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Miocene Bahean stratigraphy in the Longzhong Basin, northern central china and its implications in environmental {2.

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Science china Earth Sciences 2006年第12期49卷 1270-1279页

作者： LI Jijun1,2. ZHANG Jun1, SONG Chunhui1, ZHAO Zhijun2. ZHANG Yong1, WANG Xiuxi 1, ZHANG Jianming1 & CUI Qiaoyu1 1. key laboratory of Western{2.’s environmental Systems (Ministry of Education) & college of Earth and Environment Sciences, Lanzhou university, Lanzhou 730000,{2. 2. jiangsu key laboratory of environmental change and ecological construction & college of geography, nanjing normal university, nanjing 2.0097,{2. key laboratory of Western{2.’s environmental Systems (Ministry of Education) & college of Earth and Environment Sciences Lanzhou University Lanzhou China jiangsu key {2. of environmental change and ecological construction & college of geography Nanjing Normal University Nanjing China

Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui, Gansu Province, northern central china. Hipparion weihoense, a typical member of late Middle Miocene Bahean stage, was recently excavated at Yaodian along a well-exposed outcrop. Owing to the importance of the Bahean stage in the mammalian evolution and its potential for environmental {2., we suggested a name of Yaodian Formation for the stratigra- phy, which is correlated to the Bahe Formation at Lantian, Shaanxi. High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 11.67 Ma and 7.43 Ma, with the site bearing Hipparion weihoense being estimated at about 10.54―10.30 Ma, providing first magnetostratigraphic chronology for the Bahean Stage. The Yaodian Formation consists of fluvial channel deposits (11.67―10.40 Ma) at the bottom, floodplain deposits in the middle (10.40―9.2. Ma) and shallow lake sediments at the top (9.2.―7.43 Ma). This upward fining sequence suggests that the relief in nearby mountain ranges such as West Qinling to the south and Huajia Ling to the north was greatly reduced after long-term denudation, fluvial transport capacity was low, and finally the drainage system was disintegrated, replaced with broad-shallow lakes in which only fine sediments like mud and marlite were deposited, indicating an old stage of development of a planation surface. A remarkable shift in ecology and climatic environment was found at 7.4―7.7 Ma when paleoclimate {2.d from early warm humid to late dry as indicated by sedimentary facies {2.d from early shallow lake sequence to late eolian red clays and a former coniferous-deciduous mixed forest was replaced by grassland, leading to great growth of Hipparion Fauna of Baodean stage in the region. Therefore, it is estimated that the present high relief of Qinling and drainage pattern did not come into being until Late Pliocene in response

关键词： Bahean stage,magnetostratigraphy,Yaodian Formation,Neogene,Longzhong Basin.

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A possible Younger Dryas-type event during Asian monsoonal Termination 3

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Science china Earth Sciences 2006年第9期49卷 982-990页

作者： CHEN Shitao1, WANG Yongjin1, KONG Xinggong1, LIU Dianbing1, CHENG Hai2.& R.L. Edwards2.1. college of geography Science,{2., jiangsu key laboratory of environmental change and ecological construction, nanjing 2.0097, china 2. Department of Geology and Geophysics, {12. of Minnesota, Minneapolis MN55455, USA college of geography Science Nanjing Normal University Jiangsu Key Laboratory of Environmental Change and Ecological Construction Nanjing China Department of Geology and Geophysics University of Minnesota Minneapolis USA

