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1	Regional Constraints on Leaf Physiognomy and Precipitation Regression Models: A Case Study From China Su, Tao, Spicer, Robert A., Liu, Yu Sheng Christopher, Huang, Yong Jiang, Xing, Yao Wu, Jacques, Frédéric M.B., Chen, Wen Yun, Zhou, Zhe Kun 09 July 2013 (has links) The relationship between leaf physiognomy and precipitation has been explored worldwide in regions under different climate conditions. Unlike the linear relationship established between the percentage of woody dicot species with entire margins and mean annual temperature, precipitation has been reported to correlate to different leaf physiognomic characters depending on the region where the correlation is studied. To investigate if precipitation can be calculated from leaf physiognomic characters on the basis of regional sample sites, data from 50 mesic to humid forests in China were analyzed in this study. With data from Chinese forests, the leaf-area analysis based on linear regression between natural logarithms of leaf size and mean annual precipitation (MAP) shows no significant correlation. Both single and multiple linear regression analyses fail to confirm the correlation between leaf physiognomy and precipitation, which may result from the similarity of modern spatial distribution of temperature and precipitation in China. Our results show that, due to variations in climatic conditions among sampling regions, leaf physiognomic characters that correlate to precipitation are not consistent worldwide, and applications of models without considering regional constraints could mislead our understanding of palaeoclimate. Therefore, when choosing a leaf physiognomic model for palaeoclimate reconstructions, it is important to determine if the leaf physiognomy of the palaeoflora lies within the leaf physiognomic spectrum of the model used. CLAMP leaf size palaeoclimate reconstruction Palaeoflora precipitation
2	Regional Constraints on Leaf Physiognomy and Precipitation Regression Models: A Case Study From China Su, Tao, Spicer, Robert A., Liu, Yu Sheng Christopher, Huang, Yong Jiang, Xing, Yao Wu, Jacques, Frédéric M.B., Chen, Wen Yun, Zhou, Zhe Kun 09 July 2013 (has links) The relationship between leaf physiognomy and precipitation has been explored worldwide in regions under different climate conditions. Unlike the linear relationship established between the percentage of woody dicot species with entire margins and mean annual temperature, precipitation has been reported to correlate to different leaf physiognomic characters depending on the region where the correlation is studied. To investigate if precipitation can be calculated from leaf physiognomic characters on the basis of regional sample sites, data from 50 mesic to humid forests in China were analyzed in this study. With data from Chinese forests, the leaf-area analysis based on linear regression between natural logarithms of leaf size and mean annual precipitation (MAP) shows no significant correlation. Both single and multiple linear regression analyses fail to confirm the correlation between leaf physiognomy and precipitation, which may result from the similarity of modern spatial distribution of temperature and precipitation in China. Our results show that, due to variations in climatic conditions among sampling regions, leaf physiognomic characters that correlate to precipitation are not consistent worldwide, and applications of models without considering regional constraints could mislead our understanding of palaeoclimate. Therefore, when choosing a leaf physiognomic model for palaeoclimate reconstructions, it is important to determine if the leaf physiognomy of the palaeoflora lies within the leaf physiognomic spectrum of the model used. CLAMP leaf size palaeoclimate reconstruction Palaeoflora precipitation
3	Photosynthetic Capacity, Leaf Size and Plant Height in Wheat (Triticum aestivum L.) Bishop, Deborah L. 01 May 1991 (has links) Plant breeders often examine leaf size, plant height and photosynthetic capacity in an effort to increase wheat yield. This study was concerned with the relationship between these parameters in dwarf and semidwarf wheat cultivars (Triticum aestivum L.) with a wide range in flag leaf size. Photosynthetic capacity was measured at anthesis using photosynthesis versus intercellular CO2 response curves to determine maximum photosynthetic rate and ribulose-1,5- bisphosphate carboxylase efficiency. Leaf area, chlorophyll concentration, stomatal density, interveinal distance and dry mass partitioning were also examined. Smaller flag leaves had greater carboxylation efficiency and closer vein spacing. Dwarf wheat had higher chlorophyll concentrations and maximum photosynthetic rates at anthesis than the taller semi-dwarfs. Dwarf cultivars had lower photosynthetic rates before anthesis, suggesting preanthesis feedback inhibition of photosynthesis, possibly due to a smaller sink capacity of its stem. photosynthetic capacity leaf size plant height wheat Plant Sciences
4	Aboveground and belowground response of European beech to drought: field studies and experiments / Ober- und unterirdische Reaktion der Rotbuche auf Trockenheit: Freilandstudien and Experimente Meier, Ina Christin 03 May 2007 (has links) No description available. 580 Pflanzen (Botanik) WNA 250 WNO 000 Mathematics and Natural Science Altbäume Blattgröße Blattstreckung Bodenfeuchte common garden-Experiment δ<sup>13</sup>C-Gehalt Fagus sylvatica Feinwurzelbiomasse Feinwurzellebensdauer Feinwurzelproduktion genetische Variabilität LAI Minirhizotrone Niederschlagsgradient Optimalitätstheorie phänotypische Plastizität Rotbuche Trockenheit Wurzellabor Wurzelmorphologie adult trees common garden experiment δ<sup>13</sup>C-signature Fagus sylvatica fine root biomass fine root longevity fine root production fine root turnover genetic variability LAI leaf expansion leaf size mini-rhizotrons optimal partitioning theory phenotypic plasticity precipitation gradient rhizolab root morphology soil moisture 42.91

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