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| 1 | A 16000-year pollen record of Qinghai Lake and its paleoclimate and paleoenvironment显示文摘The paleoclimate and paleoenvironment of Qinghai Lake indicated by a 16000-year pollen record are as follows. It was very cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400-13000, 11600-12000, and 11000-10400 aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, whereas the two warm periods between them, 12000-13000 and 11600-11000 aBP, respectively correspond to Boiling and Allerod periods. The temperature increased abruptly after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene, the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evolution and events of | LIU Xingqi SHEN Ji WANG Sumin YANG Xiangdong TONG Guobang ZHANG Enlou | 2002 | Chinese Science Bulletin2002，47，22： | 33 |
| 2 | Holocene vegetational and climatic variation in westerly-dominated areas of Central Asia inferred from the Sayram Lake in northern Xinjiang,China显示文摘Changes in the vegetation and climate of the westerly-dominated areas in Central Asia during the Holocene were interpreted using pollen-assemblages and charcoal data from a 300-cm-long sediment core of the Sayram Lake,northern Xinjiang.Accele-rator Mass Spectrometry(AMS) radiocarbon dating methods were applied to bulk organic matter of the samples.Artemisia spp./Chenopodiaceae ratios and results from principal component analysis were used to infer that the lake basin was dominated by desert vegetation before ca.9.6 cal.ka BP,which suggests a warm and dry climate in the early Holocene.Desert steppe/steppe expanded during 9.6-5.5 cal.ka BP,indicating a remarkable increase both in the precipitation and temperature during the mid-Holocene.Desert vegetation dominated between 6.5 and 5.5 cal.ka BP,marking an extreme warmer and drier interval.The steppe/meadow steppe recovered,and temperatures decreased from 5.5 cal.ka BP in the late Holocene,as indicated by the increased abundance of Artemisia and the development of meadows.Holocene temperatures and moisture variations in the Sayram Lake areas were similar to those of adjacent areas.This consistency implies that solar radiation was the main driving factor for regional temperature changes,and that the effect of temperature variations was significant on regional changes in humidity.The evolution of climate and environment in the Sayram Lake areas,which were characterized as dry in the early Holocene and relatively humid in the middle-late Holocene,are clearly different from those in monsoonal areas.Dry conditions in the early Holocene in the Sayram Lake areas were closely related to decreased water vapor advection.These conditions were a result of reduced westerly wind speeds and less evaporation upstream,which in turn were caused by seasonal changes in solar radiation superimposed by strong evaporation following warming and drying local climate. | JIANG QingFeng JI JunFeng SHEN Ji Ryo MATSUMOTO TONG GuoBang QIAN Peng REN XueMei YAN DeZhi | 2013 | Science China Earth Sciences2013，56，3： | 32 |
| 3 | Relationships between vegetation and stomata,and between vegetation and pollen surface soil in Yunnan,Southwest China显示文摘Surface pollen and stomata of 61 samples collected in a study area ranging from tropical seasonal rainforest to oak forest(Quercus spinosa) in the Yulong Snow Mountain region in Yunnan,China,are used to distinguish vegetation communities.The results show that tropical seasonal rainforest(and mountain rainforest),south subtropical evergreen broad-leaved forest,and Quercus shrub are distinguished effectively from other vegetation types by analysis of surface pollen.The south subtropical evergreen broad-leaved forest,Pinus kesiya forest and evergreen broadleaf forest are distinguished effectively from other types of vegetation by pollen analysis.However,P.yunnanensis forest is not distinguished from other vegetation types,and P.armandii,P.densata forest and temperate deciduous conifer mixed forest are not distinguished.The over-representation of Pinus pollen is the main reason that these vegetation communities are not distinguished from each other.Conifer stomata analysis is an effective tool for identifying and distinguishing different types of coniferous forest,and this method performs well even with a small number of sampling points. | SHEN HuaDong LI ChunHai WAN HeWen TONG GuoBang LIU JinSong DAN Johnson | 2013 | Chinese Science Bulletin2013，58，15： | 12 |
