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| 1 | Chinese deserts and sand fields in Last Glacial Maximum and Holocene Optimum显示文摘The Last Glacial Maximum (LGM, c. 26-16 ka) and the Holocene Optimum (HO, c. 9-5 ka) were characterized by cold-dry and warm-wet climates respectively in the recently geological Earth. How Chinese deserts and sand fields responded to these distinctive climatic changes is still not clear, however. To reconstruct environments of the deserts and sand fields during the LGM and HO is helpful to understand the forcing mechanisms of environment change in this arid region, and to test paleoclimatic modeling results. Through our long-term field and laboratory investigations, 400 optically stimulated luminescence (OSL) ages and more than 100 depositional records in the Chinese deserts and sand fields were obtained; on the basis of these data, we reconstruct spatial distributions of the deserts and sand fields during the LGM and HO. Our results show that the sand fields of Mu Us, Hunshandake, Horqin and Hulun Buir in northern and northeastern China had expanded 25%, 37%, 38% and 270%, respectively, during the LGM; the sand fields of Gonghe in the northeastern Qinghai-Tibetan Plateau had expanded 20%, and the deserts of Badain Jaran, Tengger in central northern China had expanded 39% and 29% separately during the LGM; the deserts of Taklimakan, Gurbantünggüt and Kumtag in northwestern China had expanded 10%-20% respectively, compared to their modern areas. On the other hand, all of the sand fields were nearly completely covered by vegetation during the HO; the deserts in northwestern and central northern China were reduced by around 5%-20% in area during this time. Lakes in this arid region were probably expanded during the HO but this conclusion needs more investigation. Compared with the geological distributions of deserts and sand fields, human activity has clearly changed (expanded) the area of active sand dunes at the present time. Our observations show that environmental conditions of Chinese deserts and sand fields are controlled by regional climate together with human activity. | LU HuaYu YI ShuangWen XU ZhiWei ZHOU YaLi ZENG Lin ZHU FangYing FENG Han DONG LiNa ZHUO HaiXin YU KaiFeng MASON Joseph WANG XiaoYong CHEN YingYong LU Qi WU Bo DONG ZhiBao QU JianJun WANG XunMing GUO ZhengTang | 2013 | Chinese Science Bulletin2013，58，23： | 40 |
| 2 | Carbon isotopic composition of modern soil and paleosol as a response to vegetation change on the Chinese Loess Plateau显示文摘The relationship between the carbon isotopic composition of paleosols and paleovegetation on the Loess Plateau is still unclear. One of the main reasons is that we are short of knowledge about the characteristics of the carbon isotopic composition of modern soil in this area. A preliminary investigation of the carbon isotopic compositions of the modern soil and the loess/paleosol sequence on the Loess Plateau shows that the carbon isotopic composition of modern soil is consistent with the distribution of modern plants on the Loess Plateau, where the ecosystem is dominated by a mixture of C4 and C3 plants. Comparing theδ13C values of modern soil and loess-paleosol sequences from the Xunyi profile, we conclude that C3 plants dominated the landscape during loess sediment stages, while C4 plants expanded during paleosol stages. | LIU Weiguo NING Youfeng AN Zhisheng WU Zhenghai LU Huayu CAO Yunning | 2005 | Science China Earth Sciences2005，48，1： | 24 |
| 3 | Evolution of the monsoon and dry climate in East Asia during late Cenozoic:A review显示文摘Climate in Eastern Asia is composed of monsoon climate in the east,arid and semi-arid climate in the north and west,and the cold and dry climate of Qinghai-Tibetan Plateau in the southwest.The underlying causes for the evolution of East Asian climate during late Cenozoic have long been investigated and debated,particularly with regards to the role played by the Qinghai-Tibetan Plateau uplift and the global cooling.In this paper,we reviewed major research developments in this area,and summarized the important results.Based on a synthesis of data,we propose that the Qinghai-Tibetan Plateau uplift alone cannot fully explain the formation of