摘要：Abstract Photosynthesis in Amazon rainforests is essential to the carbon and water cycle on a global scale, but its seasonal dynamics remain less understood. Using clear sky satellite products combined with in situ ground observations, we investigated the seasonal dynamics of photosynthesis in this unique region as well as the contribution of moisture to these dynamics. We confirmed the unique dry season increase in photosynthesis for most parts of the study region as well as small positive photosynthetic anomalies in relatively dryer years, such as El Niño years. Taking into account the contribution of increased light and new leaf flushing in dry seasons to the seasonal dynamics of photosynthesis, we found significant negative correlations between moisture variables (especially soil moisture) and photosynthesis in Amazon rainforests, especially for humid ecosystems such as primary moist forests and for humid periods such as wet seasons. Excessive moisture contributes to the seasonal dynamics of photosynthesis by changing the value of the peak and the position of the minimum values, but this process was not well‐documented in previous studies. Our study highlights the need to consider the negative impacts of excessive moisture on photosynthesis in wet ecosystems, and further research is required to support the determination of future changes in photosynthesis in different regions.