Seven U-Th dates, 560 δ 18O data and microscopic sequences were measured for sta- lagmites from two high-altitude caves in Shennongjia area, Hubei Province. Variations of the de- cadal-resolution stalagmite δ 18O record from Swan Cave (1600 m elevation) reflect large spatial changes in circulation strength and precipitation of Asian monsoon. The evidence comes from a great similarity among the stalagmite δ 18O records from nanjing, {2. Province; Libo, Guizhou Province and here studied area during the last deglaciation, including a part interval of Younger-Dryas event and Bolling-Allerod. A 30-year-resolution stalagmite δ 18O record from Yongxing Cave (1400 m eleva- tion), 70 km away from Swan Cave, reveals a rapid transition of Asian monsoon climate during Ter- mination 3 at about 2.5±5 kaBP. Based on 3 U-Th dates and about 5000 continuous annual bands, a millennial dry episode has been observed during Asian monsoonal Termination 3 from the Yongxing δ 18O profile. With respect to its structure, duration and transition, the dry reversal, as indicated by our stalagmite δ 18O record, generally agrees with the pattern of the YD event well-expressed in the Chi- nese stalagmite δ 18O records. This YD-type event is characterized by a large decrease in δ 18O value as much as 2.30‰, more than half of the δ 18O excursion between glacial/interglacial periods, and lasts 1371±59 a determined by the annual counting chronology. After this event, the monsoon climate shifted abruptly into the interglacial period within 74±4 a. Our data corroborate the view that the re- peated occurrence of YD-type event was not an “accident”, possibly resulted from the coupling of ice-sheet and oceanic/atmospheric circulations.

关键词： stalagmite, Termination 3, Asian monsoon, YD-type event, Shennongjia, Hubei Province.

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Study on Water Consumption Coefficient of People's Living and Its Regional Disparity in the North of china

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Chinese Journal of Population,Resources and Environment 2005年第2期3卷 20-26页

作者： Wang Jing’ai 1-3, Mao Rui 3,4, Yang Mingchuan 3,4 & Zhou Junju 11 college of geography & Remote Sensing 2.{2. laboratory of Regional geography of Beijing normal university 3 {2. laboratory of environmental change and Natural Disaster of Ministry of Education of china 4 college of Resources Science & Technology, Beijing normal university, Beijing 100875, china college of geography and Remote Sensing Beijing 100048 China key laboratory of {2. change and Natural Disaster of Ministry of Education of china Beijing 100048 China college of Resources Science and Technology Beijing Normal University Beijing 100875 China

By employing the information-reshufflingmethod that integrates census data, precipitation dataand inquiry data of water consumption, this paperdiscusses 5 (water consumption coefficient of people’sliving) in allusion to different precipitation zones anddifferent periods of time. The study shows that 5-(water consumption coefficient of urban people’sliving), 5. (water consumption coefficient of ruralpeople’s living) and increase with time passing, andthe increasing extent of 5 is 1.84, 2.62. 2.84 and 2.68times respectively from the west to the east, whichresults from the total quantity of water resources andthe speed of urbanization. 5- and 5. of eachprecipitation zone increased with 5- increasing morequickly than 5., and the difference between the twoalso increased when time passed. In the past fifty years(1950-2.00), the increasing extent of 5- was 1.71,2.96, 2.41 and 2.33 times respectively from the westto the east, in which 2.0-400mm precipitation zoneincreased more than others. Meanwhile the increasingextent of 5. is 1.55, 1.60, 1.53 and 1.64 timesrespectively from the west to the east with eachprecipitation zone increasing similarly. The change of5-is due to the speed of urbanization and the stabilityof water resources. This study provides basis forcalculating the water demand of people’s living andrevealing the impact of water demand of people’s livingon ecological drought in different zones.

关键词： The north of china precipitation zone water consumption coefficient of people’s living

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Pollen assemblages from different agricultural units and their spatial distribution in Anyang area

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Chinese Science Bulletin 2010年第6期55卷 544-554页

作者： WANG XueLi1,2.LI YueCong1,2.XU QingHai1,2.CAO XianYong1,2.ZHANG LiYan1,2.& TIAN Fang1,2.1 college of Resource and environmental Sciences,Hebei {2. university,Shijiazhuang 050016,china 2.Hebei key laboratory of environmental change and ecological construction,Shijiazhuang 050016,china college of Resource and environmental Sciences Hebei Normal University Shijiazhuang China Hebei key laboratory of {2. change and ecological construction Shijiazhuang China

