Abstract: It is very important for sustainable utilization of grassland to study the impact of climate change on grassland productivity based on grassland ecosystem model. In this paper,Shiqu (32.98° N,98.10° E) and Ruoergai (33.58° N,102.97° E) were selected as representative sites in Northwest plateau of Sichuan province. The long-term observation data of grassland biomass from the livestock meteorological experiment stations were used to calibrate and validate the grassland ecosystem model (CENTURY). The results showed that there was a close consistency between the simulated and measured above-ground biomass at Shiqu and Ruoergai. The determination coefficients were 0.85 and 0.45 (P<0.05). Relative mean square roots were 5.4 g·m^-2 and 122.4 g·m^-2. The CENTURY model could be used to simulate pasture above-ground biomass and thereafter study the impact of climate change on grass productivity in Northwest plateau of Sichuan province. The changes of grassland above-ground biomass at Shiqu and Ruoergai were simulated during the past 57 years (1961-2017) based on CENTURY model. The simulation results displayed that the grassland above-ground biomass during the past 57 years increased significantly at Shiqu and Ruoergai,and the increasing rates were 5.4 g·m^-2·(10a)^-1 and 17.2 g·m^-2·(10a)^-1,respectively.

Key words: CENTURY model, Suitability, Validation, Northwest plateau of Sichuan province, Grassland

摘要： 利用草地生态模型评价气候变化对草地生产力的影响，对于草地的可持续利用有重要意义。本文选取川西北高原的石渠和若尔盖为代表站点，基于试验站多年牧草观测资料，对草地生态系统模型（CENTURY）在川西北高原草地的适用性进行研究。结果表明：CENTURY模型模拟的石渠和若尔盖牧草地上部生物量的模拟值与观测值比较吻合，决定系数分别为0.85和0.48，均通过了0.05的显著性检验，均方根误差分别为5.4 g·m^-2和122.4 g·m^-2，CENTURY模型能够较好的模拟牧草地上部生物量，适用于气候变化对川西北高原草地生产力的影响研究。基于验证后的CENTURY模型对1961-2017年牧草地上生物量的模拟结果显示，近57年来石渠和若尔盖牧草地上生物量均呈显著增加趋势，增加速率分别为5.4 g·m^-2·（10a）^-1和17.2 g·m^-2·（10a）^-1。

关键词: CENTURY模型, 适用性, 验证, 川西北高原, 草地