| 4 | Palynological evidence for vegetational and climatic changes from the HQ deep drilling core in Yunnan Province, China显示文摘The high-resolution pollen study of a 737.72-m-long lake sediment core in the Heqing Basin of Yunnan Province shows that the vegetation and climate of mountains around the Heqing Basin went through six obvious changes since 2.780 Ma B.P. Namely, Pinus forest occupied most mountains around the studied area and the structure of vertical vegetational belt was simple between 2.780 and 2.729 Ma B.P., reflecting a relatively warm and dry climate. During 2.729―2.608 Ma B.P., the areas of cold-temperate conifer forest (CTCF) and Tsuga forest increased and the structure of vertical vegetational belt became clear. According to percentages of tropical and subtropical elements growing in low-altitude regions rifely increased, we speculate that the increase of CTCF and Tsuga forest areas mainly resulted from strong uplift of mountains which provided upward expanding space and growing condition for these plants. Thus, the climate of the low-altitude regions around the basin was relatively warm and humid. Between 2.608 and 1.553 Ma B.P., Pinus forest occupied most mountains around the studied area and forest line of CTCF rose, which reflects a moderately warm-dry climate on the whole. During 1.553―0.876 Ma B.P., the structure of vertical vegetational belt in mountains around the studied area became complicated and the amplitude of vegetational belts shifting up and down enlarged, which implies that the amplitude of climatic change increased, the climatic associational feature was more complex and the climate was moderately cold at a majority of the stage. During 0.876―0.252 Ma B.P., there were all vertical vegetational belts existing at present in mountains around the studied area. The elements of each belt were more abundant and complex than earlier. At different periods in the stage vertical vegetational belts occurred as expanding or shrinking, and alternated each other. The amplitude of vegetational belts shifting up and down was the maximum in the whole section. This change suggests that the amplitude of climatic change was evidently larger than earlier, but the frequency reduced and the climatic associational feature was more complex. From 0.252 Ma B.P. to the present, the most time was characteristic of the expanding of Pinus forest and semi-humid evergreen broad-leaved forest (SEBF) in mountains around the studied area, while expanding time of other vegetational belts was very short, which reflects a smaller amplitude of cold and warm fluctuation. On the basis of the six obvious cycles of vegetational and climatic changes, there were still many times of secondary vegetational successions and climatic oscillations. Based on the above analysis, the forcing mechanism of vegeta-tional succession and climatic change in the Heqing Basin is further discussed. It is primarily consid-ered that main influential factors were exterior factors such as orbital parameters, etc., but the uplift of the Qinghai-Tibet Plateau played a very important function for environmental changes in the Heqing Basin at two times obvious increase of vertical vegetational belts and three climatic transitions. | XIAO XiaYun SHEN Ji WANG SuMin XIAO HaiFeng TONG GuoBang | 2007 | Science China Earth Sciences2007，50，8： | 10 |
| 5 | The plant diversity and its relationship with paleoenvironment since 2.78 Ma revealed by pollen records in the Heqing deep drilling core显示文摘Multifold palynological diversity indices calculated by pollen data of the Heqing deep drilling core are synthetically analyzed, the results show that the plant diversity rapidly increased and its fluctuant amplitude and frequency evidently largened during the stages of 2.729―2.608 Ma, 1.176―0.342 Ma and since 0.118 Ma respectively, while during the other periods the plant diversity was relatively low with a gentle fluctuation. To discuss further the relation between ancient plant diversity and paleoenvironment, it is considered that the plant diversity in the Heqing region lies on increase or decrease of vertical vegetational belts in mountains around the studied area and richness of components of these vegetational belts, and is controlled by amplitude of tectonic uplift of mountains and climatic changes. The high plant diversity during 2.729―2.608 Ma responded to the strong uplift of mountains at the stage, while the plant diversity greatly increased and its fluctuant amplitude and frequency markedly largened at about 1.176 Ma was obviously response to the Middle Pleistocene Transition. The plant diversity and its fluctuant amplitude and frequency increased further at about 0.991 Ma may be superposably affected by both the Middle Pleistocene Transition and the tectonic uplift. The plant diversity increased since 0.118 Ma may indicate that the southwest monsoon strengthened and humid climate more fitted many kinds of plants to grow. | XIAO XiaYun SHEN Ji WANG SuMin XIAO HaiFeng TONG GuoBang | 2008 | Chinese Science Bulletin2008，53，23： | 8 |
