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| 1 | Climate as the dominant control on C_3 and C_4 plant abundance in the Loess Plateau: Organic carbon isotope evidence from the last glacial-interglacial loess-soil sequences显示文摘Abundance of C3 and C4 photosynthesis plants can be inferred relatively from stable carbon isotopic composi-tion of organic matter in soils. The samples from five sequences of the last glacial-interglacial loess-soil in the Chinese Loess Plateau have been measured for organic carbon isotopic ratios (d 13Corg). The organic carbon isotope data show that relative abundance (or biomass) of C4 plants was increased ca. 40% for each sampling site from the last glacial maximum (LGM) to Holocene optimum, and increased southeastward on the Loess Plateau during both periods of LGM and Holocene. Statistic analyses on the steady maximum d 13Corg values of Holocene soils and modern climatic data from the Loess Plateau and Inner Mongolia indicate that the C4 plant abundance increases with increasing temperature and decreasing precipitation. The C4 plant abundance is related much closer with mean April tem-perature and precipitation than annual. These results lead us to deduce following conclusions. First, temperature is the major factor for control on variations in C4 plant abundance in the Loess Plateau from the last glacial to interglacial. In the absence of favorable temperature condition, both of low moisture and low atmospheric CO2 concentration are insufficient to drive an expansion of the C4 plants in the plateau. Second, d 13Corg in the loess-paleosol sequences, as a proxy of the relative abundance of C4 plants in the Loess Plateau, could not be used as an indicator of changes in the summer monsoon intensity unless the tem-perature had changed without great amplitude. Since all C4 plants are grasses, finally, the increase of the C4 plants supports that forest has not been dominant in the ecosystem on the Loess Plateau during Holocene although precipitation and atmospheric CO2 were largely increased relative to those during LGM. | GU Zhaoyan, LIU Qiang, XU Bing, HAN Jiamao, YANG Shiling, DING Zhongli & LIU Tungsheng Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Gu Zhaoyan (e-mail: zgu@ 95777.com) | 2003 | Chinese Science Bulletin2003，48，12： | 14 |
| 2 | Methods and application of using detrital zircons to trace the provenance of loess显示文摘The composition of single-grain detrital zircons is an effective provenance indicator of loess,and sheds new light on dust formation and transportation.Here we review the features of detrital zircons and their use as a provenance indicator,including internal structure,trace element,U-Pb age spectrum and Hf isotopic compositions,and present a case study from the Horqin sandy land and its surrounding loess.The loess samples have detrital zircon age peaks in range of 2600-2300,2100-1600,and 600-100 Ma,of which the 2600-2300 Ma zircon grains mainly have positive Hf(t) values(3.4-8.7),the 2100-1600 Ma zircon grains mainly have negative Hf(t) values(10.1-6.8),and the 600-100 Ma zircon grains have a variable Hf(t) values ranging from 21 to 15.9.The detrital zircon signatures of the loess are similar to the Horqin sandy land,but clearly different from the Chinese Loess Plateau and central-western deserts,implying that the loess is transported mainly from the Horqin sandy land in the Last Glacial period.Comparing these with neighboring tectonic units,we found that zircon populations at 2600-2300,2100-1600,and 600-100 Ma with negative Hf(t) values may come from the northeast North China Craton(NCC),and those at 600-100 Ma with positive Hf(t) values may come from the east Central Asian Orogenic Belt(CAOB).It is estimated that the two sources contribute equally to the Horqin sandy land and the surrounding loess. | XIE Jing YANG ShiLing DING ZhongLi | 2012 | Science China Earth Sciences2012，55，11： | 10 |
| 3 | Seven million-year iron geochemistry record from a thick eolian red clay-loess sequence in Chinese Loess Plateau and the implications for paleomonsoon evolution显示文摘Recently, the Tertiary red clay sequence underlying Pleistocene loess has attracted much attention. The remarkable progress is the recognition that the Tertiary red clay sequence is also wind-blown in origin, thus providing a good opportunity to reconstruct long-term monsoon changes. In contrast to the loess deposits, the magnetic susceptibility and the pedogenic characteristics are almost independent of each other in the red clay, thus challenging the validity of the readily measurable magnetic susceptibility in describing the monsoon history recorded by the red clay. With the objective to address the long-term East Asia summer monsoon evolution, the free to total Fe2O3 ratios were calculated in a continuous eolian red clay-loess sequence at Lingtai, the Chinese Loess Plateau, which has a thickness of 305 m and a basal age of 7.0 Ma. The seven million-year Fe2O3 ratio record from the red clay-loess sequence indicates that (i) variations of the free to total Fe2O3 ratios of the loess can correlate | Shiling Yang Zhongli Ding | 2001 | Chinese Science Bulletin2001，46，4： | 9 |
| 4 | Pedogenic carbonate isotope record of vegetational evolution since late Miocene in Loess Plateau显示文摘lsotopic analyses for paleovegetational evolution have been carried out on samples of the pedogenic carbonate nodules in the Red Clay-Loess sequence at Lingtai (35°N), the Loess Plateau. Stable carbon isotopic composition indicates that ( ⅰ ) C4 plants might be present at least by7.0 Ma; ( ⅱ ) C4 plants expanded gradually between ~4.0 and ~3.2 Ma, and their biomass fraction was up to 50%; and ( ⅲ ) the biomass of C4 vegetation since ~2.0 Ma seems to have been decreased to the level (about 20%) before 4.0 Ma. C4 plant expansion at Lingtai cannot be fully understood with the 'global C4 expansion' model because it occurred much later up to 3.0 Ma than in Pakistan, which indicates that some changes in the regional climatic system may also contribute to C3/C4 shift except changes in atmospheric CO2 concentrations and temperature. The latitudinal zone for C3/C4 transition seems to move southwards slightly in East Asia, compared with the case in North America where 37°N is the ideal | Shiling Yang Zhongli Ding Zhaoyan Gu Jimin Sun Shangfa Xiong | 1999 | Chinese Science Bulletin1999，44，11： | 6 |
