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New data regarding acritarch biostratigraphy from the Early-Middle Cambrian Kaili Formation in Chuandong,Guizhou Province,china

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Progress in Natural Science:Materials International 2009年第1期19卷 107-114页

作者： Leiming Yin a,Ruidong Yang b,Jin Peng c,Fanfan Kong a a nanjing institute of Geology and Palaeontology,chinese academy of {4.,nanjing 2.0008,china b College of Resource and Environment of Guizhou University,Guiyang 550003,china c Department of {4. of nanjing University,nanjing 210093,china [a]nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China [b]College of Resource and Environment of Guizhou University Guiyang 550003 China [c]Department of Sciences of Nanjing University Nanjing 210093 China

Previous studies had evaluated acritarchs from the Balang and Pingzhai sections of the Early-Middle Cambrian Kaili Formation in east Guizhou,*** results of these studies suggest that the acritarchs in these sections have potential biostratigraphic *** recently,34.samples collected from 83 m lower part of the Lower-Middle Cambrian Kaili Formation in the Jianshan section of Chuandong,Guizhou Province were prepared for palynological *** of these samples revealed a distinct change in the acritarch assemblages at the bed,which was approximately 4. m above the bottom of the Kaili *** findings suggest a boundary represented by an important alteration of the ecological *** addition,the position of the acritarch biostratigraphic change is somewhat higher than the boundary between Cambrian Series 2 and Series 3 based on trilobites found in the same *** indicates that the distinct change in acritarch assemblages is similar to the change in trilobite assemblages that occurs around the boundary between Cambrian Series 2 and Series ***,acritarch biostratigraphy can provide data that can be used to define the base of Cambrian Series 3 in this region,and possibly worldwide.

关键词： Acritarchs Lower-Middle Cambrian Kaili Formation Jianshan section Chuandong

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Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science china Earth sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2, MIAO Qilong1 & YU Qiang2 1. Department of geography, nanjing institute of Meteorology, nanjing 21004.,{4. 2. institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101,{4. nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 4.2 weather stations and 512 hydrological stations in china, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

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Pollen records of Holocene vegetation and climate changes in the Longzhong Basin of the chinese Loess Plateau

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Progress in Natural Science:Materials International 2007年第12期17卷 1445-1456页

作者： Tang Lingyu1 and An Chengbang2(1. nanjing institute of Geology and Paleontology, chinese academy of sciences, nanjing {4., china 2. Key Laboratory of Western china’s Environment Systems, MOE, Lanzhou University, Lanzhou 730000, china) nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Key Laboratory of Western china’s Environment Systems MOE Lanzhou University Lanzhou 730000 China

Pollen records with an average time resolution of 20-200 years from Holocene loess sections at Dingxi, Qin'an, and other localities of Gansu Province reveal a detailed history of vegetation and climate changes in the western Loess Plateau. For most time of the Holocene, the landscape was dominated by grasslands or forest steppes. However, during the middle Holocene (7.5-5.8 ka BP), relatively dense forests developed, and the endemic vegetation flourished, suggesting a much warmer and more humid climate condition than the present. Superimposed upon this general pattern are several dry intervals marked by the episodic expansion of grasslands or forest steppe. Xeric vegetation expanded after 3.8 ka BP, indicating a trend towards dry conditions.

关键词： pollen records glasslands coniferous forests Holocene Loess Plateau.

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Sustainable Nutrient Management in chinese Agriculture: Challenges and Perspective

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Pedosphere 2006年第2期16卷 253-263页

作者： GAO Chao SUN Bo ZHANG Tao-Lin Department of geography Nanjing University Nanjing 210093 （China）. institute of Soil Science Chinese Academy of Sciences Nanjing 2100（78 （China）

china has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented.

关键词： china food security nutrient management soil fertility water quality

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An XPS Study of Nitrogen Structures in Soil Humic Substances

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Pedosphere 2001年第4期11卷 321-326页

作者： WEN QIXIAO, CHENG LILI and CHEN BIYUN institute of Soil Science, the chinese academy of sciences, nanjing 2.0008 ({4.) institute of Soil Science the Chinese Academy of Sciences Nanjing 210008 China

X-ray photoelectron spectroscopy (XPS) was applied to examine the N structures of soil humic substances and some of their analogues. It was found that for soil humic substances XPS method gave similar results as those obtained by 15N CPMAS NMR (cross-polarization magic-angle spinning nuclear magnetic resonance) method. 70%～86% of total N in soil humic substances was in the form of amide, and 6%～13% was presented as amines, with the remaining part as heterocyclic N. There was no difference in the distribution of the forms of N between the humic substances from soils formed over hundreds or thousands of years and the newly formed ones. For fulvic acid from weathered coal and benzoqu inone- (N H-4.)-2 S O-4.polymer the XPS results deviated significantly from the 15N CPMAS NMR data.

关键词： distribution of N forms 15N CPMAS NMR soil humic substances XPS.

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Late Jurassic and Early Cretaceous Radiolarians from Zhilong,Gyangse,Tibet

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地学前缘 2009年第S1期16卷 275-276页

作者： Bo Xu,Hui Luo nanjing institute of Geology and Palaeontology,chinese academy of {4.,nanjing 2.0008,china.

