High Asian glaciers and precipitation have directly or indirectly influenced the freshwater supply of billions of people and natural ecosystems in surrounding areas. To better understand the hydroclimatic changes in the High Asian transboundary river basins in the context of global warming, more precipitation‐sensitive proxy data are needed. In this paper, we used the tree‐ring cores of Pinus densata and Picea brachytyla from the southern Tibetan Plateau (TP) to establish a tree‐ring‐width composite chronology and estimate hydrological annual (September–August) precipitation (r2 = 47.0%, p <  0.01) for the Lohit River basin from 1720 to 2019. Our reconstructed precipitation was closely linked with the glacier mass balance of Shishapangma peak, which may provide us with some evidence for glacier fluctuations in the southern TP. Our precipitation reconstruction successfully captured recent dry trends and generally agreed with other tree‐ring‐based precipitation reconstructions from nearby regions. In addition, reconstructed precipitation variations were inconsistent with recorded monsoon‐season Brahmaputra discharge.

Geographic national conditions monitoring is an important new mission of China. China geography census is a major national survey of national condition and power, and it is a basic work to access the fundamental natural, ecological and human activities information of land surface. Land cover classification data is an important part of the China geography census, and it is the base of the subsequent statistical analysis. So the accuracy of the classification result will directly affect the data quality. In order to solve this problem, an extensive collection of typical land cover examples and problems is carried out, and the 94 confusing land cover groups are given. Meanwhile, the confusing causes are analyzed comprehensively, the association analysis maps are provide. And 6 suggestions provided in order to improve the final classification accuracy. The results of this study can provide scientific reference for the land cover classification of China geography census.

We present a runoff reconstruction for the Bailong River based on the composite chronology developed from four sampling sites of Pinus tabulaeformis in the China north–south transition zone. The runoff reconstruction, spanning 1601–2013 CE, was developed by calibrating tree‐ring data with the instrumental runoff record. Runoff reconstruction accounted for 44.3% of the actual runoff variance during the common period 1958–2010 and provided a long‐term perspective on hydrological change in the China north–south transition zone. In the past 413 years, high‐ and low‐runoff years accounted for 15.50% and 15.98%, respectively. Of all the 17 extreme hydrological events, 14 of them are extremely high‐flow years, and 17th century was the wettest period during the past 413 years. The preliminary analysis results show that there is a relationship between our runoff reconstruction and the Atlantic multidecadal oscillation at multidecadal scale. Since the 1990s, runoff in the China north–south transition zone has also seen a significant decrease as a result of dry trends of the source region.