monsoon and arid climates in Eastern Asia during the past 22–25 Ma.Other factors such as the global ice volume and high-latitude temperature changes have also played a vital role.Moreover,atmospheric CO2changes may have modulated the monsoon and dry climate changes by affecting the location of the inter-tropical convergence zone(ITCZ),which controls the monsoon precipitation zone and the track of the East Asian winter monsoon during late Cenozoic.The integration of high-resolution geological record and numerical paleoclimate modeling could make new contributions to understanding the climate evolution and variation in eastern Asia in future studies.It could facilitate the investigation of the regional differences in East Asian environmental changes and the asynchronous nature between the uplift of Qinghai-Tibetan Plateau and their climatic effects.These would be the keys to understanding underlying driving forces for the evolution of the East Asian climate. | LU HuaYu GUO ZhengTang | 2014 | Science China Earth Sciences2014，57，1： | 23 |
| 4 | Pretreated methods on loess-palaeosol samples granulometry显示文摘Twenty representative samples were collected from the Chinese loess plateau and each sample was prepared in 6 different ways respectively in order to test the influences of pretreated methods on grain size measurement. The results show that (ⅰ) different pretreated methods can make a big difference for the samples granulometry; (ⅱ) soaking in distilled water for one day, and then treating with an ultrasonic machine for 10 min can make the sample dispersed. | Huayu Lu Zhisheng An | 1998 | Chinese Science Bulletin1998，43，3： | 20 |
| 5 | An erosional hiatus in Chinese loess sequences revealed by closely spaced optical dating显示文摘Chinese loess deposits are some of the best continental records of palaeoclimatic and pa- laeoenvironmental changes in the late Cenozoic. Many investigations have shown that the long-time climate variations recorded by the loess-paleosol sequences can be correlated with global environ- mental changes. However,there are still some foundational questions concerning loess deposition that are not well answered,casting uncertainty on many previous conclusions,especially high-resolu- tion palaeoclimatic records. In this study,three typical loess-paleosol sections spanning the last glacial cy- cle were closely sampled for optically stimulated lu- minescence (OSL) dating and palaeoclimate inter- pretation along a northwest-southeast transect in Chinese Loess Plateau. Results show that there is a 4-5 ka hiatus in the typical loess deposits,and as a consequence suggests that the loess record is not continuous over millennial time scales. As such,pre- vious conclusions on climatic and environmental changes at millennial-centennial time scale,recon- structed through the loess record,should be reinves- tigated. The erosional hiatus may be forced by a pe- riod with strengthened East Asian winter monsoon and the less vegetation cover in the investigated sites. | LU Huayu Thomas Stevens YI Shuangwen SUN Xuefeng | 2006 | Chinese Science Bulletin2006，51，18： | 17 |
| 6 | Variation of Zr/Rb ratios on the Loess Plateau of Central China during the last 130000 years and its implications for winter monsoon显示文摘To find a new index of winter monsoon without effects of chemical weathering and pedogenesis is an important task in loess research. Chemical analysis of five grain size fractions (i.e. >32μm, 32-20μm, 20-8μm, 8-2μm and <2μm) show that Zr is enriched in coarser grain size, while Rb is concentrated in finer fractions. An excellent correlation occurs between Zr/Rb ratios and mean grain size in loess units (L1LL1 and L1LL2) from Huanxian and Xifeng sections, reflecting that Zr/Rb ratios increase when grain size is coarser. Due to immobility of the two elements during the postdepositional process, Zr/Rb ratios can eliminate the effect of weathering and pedogenesis and serve as an excellent proxy on winter monsoon variation. The Zr/Rb ratio curves of the Huanxian, Xifeng and Luochuan sections during the last 130000 years show that the winter monsoon strength was very weak during MIS 3, which corresponded to the intensity during MIS 5. | LIU Lianwen CHEN Jun CHEN Yang JI Junfeng LU Huayu | 2002 | Chinese Science Bulletin2002，47，15： | 15 |
