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Tree　ring　analysis　for　determination　of　pollution　history　of　Chengde　City，north　china

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Journal of Environmental sciences 1996年第1期8卷 77-85页

作者： Jiang Gaoming(institute of botany, chinese academy of sciences,beijing 10004.,{4. ) Inst botany Chinese Acad of Sci Beijing China China

Air pollution history of sulphur and heavy metals since 1800 in Chengde City , north china,was studied by analyzing the concentrations of sulphur and heavy metals in growth rings of Pinus tabulaeformis Carr. Sulphur concentrations in the tree rings of 1910-1920, 1970-1980,and 1980-1990 have increased 1-2 , 3-5 and 10 times respectively as those in the tree ring of 1810-1820 (P4., possibly due to the opening of Damiao Iron Mine by the Japanese in 1927; Mn increased throughout the whole history, from 4. 1 μg/g(184.- 1850) to 10. 4.μg/g (1980 1990,P 4.1.8,1.5,1.0 and 0. 8 times respectively during the past 190 years or so. The results showed that serious environmental pollution, especially air pollution of SO2,has occurred since 194. when the People's Republic of china was founded.

关键词： tree rings Pinus tabulaeformis sulphur and heavy metals pollution history Chengde

Phosphatidylglycerol effect on oxygen-evolving activity in Ca^(2+)-depleted photosystem Ⅱ

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chinese Science Bulletin 2000年第21期45卷 1964-1968页

作者： YANG Zhenle, LI Liangbi, XU Yinong & KUANG TingyunLaboratory of Photosynthesis Basic Research, institute of botany, chinese academy of sciences, beijing 100093. china Laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of Sciences Beijing China

The ettect of anionic phosphatidylglycerol (HG) on oxygen evolution in a photosystem Ⅱ (PS Ⅱ) particle depleted of Ca2+ (designated dCaPS Ⅱ) has been investigated. The major finding is the observation of a new role of PG in the PS Ⅱ function. That is, PG restores nearly the lost oxygen evolution in dCaPS Ⅱ particle owing to Ca2+ depletion to the levels in intact PS Ⅱ . Furthermore, there is a stimulation of oxygen-evolving activity in the dCaPSⅡ complexed with PG in the presence of exogenous CaCI2, which PG enhances increasingly oxygen evolution with increasing CaCI2 concentration. It is suggested that PG-induced oxygen evolution recovery of dCa PS Ⅱresumption of normal structure in protein by PG effect, whereas the enhancement of oxygen evolution in complex subject to CaCI2 is ascribed to the optimization of such a structure due to coordination complex formation of Ca2+ ions with PG.

关键词： photosystem Ⅱ Ca2+-depleted photosystem Ⅱ phosphatidylglycerol Ca2+ oxygen-evolving activity.

Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

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Journal of Systematics and Evolution 2011年第6期49卷 539-545页

作者： 1,2Hong YAO 1Yi-Bo LUO 1(State Key Laboratory of Systematic and Evolutionary botany,institute of botany,chinese {4. of sciences,beijing 100093.china) 2(Graduate University of the chinese academy of sciences,beijing 10004.,china) (State Key Laboratory of Systematic and Evolutionary botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) *Correspondence: Yi-Bo LUO *Correspondence: E-mail: luoyb@*** Tel.: 86-10-62836514 Fax: 86-10-6259084..

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3-4.hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2 h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

Impact of changing atmospheric CO_2 concentrations over the Phanerozoic on stomatal parameters of vascular land plants

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chinese Science Bulletin 1999年第7期44卷 577-582页

作者： SUN Qigao, CHEN Liqun and LI Chengseninstitute of botany, chinese academy of sciences, beijing 100093. china, institute of botany Chinese Academy of Sciences Beijiing China

A novel and multi-disciplinary subject involving the relationships between changes in atmospheric CO2 concentration throughout the geological history and features of plant anatomy is reviewed. Particular attention will be given to stomatal parameters （stomatal density and stomatal index） which are recorded at a cellular level in fossil plants and the relationships of these observable parameters to earth life history and global environmental change. Trends of atmospheric CO2 concentrations during the Phanerozoic period are briefly introduced and recent conceptual advances in understanding the causal mechanisms for changes in stomatal parameters of land vascular plants are considered, In addition, some of the inherent problems and limitations of this kind of work are discussed and future research directions are presented.

关键词： Phanerozoic atmospheric CO2 concentrations vascular plants stomatal parameters.

