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植物叶片的形态性状能够有效地反映生存环境的变化,并且影响植物的基本行为和功能。该研究通过获取植物标本提供的叶片形态信息,结合相关分析和标准化主轴分析,探讨了南北样带暖温带区栎属(Quercus)树种叶片形态性状对气候条件的响应及适应策略。结果表明:在南北样带暖温带区,随着气候条件的变化,栎属树种的叶片形态性状发生显著的变化。随着年平均气温的降低和年日照时数的增加,栎属树种叶面积增加,以利于吸收更多的光照辐射,并增加叶片的边界层阻力,减少叶片热量的散失;而叶片分裂程度的增加不仅可以降低热量的散失,也可以提高叶片液流的波动以增强叶片的生理活动;叶脉密度随温度的升高、光照强度和降水量的增加而增加,以响应叶片蒸腾作用的增强,提高水分的运输能力和叶片的支撑能力。此外,为适应南北样带暖温带区气候条件的变化,栎属树种的叶片形成了一系列的形态性状组合,随着叶面积的增加,叶柄长度和叶片分裂程度逐渐增加,而叶脉密度降低;随着叶片倾向于向长条状发展,叶柄长度和叶脉密度也随之增加。
Morphological traits of plant leaves can effectively reflect the changes of living environment and affect the basic behavior and function of plants. In this study, leaf morphological information from plant specimens was obtained. Correlation analysis and standardization of major axis analysis were conducted to investigate the response of leaf morphological characteristics of Quercus species in the warm temperate zone of north and south transects to climatic conditions and adaptation strategies. The results showed that morphological traits of Quercus species changed significantly with the change of climatic conditions in the warm temperate zone of the north and south transects. With the decrease of annual mean temperature and annual sunshine hours, the leaf area of Quercus species increased to absorb more light radiation and increase the resistance of leaf boundary layer and reduce the loss of leaf heat. The degree of leaf fragmentation Increasing can not only reduce the loss of heat, but also increase the fluctuation of leaf flow to enhance the physiological activities of leaves. The leaf density increases with the increase of temperature, light intensity and precipitation, in response to the increase of leaf transpiration, Moisture transport capacity and blade support. In addition, in order to adapt to the change of climatic conditions in the warm temperate zone of the north and south transects, the leaves of the Quercus species formed a series of morphological traits. With the increase of the leaf area, the petiole length and the degree of leaf division gradually increased while the leaf vein density decreased. Petiole length and leaf vein density also increased as leaves tended to elongate.