| 7 | Millennial-scale climate change since the last glaciation recorded by grain sizes of loess deposits on the northeastern Tibetan Plateau显示文摘Whether climatic changes in high latitudes of the Northern Hemisphere since the last glaciation have effects on the Tibetan Plateau monsoon, and the variation characteristics of the Plateau monsoon itself are still not solved but of great significance. The 22-m high-resolution Ioess-paleosol sequence in the Hezuo Basin on the northeastern Tibetan Plateau demonstrates that the Plateau winter monsoon experienced a millennial variation similar to high latitude Northern Hemisphere, with cold events clearly correlated with Heinrich events but less for the warm events (Dansgarrd-Oeschger events). It may indicate that the climate system at high latitudes in the Northern Hemisphere had played an important role in both the Plateau monsoon and the high-level westerlies. On 10^4 year scale, there are two distinct anomalous changes, which are not found in the records from high latitude northern hemisphere, revealed by the loess grain size in the Hezuo Basin. One is that there was a considerable grain size increase at -36 kaBP, suggesting an abrupt enhancement of the Plateau winter monsoon at that time; the other is that, during 43--36 kaBP, the grain size decreased distinctly, indicating a notable weakening of the Plateau winter monsoon around that period. Both of the two anomalies suggest that the Tibetan climate may have been controlled by some other factors, besides the high latitude climatic changes in the Northern Hemisphere. | Lü Lianqing FANG Xiaomin LU Huayu HAN Yongxiang YANG Shengli LI Jijun AN Zhisheng | 2004 | Chinese Science Bulletin2004，49，11： | 13 |
| 8 | Composition, origin and weathering process of surface sediment in Kumtagh Desert, Northwest China显示文摘Kumtagh 沙漠是在中国的八最大的沙漠之一,但是因为存取的困难,以前糟糕调查我们的学科交差的学习。在这份报纸, 33 件代表性的表面沉积样品从在实验室荒芜、分析的 Kumtagh 被收集获得重矿物质部件和 geochemical 元素内容。结果证明重矿物质的各种各样的类型在这些样品是在场的,与绿帘石和角闪石的高水平。Si 和艾尔收起化学作文的大部分。与上面的大陆人外壳(UCC ) 的 geochemical 元素的平均作文相比,除了 Si 和 Ca,所有元素被弄空到某个度;Fe, Mg, Ca, P, Ti 和 Mn 在他们的内容有高关联系数。矿物质和 Kumtagh 荒芜的沉积的 geochemical 作文在 Altyn Tagh 山脉和 Taklamakan 沙漠的附近与 Altyn Tagh 山脉,和冲积/洪水的扇子的表面沉积的岩石的有类似,显示 Kumtagh 荒芜的沉积的一主要来源位于 Altyn Tagh 山脉。在 Aqik 山谷和 Shule 河的更低的活动范围的冲积沉积物和湖沉积是容易的被侵蚀并且搬运由强壮在东北弯屈进 Kumtagh 沙漠,形成沙漠的另一来源扔。一张 A-CN-K 第三的图证明由 Na 和 K 的损失捱过的弱度化学药品发生在这些沉积,而 A-CNK-FM 第三的图建议 Fe 和 Mg 经历了重要化学区别。物理捱过过程为 mafic 矿物质在好粒子引起容易的侵蚀和丰富,这样粗糙的荒芜的沙粒子能相对在 Fe 和 Mg 被弄空。在经历不太化学的捱过的干旱区域的沉积的矿物质和 geochemical 作文被物理捱过主要影响。 | XU Zhiwei LU Huayu ZHAO Cunfa WANG Xianyan SU Zhizhu WANG Zhenting LIU Hongyi WANG Lixin LU Qi | 2011 | Journal of Geographical Sciences2011，21，6： | 13 |
| 9 | Changes in grain-size and sedimentation rate of the Neogene Red Clay deposits along the Chinese Loess Plateau and implications for the palaeowind system显示文摘The wind system responsible for transporting dust onto the Chinese Loess Plateau during the late Miocene and Pliocene is still unknown and recent investigations highlight many controversies. This report aims to investigate spatiotemporal changes in grain-size and sedi- mentation rate of the Neogene Red Clay deposits in north China and to explore palaeoclimatic changes during the late Miocene and Pliocene, in particular the palaeowind system that trans- ported dust. Samples were collected from eight Red Clay sections on the Loess Plateau. Meas- urement and analysis show that there is a clear southward decrease in the mean grain-size index and in the coarse particle fraction (>20 μm). At Jiaxian site on the northern Loess Plateau, the average mean grain-size is around 20 μm, while at Lantian site in the south, the mean is around 9 μm. The coarse particle fraction >20 μm makes up 24.4% and 5.6%, at the two sites respec- tively. This distinct diversity of grain-size in the aeolian Red Clay deposit between the north and south indicate that the palaeodust was transported mainly by northerly low-level winds. The grain-size variations in the Red Clay deposits can also be divided into three stages (the lower, the middle and the upper interval): grain-size of the lower stage is significantly coarser than that of the