文献类型：期刊文献

英文题名：The Effects of Long-Term Precipitation Exclusion on Leaf Photosynthetic Traits, Stomatal Conductance, and Water Use Efficiency in Phyllostachys edulis

作者：Cao, Yonghui[1] Li, Jianming[1,2] Li, Sheng[1] Zhou, Benzhi[1]

第一作者：曹永慧

通信作者：Li, S[1];Zhou, BZ[1]

机构：[1]Chinese Acad Forestry, Res Inst Subtrop Forestry, Fuyang 311400, Peoples R China;[2]Northeast Forestry Univ, Coll Forestry, Harbin 150040, Peoples R China

年份：2024

卷号：15

期号：5

外文期刊名：FORESTS

收录：;EI(收录号：20242216179194);Scopus(收录号：2-s2.0-85194251182);WOS:【SCI-EXPANDED(收录号:WOS:001232311100001)】；

基金：This study was supported by the project for P. edulis research and a grant from the Science and Technology Department of Zhejiang Province, China. This study was supported by CFERN&GENE award funds for ecological papers. The authors thank Qianjiangyuan Forest Ecosystem Research Station for their support of the field work.

语种：英文

外文关键词：Phyllostachys edulis (Carri & egrave;re) J. Houz.; photosynthetic parameters; stomatal conductance; leaf water use efficiency; light intensity; vapor pressure deficit; precipitation exclusion

摘要：Ongoing climate change is projected to intensify drought stress globally. Understanding the response mechanisms of Phyllostachys edulis (Carri & egrave;re) J. Houz. (moso bamboo) to long-term drought is crucial, given its significance as a carbon sequestration resource. In this study, precipitation exclusion was implemented to simulate drought stress and we investigated the effects of long-term drought on the photosynthetic parameters, stomatal conductance, and water use efficiency of moso bamboo. The results showed that throughout all growth seasons, the maximum net photosynthetic rates (Pmax) of bamboo at all ages under long-term drought conditions (after 8 years of precipitation exclusion treatment) were significantly lower than those of the control (p < 0.05). It can be concluded that long-term drought reduced the maximum photosynthetic capacity of the bamboo at all ages. Under long-term drought conditions, there were many seasons where the light saturation point (LSP) of first-degree (1-2 years old) bamboo and third-degree (5-6 years old) bamboo under drought was significantly lower than those of the control, while the LSP value of second-degree (3-4 years old) bamboo under drought was significantly higher than that of the control. This suggests that long-term drought reduced the ability of first-degree and third-degree bamboo to utilize strong light, while improving the ability of second-degree bamboo to utilize strong light in summer, autumn, and winter. Under long-term drought conditions, the light compensation point (LCP) and the apparent quantum efficiency (AQY) of the bamboo decreased. It can be concluded that long-term drought reduced the ability of first-degree bamboo to utilize weak light in all seasons, as well as the ability of second-degree bamboo to utilize weak light in spring and autumn; meanwhile, it improved the ability of second-degree bamboo to utilize weak light in summer and winter, and the ability of third-degree bamboo to utilize weak light in spring, summer, and autumn. In the high light range (PARi > 1000 mu mol m-2 s-1), there were significant differences in stomatal conductance (gs) among different the different treatments of bamboo, which were influenced by both the growing season and the forest age. Compared to the control, under drought conditions, the stomatal conductance of third-degree bamboo increased in spring and that of the second-degree bamboo increased in autumn. The correlation analysis showed that the relationship between the stomatal conductance and vapor pressure deficit (VPDL) of bamboo under long-term drought conditions showed a significant polynomial relationship in both high and low light ranges. The correlation between the instantaneous water use efficiency (iWUE) and VPDL for the drought and control treatments of bamboo also showed a significant polynomial relationship in high light ranges. It was found that long-term drought changed the photosynthetic parameters of the bamboo, reflecting its ability to tolerate and adapt to drought in different seasons. Age-related differences in photosynthetic parameters should be fully considered in forest age structure adjustments and forest thinning procedures to strengthen the light intensity and maintain the opening of the stoma. These results provide a theoretical basis for the efficient and sustainable cultivation of bamboo under global climate change.