东亚夏季风可显著影响中国季风区气候变化,但是季风区植被净初级生产力(NPP)对夏季风气候变化的响应机理尚不明确。利用大气—植被相互作用模型(AVIM2)模拟了中国季风区植被NPP,分析了其与夏季风指数的相关关系,探讨了其对夏季风变化的响应机理。研究发现,我国南、北方植被对夏季风强度变化的响应方式和机理并不相同。强夏季风年北方植被NPP增加,而南方植被NPP减少。东亚夏季风对中国华北平原植被生长季NPP的作用主要是通过影响该地降水量实现的;京、津、冀地区植被NPP受东亚夏季风带来的气温和降水量变化的叠加影响,因而成为北方对夏季风变化最敏感的区域。东亚夏季风对我国南方江苏、安徽、湖南、湖北、江西植被NPP的作用是通过影响太阳辐射实现的,强夏季风导致太阳辐射减弱,从而使各省植被NPP减少。南方沿海的浙江和福建,强季风年带来的弱太阳辐射和低温是该地植被NPP减少的原因。广东、台湾植被NPP则主要受强夏季风带来的低温影响。
The East Asian summer monsoon has a significant impact on climate change in the Chinese monsoon region, but the responses and mechanisms of the terrestrial net primary productivity (NPP) to summer monsoon climate change are still not clear. In this paper, an atmosphere-vegetation interaction model (AVIM2) is used to simulate the NPP in the Chinese monsoon region. The correlation between NPP and summer monsoon index is analyzed, and the response mechanisms of NPP to the variations of summer monsoon are discussed. It is found that the vegetation responses and mechanisms to the variations of the summer monsoon are very different in North China and South China. Corresponding to strong summer monsoon years, the NPP in North China increases, while the NPP in South China decreases. The East Asian summer monsoon can affect precipitation over the North China Plain during vegetation growing seasons, and thus also affects the local NPR Due to the superimposed effect of temperature and precipitation on NPP, Beijing, Tianjin, and Hebei become the most sensitive areas to the variations of the summer monsoon in the North China Plain region. During strong East Asian summer monsoon years, the NPP in South China decreases, and the main impact factors correlated to a strong East Asian summer monsoon are different: In Jiangsu, Anhui, Hubei, Hunan, and Jiangxi provinces, it is the reduced solar radiation; in Guangdong and Taiwan provinces, it is the lower temperature; and in Zhejiang and Fujian provinces, the major factor is the superimposed effect of reduced solar radiation and lower temperature.