| 6 | Modern pollen-vegetation relationship based on discriminant analysis across an altitudinal transect on Gongga Mountain,eastern Tibetan Plateau显示文摘Quantitative relationship between modern pollen assemblage and altitudinal vegetation belt is crucial for the reconstruction of paleovegetation in the mountain regions.Modern pollen analysis on 70 topsoil samples was conducted across an altitudinal transect(1100-4500 m) on the eastern slope of Gongga Mountain in the eastern Tibetan Plateau with an elevation interval of 50 m.Distributions of major pollen types along the transect indicated a weak correlation between Pinus pollen and the elevation.Distributions of Picea and Abies pollen(percentage sum of 2%-8%) could fairly indicate the elevation range of 2700-3700 m,as well as the subalpine dark coniferous forest and the timberline in the region.High percentage intervals of alpine types of Ericaceae,Cupressaceae and Cyperaceae were correlated to the high-elevation regions(3700-4500 m) dominated by alpine shrub meadow and alpine meadow.Seven altitudinal vegetation belts on the eastern slope of Gongga Mountain were well defined by discriminant analysis conducted on the modern pollen assemblages,as reflected by high values of probability of modern analog.Most of the modern pollen assemblages(88.5%) were typical for the vegetation types at their sampling locations.Thus,the relationship between the modern pollen assemblages and vegetation across the altitudinal transect based on discriminant analysis can be applied to the quantitative reconstruction of paleovegetation changes in the mountain regions of the eastern Tibetan Plateau. | LI Quan GE QuanSheng TONG GuoBang | 2012 | Chinese Science Bulletin2012，57，35： | 6 |
| 7 | Primary Study on Quantitative Reconstruction of Middle-Late Eocene Climate in Jianghan Basin显示文摘This paper reports our primary effort in the quantitative reconstruction of paleoclimate based on the thrine in phytoecology of the affinity parent plants in the stratigraphic pollen records. The Eocene pollen data come from our former study on the Mingjia borehole 1 in the Jianghan basin. The fluctuating trend in the parameter curve of climate shows that the climate in the Middle Eocene in the Jianghan basin was more or less comparable with that of the present 22°-26°N, characteristic of a humid, semi humid central southern subtropical climate. The annual temperature at that time dropped by 1 ℃-4 ℃ in the Late Eocene, approximately equal to that of the present 23°-28°N of northern central subtropical climate. However, the climate composite at that time, characterized by higher temperature, small annual range and big fluctuation in precipitation, was quite different from the present one. The average temperature in January in the Middle Eocene, higher than that of today, ranged between 5 ℃ and 9 ℃, indicating that no effect of winter monsoon occurred in the Middle Eocene, though such an effect may have occurred occasionally in the Late Eocene. Major temperature decline is recognized at the depth of 2 100 m in the borehole, as was indicated by the decline in average January temperature, the increase in annual range, and the increase in the deciduous broad leaved types of trees in the spore pollen assemblage. The sharp fluctuation in the annual precipitation, usually raging from 300 to 1 700 mm, was favorable for the migration and accumulation of salty deposit. When the precipitation was lower than 1 000 mm, ephemera shrub increased at the same depth as that of the salty deposit. It is, therefore, deduced that the formation of the salty deposit was attributed mainly to the dry and hot environment in the high mountains and deep basins. The small annual precipitation and the intense fluctuation are favorable for the sustainable accumulation of the salts, which is different from the present salty accumulation in the Northwest China. | Tong Guobang Liu Zhiming Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Zhengding 050803 Open Laboratory of Saline Lake Resources and Environment, Chinese Academy of Geological Sciences, Beijing 100037 Zheng Mianping Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037 Research & Development Center of Saline Lake and Epithermal Deposit, Chinese Academy of Geological Sciences, Beijing 100037 Wang Weiming Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008 | 2002 | Journal of China University of Geosciences2002，13，3： | 5 |
| 8 | Groundwater Systems and Eco-hydrological Features in the Main Karst Regions of China显示文摘Different karst water features and related water resources are present both in southern and northern China.There are over 3,358 well-developed karst ground river systems with total discharges in the dry season of about 420×108 m3 in the main karst regions in the southern part of China.Exploitation rates are only 8-15%.Over 100 larger karst spring systems in the main karst regions of northern China cover a catchment area from 500 km2 to over 4,000 km2,of which the average discharge appears to be from about 1 m3/s to 13 m3/s and the exploitation rates are 70-80%.Six aspects of the eco-hydrological features of some typical karst regions in China comprising water environment,ecological features,materials and structures between parent rock and soil,bio-geological processes and palynological studies(spore-pollen)are discussed.Qualitative evaluation of eco-geology and rocky desertification in the karst regions should be based on the main karst ecological conditions as well as artificial,i.e.,man-made impacts. | LU Yaoru ZHANG Feng'e LIU Changli TONG Guobang ZHANG Yun | 2006 | Acta Geologica Sinica(English Edition)2006，80，5： | 3 |
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