| 5 | Four Methods to Estimate Minimum Miscibility Pressure of CO2-Oil Based on Machine Learning显示文摘Summary of main observation and conclusion CO2 flooding accounts for a considerable proportion in gas flooding.Using CO2 as a gas displacement agent is benefit for enhanced oil recovery(EOR),and the alleviation of the greenhouse effect by the permanent storage of CO2 in the crust.Minimum miscibility pressure(MMP)of CO2-oil is a key factor affecting EOR,which determines the yield and economic benefit of crude oil recovery.Therefore,it is of great importance to use fast,accurate and cheap prediction methods for MMP estimation.In the present study,to evaluate the reliability of four recently developed prediction models based on machine learning(i.e.,neural network analysis(NNA),genetic function approximation(GFA),multiple linear regression(MLR),partial least squares(PLS)),136 sets of data are selected for calculation via outlier analysis from 147 sets of data.Afterwards,we compared the four models with existing prediction models from the literature.The analysis of correlation coefficients and multiple error functions shows that the four models can solve the MMP prediction problem well,and the model using intelligent algorithm has a higher prediction accuracy than the simple linear model.Besides,intelligent methods based on similarity algorithm have little difference from each other.Finally,a sensitivity analysis was conducted. | Ding Li Xiangliang Li Yinghua Zhang Lixin Sun Shiling Yuan | 2019 | Chinese Journal of Chemistry2019，37，12： | 4 |
| 6 | Synchronous drying and cooling in central Asia duringlate Oligocene显示文摘Aridification of central Asia during late Oligocene and Early Miocene has been documented by numerous eolian records from the North Pacific and central Asia. However, direct evidence of aridity from the interior of the arid zone is still rather scarce. To better reconstruct the climate history in central Asia during the late Oligocene, we have analyzed ostracod assemblages and gypsum content in the sediments from the lacustrine Jingou River section in the northern Tianshan Mountains. Our results show that the cold water species Candona cf. Neglecta and Pseudocandona albicans replaced the warm water species Ilyocypris bradyi and Ilyocypris sp. to become the dominant species at 23.8 Ma, indicating significant cooling in central Asia at that time. At the same time, a substantial increase in gypsum content indicates the intensification of central Asian drying. The synchronous cooling and drying approximately coincided with the Oi2b.1 and/or Mi1 events, implying a causal linkage between late Oligocene global cooling and central Asian aridity. | DONG XinXin DING ZhongLi YANG ShiLing LUO Pan WANG Xu JI JunLiang | 2013 | Chinese Science Bulletin2013，58，25： | 3 |
| 7 | Pleistocene chemical weathering history of Asian arid and semi-arid regions recorded in loess deposits of China and Tajikistan显示文摘 | Yang Shiling Ding Feng Ding Zhongli | 2006 | Geochimica et Cosmochimica Acta2006，70，7： | 1 |
| 8 | A comparative study of QoS routing schemes that tolerate imprecise state information显示文摘 | Xin Yuan Wei Zheng Shiling Ding | 2002 | Proceedings of 11th international conference on computer communications and networks2002，10，： | 1 |
| 9 | Coeval changes in grain size and sedimentation rate of eolian loess, the Chinese Loess Plateau显示文摘 | Ding Zhongli Yu Zhiwei Yang Shiling | 2000 | Geophysical Research Letters2000，28，： | 1 |
| 10 | Efficient and Practical Syntheses of Enantiomerically Pure (S)-(−)-Norcryptostyline Ⅰ, (S)-(−)-Norcryptostyline Ⅱ, (R)-(+)-Salsolidine and (S)-(−)-Norlaudanosine via a Resolution-Racemization Method显示文摘Four racemic tetrahydroisoquinolines(RS)-(±)-1-4 were prepared from homoveratrylamine via amidation,Bischler-Napieralski reaction and the subsequent reduction.The enantiomerically pure tetrahydroisoquinolines(S)-(−)-norcryptostyline Ⅰ[(S)-(−)-1],(S)-(−)-norcryptostyline Ⅱ[(S)-(−)-2],(R)-(+)-salsolidine[(R)-(+)-3]and(S)-(−)-norlaudanosine[(S)-(−)-4]were then obtained in 45%,40%,41%and 38%yields,respectively,via resolution of the racemic compounds(RS)-(±)-1-4 with half equivalent of chiral acids.In addition,the enantiomerically enriched compounds(R)-(+)-1,(R)-(+)-2,(S)-(−)-3 and(R)-(+)-4 from the mother liquors were efficiently racemized via a one-pot redox method in almost quantitative yields. | Ruiheng Zhu Zhangli Xu Wei Ding Shiling Liu Xiaoxin Shi Xia Lu | 2014 | Chinese Journal of Chemistry2014，32，10： | 1 |
| 11 | A graphical criterion of planarityfor RNA secondary structures with pseudoknots in Rivas-Eddy class显示文摘 | Gao Shile Ding Kequan | 2008 | Theoretical Computer Science2008，395，1： | 1 |
| 12 | Pleistocene chemical weathering history of Asian arid and semi-arid regions recorded in loess deposits of China and Tajikistan显示文摘 | Shiling Yang Feng Ding Zhongli Ding | 2005 | Geochimica et Cosmochimica Acta2005，，7： | 1 |
| 13 | Color reflectance of Chinese loess and its implications for climate gradient changes during the last two glacial-interglacial cycles 显示文摘 | Yang Shiling Ding Zhongli | 2003 | Geophysical Research Letters2003，30，： | 1 |
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