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Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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Science china(Technological sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4.& CHEN Jiayi4.1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, chinese academy of sciences, Beijing 100101, china 2. Research Center for Remote Sensing and GIS, Department of Geography, Beijing Normal {4., Beijing 100875, china 3. graduate {4. of chinese academy of sciences, Beijing 100039, china 4. Department of Atmospheric Physics, Peking {4., Beijing 100871, china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University Beijing 100875 China graduate university Chinese Academy of Sciences Beijing 100039 China Department of Atmospheric Physics Peking University Beijing 100871 China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Polyphyly of the fern family Tectariaceae sensu Ching:Insights from cpDNA sequence data

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Science china(Life sciences) 2007年第6期50卷 789-798页

作者： LIU HongMei1,2, ZHANG XianChun1, CHEN ZhiDuan1, DONG ShiYong3 & QIU YinLong4.1 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, chinese academy of sciences, Beijing 100093, china {4., Beijing 100039, china 3 South china Botanical Garden, chinese academy of sciences, Guangzhou 510650, china 4.Department of Ecology and Evolutionary Biology, university of Michigan, Ann Arbor, MI 4.109-104., USA State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing China graduate university of chinese academy of {4. Beijing China South china Botanical Garden Chinese Academy of Sciences Guangzhou China Department of Ecology and Evolutionary Biology University of Michigan Ann Arbor USA

Tectariaceae are a pantropical fern family of about 20 genera, among which 8 are distributed in china. The morphological distinctiveness of the family is widely recognized, yet relatively little systematic research has been conducted on members of Tectariaceae. Phylogenetic analyses of chloroplast DNA sequence data (rbcL; atpB) from 15 species representing all 8 genera in china were carried out under parsimony criteria; Bayesian inference. The phylogenetic reconstructions indicated that the fern family Tectariaceae as traditionally circumscribed are polyphyletic. Ctenitis, Dryopsis, Lastreopsis clustered with; should be included within the newly-defined Dryopteridaceae,; Pleocnemia is also tentatively assigned to it. A narrowly monophyletic Tectariaceae is identified, which includes Ctenitopsis, Hemigramma, Pteridrys, Quercifilix,; Tectaria. In the single rbcL analysis, Arthropteris clustered with the above-mentioned monophyletic Tectariaceae. Although further investigations are still needed to identify infrafamilial relationships within the monophyletic Tectariaceae; to redefine several problematic genera, we propose a working concept here that better reflects the inferred evolutionary history of this group.

关键词： Tectariaceae, polyphyly, rbcL, atpB

Validating global hydrological models by ground and space gravimetry

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chinese Science Bulletin 2009年第9期54卷 1534-1542页

作者： ZHOU JiangCun1,2,3, SUN HePing1,2 & XU JianQiao1,2 1 Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 4.0077, china 2 Key Laboratory of dynamic geodesy, chinese academy of sciences, Wuhan 4.0077, china 3 graduate university of chinese academy of sciences, Beijing 10004., china Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Key Laboratory of dynamic geodesy Chinese Academy of Sciences Wuhan China graduate university of chinese academy of {4. Beijing China

The long-term continuous gravity observations obtained by the superconducting gravimeters (SG) at seven globally-distributed stations are comprehensively analyzed. After removing the signals related to the Earth's tides and variations in the Earth's rotation, the gravity residuals are used to describe the seasonal fluctuations in gravity field. Meanwhile, the gravity changes due to the air pressure loading are theoretically modeled from the measurements of the local air pressure, and those due to land water and nontidal ocean loading are also calculated according to the corresponding numerical models. The numerical results show that the gravity changes due to both the air pressure and land water loading are as large as 100×10-9 m s-2 in magnitude, and about 10×10-9 m s-2 for those due to the nontidal ocean loading in the coastal area. On the other hand, the monthly-averaged gravity variations over the area surrounding the stations are derived from the spherical harmonic coefficients of the GRACE-recovered gravity fields, by using Gaussian smoothing technique in which the radius is set to be 600 km. Com-pared the land water induced gravity variations, the SG observations after removal of tides, polar mo-tion effects, air pressure and nontidal ocean loading effects and the GRACE-derived gravity variations with each other, it is inferred that both the ground- and space-based gravity observations can effec-tively detect the seasonal gravity variations with a magnitude of 100×10-9 m s-2 induced by the land water loading. This implies that high precision gravimetry is an effective technique to validate the re-liabilities of the hydrological models.