Abundant well-preserved Late Jurassic-Early Cretaceous radiolarian fossils were extracted from 31 bedded green chert samples collected from Zhilong section,Gyangse,southern ***

关键词： Late Jurassic Early Cretaceous radiolarians Zhilong Gyangse Tibet

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Multiple Effects of Energy Issues and Countermeasures: A Case of Shandong Province

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chinese Journal of Population,Resources and Environment 2008年第4期6卷 88-94页

作者： Wang Chengxin1,2 , Wang Gefang3 , Yao Shimou4.1. College of Population, Resources and Environment, Shandong Normal University, Jinan Shandong 250014. china 2. Research Center of Cycle Economy of Shandong Province, Jinan Shandong 250001, china 3. Party School of the Shandong Committee of CPC, Jinan Shandong 250021, china 4. nanjing institute of geography and limnology,{4., nanjing jiangsu 2.0008, china College of Population Resources and Environment Shandong Normal University Research Center of Cycle Economy of Shandong Province Party School of the Shandong Committee of CPC nanjing institute of geography and limnology Chinese Academy of Sciences

Energy is now becoming the bottleneck of urban and regional development. The paper takes Shandong Province, one of the most energy consuming provinces in china, as an example, uses quantity methods such as SPSS (Stastics Package for Social Science) cluster sampling and regression analysis, and applies quantity analysis, to analyze the situation of energy issues in Shandong province. The conflicts between the quick industrialization and increasing extensive economic development, between urban population and energy consuming per head, between the infinite energy consuming desire and the low level of managing system, and between the unstable world energy supply and the limited energy storage in china are the main factors of energy crisis in Shandong, which not only results in energy shortage, but also becomes the barrier of economic and social development. In order to ensure sufficient energy supply for Shandong province in the 21st century, we should take countermeasures, such as changing the economic development model, pursuing a multiple and high quality energy strategy, improving the intensive urbanization strategy, and building a scientific energy system.

关键词： energy effects countermeasure Shandong Province

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A Simulation Study on Effect of Surface Film-Forming Material on Water Evaporation

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Pedosphere 2001年第1期11卷 67-72页

作者： ZHUANG SHUNYAO, YIN BIN and ZHU ZHAOLIANG (institute of Soil Science, the chinese academy of sciences, nanjing 2.0008 ({4.)) 中科院南京土壤所江苏南京 210008

A greenhouse experiment was conducted to investigate the effect of surface film-forming material (SFFM), a mixture of 16-18-octadecanols by emulsification, on water evaporation. Air-dried soil with distilled water was incubated firstly for 7 days to reestablish soil biological activity and then for another 7 days after treated with SFFM at rates of 0, 1, 2, 4. 6 and 8 g m-2, respectively. Everyday during the 7-day incubation after addition of SFFM, water losses due to evaporation were ~measured by an electronic balance. The rate of water evaporation with the addition of SFFM was reduced significantly compared with the control treatment and the effectiveness of SFFM on water evaporation reduced with time. According to the equation expressions of the effect of SFFM on water evaporation, the half-life of electiveness of SFFM on water evaporation was introduced and calculated to analyze quantitative relationship between the effectiveness of SFFM on water evaporation and the addition rate of SFFM. The calculated half-life increased with the addition rate of SFFM and the confidence of the calculated values of the half-life was high, suggesting that the half-life of effectiveness of SFFM on water evaporation could be described quantitatively and may be helpful for ameliorating application method of SFFM and screening surface-film forming materials in order to improve nitrogen fertilizer use efficiency in flooded rice fields.

关键词： half-life of effectiveness surface film-forming material water evaporation

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Nitrogen Mineralization of Prunings of Six N_2-Fixing Hedgerow Species in a Dry Valley of the Jinsha River

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Pedosphere 2002年第1期12卷 25-31页

作者： SUN HUI, TANG YA and ZHAO QIGUO institute of Soil Science, the chinese academy of sciences, nanjing, 2.0008 ({4.) Chengdu institute of Biology, the chinese academy of sciences, Chengdu 61004. ({4.) institute of Soil Science the Chinese Academy of Sciences Chengdu 610041 Ghengdu institute of Biology the Chinese Academy of Sciences Chengdu 610041 institute of Soil Science the Chinese Academy of Sciences Nanjing 210008

A litterbag experiment of 12 weeks was conducted to study nitrogenmineralization process of prunings of six nitrogen-fixing hedgerowspecies in a dry valley of the Jinsha River. Prunigns wereincorporated into soil or used as mulch. The results indicated thatpruning N of the six hedgerow species was mineralized fast in thefirst week and then decreased slowly in the rest of the study *** prunings were incorporated into soil, the amount of nitrogenmineralized by the end of the first week accounted for 69.9/100,58.2/100, 54.5/100, 4..0/100, 29.6/100 and 20.6/100 of the total N inprungins of Desmodium rensonii, Tephrosia candida, Leucaenaleucoephala, Albizia yunnanensis, Acacia dealbata, and Acaciamearnsii, respectively.

关键词： contour hedgerow system mineralization N, prunings

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Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2 and Luo Zhexian2(1. institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029, china 2. nanjing University of Information {4. & Technology, nanjing 21004., china) institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China nanjing University of Information sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 1200 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

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