Abstract: Located in the hinterland of Qinghai-Tibet Plateau, the source region of the Yangtze River is featured with high altitude, low temperature, and harsh natural conditions. As a result, with the lack of hydrometeorological monitoring and basic data, study on the hydrological cycle in this region is inadequate. In this paper, the status of researches and observations of hydrologic cycle in the source region of Yangtze River is reviewed, and existing problems and challenges are expounded. First of all, the monitoring data could not meet research requirements due to insufficient monitoring stations and their unreasonable locations as well as difficulties in operating and maintaining equipment in such unfavorable circumstances. Research on the mechanism of hydrologic cycle needs to be deepened. Such mechanism involves the trend of water resources variation, runoff of underlying surface, groundwater transport, and etc. Moreover, the structure of hydrological simulation models should be enhanced, and the applicability and versatility await verification. Measures to tackle these problems are presented as follows: monitoring stations and platforms need to be upgraded by collaborative efforts from multi-departments and trans-disciplines; international corporation in scientific research can be intensified; information service and social benefits should be taken into consideration; prototype observation and fundamental theoretical research need to be improved. Innovations should also boost in terms of observation approach, atmospheric-solid-liquid water conversion, water balance, hydro-thermal coupling, hydrologic models for alpine area, as well as global climate change impact.

Key words: hydrology cycle, global climate change, meterological and hydrological monitoring stations, research countermeasures, source region of the Yangtze River