Value of ecosystem services in china

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chinese Science Bulletin 2000年第10期45卷 870-876页

作者： CHEN Zhongxin & ZHANG XinshiLaboratory of Quantitative Vegetation Ecology, institute of botany, chinese academy of sciences, beijing 100093. china Current address: institute of Natural Resources and Regional Planning, chinese academy of Agricultural sciences, beijing 100081, china Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

The function and services are the important components of the life-support system in theplanet, as well as the basic elements for sustainable development of environment and society. It is a must to evaluate it for incorporating it with the social-economic system. It is also an important approach to draw the public attention on the environmental and ecosystem conservation. In this study, the ecosystem function and services in china were estimated by employing the classification and economic parameters from Costanza et al. The type and area of terrestrial ecosystems were extracted from Vegetation Map of china (1:4.000 000), and then the distribution map of ecosystem services of china was drawn. According to our calculation, the total value of ecosystem services in china is 77 834.4.×108 RMB yuan per annum. The value for terrestrial ecosystem is 56 098.4.×108 yuan per annum, and that for marine ecosystem is 21 736.02×108 yuan per annum. The value of ecosystem services in china is 1.73 times bigger

关键词： ecosystem function service.

Thermal stability of oxygen evolution in photosystem Ⅱ core complex in the presence of digalactosyl diacylglycerol

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chinese Science Bulletin 2002年第24期47卷 2089-2092页

作者： YANG Zhenle, LI Liangbi & KUANG TingyunPhotosynthesis Research Center, institute of botany, chinese academy of sciences, beijing 100093. china Photosynthesis Research Center Institute of Botany Chinese Academy of Sciences Beijing China

The influence of digalactosyldiacylglycerol (DGDG), one of the photosynthetic membrane lipids, on heat inactivation of the process of oxygen evolution has been studied in vitro in photosystem Ⅱ(PS Ⅱ) core complex. It was found that the temperature of semi-inactivation of oxygen evolution in the complex increased from 4..0 to about 4..0℃ in the presence of DGDG with 5-min heat treatment in the dark. Furthermore, when PS Ⅱ core complex was incubated for 5 min at 4..0℃, the oxygen evolution in the complex was completely lost, whilst the DGDG-complexed PS Ⅱ core complex still retained a 16% of activity (100% for 25.0℃). In addition, a 1-h incubation at 38.0℃ inactivated absolutely the oxygen evolution for the PS Ⅱ core complex. By contrast, there remained about 20% of activity (zero time for 100%) for the complex in the presence of DGDG under the same condition. These results indicate a new role of DGDG in the protection of PS Ⅱ core complex against the deleterious effects of temperature. It was

关键词： digalactosyl diacylglycerol photosystem Ⅱ core complex extrinsic protein of 33 kD thermal stability oxygen evolution.

Relation between artificial electron acceptors and heterogeneity of photosystem Ⅱ

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chinese Science Bulletin 1997年第18期42卷 1575-1578页

作者： WEN Xiaogang, LIN Shiqing and KUANG Tingyuninstitute of botany, chinese academy of sciences, beijing 100093. china institute of botany Chinese Academy of Sciences Beijing China

IN recent years, evidence has been accumulated for the existence of some photosystem Ⅱ(PS Ⅱ) reaction centers which are incapable of the electron transfer from Q_A to Q_B. These PSⅡ centers are called the inactive PSⅡ centers, compared with the normal ones which are called the active PSⅡ center. Two artificial electron acceptors, 2, 6-dichloro-p-benzoquinone (DCBQ) and 2, 5-dimethyl-p-benzoquinone (DMQ), were often used in studying the heterogeneity of the active and inactive PSⅡ centers. Some believed that DCBQ accepted the electron from both the active and inactive PSⅡ centers and DMQ only from the active PSⅡ cen-

关键词： DCBQ DMQ heterogeneity of PS Ⅱ chlorophyll fluorescence kinetics.

Terrestrial transect study on driving mechanism of vegetation changes

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Science china Earth sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1,2 & ZHOU GuangSheng1 1 State Key Laboratory of Vegetation and Environmental Change, institute of botany, chinese academy of sciences, beijing 100093. china 2 Graduate University of chinese academy of sciences, beijing 10004., china 1. State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

In terms of chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in china from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast china Transect (NECT) and the North-South Transect of Eastern china (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Present status and development on biological nitrogen fixation research in china

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chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang Key Laboratory of Photosynthesis and Plant-Environment MolecularPhysiology, institute of botany, chinese academy of sciences, beijing 100093. china Key Laboratory of Photosynthesis and Plant-Environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in china as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inchina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inchina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型