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Geological records of climate change since the last glaciation in South China, a core area of the East Asian monsoon, are key to understanding secular variation in the monsoon system. However, with the exception of the speleothems, records from this area with independent age control are few. We investigated aeolian sand deposition on a sand hill on the shore of Poyang Lake in South China and reconstructed the chronological sequence of aeolian deposition using Optically Stimulated Luminescence (OSL) dating. Without exception, all aeolian sediments were deposited within seven periods that generally match the timing of Heinrich events and other cold periods in Greenland. We argue that aeolian sand accumulation in this region is most likely forced by extreme aridity driven by weakening of the summer monsoon, while the characteristics of this deposition are influenced by winter monsoon intensity. The monsoon shifts revealed here suggest a possible link between North Atlantic cooling and summer monsoon strength in South China, and support the intensities of cooling phases recorded in Greenland ice cores. [ABSTRACT FROM AUTHOR]

The Hunshandake Sandy Land, which is highly sensitive to climate change, is located in North China along the margins of the area influenced by the East Asian monsoon. The upper reach of the Xilamulun River, which drains the Hunshandake Sandy Land, provides an opportunity to test the response of a river landform within a sandy region to climate change. We investigated terraces at 4 sites along a 38-km-long stretch and performed OSL dating on 26 terraces. The dating results revealed 23 terraces with unsaturated ages ranging from 0.3 ka to 36.2 ka. The observed relationship between the terrace heights and ages is abnormal, i.e., the terrace age does not increase with the terrace height. In this case, aeolian and fluvial interactions were analyzed, and a precipitation-dominated terrace formation model was developed. Higher terraces formed when the riverbed aggraded due to decreased sediment discharge and increased aeolian sand input during a period of reduced precipitation. In contrast, lower terraces developed when the riverbed eroded during a period of enhanced precipitation. We conclude that the terraces along this Hunshandake Sandy Land river respond to precipitation changes, even in the absence of background uplift. [ABSTRACT FROM AUTHOR]

• Vegetation greening has been found in one of the largest deserts in northern China. • This greening trend can be related to recent climatic change and human interference. • Ecological restoration projects have accelerated the rate of vegetation recovery. • Desert vegetation is influenced by precipitation variations regulated by El Niño. Vegetation is usually sparse in the desert regions, but it plays important roles in stabilizing sand dunes and combating desertification. Establishing how desert vegetation responds to changes in both natural forcing and anthropogenic interference is essential for better understanding desertification processes and their future dynamics. In this study, a comprehensive analysis of NDVI time series data in combination with climate reanalysis data and topographic data was conducted to investigate the possible effects of different external factors on desert vegetation in the Tengger desert, one of the largest deserts in northern China. The results show that vegetation is mostly distributed near the desert margins and in the interdune areas with relatively low and flat topography. Multiple NDVI datasets indicate a consistently greening trend over the entire desert during the last forty years, and the greening rates are higher at sites with sand fixation and vegetation restoration practices. After a few decades of restoration practices, vegetation greenness in these sites is approaching their natural states, but they still show large interannual variability associated with precipitation fluctuations. Therefore, the greening trend of the entire desert could be related to recent climate change towards wetter, warmer and less windy conditions, while human efforts have accelerated the rate of vegetation recovery in the restoration sites. Our study implies that the present climate change has produced conditions favorable for continued vegetation increase in the drylands of northern China, and this trend has been facilitated by policy-driven restoration projects. The combined effects of climate change, topography and human interference on desert vegetation should be considered in future restoration practices. [ABSTRACT FROM AUTHOR]

Reconstructing the Plio-Pleistocene sedimentary history of the Yellow Sea, is important for understanding the long-term influence of the Yellow River (Huanghe) and/or Yangtze River (Changjiang) on the Asian marginal seas and to further constrain any links between river development, regional paleoenvironmental change, tectonic deformation and/or global climate change. Here we present the first high-resolution clay mineral record combined with Sr-Nd isotopic compositions from a 300-m long sediment core recovered in the western South Yellow Sea. Our study suggests that large-scale transgression in the Yellow Sea occurred after ∼0.8 Ma, possibly related to tectonic subsidence of eastern China coast and the Min-Zhe Uplift. In contrast, the sedimentary environment of Bohai and Yellow Seas was mainly dominated by fluvial/lacustrine deposits at 3.5–0.8 Ma. Provenance analysis suggests a major change in sediment provenance from the Yangtze River to the Yellow River at ∼0.8 Ma, which corresponds to the timing of the final integration of the Yellow River in its present form. At the same time the major channels of the Yangtze River migrated from the South Yellow Sea to the modern Yangtze River delta due to the subsidence of east China coast. The consistence in timing of the provenance transition and large-scale regional marine transgression suggests that tectonic deformation, rather than climate change, is the first-order control on the evolution of the Yellow and Yangtze Rivers and sedimentary environmental change in the Bohai and Yellow Seas. • A major change in sediment provenance in South Yellow Sea from the Yangtze River to Yellow River occurred at 0.8 Ma. • Large-scale transgression in the Yellow Sea began at 0.8 Ma, possibly related to subsidence of the Min-Zhe Uplift. • Tectonic deformation, rather than climate change, is the major control on the evolution of the Yellow and Yangtze Rivers. [ABSTRACT FROM AUTHOR]