Photosynthetically active radiation dataset in Chinese Ecosystem Research Network (2005 – 2015)

Photosynthetically active radiation (PAR) plays important roles in multiple subjects such as ecology, agronomy and climatology. It is the fundamental physiological variable that reveals the exchange processes of material and energy. PAR is essential for studying the potential photosynthesis, potential yield and simulation of plant growth and soil carbon fixation. The daily average PAR dataset in 8 Chinese typical terrestrial ecosystems covers 40 radiation stations (which belong to Chinese Ecosystem Research Network, CERN) from 2005 to 2015. To ensure the reliability and comparability of observational data, centralized calibration and normative data quality control are conducted. Standard radiative lamp and spectrometer are used to establish quantum sensor calibration system and the accuracy of the calibrated quantum sensor is within 5% which meets the WMO criterion of photosynthetically active radiation study; then the quality control of PAR dataset is conducted using the extremum method.光合有效辐射（Photosynthetically Active Radiation，PAR）在生态学、农艺学与气候学等多个学科领域中发挥着关键作用，其是揭示物质与能量交换过程的基础生理变量。光合有效辐射是开展潜在光合作用、潜在产量研究以及植物生长与土壤固碳模拟的核心支撑要素。本数据集包含中国8类典型陆地生态系统的日平均光合有效辐射数据，覆盖2005年至2015年间隶属于中国生态系统研究网络（Chinese Ecosystem Research Network，CERN）的40个辐射观测站的观测资料。为保障观测数据的可靠性与可对比性，本数据集开展了集中校准与规范化数据质量控制工作：首先采用标准辐射灯与光谱仪构建量子传感器校准体系，经校准后的量子传感器精度可达5%以内，符合世界气象组织（World Meteorological Organization，WMO）在光合有效辐射研究领域的相关标准要求；随后采用极值法完成该数据集的质量控制流程。