Pollen analysis is one of the best and possible approaches for the quantitative reconstruction of paleobotany and paleoclimate,and discrimination of human *** this paper,we reveal the characteristics of pollen assemblages in different agricultural units and their spatial distribution of major pollen taxa in the Anyang area where the human influences are serious,so as to get more information about climate change and human activities from pollen *** pollen assemblages of total 12. surface soil samples from different agricultural units (farm lands,vegetable plots,wastelands,cape-lands,woodlands,etc.) indicate that herbaceous pollen dominates the pollen assemblages with an average of 73%,mainly from Poaceae,Artemisia,Chenopodiaceae and Cruciferae;arboreal pollen percentages reach 18%,mainly from Pinus and Ulmus;shrub pollen and fern spores have very low *** general,pollen assemblages are consistent with vegetation composition,though some differences also exist in different agricultural *** farmlands and vegetable lands,Poaceae pollen has the highest percentages (averaging 2.%) compared to other agricultural units with dominant corn or wheat pollen,while in wastelands and woodlands,arboreal and Artemisia pollen percentages have higher values (averaging 2.% and 19% respectively).Cruciferae has the highest pollen percentages (70%) in *** pollen assemblages and PCoA can generally identify the vegetable plots,farmlands,woodlands,wastelands,and *** and Artemisia pollens mainly appear in the western part of Anyang,which is consistent with the parent plants;Poaceae pollen mainly exist in the eastern part with more farmlands;Chenopodiaceae pollen mainly appear in the urban areas and near major roads where human influences are stronger,Cruciferae pollen can mainly be found in the urban area and in the northwest part of Anyang where more vegetables are planted.

关键词：安阳地区空间分布花粉组合单位农业

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Effect of water turbidity caused by suspended sands on Potamogeton crispus

Effect of water turbidity caused by suspended sands on Potam...

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International Symposium on Green Technology and Ecosystem Health

作者： Wen Teng Wang Guoxiang Qiang Li jiangsu key {2. of environmental change and ecological construction college of Geographical Science nanjing normal university nanjing {12. china

＜正＞Turions of Potamogeton crispus were planted in ponds with different turbidities （30NTU, 60NTU, 90NTU, 12.NTU, 150NTU）. The turbidity was caused by suspended sands （less than 100 μm in diameter）. To determin... 详细信息

关键词： sands water turbidity Potamogeton crispus photosynthetic chlorophyll characteristic.

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Effect of submerged plant Potamogeton crispus on the concentrations of phosphorus fractions in overlying water

Effect of submerged plant Potamogeton crispus on the concent...

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2.10 IEEE 2.d Symposium on Web Society

作者： Lizhi Wang Guoxiang Wang Zhenfei Yu Xiankun Gu Qiumin Chen college of Geographical Science,nanjing {2. university jiangsu key laboratory of environmental change and ecological construction nanjing{12.

＜正＞The effect of submerged plant *** on the concentrations of phosphorus（P） fractions in overlying water and seasonal variation were investigated under simulating *** growth and decomposition of *** were *** mechanism of the P exchange at sediment-water interface in shallow lake was elucidated *** results indicated that dissolved total P（DTP） was the dominated P fraction in the overlying water in the *** P（TP）, DTP,paniculate P（PP）,dissolved organic P（DOP）, soluble reactive P（SRP） were decreased and maintained in a low level during the growth period of *** P fractions ranged between 0.02.and 0.08mg/l during growth period of *** was the dominated P fraction in the overlying water in the decomposition period of *** average proportion of SRP to TP was 62.37%in the decomposition period.

