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Contribution of Root and Microbial Respiration to Soil CO_2.Efflux and Their Environmental Controls in a Humid Temperate Grassland of Japan

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of Urban and Environmental Sciences Northeast Normal University Changchun 130024 （China） institute of Biological Sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2.efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2.05 to reveal seasonal changes of soil CO2.efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2.efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2.effiux and root mass at different experimental sites. Soil CO2.efflux, ranging from 4.99 to 16.2. μmol CO2.m^-2.s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82.and 1.2. kg m^-2.in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-30 cm depth varied from 8 to 180 g m^-2.month^-1. Microbial and root respiration rates ranged from 1.35 to 5.51 and 2.72.to 12.06μmol CO2.m^-2.s^-1, respectively. The contribution of root respiration to the total soil CO2.efflux averaged 53%, ranging from 33% to 72.. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2.= 0.9400, P = 0.002. n = 6）, and the root respiration rate was linearly related to the root production at 0-30 cm depth （R2.= 0.6561, P = 0.042. n = 6）.

关键词： grasslands microbial respiration root production root respiration

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奥巴马政府教育改革的政策研究与启示

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外国教育研究 2011年第4期38卷 42-47页

作者：孙颖东北师范大学农村教育研究所吉林长春130024

随着《不让一个儿童掉队》(No Child Left Behind)法案在美国遭到的质疑越来越多,奥巴马政府颁布了新的教育改革政策。其中包括加大学前教育投资、提高课程及评价标准、改革教师相关政策、发展特许公立学校以及普及高等教育等措施。与... 详细信息

随着《不让一个儿童掉队》(No Child Left Behind)法案在美国遭到的质疑越来越多,奥巴马政府颁布了新的教育改革政策。其中包括加大学前教育投资、提高课程及评价标准、改革教师相关政策、发展特许公立学校以及普及高等教育等措施。与《不让一个儿童掉队》法案相比,此次改革具有更强的实践指导意义,但同时也遭到了反对派的质疑。新教育改革政策不仅承担着提高教育整体水平的职责,而且还肩负着使全美各领域从金融危机中复苏的政治任务,因此奥巴马教育改革政策在引起社会公众关注的同时,也引发了学术界的深刻反思。

关键词：奥巴马政府教育改革政策

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发展中国家应对技术扩散的劳动力教育政策探析

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外国教育研究 2007年第11期34卷 74-77页

作者：孟宪生唐德先东北师范大学经济与社会发展研究所吉林长春130024 东北师范大学研究生院吉林长春130024

借助国际技术扩散推进国内技术进步,是经济后起国家实现跨越式发展的重要手段。技术效应的扩散程度是以劳动者技术获得能力为前提的,而劳动力教育政策体系又是劳动者技术获得能力的重要影响因素。发展中国家构建以提高技术获得能力为主... 详细信息

借助国际技术扩散推进国内技术进步,是经济后起国家实现跨越式发展的重要手段。技术效应的扩散程度是以劳动者技术获得能力为前提的,而劳动力教育政策体系又是劳动者技术获得能力的重要影响因素。发展中国家构建以提高技术获得能力为主旨的劳动力教育政策体系,既要符合国情要求,又要体现与技术全球化传播及扩散趋势相适应的共性规律。

关键词：发展中国家技术获得能力技术扩散劳动力教育政策

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Transient expression of acidic fibroblast growth factor in pea (Pisum sativum L.) plants

Transient expression of acidic fibroblast growth factor in p...

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第十一届全国植物基因组学大会

作者： Yajun Fan~(1,2.,Wei Li~1,Junjie Wang~1,Jingying Liu~1,Meiying Yang~3,Xiaojuan Zhu~1,Xingzhi Wang~(1 *) 1 institute of genetics and {2.,northeast normal university,changchun 13002.,china 2.Department of Biology,changchun normal university,changchun 130032.china 3 College of life sciences,Jilin Agricultural university,changchun 130118,china

Using Agrobacterium-mediated transient expression system,modified pea early browning virus (PEBV) vectors pCAPE2.GFP and pCAE1 were introduced into pea plants by vacuum infiltration of germinated *** germination the s...