middle stage, but finer than that of the upper stage. As a consequence, the intensity of pa- laeowind and desiccation of the dust source region during the late Miocene and Pliocene can be divided into three stages: 6.2―5.4 Ma, 5.4―3.5 Ma and 3.5―2.6 Ma. Strength of the palaeowind during the middle stage (5.4―3.5 Ma) is weaker than that of the previous and subsequent stages and the intensity of palaeowind during the latest stage (3.5―2.6 Ma) is stronger than that of the early time (6.2―5.4 Ma). Variations in the sedimentation rate of the Red Clay deposit can also be divided into three stages: the earlier, the middle and the later interval. The sedimentation rate of the earlier stage is higher than during the middle stage, but lower than during the later one. This is a clear indicator of changes in the palaeowind intensity and aridity in the dust source region and may be linked with global ice volume changes during the late Miocene and the Pliocene. | WEN Lingjuan LU Huayu QIANG Xiaoke | 2005 | Science China Earth Sciences2005，48，9： | 12 |
| 10 | Earth surface processes and their effects on human behavior in monsoonal China during the Pleistocene-Holocene epochs显示文摘There is a wide diversity of landforms in China.The topography of three major terraces,decreasing in height stepwise from west to east,was formed by the early Miocene.With the commencement of the Great Northern Hemisphere Glaciations(GHGs)and the glacial-interglacial cycles in the Pleistocene,thick loess deposits accumulated in north China,and fluvial terraces were formed and lakes expanded and contracted in eastern and central China.The earliest evidence of hominins in China is dated to ~1.7 Ma;they occupied the monsoon-dominated region for a long interval,until the late Pleistocene,~50 ka.In this study,we investigated a large area rich in the relics and artifacts of early man.The results indicate that the early humans occupied riverine areas,especially medium-sized fluvial basins,and lake shores.Even in the relatively recent geological past,the occupation and abandonment of settlements were directly forced by the shifting of sand dune fields in the desert-loess transitional zone,which in turn was closely associated with variations in the monsoon climate and vegetation patterns.Our observations indicate that landforms were one of the main determinants of early human behavior,in that loess tableland,large alluvial plains,desert-Gobi areas,and the Tibetan Plateau,were not suitable environments for early human settlement.We infer that the early humans in China adapted their behavior to specific landforms and landform processes.The monsoon climate,which shapes the large-scale step-like pattern of fluvial landforms,promotes vegetation coverage and dominates soil formation,provides a crucial context for early human adaptation.The adaptation of early humans to earth surface processes in East Asia is investigated for the first time in this study.Future investigations will provide further information that will increase our understanding of the linkage between early human behavior and landform processes in East Asia. | LU Huayu ZHUO Haixin ZHANG Wenchao WANG Shejiang ZHANG Hongyan SUN Xuefeng JIA Xin XU Zhiwei WANG Xianyan | 2017 | Journal of Geographical Sciences2017，27，11： | 12 |
| 11 | Onset of Xiashu loess deposition in southern China by 0.9 Ma and its implications for regional aridification显示文摘The Xiashu loess is a typical Quaternary eolian deposit in southern China and represents an important terrestrial paleoclimate archive in this low-latitude monsoon region. However, the chronological framework of Xiashu loess deposition has yet to be established. Determining the timing of the onset of Xiashu loess deposition will allow researchers to better understand late Quaternary aridification across the Asian continent, the evolution of the East Asian monsoon and regional environmental changes in subtropical regions. Therefore, in this study, a systematic chronological study of the Xiashu loess is conducted to answer this question. For the first time, magnetostratigraphic classification reveals that the Matuyama/Brunhes(M/B) reversal is present in the Xiashu loess at two sites in Jiangsu Province, the Qingshan profile