• 研究报告 •

### 逐步失水过程中绿竹光响应进程及其拟合

1. 1中国林业科学研究院亚热带林业研究所, 杭州 311400;
2福建省永安林业(集团)股份有限公司, 福建永安 366000
• 收稿日期:2018-09-19 出版日期:2019-06-15 发布日期:2019-06-15
• 通讯作者: * E-mail: jzhxie@163.net
• 作者简介:杜澜,男, 1994年生,硕士研究生. 主要从事竹林生态学研究. E-mail: dulan1027@163.com
• 基金资助:

### Light response process and simulation of Dendrocalamopsis oldhami in the process of gradual water loss.

DU Lan1, XIA Jie1, LI Hai-hua2, WU Wei2, CHEN Liang1, ZHANG Wei1, CHEN Sheng1, XIE Jin-zhong1,*

1. 1Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China;
2Nursery Center of Yongan Forestry (Group) Incorporated Company, Yong’an 366000, Fujian, China
• Received:2018-09-19 Online:2019-06-15 Published:2019-06-15
• Supported by:
This work was supported by the National Key R&D Program of China (2016YFD060090104), the National Science & Technology Project in Rural Area of China (2015BAD04B01-5), and the Science & Technology Aid Project for Developing Countries (KY201502001

Abstract: The photosynthesis response of the leaves of 2-year-old potted Dendrocalamopsis oldhami seedlings under continuous and multistage soil moisture was measured and analyzed by using a porta-ble photosynthetic system (Li-6400) during the natural water consumption process from artificial watering to saturated soil water. The results showed that there was less obvious photoinhibition in leaves of D. oldhami grown in the region where the relative soil water content (SRWC) was from 53.5% to 95.6%. There was a higher net photosynthetic rate in relative water deficit environment with the relative soil water content from 53.5% to 69.6%. When SRWC was below 33.6%, there was a significant photoinhibition. When the relative soil water changed, the Pn max value simulated by rectangular hyperbola model was much higher than measured value. The simulated light saturation point (LSP) value fitted by the rectangular hyperbola model, the non-rectangular hyperbola model and the exponential model was much lower than the measured value, and the simulation of the light-response curve under extreme water shortage conditions had larger differences between the fitted values and the observed data. Both the stomatal limitation value (Ls) and water use efficiency (WUEinst) showed a similar response process as the relative soil water decreased. Both of them increased first and then decreased, with the maximum value appeared in the range of 53.5%≤SRWC≤69.6%. Such a result showed a similarity and representative with the Pn max of photosynthesis light-response processes under changing soil moisture. The optimal humidity management range of SRWC for normal photosynthesis in leaves of D. oldhami was from 53.5% to 69.6%. In addition, it had good adaptability to higher soil water content (69.6%≤SRWC≤95.6%). Rectangular hyperbola modified model could well simulate the light-response of photosynthesis under different soil water conditions (23.1%≤SRWC≤95.6%), while the other three models had their own limitations.