giant pandas in the Daxiangling Mountains of Sichuan, based on the canopy density and the density of understory bamboo forests-pure bamboo forest areas (The understory bamboo is Chimonobambusa szechuanensis), low canopy closure forest areas (The understory bamboo is Bashania fangiana), and pure artificial forests (The understory bamboo is Qiongzhuea opienensis). The district conducts experiments to explore ways of habitat restoration.

This study carried out three treatments of uniform, strip and block thinning of C. szechuanensis in the bamboo forest area; in the low canopy forest area, two treatments are carried out for the strip, and block thinning of B. fangiana; Clean up the forest canopy and understory shrubs in the artificial forest area. These areas have been monitored for two consecutive years.

We found that the thinning treatment can significantly increase the shooting rate of bamboo and promote the growth of annual bamboo. For different bamboo species (C. szechuanensis and B. fangiana), thinning of the same intensity has different effects on bamboo growth and shoot growth. Cleaning up the canopy and understory shrubs can promote the regeneration of bamboo. The number of bamboo shoots will decrease with the increase of the tree canopy closure, and the tree canopy density can regulate the density of the bamboo population. It is theoretically feasible to manage understory bamboo by artificially intervening the forest canopy and changing the canopy density of trees.

There is a strictly linear relationship between the base diameter of the three kinds of bamboos and the plant height. It can be combined with biomass and nutritional information in bamboo. This indicator can be used in the rapid assessment of bamboo quality in the future.

Investigations using fences and traps found that artificial interventions in the three degraded habitats of giant pandas had no effect on the diversity of small vertebrate wildlife.

Based on this research, the following three restoration methods are proposed for three different types of degraded habitats:

(1) Bamboo forest area: Thin the bamboo by using strip thinning. Replant the trees in the thinning belt at the same time. Re-thinning at an interval of 2 years and tending the trees to promote the growth of the trees and increase the canopy closure in the restoration area.

(2) Low canopy closure forest area: Thin the bamboo by using strip thinning. Replant the trees in the thinning belt at the same time. Re-thinning at an interval of 2 years and tending the trees to promote the growth of the trees and increase the canopy closure in the restoration area.

(3) Artificial forest area: Clean up the arbor layer and clean up the understory shrubs before the annual shoot period to promote the recovery of understory bamboo populations.