at Yizheng and the Dagang core in Zhenjiang.Based on the results of magnetostratigraphy and optically stimulated luminescence(OSL) dating, the age of the lower boundary of the Xiashu loess is estimated to be approximately 0.9 Ma. Consequently, this Xiashu loess deposit is the oldest reported to date and is comparable in age to the red soil deposit in Xuancheng, Anhui Province. The onset of Xiashu loess deposition by 0.9 Ma represents the further expansion of arid range in Asia in the late Quaternary in response to significant aridification and winter monsoon strengthening in this subtropical region. We suggest that these climate changes were primarily driven by global cooling and an increase in high-latitude ice volume in the Northern Hemisphere and that the initiation of Xiashu loess accumulation was a regional response of southern China to the 0.9 Ma global cooling event. | Xusheng LI Zhiyong HAN Huayu LU Yingyong CHEN Yang LI Xiaokang YUAN Yuwen ZHOU Mengyao JIANG Cunjuan LV | 2018 | Science China Earth Sciences2018，61，3： | 11 |
| 12 | Typical Geochemical Elements in Loess Deposit in the Northeastern Tibetan Plateau and Its Paleoclimatic Implication显示文摘Widespread and thick loess deposit in the northeastern Tibetan Plateau records paleoclimatic changes over the Quaternary period. In this study, we investigate a loess section located in a high terrace of the Huangshui River in the Xining Basin, and collect samples at 20-cm intervals by digging a well of 16-m depth (including paleosol S1 and S0 and several loess interlayers over the last glacial-interglacial cycle and the Holocene). Concentration of some active elements (Sr and Ca) and inert elements (Rb, Zr, Ti) in these loess samples are measured. The results show that ratios of those elements (oxide), such as Rb/Sr, Ti/Sr, and Zr/CaO ratios, would indicate sensitively paleoclimatic changes, especially the history of precipitation over the last glacial-interglacial and the Holocene. Moreover, the curves of Rb/Sr, Ti/Sr, and Zr/CaO ratios had almost the same variable trends from the bottom to the top and also closely correlated with values of magnetic susceptibility and the global marine δ18O record. But compared with the curves of magnetic susceptibility, the changes of ratios of these elements (oxide) are clearer and easy to understand. Therefore, the ratios of these typical chemical elements in the loess deposit may be used as an excellent index to investigate the history of paleoclimate, particularly precipitation changes in the northeastern Tibetan Plateau. | TAN Hongbing MA Haizhou ZHANG Xiying LU Huayu WANG Jianguo | 2006 | Acta Geologica Sinica(English Edition)2006，80，1： | 10 |
| 13 | Tree-Ring Latewood Width Based July–August SPEI Reconstruction in South China since 1888 and Its Possible Connection with ENSO显示文摘Our understanding of the long-term hydroclimate variations in South China is prohibited by the shortness of meteorological records. Paleoclimatic proxies, such as tree-rings, can be pursued to extend the meteorological records back for centuries to help us better understand hydroclimatic conditions. In this study, we reconstructed the July–August standardized precipitation–evapotranspiration index(SPEI_(Jul–Aug)) based on a newly developed 127-yr adjusted latewood width chronology from Tsuga longibracteata, South China. The chronology explained 40% of the actual SPEI_(Jul–Aug) variance in the period 1953–2014. The reconstructed SPEI_(Jul–Aug) can represent large-scale July–August SPEI variations over South China, including northern Guangxi, Hunan, and Guizhou provinces. From the perspective of the past 127 years, the extreme summer drought in 2013 was not unusual because more extreme drought events occurred in the first half of the 20th century. A significant 2.0–3.6-yr hydroclimatic cycle existed in the reconstruction, which indicated that the SPEI_(Jul–Aug) might be driven by El Ni?o–Southern Oscillation(ENSO). We further checked the time-dependency of the relationship between SPEI_(Jul–Aug) and ENSO and found that it was unstable. Their relationship was weak before the 1950s, became significant from the 1950s to early 1990s, and then dropped to be weak again and even out of phase since the early 1990s, which may be attributable to the significant westward extension of the western Pacific subtropical high. | Yesi ZHAO Jiangfeng SHI Shiyuan SHI Jian YU Huayu LU | 2017 | Journal of Meteorological Research2017，31，1： | 9 |
