三江源植被净初级生产力估算研究进展（英文）

The Three-River Headwater Region(TRHR), known as the 'Water Tower of China', is an important ecological shelter for national security interests and regional sustainable development activities for many downstream regions in China and a number of Southeast Asian countries. The TRHR is a high-elevation, cold environment with a unique, but typical alpine vegetation system. Net primary productivity(NPP) is a key vegetation parameter and ecological indicator that can reflect both natural environmental changes and carbon budget levels. Given the unique geographical environment and strategic location of the TRHR, many scholars have estimated NPP of the TRHR by using different methods; however, these estimates vary greatly for a number of reasons. To date, there is no paper that has reviewed and assessed NPP estimation studies conducted in the TRHR. Therefore, in this paper, we(1) summarized the related methods and results of NPP estimation in the TRHR in a systematic review of previous research;(2) discussed the suitability of existing methods for estimating NPP in the TRHR and highlighted the most significant challenges; and(3) assessed the estimated NPP results. Finally, developmental directions of NPP estimation in the TRHR were prospected.