摘要
为深入了解华北落叶松的光合生理生态特征,探究其光抑制现象的内在机理,本研究以河北省塞罕坝机械林场华北落叶松人工林为对象,利用Li⁃6400便携式光合仪,对不同轮层针叶持续强光照射,分析判断导致光抑制现象产生的主要限制因素,以及净光合速率(P_(n))与环境因子的关系。结果表明:在强光照射下,华北落叶松上层和中层针叶均发生光抑制现象,气孔限制值(L_(s))与胞间CO_(2)浓度(C_(i))变化趋势相反。上层和中层针叶P_(n)均与相对湿度(RH)呈显著相关(相关系数分别为0.720和0.934),与饱和水汽压差(VPD)和温度(T)存在显著相关性(相关系数分别为-0.850和-0.820);下层针叶P_(n)与RH、VPD和T也均呈显著相关,但与上层和中层针叶的相关性趋势相反。本研究表明,光抑制现象主要发生在树冠的上层和中层,RH、VPD、T是影响华北落叶松冠层P_(n)的主要环境因子,但上、中层针叶和下层针叶对环境因子的响应趋势存在明显差异,研究结果可为调控树冠结构、改善微环境、缓解冠层光抑制现象奠定基础。
To better understand the photosynthetic ecophysiological characteristics of Larix principis⁃rupprechtii and explore the mechanism of photoinhibition,we measured canopy photosynthetic indicators of Larix principis⁃ruppre⁃chtii plantation under intense irradiation using Li⁃6400 portable photosynthetic instrument,in Saihanba Mechanical Forest Farm of Hebei Province.We analyzed the main drivers of canopy photoinhibition and the relationships between net photosynthetic rate(P_(n))and environmental factors.The results showed that under intense irradiation condition,photoinhibition occurred in the upper and middle layers of canopy.The change trend of stomatal limit values(L_(s))was opposite to that of the intercellular CO_(2) concentration(C_(i)).The P_(n) in the upper and middle cano⁃py was positively correlated with relative humidity(RH)(with the correlation coefficients of 0.720 and 0.934,respectively),but negatively correlated with vapor pressure deficit(VPD)and temperature(T)(with the correla⁃tion coefficients of-0.850 and-0.820,respectively).The P_(n) in the lower canopy was significantly correlated with RH,VPD,and T,but their trends were opposite to upper and middle canopy.Our results indicated that the pho⁃toinhibition mainly occurred in the middle and upper canopy,with RH,VPD,and T as the main factors driving P_(n).The response patterns of P_(n) to environmental factors were significantly different among upper,middle and lower can⁃opy.The results lay a foundation for regulating canopy structure,improving the microenvironment,and mitigating canopy photoinhibition.
作者
周颖
高媛
赵浩然
郭忠诚
籍翠莹
杨陈
刘强
ZHOU Ying;GAO Yuan;ZHAO Haoran;GUO Zhongcheng;JI Cuiying;YANG Chen;LIU Qiang(Hebei Agricultural University,Baoding 071000,Hebei,China)
出处
《生态学杂志》
北大核心
2025年第2期383-388,共6页
Chinese Journal of Ecology
基金
国家自然科学基金项目(32201556)
河北农业大学引进人才科研专项(YJ201942)资助。
关键词
强光
气孔限制
非气孔限制
环境因子
strong light
stomatal limitation
non⁃stomatal limitation
environmental factor