| 14 | Grain size distribution of quartz isolated from Chinese loess/ paleosol显示文摘Grain size distribution of bulk loess-paleosol and quartz chemically extracted from the loess/paleosol shows that mean size of the bulk samples is always finer than that of the quartz. The original aeolian depositions have been modified to various degrees by post-depositional weathering and pedogenic processes. The grain size distribution of the isolated quartz should be close to that of the primary aeolian sediment because the chemical pretreatment excludes secondary produced minerals. Therefore, the grain size of the quartz may be considered to more clearly reflect the variations of winter monsoon intensity. | SUN Youbin LU Huayu AN Zhisheng | 2000 | Chinese Science Bulletin2000，45，24： | 9 |
| 15 | Taphonomic and paleoenvironmental issues of the Pleistocene loessic Paleolithic sites in the Qinling Mountains, central China显示文摘Hinterland intermountain basins and northern and southern piedmonts of the Qinling Mountains accumulated a large amount of loess during the Pleistocene. The loess strata not only record local paleogeographic and paleoenvironmental changes, but also contain rich hominin fossils and Paleolithic remains. In the northern piedmont of the Qinling Mountains and the lower valley of the South Luohe River, the loess strata have multi loess-paleosol sequences with aeolian loess continuously accumulating during glacial and interglacial cycles. In contrast to the northern piedmont, loess stratigraphy in the hinterland intermountain basins of the Qinling Mountains is relatively thin and contains finer loess particles. In this 'mini' type of loess stratum, the density of Paleolithic remain generally is higher than the Loess Plateau in the north of the Qinling Mountains. Based on stratigraphic, chronological, and lithic artifacts analysis in recent years, it appears that the regional lithic assemblage belongs to the Oldowan(Mode I) lithic industry, and it is dominated by choppers, cores, flakes, and simple retouched flake tools from 1.15 to 0.6 Ma. Paleolithic open-air sites such as Gongwangling and Chenjiawo in the Lantian area, Shangbaichuan and Liuwan in the Luonan Basin, Qiaojiayao in the Lushi Basin, Longgangsi and Yaochangwan in the Hanzhong Basin, Guanmiao in the Ankang Basin, and the Yunxian Man Site in the Yunxian Basin are representative sites in the region; from 400 to 250 ka, the Longyadong cave site in the Luonan Basin inherited the characteristics of the local Mode I lithic industry, the stone assemblage is made up of cores, flakes, and small retouched flake tools, such as scrapers, points, and burins; during the period from 250 to 50 ka, bi-facially retouched Acheulean tools(Model II), such as hand-axes, picks, and cleavers, were commonly found in the Qinling Mountains region. The emergence of a large number of Model II artifacts indicates that local lithic industries went through a major transition process. Zhanghuokou, Guoyuan, and Huaishuping sites in the Luonan Basin, Diaozhai, Ganyu, Laochihe, and Xiehu sites in the Lantian area, Hejialiang site in the Hanzhong Basin are representative sites in this period; to the turn of the Late Pleistocene and Early Holocene, it may also exist a small flake-retouched tools lithic industry in the piedmonts of the northern and southern sides of the Qinling Mountains. The lithic assemblages in different stages of the Qinling Mountains region reflect the hominin behavioral changes and the development of lithic technology during the Pleistocene. | WANG SheJiang LU HuaYu | 2016 | Science China Earth Sciences2016，59，8： | 8 |
