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Research on the evaluation model of the modernization level of urban construction in Jiangsu Province,china

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science china(Technological sciences) 2010年第9期53卷 2510-2514页

作者： YANG JunYan1 & CHEN Wen2 1 School of Architecture,Southeast University,nanjing 210096,china 2 nanjing {3. of Geography and Limnology,chinese academy of sciences,nanjing 210008,china School of Architecture Southeast University Nanjing China nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing China

The modernization of urban construction is a key index in the process of urbanization,and also is an important index to measure the level of socio-economic and cultural *** paper analyzes and explores the related concepts of modernization of urban construction,analyzes the situation and identity of urban construction layer by layer so as to establish an evaluation index system of the modernization level of urban construction and then the paper evaluates the modernization level of urban construction from four different angles,which are the perspectives of the urban planning control,the level of urban facilities,urban management,urban construction *** later analyzes the evaluation results by choosing Jiangsu Province as a research hierarchy from the scale chains of urban study and makes efforts to the operative and directive development direction.

关键词： modernization of urban construction index system evaluation model

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,{3., china 2. Key Laboratory of Western china’s Environment Systems, MOE, Lanzhou University, Lanzhou 73.000, 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.

Nutrient fluxes induced by disturbance in Meiliang Bay of Lake Taihu

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science china Earth sciences 2006年第z1期49卷 186-192页

作者： LUO Liancong, QIN Boqiang, ZHU Guangwei, SUN Xiaojing, HONG Dalin, GAO Yajun & XIE Rui nanjing institute of Geography & Limnology, chinese academy of sciences,{3., china nanjing Hydraulic Research institute, Ministry of Water Resources, nanjing 210024, china nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing China nanjing Hydraulic Research institute Ministry of Water Resources Nanjing China

A wave flume experiment was conducted to study nutrient fluxes at water-sediment interface of Meiliang Bay under different hydrodynamic conditions. The results reveal that hydrodynamics has remarkable effects on nutrient fluxes in this area. With a bottom wave stress of 0.019 N m-2 (equivalent to disturbance caused by wind SE 5-7 m s-1 at the sediment sample site of Meiliang Bay), the fluxes of TN, TDN and NH4+-N were separately 1.92× 10-3. -1.81 × 10-4 and 5.28× 10-4 mg m-2 s-1(positive for upward and negative for downward), but for TP, TDP and SRP, the fluxes were 5.69 × 10-4, 1.68 × 10-4 and -1.29 × 10-4 mgm-2 s-1. In order to calculate the released amount of nutrients based on these results, statistic analysis on the long-term meteorological data was *** result shows that the maximum lasting time for wind SE 5-7 m s-1 in this area is about 15 h in summer. Further calculation shows that 111 t TN, 3. t NH4+-N, 3. t TP and 10 t TDP can be released into water (the sediment area was 47.45% of the whole surface area), resulting in concentration increase of 0.025, 0.007, 0.007 and 0.002 mg L-1 separately. With stronger disturbance (bottom wave stress is 0.217 N m-2 which is equivalent to disturbance caused by wind SE 10-11 m s-1 at the same site), there has been significant increase of nutrient fluxes (1.16× 10-2, 6.76×10-3. 1.14× 10-2 and 2.14× 10-3.mgm-2 s-1 for TN, DTN and NH4+-N and TP). The exceptions were TDP with flux having a decrease (measured to be 9.54× 10-5 mgm-2 s-1 ) and SRP with flux having a small increase (measured to be 5.42 × 10-5 mgm-2 s-1). The same statistic analysis on meteorological data reveal that the maximum lasting time for wind SE 10-11 m s-1 is no more than 5 h. Based on the nutrient fluxes and the wind lasting-time, similar calculations were also made suggesting that 23. t TN, 13..9 t TDN, 228 t NH4+-N, 42.7 t TP, 2.0 t TDP and 1.1 t SRP will be released from sediment at this hydrodynamic condition resulting in the concentration

关键词： hydrodynamics disturbance water-sediment interface nutrient release flux Lake Talhu.

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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science china Earth sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3.1 State Key Laboratory of Palaeobiology and Stratigraphy,nanjing institute of Geology and Palaeontology,chinese {3. of sciences,nanjing 210008,china 2 Graduate School of chinese academy of sciences,Beijing 100049,china 3.Department of science and Technology,Bryant University,Smithfield RI 02917,USA State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Graduate School of chinese academy of sciences Beijing China Department of science and Technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

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 {3. of sciences,nanjing 210008,china.