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Use of the modified viral satellite DNA vector to silence mineral nutrition-related genes in plants: silencing of the tomato ferric chelate reductase gene, FRO1, as an example

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Science china(Life Sciences) 2008年第5期51卷 402-409页

作者： HE XiuXia1,2.JIN ChongWei1, LI GuiXin3, YOU GuangYi4, ZHOU XuePing3 & ZHENG ShaoJian4 1 Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education, College of Environmental and Resource Science, Zhejiang university, Hangzhou 31002., china 2.College of Life Science, {2. university of Science and Technology, changchun 13002., china 3 institute of Biotechnology, Zhejiang university, Hangzhou 31002., china 4 State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang university, Hangzhou 310058, china 1. Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education College of Environmental and Resource Science Zhejiang University Hangzhou 310029 China 2. College of Life Science Changchun University of Science and Technology Changchun 130022 China 3. institute of Biotechnology Zhejiang University Hangzhou 310029 China 4. State Key Laboratory of Plant Physiology and Biochemistry College of Life Science Zhejiang University Hangzhou 310058 China

Virus-induced gene silencing (VIGS) is potentially an attractive reverse-genetics tool for studies of plant gene function, but whether it is effective in silencing mineral nutritional-related genes in roots has not been demonstrated. Here we report on an efficient VIGS system that functions in tomato roots using a modified viral satellite DNA (DNAmβ) associated with Tomato yellow leaf curl china virus (TYLCCNV). A cDNA fragment of the ferric chelate reductase gene (FRO1) from tomato was inserted into the DNAmβ vector. Tomato roots agro-inoculated with DNAmβ carrying both a fragment of FRO1 and TYLCCNV used as a helper virus exhibited a significant reduction at the FRO1 mRNA level. As a consequence, ferric chelate reductase activity, as determined by visualization of the pink FeBPDS3 complex was significantly decreased. Our results clearly demonstrated that VIGS system can be employed to investigate gene function associated with plant nutrient uptake in roots.

关键词： virus-induced gene silencing roots ferric chelate reductase

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Cloning of plastid division gene GlFtsZ from Gentiana lutea and its expression during petal development

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Progress in Natural Science:Materials International 2002年第8期 34-39+84页

作者： HE Yikun , ZHU Changfu , WANG Dong, KONG Dongdong and SUN Jingsan(1. institute of Botany, Chinese Academy of Sciences, Beijing 100093, china 2. Department of Biology, Capital {2. university, Beijing 100037, china 3. College of Life Science, northeast normal university, changchun 13002., china) institute of Botany，Chinese Academy of Sciences，Beijing 100093，china Department of Biology，Capital normal university，Beijing 100037，{2. College of Life Science，northeast normal {2.，changchun 13002.，china institute of Botany，Chinese Academy of Sciences，Beijing 100093，china

A full-length cDNA of GlFtsZ was isolated by screening the cDNA library of Gentiana lutea. Analysis of the deduced amino acid sequence encoded by GIFtsZ indicated that GIFtsZ protein possesses the typical conservative motifs existed in all FtsZ proteins. The existence of putative plastid transit peptide in its N-terminus suggested that GIFtsZ might function inside of plastids. With the developmental process of petals of Gentiana lutea, the expression of plastid division gene GIFtsZ declined gradually, whereas the expression of carotenoids biosynthesis gene Zds increased obviously; meanwhile, in contrast to the increment of carotenoids, the content of chlorophyll in petals decreased sharply. The chloroplasts turned into chromoplasts, and the color of petals also turned from green to golden. All of these results suggested that the expression of GIFtsZ is accompanied with the development and differentiation of plastids.

关键词： FtsZ gene plastids chromoplasts Gentiana lutea .

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Mercury pollution in Rana Chensinensis in Weisha River reach, in the upstream region of Songhua River

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Science Bulletin 2005年第19期 48-52页

作者： WANG Ning1, ZHU Yanming2. SHENG Lianxi 1 & MENG Dan1 1. College of Urban and Environmental Sciences of northeast normal university, changchun 13002.,{2. 2. northeast institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, changchun 13002.,{2.

Twice a year continuous samples of Rana Chensinensis and sediments have been collected near gold mine in the upstream region of Songhua River from 2.00 to 2.02. for analyzing the total mercury (THg), methylmercury (MeHg) concentration and correlation in sediments, muscles, livers of the frog. The study indicates that THg and MeHgconcentrations in polluted samples near the gold mine are higher than those in unpolluted ones. THg and MeHg con-centrations are higher in autumn, in female, and in livers than those in spring, in male, in muscles respectively. The order of concentration degree in the frog organizations is as follows: liver>muscle>ovum>Fallopian tube. MeHg is themain form of mercury (Hg) existing in autumn, while inor-ganic Hg is in spring. There is no distinct difference ofCMeHg/CTHg between male and female, livers and muscles. The correlation between MeHg concentrations in the river sedi-ments and in the frog’s livers and muscles are significant, which is related to disorderly discharge of Hg.

关键词： Rana Chensinensis mercury and methylmercury sedi-ment Songhua River

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