关键词：重力测量水文模型模型验证和空间地面重力变化季节性波动空气压力

Cloning,expression and characterization of a nucleoside diphosphate kinase (NDPK) gene from tobacco

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Progress in Natural Science:Materials International 2007年第8期17卷 906-912页

作者： Zhou Qiyun~(1,2**) Xie Zongming~(1**) Zhang Zhigang~1 Cao Yangrong~1 Zhang jinsong~(1***) Chen Shouyi~(1***) (1.National Key Laboratory of Plant Genomics,Institute of Genetics and Developmental Biology,chinese academy of sciences,Beijing100101,china 2.{4. university of chinese academy of sciences,Beijing 100039,china) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Acad. of Sci. Beijing 100101 China graduate university Chinese Acad. of Sci. Beijing 100039 China

Nucleoside diphosphate kinase (NDPK) is a housekeeping enzyme that maintains the intracellular levels of all (d)NTPs used in biosynthesis except *** we report that a full-length cDNA encoding nucleoside diphosphate kinase (NDPK) was cloned us- ing yeast two-hybrid approach.A tobacco NDPK gene was obtained and designated as ***1 is 704.bp in length and en- codes a putative 16.2 kD protein of 14. amino *** analysis showed that NtNDPK1 is highly homologous to other plant NDPK genes and identified as type I (NDPK1).RNA-gel blot analysis showed that there was no significant difference of NtNDPK1 ex- pression in roots,stems,leaves and *** expression of NtNDPK1 was induced by ABA and PEG and repressed by NaCl,but not significantly affected by Paraquat,wounding and low temperature (4.) treatments,indicating that NtNDPK1 may play a certain role in response to abiotic *** vitro phosphorylation assay demonstrated that NtNDPK1 had autophosphoryLation activity.

关键词： abiotic stress autophosphorylation activity NtNDPK1 tobacco yeast two-hybrid

Intrafloral differentiation of stamens in heterantherous flowers

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Journal of Systematics and Evolution 2009年第1期47卷 43-56页

作者： 1,2Zhong-Lai LUO 1,2Lei GU 1Dian-Xiang ZHANG 1(South china Botanical Garden, chinese academy of sciences, Guangzhou 510650, china) 2(graduate university of chinese academy of sciences, Beijing 10004., china) South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China graduate university of chinese academy of {4. Beijing 100049 China

Flowers that have heteromorphic stamens (heterantherous flowers) have intrigued many researchers ever since the phenomenon was discovered in the 19th century. The morphological differentiation in androecia has been suggested as a reflection of "labor division" in pollination in which one type of stamens attracts pollinators and satisfies their demand for pollen as food and the other satisfies the plant’s need for safe gamete dispersal. The extent and patterns of stamen differentiation differ notably among taxa with heterantherous flowers. Seven species with heteromorphic stamens in three genera were sampled from Leguminosae and Melastomataceae, and the morphological difference of androecia, pollen content, pollen histochemistry and viability, pollen micro-morphology, as well as the main pollinators were examined and compared. Pollen number differs significantly between stamen sets of the same flower in most species investigated, and a correlation of pollen number and anther size was substantiated. Higher pollen viabilities were found in the long (pollinating) stamens of Senna alata (L.) Roxb. and S. bicapsularis (L.) Roxb. Dimorphic pollen exine ornamentation is reported here for the first time in Fordiophyton faberi Stapf. The height of stigma and anther tips of the long stamens in natural conditions was proved to be highly correlated, supporting the hypothesis that they contact similar areas of the pollinator’s body.