Abundant well-preserved Late Jurassic-Early Cretaceous radiolarian fossils were extracted from 3. bedded green chert samples collected from Zhilong section,Gyangse,southern ***

关键词： Late Jurassic Early Cretaceous radiolarians Zhilong Gyangse Tibet

Evaluation of N2-Fixation Capacity of Leguminous Shrub Plants

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Pedosphere 2000年第2期10卷 159-163页

作者： SHI SHULIAN DU LIJUAN, CAO YACHENG and SUN GUOQING(institute of soil science, the{3., P.O. Box 821, nanjing 210008 china) 中科院南京土壤所江苏南京 210008

N2-fixation percentages in the aerial parts of the first and second cuttings of five species of leguminousshrub plants, i.e., Lespedeza formosa (Vog.) Koehne from Jiangxi, Lespedeza pllosa (Thunb.) Sieb et Zucc.,LesPedeza formosa (Vog.) Koehne from Zhejiang, Cajanus cajan (L.) Millsp. and Indigofera pseudotinctoriaMats., of three genera were investigated in terms of pot culture experiment using natural 15N abundancemethod with Bischofia javanica B1., Camptotheca acuminata Decne. and Gardenia jasminoides Ellis asreference plants. Results showed that the N2-fixation percentages were different for the three genera ofleguminous shrubs but almost the same for three species in the same genus. I. pseudotinctoma Mats. hadthe highest N2-fixation percentage in its aerial part, and then followed by Lespedeza and C. cajan. TheN2-fixation percentages in the aerial parts of the plants that had grown for three years tended to be lowerthan those of the onesyear-old plants except L. formosa (Vog.) Koehne from Zhejiang and L. formosa (Vog.)Koehne from Jiangxi.

关键词： leguminous shrub natural 15N abundance method N2-fixation percentage

Grey Disorder in Field Flue-Cured Tobacco

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Pedosphere 1999年第4期9卷 369-374页

作者： ZHANG XIN ZHAO QIBO YU HUIMEI CAO ZHIHONG(1institute of soil science, the{3., nanjing 210008 (china))(2Jiangsu Provincial Tobacco Company, nanjing 210O29 (china)) 中科院南京土壤所江苏南京 210008 江苏省烟草公司江苏南京中科院南京土壤所江苏南京

A field study was carried out on the grey disorder in fine-cured tobacco (Nicotiana tabacum L.) *** results showed that low Eh and high available Fe content in the soils were responsible for the grey tobaccoand dead roots. Grey disorder leaves produced low quality lamina, which was low in N, nicotine, reducedsugar and K contents. In this study’ soil available Mn and leaf Mn contents were in a relatively low level andshould not be an important factor in the occurrence of grey disorder in fine-cured tobacco.

关键词： flue-cured tobacco grey disorder iron manganese toxicity

soil Organic Carbon Storage in china

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Pedosphere 2004年第4期14卷 491-500页

作者： XIEXian-Li SUNBo ZHOUHui-Zhen LIAn-Bo instituteofsoilscience ChineseAcademyofSciencesNanjing210008（China）. GeographyCollege NanjingNormalUniversityNanjing210097（China）

soil organic carbon (SOC) storage under different types of vegetations in china were estimated using measured data of 2 440 soil profiles to compare SOC density distribution between different estimates, to map the soil organic carbon stocks under different types of vegetation in china, and to analyze the relationships between soil organic carbon stocks and environmental variables using stepwise regression analyses. soil organic carbon storage in china was estimated at 69.3. Gt (10 15 g). There was a big difference in SOC densities for various vegetation types, with SOC distribution closely related to climatic patterns in general. Stepwise regression analyses of SOC against environmental variables showed that SOC generally increased with increasing precipitation and elevation, while it decreased with increasing ***, the important factor controlling SOC accumulation for forests was elevation, while for temperate steppes mean annual temperature dominated. The more specific the vegetation type used in the regression analysis, the greater was the effect of environmental variables on SOC. However, compared to native vegetation, cultivation activities in the croplands reduced the influence of environmental variables on SOC.

关键词： china environmental factors soil organic carbon storage vegetation

APPLICATION　OF　GIS　IN　ANALYZING　ECOSYSTEM＇S　RELATIVE　SENSITIVITY　TO　ACID　DEPOSITION

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chinese Geographical science 1996年第4期6卷 359-363页

作者： He Longhua Yans Hongwei(nanjing institute of Geography & Limnology, the chinese academy of sciences,nanjing 210008, PRC) nanjing institute of Geography & Limnology the Chinese Academy of Sciences Nanjing PRC

This paper decribo an application of GIS technology in estimating estem's relive sensitivity to acid despition. East china is selected as the research area. Four variable layers, which are ha rock, soil buffering ability, vegetation type and soil humidity, are used in the process. Five grades are separated in this research. The sensitivity mapping is also discussed in this paper.

关键词： acid deposition sensitivity index geographic information system