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Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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Science china Earth Sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth environment, Chinese Academy of Sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of Sciences, Beijing 100049, china 3 college of Resources and environmental Science, Nanjing agricultural university, Nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate university of the Chinese Academy of Sciences Beijing China college of Resources and environmental Science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

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The Recognition of Glycolate Oxidase Apoprotein with Flavin Analogs in Higher Plants

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 290-296页

作者： Wei-Jun WANG*, Jing-Quan HUANG, Chong YANG, Jiu-Jiu HUANG, and Ming-Qi LI college of Life Science, South china agricultural university, Guangzhou 510642, china college of Life Science South China Agricultural UniversityGuangzhou 510642 China

The dependence of glycolate oxidase apoprotein (apoGO) activity on flavin analogs was surveyed in 9 higher plants from 7 families. Activities of all apoGOs depended not only on flavin mono- nucleotide (FMN) but also on flavin adenine dinucleotide (FAD), but not on riboflavin. The kinetic analysis showed that FMN was the optimum cofactor for apoGO from leaves of Brassica campestris. In plant kingdom, FMN, FAD and riboflavin are three flavin analogs with very similar structure, and they could coexist and be inter-converted from each other, so the question is how the apoprotein of glycolate oxidase (GO) recognized these flavin analogs. No inhibition effect of riboflavin on the activity of apoGO with FMN or FAD was found and no obvious quenching of riboflavin or apoGO protein fluorescence was detected with the addition of apoGO or riboflavin, respectively. These results indicated that riboflavin did not bind to apoGO tightly like FMN and FAD. Inorganic phosphate (Pi) did inhibit the activity of GO, and kinetic analysis revealed that this inhibition was caused by the competitive binding to apoGO between Pi and FMN. This competitive binding was further confirmed by the inhibition of Pi to the quenching of FMN and apoGO protein fluorescence with apoGO and FMN, respectively. It was suggested that the 5’-phosphate group of FMN or FAD may play a key role in the recognition and binding of riboflavin analog cofactors with apoGO.

关键词： glycolate oxidase in higher plant flavin analogs 5’-phosphate moiety recognition

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Chemical and Biological Evaluation of Maturity of Pig Manure Compost at Different C/N Ratios

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Pedosphere 2001年第3期11卷 243-250页

作者： HUANG GUOFENG WU QITANG LI FANGBAI and J. W. C. WONG college of Natural Resources and environment, South china agricultural university, Guangzhou 510642 (china) Department of Biology, Hong Kong Baptist university, Hong Kong (china) 华南农业大学广东 510642 香港浸会大学香港

Aerobic static pile composting (mechanical turning every 3 days) of pig manure was prepared at & m3 windrow heaps. Sawdust was used as the bulking agent to provide additional carbon and to increase the porosity of the substrate. Two treatments at initial C/N ratios of 30 and 15, respectively, were designed in the study. Dissolved organic carbon (DOC), soluble NH+4-N, C/N ratios in solid and aqueous phases, E4/E6 ratios, and seed germination index (GI) were determined to evaluate the maturity of the co-composts. Seed germination index, a biological parameter, was suggested as one of the most reliable maturity indicators for organic compost. The results showed that the treatment at the initial C/N ratio of 30 reached maturity after 49 days of composting; however, the treatment at the initial C/N ratio of 15 should require composting time of longer than 63 days to obtain maturation. Chemical multi-indicator evaluation was necessary, and the GI measurement was the recommended approach for maturity evaluation in the study.

