Abstract:Precipitation is a main factor that controlling the dynamic change of ecosystem structure and affecting the ecosystem biodiversity. In the arid and semi-arid areas of China, precipitation plays a particularly important role in the growth of vegetation. Vegetation is one of the most important indicators of ecological environment change, and it is also the most active and important components of the ecosystem in arid and semi-arid areas. Precipitation use efficiency (PUE) of vegetation is an index that represents the response characteristics of vegetation productivity to precipitation changes and the ability of vegetation to convert precipitation into biomass. More and more researches have been conducted on the PUE of vegetation precipitation. Nowadays, based on remote sensing data and model estimation, there are still few studies on the impact analysis of the PUE in arid and semi-arid areas of China which need to be further improved. Based on the data of average annual precipitation, air temperature, land use type, topographic, and net primary productivity of vegetation in arid and semi-arid areas of China from 2000 to 2020, this study analyzed spatial and temporal characteristics of vegetation precipitation use efficiency in arid and semi-arid areas. The results showed that:(1) The average PUE of all vegetation in arid and semi-arid areas of China from 2000 to 2020 was 0.41 g C m-2 mm-1, and the order of PUE of different vegetation was grassland < wetlands < bush < arable land < forest land. (2) The inter annual variation of vegetation PUE showed an overall fluctuating upward trend, with an increasing rate of 0.004 g C m-2 mm-1. For trend analysis, the area of significant improvement trend accounted for 12.24% of the total area. (3) Increasing temperature promoted the PUE of most vegetation to varying degrees while increasing precipitation inhibited the PUE increase of vegetation in most regions. In the area with less vegetation, the two climatic factors of temperature and precipitation almost did not affect the use efficiency of vegetation precipitation. (4) With the increasing of altitude, the PUE of vegetation showed a trend of first decrease, then increase, and then decrease. The maximum of the PUE of vegetation occured when the elevation gradient was 3001-4000 m, and the minimum vegetation PUE occured when the elevation gradient was 5001-6928 m. With the change of altitude, air temperature was still positively correlated with vegetation PUE, while precipitation was still negatively correlated with vegetation PUE. The results can provide scientific reference for the protection, restoration and sustainable utilization of ecosystems in arid and semi-arid areas in China.