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There are a large number of glaciers and lakes developed in the Nyang Qu Basin of China. Recent climate change has significant impacted on the high-mountain glacial environment. Rapid melting of glaciers contributes to the formation and expansion of moraine-dammed lakes which increase the probability of glacial lake outburst floods (GLOFs). We calculated a multi-temporal lake inventory based on (1) topographic maps in the 1970s, (2) satellite imageries from 1990 to 2016, (3) First Chinese Glacier Inventory (FCGI), (4) Glacier Inventory of Southeastern Tibet (GIST) and (5) meteorological data. A total of 880 lakes (>0.01 km2) have been mapped in 2016, with 318 being glacial lakes (GLs) and 462 non-glacier lakes (NGLs). Most of the lakes were mainly located at 4500 m a.s.l. and the lakes dominated by small lakes (<0.1 km2) where the change of their actual sizes are more significant compared to the larger ones. Meanwhile, we found [ABSTRACT FROM AUTHOR]

• Increased precipitation consistently promotes biomass production in both grasslands. • Elevated temperature suppresses biomass production in temperate grassland. • Elevated temperature promotes biomass production in alpine grassland. • Climatic factors play a pivotal role mainly by soil factors. Comparisons of vegetation production between temperate and alpine grasslands are not well studied, and the understanding of the underlying mechanisms is still incomplete. To address this issue, we selected the Inner Mongolia and Tibet regions to conduct large-transect surveys for temperate grassland (TG) and alpine grassland (AG), respectively, in China, to reveal the universal and differential mechanisms of above- and belowground biomass production (GB, AGB and BGB) and precipitation use efficiencies (PUE) in the two grasslands. The relative importance of climatic factors on biomass and PUE is greater than that of soil and biological factors. Elevated mean annual precipitation (MAP) consistently increased GB in both TG and AG. Increased mean annual temperature (MAT) reduced GB by weakening the soil nutrient status in TG, whereas it increased GB by improving the soil nutrient status in AG. MAP promoted more AGB than BGB in TG, whereas MAT affected BGB more than AGB in AG. When the multicomponent heterogeneity of other factors in grasslands was eliminated, the effect of MAP on GB remained significant for both TG and AG. After removing the effect of multifactorial heterogeneity, however, the significant effect of MAP on PUE of the two grasslands was largely enhanced. From these results, we can conclude that climatic factors do not always exert identical effects on different grasslands. In particular, highlighting the divergent mechanisms of biomass production and precipitation use efficiency between temperate and alpine grasslands can improve the understanding of the carbon sink and hydraulic sensitivity of various grasslands. [Display omitted] [ABSTRACT FROM AUTHOR]