关键词： C/N ratio composting maturity pig manure

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Binding and Transformation of Extracellular DNA in Soil

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Pedosphere 2005年第1期15卷 16-23页

作者： CAIPeng HUANGQiao-Yun ZHANGXue-Wen CHENHao StateKeyLaboratoryofagriculturalMicrobiology CollegeofResourcesandEnvironmentHuazhongAgricultureUniversityWuhan430070China StateKeyLaboratoryofagriculturalMicrobiology CollegeofResourcesandEnvironmentHuazhongAgricultureUniversityWuhan430070China／／CollegeofScienceHuazhongAgricultureUniversityWuhan430070China collegeofScience HuazhongAgricultureUniversityWuhan430070China

DNA is the genetic material of various organisms. Extracellular DNA adsorbed or bound on surface-active particles in soils has been shown to persist for long periods against nucleases degradation and still retain the ability to transform competent cells. This paper reviews some recent advances on the binding and transformation of extracellular DNA in soils, which is fundamental to understanding the nature of the soil, regulating biodiversity, and assessing the risk of releasing genetically engineered microo…

关键词： adsorption binding extracellular DNA soil transformation

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On Form Invariance,Lie Symmetry and Three Kinds of Conserved Quantities of Generalized Lagrange's Equations

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Communications in Theoretical Physics 2007年第7期48卷 37-42页

作者： ZHAO Shu-Hong LIANG Li-Fuoi School of Civil Engineering,Harbin Engineering university,Harbin 150001,china2 Engineering college,Northeast agricultural university,Harbin 150030,china School of Civil Engineering Harbin Engineering University Harbin 150001 China Engineering college Northeast Agricultural University Harbin 150030 China

In this paper,the form invariance and the Lie symmetry of Lagrange's equations for nonconservativesystem in generalized classical mechanics under the infinitesimal transformations of group are studied,and the Noether'sconserved quantity,the new form conserved quantity,and the Hojman's conserved quantity of system are derived ***,an example is given to illustrate the application of the result.

关键词： form invariance Lie symmetry conserved quantity generalized classical mechanics Lagrange’s equation

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Effects of chronic exposure to nonylphenol on locomotor activity and social behavior in zebrafish(Danio rerio)

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Journal of environmental Sciences 2010年第9期22卷 1435-1440页

作者： Jigang Xia,Cuijuan Niu ,Xuejiao Pei Ministry of Education Key Laboratory of Biodiversity Science and ecological Engineering,college of Life Sciences,Beijing Normal university,100875 Beijing,china. Ministry of Education Key Laboratory of Biodiversity Science and ecological Engineering College of Life Sciences Beijing Normal University 100875 Beijing China

Nonylphenol （NP）, a xenoestrogen ubiquitously found in aquatic ecosystems, is of high environmental concern. The present work assessed the effects of exposure to NP on locomotor activity and social behavior in male and female zebrafish （Danio rerio）, to evaluate the possible hazard of NP to fish behavior and to pursue a potential biomarker of NP contamination. Fish were randomly divided into six groups. Five groups were receiving 0.1, 1, 10, 50 and 100 μg/L nominal concentrations of NP for 60 days, respectively. A sixth control group was given the same treatment as the other five groups, but no NP. Locomotor activity, aggressive behavior, group preference and leaving shoal were examined. NP exposure showed marked influence on locomotor activity of the male zebrafish, whereas that of the female was not significantly affected by NP. Aggressive behavior and group preference were significantly affected by NP exposure in both male and female groups. Locomotor activity and aggressive behavior of the male and group preference of both male and female zebrafish were clearly inhibited at 100 μg/L NP. No significant alteration in leaving shoal was observed under NP exposure. The results suggested that changes in locomotor activity and aggressive behavior of the male and group preference of both male and female may be used as an ecologically relevant integrative biomarker of NP contamination.

