The cryosphere has a highly sensitive and important feedback effect on climate. As the most active component of the cryosphere, snow plays an important role in climate variability. Global climate change has profound impacts on temperate and boreal forest ecosystem, particularly due to its influence on snow. Mountain precipitation and melted snow/ice are important sources of water in ACA. One of the largest basins in the arid region of inland Asia, the Ili-Balkhash Basin (IBB) receives most of its water resources from orographic rain and ice/snow meltwater from the mountains. Because of its aridity and correspondingly fragile ecological environment, the IBB has special status in global climate change research. In this study, the response relationship of tree radial growth, stable carbon and oxygen isotopes with temperature, precipitation and main snow parameters in the whole Ili-Balkash Lake basin was analyzed. Then, the snowfall changes in Ili-Alatau since 1850 were reconstructed based on tree-ring stable oxygen isotopes. Main research conclusions: 1) The previous winter and current summer precipitation have important influence on the radial growth of P. schrenkiana., and the spatially inhomogeneous effects of snow on subsequent growing-season tree growth. The radial growth response of P. schrenkiana to snow shows a weak-strong-weak trend from west to east across the Ili-Balkhash Basin. This spatial difference is mainly related to precipitation; as snow has little effect on tree growth in regions that receive more precipitation. Thus; winter snow has an important influence on the radial growth of trees in regions that receive limited amounts of precipitation. Snow change did not significantly affect tree-ring stable carbon isotope fractionation, but snowfall was the main limiting factor for tree-ring oxygen isotope in the alpine Tianshan Mountains; 2) The alpine snowfall reconstruction reveals that the WP has increased significantly in southern Kazakhstan over the past 166 years, at a rate of 1.7 mm/decade. Prior to the 1910s, there was relatively less alpine snowfall; since the 1920s, there has been more. The WP reconstruction indicates that alpine snowfall increased during the1860–1880s, 1910–1920s, 1940–1950s, and from the 1980s to present, and decreased during the other decades. Since the 1980s, alpine snowfall of southern Kazakhstan continues and increases rapidly. The moisture of regional winter snowfall is likely to come from the Atlantic Ocean and be carried by westerly winds.
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