Abstract: Herbaceous plants of the genus Chenopodium are common weeds in China,characterized by their high pollen production,prolonged dispersal period,and strong allergenicity,which pose risks to atmospheric environmental quality and human health. Especially under the context of climate change and policies of converting farmland back to forest and grassland,the risk of allergies increases. To accurately forecast the onset of flowering of Chenopodium weeds,this study utilized flowering initiation data from 52 stations across Northern China from 1981 to 2018. It constructed five phenological process models driven by daily sequences of temperature,precipitation,and photoperiod,with subsequent calibration and selection of parameters. The results showed that temperature was the dominant environmental factor to influence the onset of flowering,and photoperiod also played a significant regulatory role,while the impact of chilling on the flowering period of four types of mature Chenopodium weeds was not significant. Moreover,in arid regions,it was necessary to consider precipitation factors in forecasting the onset of flowering for Chenopodium weeds,as drought conditions tended to delay the flowering period,whereas precipitation had a facilitating effect. This research serves as a supplementary tool for forecasting the pollen season of Chenopodium weeds in Northern China,aiding in the prevention and treatment of allergies caused by Chenopodium pollen.

Key words: Chenopodium, Flowering forecast, Phenological models, Drought, Photoperiod

摘要： 藜属(Chenopodium)草本植物是我国常见杂草，其花粉量大，持续时间长，致敏性强，对大气环境质量和人类健康都有一定危害，尤其在气候变化和退耕还林还草背景下，致敏风险增加。为精准预报藜属杂草始花期，本文基于中国北方地区1981—2018年52个站点的藜属杂草始花期实测数据，构建了5种基于逐日气温、降水、光周期序列驱动的物候过程模型，并进行了参数率定和优选。结果表明，温度是主导始花期的环境因子，光周期也起着重要的调控作用，而冷激对4种熟型藜属杂草始花期的影响并不显著。此外在干旱区考虑降水因子进行藜属杂草始花期预报是有必要的，干旱会延迟藜属杂草始花期，而降水则能起到一定的促进作用。本研究可作为我国北方地区藜属杂草花粉花期预报的辅助手段，为防治藜属杂草花粉过敏提供帮助。

关键词: 藜属, 花期预报, 物候模型, 干旱, 光周期