关键词： chronic toxicity nonylphenol biomarker zebrafish

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Research on the method for retrieving soil moisture using thermal inertia model

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Science china Earth Sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2 1. Information college, South china agricultural university, Guangzhou 510642, china 2. Graduate university of Chinese Academy of Sciences, Beijing 100049, china Information college South China Agricultural University Guangzhou China Graduate university of Chinese Academy of Sciences Beijing China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west inner mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

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Effects of Fe and Mn in Paddy Soils Derived from Different Parent Materials on Methane Production and Emission

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Pedosphere 2003年第4期13卷 337-344页

作者： LIU Ke-Xing, LIAO Zong-Wen, WANG Sheng-Chun and YOU Zhi-Lincollege of Natural Resources and environment, South china agricultural university, Guangzhou 510642 college of Natural Resources and environment South China AyricuUural University Guangzhou 510642

Three types of paddy soils, derived from granite, Quaternary red clay andbasalt, respectively, were selected to study the effects of Fe and Mn in paddy soils on methaneproduction and emission through pot and incubation experiments. The results indicated that thedifference of Fe and Mn in paddy soils was one of the important factors causing obvious differencesin methane emission from different soil types. Soil Fe and Mn affecting methane emission from thepaddy soils was likely through affectingsoil Eh and forming Fe and Mn plagues on rice *** rates and valences of added Fe and Mn significantly affected methane production from paddysoils. Therefore, this study enhanced understanding of processes controlling methane emission frompaddy soils and may help to improve modeling and estimating regional and global methane emissionfrom paddy soils.

关键词： Fe methane emission methane production Mn paddy soil

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Effect of Perched Water Tables on Aluminosilicate Stability and Soil Genesis

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Pedosphere 2000年第3期10卷 247-256页

作者： ZHANG MIN , GONG ZITONG and A. D. KARATHANASIS college of Resources and environment, Shandong agricultural university, Tai’an 271018 (china) Institute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (china) college of Agriculture, U 山东农业大学山东泰安 271018 中科院南京土壤所江苏南京 210008 university of Kentucky 美国 Lexington KY40546-00

The mineral stability and solute activities of soil solution extracted from selected horizons of seven studied pedons of Alfisols in Kentucky, USA, and the relationship between distribution of iron-manganese concretions and the restrictive layers were investigated. The results showed that the genesis and development of these soils and mineral weathering trends were strongly influenced by the depth of bedrock and the presence of perched water tables at lithic (limestone) interfaces due to the dissolution and buffering effect of limestone bedrock. The extractable Mg/Ca ratio as depth function and soil depth above bedrock could be used as indices of weathering and degree of soil development. Maximum iron-manganese concretion accumulation was found to occur in the horizon overlying clay horizon (>40% clay) with a sharp increase in clay content (>10%), which suggested that zones of Fe-Mn concretion accumulation in soils of the inner Bluegrass Region appeared to be a sensitive genetic indicator of argillic horizons with restrictive permeability.

关键词： iron-manganese concretion perched water table soil environment soil genesD

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GLOBALIZATION AND RESPONSE OF LARGE STATED-OWNED ENTERPRISES IN agricultural RELATED INDUS-TRIES: COMPANY CASE STUDIES FROM CENTRAL china

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Chinese Geographical Science 2001年第2期11卷 120-128页

作者： LI Xiao-jian (college of environment and Planning, Henan university, Kaifeng 475001, P.R.china) college of environment and Planning Henan University Kaifeng P. R. China

By using interview data from three large state-owned enterprises (SOEs) in agriculture related industries, this paper reveals that SOEs in inland area are much slow in response to globalization. Although they pursued some strategies to adjust themselves, they are far behind the position to utilize the opportunities generated by economic globalization. Most of them are still out of the networks of transnational corporations. The strategies they adopted are quite different from SOEs in the coastal area. They overlook the importance of information infrastructure, well-educated personnel, and collaboration with the competitive leaders in their industries. The lagging situation is related to isolated location, traditional culture, and slow progress in enterprise reform. International comparison shows that the case companies did follow the general patterns that globalization promotes extension of company′s networks of linkages but in a rather slow phase. The decision makers should encourage intra-regional linkages between SOEs, between SOEs and private, foreign owned companies, as well as inter-regional linkages among them. The latter appears particularly important given the enlarging gaps between coastal and inland areas.

关键词： state-owned enterprise enterprise reform regional development globalization

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