5 research outputs found

    Phytoplankton biomarkers in surface seawater from the northern South China Sea in summer 2009 and their potential as indicators of biomass/community structure

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    生物标志物已被广泛应用于重建浮游植物生产力和群落结构变化。该方法假设之一是生标的含量可以反映表层海水的浮游植物生物量,但这个假设还缺乏现场观测的充分验证。对2009年冬季南海北部表层海水颗粒物中主要生标做了分析,利用其含量及比值研究浮游植物的生物量及群落结构的分布。生标含量表明硅藻、甲藻、颗石藻的高值区位于珠江口南部及广东沿岸,在陆坡区也有高值。生标比值显示硅藻在3个类群中的相对比例最高。其中,甲藻/硅藻比值高值区位于陆坡区,这与大洋水(黑潮)的入侵,带来大量暖水性甲藻有很大关系;颗石藻/硅藻比值总体趋势与生物量的分布相反,在近岸少数站位有高值,向外海逐渐增加,主要是因为颗石藻更适于寡营养盐的环境。生标结果所指示的生物量及群落结构的空间分布与前人的调查结果类似,为利用生标重建此区域的浮游植物生产力和群落结构变化提供了依据。Biomarkers have been widely used to reconstruct phytoplankton productivity based on the assumption that biomarker contents could reflect phytoplankton productivity in the surface seawater.However,this hypothesis has not been validated with modern survey.In this study,the contents and ratios of three phytoplankton biomarkers in the surface seawater of the northern South China Sea in winter 2009 were analyzed,to indicate spatial distributions of phytoplankton biomass and community structure.The results show high values for diatoms,dinoflagellates and coccolithophorids near the Pearl River Estuary and Guangdong coastal areas.The community structure indicates diatoms are the dominant phytoplankton species in winter.High values of dinoflagellate/diatom ratio occur near the slope area owing to intrusion of the Kuroshio,which favors the growth of dinoflagellates.The coccolithophorid/diatom ratio displays an increasing trend from the Pearl River Estuary to offshore region due to the advantage of coccolithophorids in oligotrophic environment,which is opposite to the productivity pattern of all biomarkers.These results are consistent with previous studies using phytoplankton cell and pigments,which provides support for the use of biomarker to reconstruct phytoplankton productivity and community structure in the SCS.国家重点基础研究发展计划项目(2007CB815934、2009CB421201);国家自然科学基金项目(40776029

    基于笔输入的三维造型系统的体系结构

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    分析了在产品概念设计阶段WIMP交互方式的诸多不足,论述了手势交互的优越性,给出了基于笔输入建立三维造型系统的体系结构,讨论了其中的关键技术问题,如手势设计、手势识别以及基于ACIS几何造型器的造型实现等

    the state-of-the-art of research on constructing 3d conceptual models based on gesture

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    综述了国内外基于手势输入构造三维概念模型的最新研究进展,讨论分析了手势交互过程及其关键技术:手势设计、手势识别、手势交互的层次结构以及手势交互的三维实现·最后对今后的发展方向进行了展望

    Quantum Chemical Study of Chemisorption States For Oxygen on Alkali Metal Oxides and SulFides

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    碱金属氧化物和硫化物晶面上氧吸附态的量子化学研究@戴玉梅@林银钟@陈鸿博@洪琦@易军@陈守正@廖代伟¥福建师范大学化学系¥厦门大学物理化学研究所¥厦门大学化学系¥固体表面物理化学国家重点实验室碱金属氧化物和硫化物晶面上氧吸附态的量子化学研究戴玉梅1林银钟2...The Chemisorption States For O_2 on (100), (110) and (111) surFaces of Li_2O, Li_2S, Na_2O and Na_2S with the Flat-lying model, inclined model and vertical model are studied by CNDO/2LMO.The calculations indicated that, in energy, the (100) surFace and Flatlying model are the most Favorable while the chemisorbed O_2 is excitation state.The results also showed that the decrease in cation radius is in Favor of both chemisorption and activation of oxygen.国家自然科学基金;福建炼油厂资

    2005~2014年CERN野外台站气象观测场土壤含水量数据集

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    土壤水分是影响陆地–大气边界层能量和物质传输的重要因子。土壤水分含量是中国生态系统研究网络(CERN)陆地生态系统水环境长期定位观测的重要指标。截至2014年,CERN全国范围内包括农田、森林、草地、荒漠与湿地等生态类型的34个陆地生态系统台站,依据陆地水环境观测规范、质量保证与质量控制规范,设立观测样地,并开展土壤含水量的长期定位观测与数据汇交及质控工作。CERN水分分中心选取了这34个台站2005~2014年气象观测场的土壤含水量长期监测数据,通过进一步统一规范数据格式,形成了全国范围内较长时间序列的公开共享数据集,为土壤含水量时空动态的遥感反演、模型估算验证提供地面实测数据支撑
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