Abstract Phenology is an important indicator of the biological responses to climate change, and previous studies have reported divergent phenological responses of grasslands in Inner Mongolia from the analyses of in-situ measurements and satellite observations; thus, robust phenology models are required to understand and simulate the relationship between ecosystems and climate change. However, phenology models for natural grasslands in which heating accumulation, chilling requirements, precipitation effects and other climate factors are introduced at the same time are relatively deficient; as a result, the accuracy of the herbaceous plant phenology model and its universality across different species and regions are restricted. We proposed an improved phenology model (unified model combined with precipitation driving, UMPD) that reflects the combined effect of temperature and precipitation at the forcing unit level. Green-up evaluation based on satellite observations shows that the UMPD phenology model achieves better accuracy than previous models (RMSE

中文翻译：

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1962-2017年内蒙古羊草草原绿化期变化监测的改进物候模型

摘要 物候是生物对气候变化响应的重要指标，前人的研究报道了内蒙古草原的不同物候响应，从现场测量和卫星观测的分析来看；因此，需要强大的物候模型来理解和模拟生态系统与气候变化之间的关系。但同时引入蓄热、冷量、降水效应等气候因素的天然草原物候模型相对不足；因此，草本植物物候模型的准确性及其在不同物种和地区之间的普遍性受到限制。我们提出了一种改进的物候模型（统一模型结合降水驱动，UMPD)，反映了强迫单位水平上温度和降水的综合影响。基于卫星观测的绿化评估表明 UMPD 物候模型比以前的模型（RMSE