| 16 | Rb and Sr Geochemical Characterization of the Chinese Loess Stratigraphy and Its Implications for Palaeomonsoon Climate显示文摘Concentrations and distributions of Rb and Sr in loess and palaeosol samples from the Luochuan profile have been studied, in grain-size fractions and chemical forms. Results show that Rb is quite rich in the fraction of less than 2μm, and exits only in the residual phase, while Sr is distributed in sand and silt fractions, occurring in the residual and carbonate phases. Therefore, variations of the concentrations of Rb and Sr in loess and palaeosols are closely related not only to dustfall compositions depending on winter monsoon wind strength but also to summer monsoon-induced pedogenic intensity. This indicates that variations of Rb/Sr ratio in Chinese loess sequences represent cyclic alternations of East Asian summer and winter monsoon climates on the orbital time-scale. Variations in Sr concentrations along the sequence bear a high similarity to the oxygen isotope record of the deep sea sediments over the past 2.5 Ma, whereas variations in Rb concentrations are in good agreement with the record | CHEN Jun WANG Yongjin CHEN Yang LIU Lianwen JI Junfeng LU Huayu | 2000 | Acta Geologica Sinica(English Edition)2000，74，2： | 8 |
| 17 | Crescentic dune migration and stabilization: Implications for interpreting paleo-dune deposits as paleoenvironmental records显示文摘Paleo-dune deposits have been widely used as a proxy indicator of past dune activity, which is further used to reconstruct paleoclimates. However, recent studies have critically examined the reproducibility of dune chronologies and the complexity of paleo-dune deposits as paleoenvironmental records. This paper addresses questions on the paleoenvironmental implications of dune chronostratigraphies that have been raised by those reviews, in the specific case of crescentic dunes, using a case study from the Mu Us dune field, north-central China. The processes of turn-over and stabilization of relatively small crescentic dunes are first investigated by observational evidence. In combination with the analysis of a simplified sand preservation model and stratigraphic records, the effect of dune morphodynamics on sand preservation is demonstrated. It is especially evident that thick, nearly instantaneously deposited sand units record dune stabilization near the very end of a dune activity episode, while thin sand units may signal the preservation of sand deposited earlier in episodes of activity. Interpreting the distribution of luminescence ages that indicate sand deposition over time is not as simple as assumed in some previous work. Low frequency of sand ages could indicate an interval of either dune field stabilization or extensive dune activity but poor sand preservation. A peak of sand age frequency likely represents a shift in dune field activity towards stabilization, not a peak of active dune extent, especially if it partially overlaps with an independently identified interval of stabilization(e.g. one recorded by paleosols). The nature and magnitude of these biases in the distribution of sand ages over time are strongly affected by the magnitude of net sand accumulation, which is in turn related to sand supply, transport capacity and sand availability, and ultimately climate change. Relatively short dune stabilization and turn-over time(10~1 to 10~2 yrs) indicate that dune geomorphic processes can quickly respond to short-term disturbance, but the chronology of that response must be interpreted in light of how those processes influence age distributions. | XU Zhiwei Joseph A. MASON LU Huayu YI Shuangwen ZHOU Yali WU Jiang HAN Zhiyong | 2017 | Journal of Geographical Sciences2017，27，11： | 7 |
| 18 | Newly discovered Palaeolithic artefacts from loess deposits and their ages in Lantian,central China显示文摘Eight new Palaeolithic open-air sites were identified and 770 stone artefacts were collected from 2009 to 2011 in the Lantian area of the Bahe River valley, central China. Because the famous Homo erectus fossils were unearthed at the Gongwangling and Chenjiawo localities, and more than 30 Palaeolithic open-air sites were investigated in the 1960s in this region, the catchment of Bahe River is regarded as one of the most important hominin sites from the late early Pleistocene to the middle Pleistocene. These eight newly discovered open-air sites are located at the second(n = 6), third(n = 1) or higher terraces(n = 1) of the Bahe River. The Diaozhai section on the second terrace was sampled in detail. Two samples were collected for optically stimulated luminescence