Liu Ying, Gong Chuangang, Pei Weihao, Fan Kaixuan, Shen Wenjing
School of Earth and Environment, Anhui University of Science and Technology, Huainan, China.
The Anhui Province Engineering Laboratory of Water and Soil Resources Comprehensive Utilization and Ecological Protection in High Groundwater Mining Area, Anhui University of Science and Technology, Huainan, China.
Front Plant Sci. 2024 Jan 15;14:1308209. doi: 10.3389/fpls.2023.1308209. eCollection 2023.
Root cutting caused by underground coal mining subsidence is among the leading causes of plant damage in western China. Detection of root cutting stress is of great importance in evaluating the degree of plant damage and changes in physiological conditions in underground coal mining disturbance conditions.
The present study assessed the use of chlorophyll fluorescence OJIP transient data to evaluate the disturbance characteristics of root cutting stress on leaf photosynthetic mechanisms in the typical shrub Krasch. Different root cutting ratios (10%, 20%, 30%, 50%, 75%, and 100%) were established on the roots of in the field, and the OJIP transient and JIP parameters of the leaves were measured.
The overall OJIP curves and each OJIP step in leaves decreased as the root cutting ratio increased, but the impact was relatively small for root cutting ratios of less than 30%. Through the analysis of JIP parameters and the established energy pipeline model, it was found that the energy capture efficiency and electron transfer efficiency of photosystem II decreased as the root cutting ratio increased. Therefore, we also inferred that the threshold for the plant root cutting ratio at which leaf photosynthetic mechanisms begin to change is 30-50%.
These results indicate that OJIP transient analysis can serve as a non-destructive, rapid technique for detecting plant root cutting stress in coal mining subsidence areas, which is of great value for non-destructive monitoring of plant root damage.
地下采煤沉陷导致的根系切断是中国西部植物受损的主要原因之一。在地下采煤扰动条件下，检测根系切断胁迫对于评估植物受损程度和生理状况变化具有重要意义。
本研究评估了利用叶绿素荧光OJIP瞬态数据来评价典型灌木柠条锦鸡儿根系切断胁迫对叶片光合机制的扰动特征。在田间对柠条锦鸡儿根系设置不同的根系切断比例（10%、20%、30%、50%、75%和100%），并测定叶片的OJIP瞬态和JIP参数。
随着根系切断比例的增加，叶片的总体OJIP曲线及各OJIP步骤均下降，但根系切断比例小于30%时影响相对较小。通过对JIP参数及所建立的能量管道模型分析发现，随着根系切断比例的增加，光系统II的能量捕获效率和电子传递效率降低。因此，我们还推断叶片光合机制开始变化的植物根系切断比例阈值为30%-50%。
这些结果表明，OJIP瞬态分析可作为一种无损、快速检测采煤塌陷区植物根系切断胁迫的技术，对植物根系损伤的无损监测具有重要价值。