关键词： Potamogeton crispus phosphorus overlying water

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Fractionation of Heavy Metals in Sediments from Dianchi Lake,china

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Pedosphere 2007年第2期17卷 265-272页

作者： LI Ren-Ying YANG Hao ZHOU Zhi-Gao Lü Jun-Jie SHAO Xiao-Hua JIN Feng State key laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. college of geography Science Nanjing Normal University Nanjing 210097 （China） Department of Applied Meteorology Nanjing University of Information Science ＆ Technology Nanjing 210044 （China）

Fractionation of heavy metals in sediments can help in understanding potential hazards of heavy metals. The present study analyzed total concentrations and fractions of selected heavy metals （Cd, Cr, Cu, Pb, and Zn） in surface sediments from Dianchi Lake, Yunnan Province, china, as well as factors that may affect distributions of the various heavy metal fractions. Total concentrations of the heavy metals decreased in the order Zn 〉 Cu 〉 Pb 〉 Cr 〉 Cd. These heavy metals, except Cr, were much higher than their background levels, indicating that Dianchi Lake was polluted by Cd, Zn, Pb, and Cu. Cadmium occurred mainly as the non-residual fraction （sum of the HOAc-soluble, reducible, and oxidizable fractions）（97.6%）, and Zn （55.7%） was also predominantly found in the non-residual fraction. In contrast, most of the Cr （88.5%）, Pb （81.8%）, and Cu （59.2.） occurred in the residual fraction. Correlation analysis showed that total heavy metal concentrations, organic matter and reducible Fe were the main factors affecting the distributions of the various heavy metal fractions. In the Walhai section of Dianchi Lake （comprising 97% of the lake area）, the concentrations of Cd, Zn, Pb, and Cu in the non-residual fraction were significantly lower （P ≤ 0.01 or 0.05） than those of the Caohal section （3% of the lake area）. This indicated that potential heavy metal hazards in the Caohai section were greater than the Waihai section.

关键词： Dianchi Lake heavy metal fractions lake sediment organic matter reducible Fe

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Pollen assemblage characteristics of lakes in the monsoon fringe area of china

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Chinese Science Bulletin 2008年第4期53卷 3354-3363页

作者： TIAN Fang1,2.XU QingHai1,2.3,LI YueCong1,2.CAO XianYong1,2.WANG XueLi1,2.& ZHANG LiYan1,2.1 college of Resources and environmental Sciences,Hebei {2. university,Shijiazhuang 050016,china 2.Hebei key laboratory of environmental change and ecological construction,Shijiazhuang 050016,china 3 key laboratory of Western china’s environmental System(Ministry of Education),Lanzhou university,Lanzhou 730000,china college of Resources and environmental Sciences Hebei Normal University Shijiazhuang China Hebei key laboratory of {2. change and ecological construction Shijiazhuang China key laboratory of Western{2.’s environmental System (Ministry of Education) Lanzhou University Lanzhou China

This paper presents the pollen assemblages from 108 surface sediment samples from 4 lakes(the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao) in the monsoon fringe area of *** herb pollen taxa Artemisia,Chenopodiaceae,Poaceae and Compositae are the major components of pollen assemblages of the 4 lakes and Pinus,Betula,Quercus,Ulmus,Populus,Ostryopsis and Elaeagnaceae are frequently presented,which reflect regional and local vegetation *** mean similarity coefficients for samples from the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao are 0.66 ± 0.17,0.71 ± 0.11,0.73 ± 0.12.and 0.67 ± 0.12.respectively,so pollen assemblages are relatively consistent in each lake,which shows that focusing and mixing effects have occurred before and after pollen ***,pollen assemblages do differ between sampling sites in each *** largest difference is seen in the Lake Daihai,followed by the Lake Duikounao,Lake Hulunnao and Lake Hongjiannao(The mean Euclidean distance is 2..09 ± 11.11,11.2. ± 3.64,10.67 ± 4.03 and 8.44 ± 4.51 respectively).These differences are possibly caused by the differences of focusing and mixing effects,pollen source areas,drainage areas and regional vegetation *** Lake Daihai and Lake Hongjiannao have water deeper than 5 m and strong re-suspension,focusing and mixing effects occur in the lakeshore and shallow water areas,where pollen concentrations are lower than in deeper lake *** the Lake Hulunnao and Lake Duikounao,with depths less than 5 m,re-suspension and mixing effects are obvious across the whole lake area,so pollen assemblages and pollen concentra-tions are more consistent among sampling sites in each *** between the lake samples and samples from the inflowing river reveals that wind is primary pollen transportation force in the Lake Hongjiannao,where the consistency of pollen assemblage is conspicuous,while there is greater variation in lakes where pollen input is

