改则地区气候变化对植被生理过程的影响及反馈效应的模拟研究

Simulation of Influence of Climate Change on Vegetation Physiological Process and Feedback Effect in Gaize Region

利用1997年10月1日至1998年9月30日设置在青藏高原西部改则的自动气象站观测资料作为强迫场,采用大气-植被相互作用模式(AVIM)对改则地区气候变化对植被生长过程的影响及反馈效应进行了模拟研究。结果表明,AVIM模式对青藏高原西部陆面过程具有一定模拟能力,能够较真实地模拟出地表特征量的变化特点。通过敏感性试验发现,青藏高原气候变化对植被生理生长过程有明显影响:降水增加有利于植被生长,尤其在雨季最为明显,其他季节无太大变化;气候变暖对植被生理过程的综合作用是植被净光合作用的变化,即春季增强,夏季减弱,秋季和冬季变化不大;"暖湿化"对高原植被生态系统的影响主要是春季和夏季植被活动增强,尤其春季最为明显。植被物理特性参数可以在相当大程度上改变陆面过程,进而导致高原热源发生变化,因此,为准确估计地表能量收支,对模式陆面参数进行深入研究是必要的。

Using the automatic weather station data obtained from-western-Tibetan Plateau-and the Atmosphere-Vegetation Interaction Model （AVIM）,the influence-of climate change on vegetation physiological process and feedback effect in Gaize are analyzed.The results may lead to the following conclusions that AVIM model can-reasonably simulate the change trends of land surface characteristic over-thewestern Tibetan-Plateau.The climate change over Tibetan Plateau has significantly influence-on-vegetation physiological process： More precipitation lead the-more strength of vegetation growth,it is obvious in rainy season,but not in other seasons;climate warming can change the vegetation physiological process.The vegetation activity enhances in spring and weakens in summer-and unobvious in autumn and winter.Vegetation physical properties can affect-the-land surface process,which led to the Plateau-surface heat source change.Therefore,in order to accurately estimate the surface energy budget,the further research-on land surface parameters in-the model is necessary.