Du Ning, Fan Jintu, Chen Shuo, Liu Yang
Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
J Theor Biol. 2008 Jul 21;253(2):393-400. doi: 10.1016/j.jtbi.2008.03.016. Epub 2008 Mar 19.
Although recent investigations [Ryan, M.G., Yoder, B.J., 1997. Hydraulic limits to tree height and tree growth. Bioscience 47, 235-242; Koch, G.W., Sillett, S.C.,Jennings, G.M.,Davis, S.D., 2004. The limits to tree height. Nature 428, 851-854; Niklas, K.J., Spatz, H., 2004. Growth and hydraulic (not mechanical) constraints govern the scaling of tree height and mass. Proc. Natl Acad. Sci. 101, 15661-15663; Ryan, M.G., Phillips, N., Bond, B.J., 2006. Hydraulic limitation hypothesis revisited. Plant Cell Environ. 29, 367-381; Niklas, K.J., 2007. Maximum plant height and the biophysical factors that limit it. Tree Physiol. 27, 433-440; Burgess, S.S.O., Dawson, T.E., 2007. Predicting the limits to tree height using statistical regressions of leaf traits. New Phytol. 174, 626-636] suggested that the hydraulic limitation hypothesis (HLH) is the most plausible theory to explain the biophysical limits to maximum tree height and the decline in tree growth rate with age, the analysis is largely qualitative or based on statistical regression. Here we present an integrated biophysical model based on the principle that trees develop physiological compensations (e.g. the declined leaf water potential and the tapering of conduits with heights [West, G.B., Brown, J.H., Enquist, B.J., 1999. A general model for the structure and allometry of plant vascular systems. Nature 400, 664-667]) to resist the increasing water stress with height, the classical HLH and the biochemical limitations on photosynthesis [von Caemmerer, S., 2000. Biochemical Models of Leaf Photosynthesis. CSIRO Publishing, Australia]. The model has been applied to the tallest trees in the world (viz. Coast redwood (Sequoia sempervirens)). Xylem water potential, leaf carbon isotope composition, leaf mass to area ratio at different heights derived from the model show good agreements with the experimental measurements of Koch et al. [2004. The limits to tree height. Nature 428, 851-854]. The model also well explains the universal trend of declining growth rate with age.
尽管最近的研究[瑞安，M.G.，约德，B.J.，1997年。树木高度和树木生长的水力限制。《生物科学》47，235 - 242；科赫，G.W.，西利特，S.C.，詹宁斯，G.M.，戴维斯，S.D.，2004年。树木高度的限制。《自然》428，851 - 854；尼克拉斯，K.J.，施帕茨，H.，2004年。生长和水力（而非机械）限制控制着树木高度和质量的缩放比例。《美国国家科学院院刊》101，15661 - 15663；瑞安，M.G.，菲利普斯，N.，邦德，B.J.，2006年。重新审视水力限制假说。《植物细胞环境》29，367 - 381；尼克拉斯，K.J.，2007年。植物最大高度及其限制的生物物理因素。《树木生理学》27，433 - 440；伯吉斯，S.S.O.，道森，T.E.，2007年。利用叶性状的统计回归预测树木高度的限制。《新植物学家》174，626 - 636]表明，水力限制假说（HLH）是解释树木最大高度的生物物理限制以及树木生长速率随年龄下降的最合理理论，但分析大多是定性的或基于统计回归。在此，我们提出一个综合生物物理模型，其基于树木发展生理补偿机制（例如叶水势下降以及导管随高度变细[韦斯特，G.B.，布朗，J.H.，恩奎斯特，B.J.，1999年。植物维管系统结构和异速生长的通用模型。《自然》400，664 - 667]）以抵抗随高度增加的水分胁迫这一原理，结合经典的HLH以及光合作用的生化限制[冯·卡默勒，S.，2000年。叶片光合作用的生化模型。澳大利亚CSIRO出版社]。该模型已应用于世界上最高的树木（即海岸红杉（红杉））。模型得出的不同高度处的木质部水势、叶碳同位素组成、叶质量面积比与科赫等人[2004年。树木高度的限制。《自然》428，851 - 854]的实验测量结果显示出良好的一致性。该模型还很好地解释了生长速率随年龄下降的普遍趋势。
Zotero 插件