关键词：湖泊花粉相似系数欧几里得季风

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The Glacier Area changes in the Qangtang Plateau Based on the Multi-temporal Grid Method and its Sensitivity to Climate change

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Journal of Mountain Science 2011年第6期8卷 882-893页

作者： WANG Liping XIE Zichu WANG Xin LIU Shiyin DING Liangfu SHANGGUAN Donghui The college of Resources and environmental Science Hunan Normal University Changsha China Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Department of geography Hunan University of Science and Technology Xiangtan China

Glacier area changes in the Qangtang Plateau are analyzed during 1970-2.00 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid *** results indicate that the melting of glaciers accelerated,only a few of glaciers in an advancing state during 1970-2.00 in the whole Qangtang ***,the glaciers seemed still more stable in the study area than in most areas of western *** estimate that glacier retreat was likely due to air temperature warming during 1970-2.00 in the Qangtang ***,the functional model of glacier system is applied to study climate sensitivity of glacier area changes,which indicates that glacier lifespan mainly depends on the heating rate,secondly the precipitation,and precipitation increasing can slow down glacier retreat and make glacier lifespan prolonged.

关键词： The Qangtang Plateau Glacier change Multi-temporal Climate change Functional model ofglacier system Simulation

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水位变化对三峡库区低位狗牙根种群的影响

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生态环境学报 2010年第3期19卷 652-656页

作者：李强丁武泉朱启红宋力曹优明蒋山泉江苏省环境演变及生态建设重点实验室江苏南京210097 重庆文理学院化学与环境工程学院重庆永川402160

2.09年调查研究了三峡库区长寿段消落带的狗牙根(Cynodon dactylonL.)种群,探讨了库区水位变化对低位狗牙根种群的影响。结果表明,156m处狗牙根地下茎的总茎长、总茎节数和总茎节数/总茎长大于150m处的狗牙根,分别比后者多2..3%、30.1%... 详细信息

2.09年调查研究了三峡库区长寿段消落带的狗牙根(Cynodon dactylonL.)种群,探讨了库区水位变化对低位狗牙根种群的影响。结果表明,156m处狗牙根地下茎的总茎长、总茎节数和总茎节数/总茎长大于150m处的狗牙根,分别比后者多2..3%、30.1%、11.3%;而其地下茎的总芽数/总茎长、萌芽数和萌芽率分别比后者低7.5%、34.3%、74.9%。同时,156m处狗牙根分株的株数、茎长、叶宽、叶长低于150m处的狗牙根,分别比后者少了2..2.、10.8%、19.0%、37.9%;其茎节数、茎节数/茎长、叶片数、根长较大,分别比后者增加了18.7%、34.2.、10.0%、2..6%。156m处狗牙根植株分株的鲜质量、干质量、鲜质量/总鲜质量、干质量/总干质量分别比150m处的狗牙根低32.5%、13.2.、18.2.和14.2.;其地下茎的鲜质量、干质量、鲜质量/总鲜质量、干质量/总干质量分别比后者高5.8%、17.5%、2..2.、15.2.;且前者的分株、地下茎和根的干鲜质量比均分别比后者高2..6%、12.5%和17.6%。表明,库区水位变化显著促进了150m处狗牙根地下茎茎节伸长、芽形成、芽萌发和分株的生长。因而,低位狗牙根对库区水位变化具有较强的适应能力。

关键词：三峡水库蓄水水位消落带狗牙根

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