关键词： buzz pollination heteranthery labor division pollen micro-morphology pollen number pollination stamen differentiation

Anatomy and ontogeny of unisexual flowers in dioecious Woonyoungia septentrionalis (Dandy) Law (Magnoliaceae)

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Journal of Systematics and Evolution 2009年第4期47卷 263-272页

作者： ~(1,2)Lin FU ~1Qing-Wen ZENG ~1Jing-Ping LIAO ~1Feng-Xia XU~* 1(South china Botanical Garden,chinese academy of sciences,Guangzhou 510650,{4.) 2(graduate university of chinese academy of sciences,Beijing 10004.,{4.) (South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (graduate university of chinese academy of {4. Beijing 100049 China)

Woonyoungia septentrionalis(Dandy)Law is a dioecious species with unisexual flowers in Magnoliaceae. The floral morphology and structure of the species are conspicuously different from other species and are important to the study of floral phylogeny in this *** floral anatomy and ontogeny were investigated to evaluate the systematic position of ***,using scanning electron microscopy and light microscopy. All of the floral organs are initiated acropetally and *** carpels are of conduplicated type without the differentiation of stigma and *** degenerated stamens in the female flowers have the same structures as the normal stamens at the earlier developmental stages,but they do not undergo successive development and eventually *** male floral apex was observed to have the remnants of carpels in a few investigated *** the bisexual flower features could be traced both in the male and female flowers in ***,it suggests that the flower sex in Magnoliaceae tends toward *** well as the unisexual flowers,the reduced tepals and carpels and concrescence of carpels conform to the specialized tendency in Magnoliaceae,which confirms the derived position of *** in this *** the initiation pattern of floral parts of *** is very similar to other species in this family,it needs further investigation and especially comparison with species in Kmeria to evaluate the separation of Woonyoungia.

关键词： floral anatomy Magnoliaceae ontogeny Woonyoungia septentrionalis(Dandy)Law.

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan university Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2 , ZHANG Youshui 3 1. Institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 61004., Sichuan, china 2. {4. university of chinese academy of sciences, Beijing 10004., china 3. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduate university of chinese academy of {4. Beijing China Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 259 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4.1. The Faculty of Geography and Resources Science, Sichuan Normal university, Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, chinese academy of {4., Chengdu 61004., Sichuan, china 3. graduate university of the chinese academy of {4., Beijing 10004., china 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 61004., Sichuan, china The Faculty of Geography and Resources Science Sichuan Normal University Chengdu Sichuan China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduate university of the chinese academy of {4. Beijing China Information Center of Land and Resources Department of Sichuan Province Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Functional analysis of schistosomes EF-hand domain-containing tegument proteins

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chinese Science Bulletin 2007年第15期52卷 2100-2107页

作者： YU FuDong1,2,3,KANG Bin1,3,LI YuanYuan3,4.& LI YiXue1,3 1 Bioinformatics Center,Key Laboratory of Systems Biology,Shanghai Institutes for Biological sciences,chinese academy of Sci-ences,Shanghai 200031,china {4.,Shanghai 200031,china 3 Shanghai Center for Bioinformation Technology,Shanghai 200235,china 4.Key Laboratory of Systems Biology,Shanghai Institutes for Biological sciences,chinese academy of sciences,Shanghai 200031,china Bioinformatics Center Key Laboratory of Systems Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate university of chinese academy of {4. Shanghai China Shanghai Center for Bioinformation Technology Shanghai China Key Laboratory of Systems Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

Schistosomes cause schistosomiasis disease which severely threatens human health. Little is known about the functions of EF-hand domain containing schistosomes tegument proteins other than as an-tigens. More possible functions of these tegument proteins were investigated with in silico analyses including protein-protein functional interaction,site-specific variation and glycosylation modification. The analysis results suggested that schistosomes could actively modulate host immune responses for its own favor through functional interactions with host proteins with immunomodulatory function,and passively regulate host immune responses through sequence variation under positive selection and glycosylating the recognition sites of host immune attack. In addition,the analysis of the C-terminal domain of these tegument proteins indicated that they could assist schistosomes in escaping host immune attacks through inhibiting chemotaxis and non-complement fixing antibody (IgG4. responses. In summary,our results suggested that these tegument antigen proteins could assist schistosomes in escaping and modulating host immune responses for self-protection during the process of host-para-site interaction.

关键词：寄生虫血吸虫皮蛋白质健康