dating(OSL). The OSL results suggest that a buried lithic artefact layer at the Diaozhai site spans approximately 70–30 ka. The lithic assemblage analysis suggests that the stone artefacts were made of local pebbles/cobbles such as greywacke, quartz, sandstone and igneous rocks. The main percussion techniques that were used were direct hard hammer percussion and bi-polar techniques. The lithic artefacts comprise hammer stones, cores, flakes, retouched tools and flaking debris. Acheulian-type large cutting tools(LCTs) such as hand-axes, picks and cleavers were indentified in the Lantian region as well. This is the first time Acheulian-type LCTs from the late Pleistocene have been identified in this region. This study distinguishes age gaps between Western world and East Asian Acheulian-type tools. | Shejiang Wang Huayu Lu Hongyan Zhang Xuefeng Sun Shuangwen Yi Yingyong Chen Gaike Zhang Luda Xing Weigang Sun | 2014 | Chinese Science Bulletin2014，59，7： | 7 |
| 19 | Climatic and tectonic controls on the fluvial morphology of the Northeastern Tibetan Plateau (China)显示文摘The geomorphological evolution of the Northeastern Tibetan Plateau(NETP)could provide valuable information for reconstructing the tectonic movements of the region.And the considerable uplift and climatic changes at here,provide an opportunity for studying the impact of tectonic and monsoon climate on fluvial morphological development and sedimentary architecture of fluvial deposits.The development of peneplain-like surface and related landscape transition from basin filling to incision indicate an intense uplift event with morphological significance at around 10–17 Ma in the NETP.After that,incision into the peneplain was not continuous but a staircase of terraces,developed as a result of climatic influences.In spite of the generally persisting uplift of the whole region,the neighbouring tectonic blocks had different uplift rates,leading to a complicated fluvial response with accumulation terraces alternating with erosion terraces at a small spatial and temporal scale.The change in fluvial activity as a response to climatic impact is reflected in the general sedimentary sequence on the terraces from high-energy(braided)channel deposits(at full glacial)to lower-energy deposits of small channels(towards the end of the glacial),mostly separated by a rather sharp boundary from overlying flood-loams(at the glacial-interglacial transition)and overall soil formation(interglacial).Pronounced incision took place at the subsequent warm-cold transitions.In addition,it is hypothesized that in some strongly uplifted blocks energy thresholds could be crossed to allow terrace formation as a response to small climatic fluctuations(10~3–10~4 year timescale).Although studies of morpho-tectonic and geomorphological evolution of the NETP,improve understanding on the impacts of tectonic motions and monsoonal climate on fluvial processes,a number of aspects,such as the distribution and correlation of peneplain and the related morphological features,the extent and intensity of tectonic movements influencing the crossing of climatic thresholds,leading to terrace development,need to be studied further. | WANG Xianyan Jef VANDENBERGHE LU Huayu Ronald VAN BALEN | 2017 | Journal of Geographical Sciences2017，27，11： | 6 |
| 20 | Relationship between surface pollen assemblages and vegetation in Luonan Basin, Eastern Qinling Mountains, Central China显示文摘在华中的南方 Luohe 河的集水是为因为它位于在南方和北方中国之间的过渡地区,调查现代花粉环境关系的一个重要区域,对气候敏感的环境变化。在这研究,在十种植被类型下面的 40 件表面样品是镇定的揭示在花粉集合和植被之间的关系。结果证明表面花粉集合反映植被相当好。在森林表层土,树木的花粉内容的一般水准比 40% 大,并且 Selaginella sinensis 孢子高。至于稀少的森林草地和灌木社区,平均树木的花粉分别地是 13.2% 和 16.6% ,并且灌木花粉比草地样品的相对高。草地和农田被树和灌木花粉的低百分比描绘(<10% 并且 <1%) ,并且植物的高百分比(>80%) 。因为他们的疏开能力, Pinus, Quercus 和某另外的树木的花粉能显示地区性的植被。Quercus 花粉是在代表下面那么是 Pinus。Artemisia 花粉是显著地过去代表的,与植物范围有差的关联,并且可以思考人的骚乱。Gramineae 能显示植物相当好,但是与低表示一起。Chenopodiaceae 的高内容可能建议人的影响。占优势的 Selaginella sinensis 能被用作森林环境的指示物。簇分析和花粉集合的主要部件分析能区分森林和非森林植被很好。以前的方法擅长分开松并且混合森林,当后者是更稳定的并且能更好区分农田和另外的非森林区域时。PCA 的第一轴主要反映湿度。 | ZHANG Wenchao LI Chunhai LU Huayu TIAN Xianhua ZHANG Hongyan LEI Fang TANG Lingyu | 2014 | Journal of Geographical Sciences2014，24，3： | 6 |
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